CDC HAN Advisory & MMWR: HIV & HCV Among Injectable Drug Users

 

# 9974

 

Over the past month we’ve been following the HIV and HCV outbreak in Southeastern Indiana (see Indiana Gov To Declare HIV Health Emergency In Scott County & Scott County HIV Epidemic Reaches 130 Cases) which has now grown to 142 cases. 

 

Reportedly, at least 80% of these cases are injectable drug users, and this practice appears to be driving this epidemic.

 

Today the CDC, along with officials from the State of Indiana, held a 50-minute-long press conference in advance of the release of a CDC HAN  message, and an early release MMWR called  Community Outbreak of HIV Infection Linked to Injection Drug Use of Oxymorphone — Indiana, 2015.

The MMWR describes socio-economic situation in Scott County as:

Injection drug use in this community is a multi-generational activity, with as many as three generations of a family and multiple community members injecting together. IDU practices include crushing and cooking extended-release oxymorphone, most frequently 40 mg tablets not designed to resist crushing or dissolving. Syringes and drug preparation equipment are frequently shared (e.g., the drug is dissolved in nonsterile water and drawn up into an insulin syringe that is usually shared with others). The reported daily numbers of injections ranged from four to 15, with the reported number of injection partners ranging from one to six per injection event.

Like many other rural counties in the United States, the county has substantial unemployment (8.9%), a high proportion of adults who have not completed high school (21.3%), a substantial proportion of the population living in poverty (19%), and limited access to health care (1). This county consistently ranks among the lowest in the state for health indicators and life expectancy (2).

 

And the demographics of the outbreak:

 

The age range of the 135 patients is 18–57 years (mean = 35 years; median = 32 years); 74 (54.8%) are  male. A small number of pregnant women were diagnosed with HIV infection and started on antiretroviral  therapy during pregnancy. As of April 21, no infants had tested positive for HIV. Of the 135 persons with diagnosed HIV infection, 108 (80.0%) have reported injection drug use (IDU), four (3.0%) have reported no IDU, and 23 (17.0%) have not been interviewed to determine IDU status. Among the 108 who have reported IDU, all reported dissolving and injecting tablets of oxymorphone as their drug of choice. Some reported injecting other drugs, including methamphetamine and heroin. Ten (7.4%) female patients have been identified as commercial sex workers. Coinfection with hepatitis C virus has been diagnosed in 114 (84.4%) patients

 

Because the conditions described in Scott county are not necessarily unique to that part of the country, the CDC has issued a HAN Advisory to alert clinicians to be alert to signs of similar outbreaks in their communities, so that public health interventions can come sooner rather than later.

 

Some excerpts from a much longer HAN Advisory follow: 

 

Outbreak of Recent HIV and HCV Infections among Persons Who Inject Drugs

 This is an official CDC HEALTH ADVISORY

Distributed via the CDC Health Alert Network
April 24, 2015, 11:00 ET (11:00 AM ET)
CDCHAN-00377

Summary

The Indiana State Department of Health (ISDH) and the Centers for Disease Control and Prevention (CDC) are investigating a large outbreak of recent human immunodeficiency virus (HIV) infections among persons who inject drugs (PWID). Many of the HIV-infected individuals in this outbreak are co-infected with hepatitis C virus (HCV). The purpose of this HAN Advisory is to alert public health departments and healthcare providers of the possibility of HIV outbreaks among PWID and to provide guidance to assist in the identification and prevention of such outbreaks.

<SNIP>

Recommendations for Health Departments

• Review the most recent sources of data on HIV diagnoses, HCV diagnoses (acute as well as past or present), overdose deaths, admissions for drug treatment, and drug arrests. Attributes of communities at risk for unrecognized clusters of HIV and HCV infection include the following:
  • Recent increases in the:
    • Number of HIV infections attributed to injection drug use,
    • Number of HCV infections, particularly among persons aged < 35 years;
  • High rates of injection drug use and especially prescription-type opioid abuse, drug-related overdose, drug treatment admission, or drug arrests.
• Ensure complete contact tracing for all new HIV diagnoses and testing of all contacts for HIV and HCV infection.
• Ensure persons actively injecting drugs or at high-risk of drug injection (e.g., participating in drug substitution programs, receiving substance abuse counseling or treatment, recently or currently incarcerated) have access to integrated prevention services,⁹ and specifically:
  • Are tested regularly for HIV and HCV infection (consider more frequent testing based on frequency of injection drug usage or sharing of injection equipment);
  • If diagnosed with HIV or HCV infection:
  • Are rapidly linked to care and treatment services;
  • If actively injecting drugs:
    • Have access to medication-assisted therapy (e.g., opioid substitution therapy) as well as other substance abuse services, if not already engaged,
    • Are counseled not to share needles and syringes or drug preparation equipment (e.g., cookers, water, filters),
    • Have access to sterile injection equipment from a reliable source.
  • If not HIV infected but actively injecting drugs:
    • Are referred for consideration of HIV pre-exposure prophylaxis¹⁰ and if potentially exposed within the past 72 hours (e.g., shared drug preparation or injection equipment with a known or potentially HIV-infected person) HIV post-exposure prophylaxis^11,12
• Remind venues that may encounter unrecognized infections, such as emergency departments and community-based clinical practices (e.g., family medicine, general medicine, prenatal care) of the importance of routine opt-out HIV testing as well as HCV testing per current recommendations^13-15
• Local health departments should notify their state health department and CDC of any suspected clusters of recent HIV or HCV infection.

Recommendations for Healthcare Providers

• Ensure all persons diagnosed with HCV infection are tested for HIV infection,¹⁶ and that all persons diagnosed with HIV infection are tested for HCV infection.¹⁷
• Ensure persons receiving treatment for HIV and/or HCV infection adhere to prescribed therapy and are engaged in ongoing care.
• Encourage HIV and HCV testing of syringe-sharing and sexual partners of persons diagnosed with either infection.
• Report all newly diagnosed HIV and HCV infections to the health department.
• For all persons with substance abuse problems:
  • Refer them for medication-assisted treatment (e.g., opioid substitution therapy) and counseling services,
  • Use effective treatments (e.g., methadone, buprenorphine), as appropriately indicated.
• For any persons for whom opioids are under consideration for pain management:
  • Discuss the risks and benefits of all pain treatment options, including ones that do not involve prescription analgesics.
  • Note that long-term opioid therapy is not associated with reduced chronic pain.¹⁸
• Contact the state or local health department to report suspected clusters of recent HIV or HCV infection.

(Continue . . .)

MMWR: Outbreaks Of HPAI H5N2, H5N8 & H5N1 Among Birds – United States

# 9668

 

Over the weekend, in  CDC Interim Guidance On Antiviral Chemoprophylaxis For Persons With Exposure To Avian Flu  and CDC Interim Guidance For Testing For Novel Flu, we looked at new guidance released by the CDC on Friday night in light of recent detections of HPAI H5 viruses in wild birds and poultry in the United States.

 

While human infection with these specific H5 viruses have not been reported, they are related to H5 subtypes that have caused severe (even fatal) infections before.  Therefore, the CDC is taking a cautious approach.

Today in an Early Release from the MMWR, we get an overview of the recent incursion of Highly Pathogenic H5 avian flu into North America, along with links to the new guidance documents, and some rationale behind the CDC’s cautious stance.

 

 

Outbreaks of Avian Influenza A (H5N2), (H5N8), and (H5N1) Among Birds — United States, December 2014–January 2015

Early Release

February 3, 2015 / 64(Early Release);1-1

Michael A. Jhung, MD1, Deborah I. Nelson, PhD2 (Author affiliations at end of text)

During December 15, 2014–January 16, 2015, the U.S. Department of Agriculture received 14 reports of birds infected with Asian-origin, highly pathogenic* avian influenza A (HPAI) (H5N2), (H5N8), and (H5N1)† viruses. These reports§ represent the first reported infections with these viruses in U.S. wild or domestic birds. Although these viruses are not known to have caused disease in humans, their appearance in North America might increase the likelihood of human infection in the United States. Human infection with other avian influenza viruses, such as HPAI (H5N1) and (H5N6) viruses and (H7N9) virus, has been associated with severe, sometimes fatal, disease (1–3), usually following contact with poultry.

The 14 HPAI H5 detections, seven (H5N2), six (H5N8), and one (H5N1), occurred in five northwestern states (California, Idaho, Oregon, Utah, and Washington). Outbreaks occurred in five domestic, backyard flocks, two captive wild birds, and seven wild aquatic birds. All backyard flocks were destroyed after identification of HPAI H5 virus. Of 24 persons reporting exposure to infected birds, one person developed influenza-like illness (ILI) after exposure but subsequently tested negative for influenza.

CDC has developed testing (http://www.cdc.gov/flu/avianflu/severe-potential.htm) and influenza antiviral prophylaxis (http://www.cdc.gov/flu/avianflu/guidance-exposed-persons.htm) guidance for persons exposed to birds possibly infected with HPAI H5 viruses. Until more is known about these viruses, CDC is taking a cautious approach, and recommendations are largely consistent with guidance for influenza viruses associated with severe disease in humans. Clinicians and public health workers should consider the possibility of infection with HPAI H5 viruses in patients with ILI who have had recent contact with sick or dead birds, especially in areas where these viruses have been identified. Persons exposed to birds infected with HPAI H5 should be monitored for ILI for 10 days after their last exposure, and influenza antiviral prophylaxis may be considered to prevent infection. Persons who develop ILI after exposure to HPAI H5-infected birds should be tested immediately for influenza by the state health department. State health departments are encouraged to investigate all possible human infections with HPAI H5 virus and should notify CDC promptly when testing for influenza in persons with ILI who have been exposed to birds possibly infected with these viruses.

1Influenza Division, National Center for Immunization and Respiratory Disease, CDC. 2Animal and Plant Health Inspection Service, U.S. Department of Agriculture, Fort Collins, Colorado (Corresponding author: Michael A. Jhung, mjhung@cdc.gov, 404-639-3747)

References

1. Uyeki TM. Human infection with highly pathogenic avian influenza A (H5N1) virus: review of clinical issues. Clin Infect Dis 2009;49:279–90.
2. Gao HN, Lu HZ, Cao B, et al. Clinical findings in 111 cases of influenza A (H7N9) virus infection. N Engl J Med 2013;368:2277–85.
3. Bi Y, Mei K, Shi W, et al. Two novel reassortants of avian influenza A (H5N6) virus in China. J Gen Virol 2015. Epub ahead of print.

* Highly pathogenic refers to the spectrum of illness seen in birds.

† The H5N1 virus isolated from a U.S. wild bird is a new mixed-origin virus (a reassortant) that is genetically different from the avian H5N1 viruses that have caused human infections with high mortality in several other countries (notably in Asia and Africa). No human infections with this new reassortant H5N1 virus have been reported.

MMWR: MERS Epidemiological Update & Guidance

Coronavirus – Credit CDC PHIL

 

# 9645

 

While all eyes right now are on our current flu season, and the merry band of novel flu viruses harassing people and poultry operations on four continents (Africa, Asia, Europe, North America) - if last year is any indication - in a few months the MERS coronavirus will be making headlines as well.

 

As the chart below from today’s MMWR illustrates, MERS seems to blossom in the spring, although exactly why is still up for grabs.  The most popular theory involves the winter calving of camels. Young camel are the most susceptible to the virus, and are believed a likely conduit to pass it on to humans.

FIGURE. Number of cases of Middle East respiratory syndrome coronavirus infection reported by the World Health Organization,* by month of illness onset — worldwide, 2012–2015

 

As both a `head’s up’ and an overview, today the MMWR has published a brief epidemiological review of the MERS coronavirus.

Update on the Epidemiology of Middle East Respiratory Syndrome Coronavirus (MERS-CoV) Infection, and Guidance for the Public, Clinicians, and Public Health Authorities — January 2015

Weekly

January 30, 2015 / 64(03);61-62

Brian Rha, MD1, Jessica Rudd, MPH1, Daniel Feikin, MD1, John Watson, MD1, Aaron T. Curns, MPH1, David L. Swerdlow, MD2, Mark A. Pallansch, PhD1, Susan I. Gerber, MD1 (Author affiliations at end of text)

CDC continues to work with the World Health Organization (WHO) and other partners to closely monitor Middle East respiratory syndrome coronavirus (MERS-CoV) infections globally and to better understand the risks to public health. The purpose of this report is to provide a brief update on MERS-CoV epidemiology and to notify health care providers, public health officials, and others to maintain awareness of the need to consider MERS-CoV infection in persons who have recently traveled from countries in or near the Arabian Peninsula.*

MERS-CoV was first identified and reported to WHO in September 2012 (1). As of January 23, 2015, WHO has confirmed 956 laboratory-confirmed† cases of MERS-CoV infection, which include at least 351 deaths. All reported cases have been directly or indirectly linked through travel or residence to nine countries: Saudi Arabia, the United Arab Emirates, Qatar, Jordan, Oman, Kuwait, Yemen, Lebanon, and Iran. In the United States, two patients tested positive for MERS-CoV in May 2014, each of whom had a history of fever and one or more respiratory symptoms after recent travel from Saudi Arabia (2). No further cases have been reported in the United States despite nationwide surveillance and the testing of 514 patients from 45 states to date.

The majority (504) of the 956 MERS cases were reported to have occurred during March–May 2014 (Figure). However, WHO continues to receive reports of MERS cases, mostly from Saudi Arabia.§ From August 1, 2014, through January 23, 2015, WHO confirmed 102 cases, 97 of which occurred in persons with residence in Saudi Arabia, including three travel-associated cases reported by Austria, Turkey, and Jordan; of the remaining cases, two cases were in persons from Qatar, and three cases were in persons from Oman.

CDC continues to recommend that U.S. travelers to countries in or near the Arabian Peninsula protect themselves from respiratory diseases, including MERS, by washing their hands often and avoiding contact with persons who are ill. If travelers to the region have onset of fever and symptoms of respiratory illness during their trip or within 14 days of returning to the United States, they should seek medical care. They should call ahead to inform their health care provider of their recent travel so that appropriate isolation measures can be taken in health care settings. Health care providers and health departments throughout the United States should continue to consider a diagnosis of MERS-CoV infection in persons who develop fever and respiratory symptoms within 14 days after traveling from countries in or near the Arabian Peninsula, and be prepared to detect and manage cases of MERS.

Recommendations might change and be updated as additional data become available. More detailed travel recommendations related to MERS, including general precautions posted by WHO for anyone visiting farms, markets, barns, or other places where animals are present, are available at http://wwwnc.cdc.gov/travel/notices/alert/coronavirus-arabian-peninsula.

The website also lists more specific WHO recommendations for persons with diabetes, kidney failure, or chronic lung disease, and immunocompromised persons, that include avoiding contact with camels.¶ Guidance on the evaluation of patients for MERS-CoV infection, infection control, home care and isolation, and clinical specimen collection and testing is available on the CDC MERS website at http://www.cdc.gov/coronavirus/mers/index.html.

Treatment is supportive; no specific treatment for MERS-CoV infection is available. WHO has posted guidance for clinical management of MERS patients at

http://www.who.int/csr/disease/coronavirus_infections/InterimGuidance_ClinicalManagement_NovelCoronavirus_11Feb13u.pdf?ua=1.

1Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, CDC; 2Office of the Director, National Center for Immunization and Respiratory Diseases, CDC (Corresponding author: Brian Rha, wif8@cdc.gov, 404-639-3972)

References

1. Zaki AM, van Boheemen S, Bestebroer TM, Osterhaus AD, Fouchier RA. Isolation of a novel coronavirus from a man with pneumonia in Saudi Arabia. N Engl J Med 2012;367:1814–20.
2. Bialek SR, Allen D, Alvarado-Ramy F, et al. First confirmed cases of Middle East respiratory syndrome coronavirus (MERS-CoV) infection in the United States, updated information on the epidemiology of MERS-CoV infection, and guidance for the public, clinicians, and public health authorities—May 2014. MMWR Morb Mortal Wkly Rep 2014;63:431–6.

* Countries considered in the Arabian Peninsula and neighboring include: Bahrain; Iraq; Iran; Israel, the West Bank and Gaza; Jordan; Kuwait; Lebanon; Oman; Qatar; Saudi Arabia; Syria; the United Arab Emirates; and Yemen.

† Confirmatory laboratory testing requires a positive polymerase chain reaction test result on at least two specific genomic targets for MERS-CoV or a single positive target with sequencing on a second.

§ Additional information available at http://www.who.int/csr/don/archive/disease/coronavirus_infections/en.

¶ Additional information available at http://www.who.int/csr/disease/coronavirus_infections/MERS_CoV_RA_20140613.pdf?ua=1.

MMWR: Reduced Protection From This Year’s Flu Vaccine

Photo Credit - CDC PHIL

 

# 9581

 

It is always a bit of a gamble heading into flu season every year since flu vaccines – whose strains must be selected 6 months in advance – may not end up being a very good match for the viruses that are circulating in the fall. Flu viruses mutate over time – and minor strains that seemed insignificant last spring can become dominant by November. 

 

Such is the the case this year, as a recently arrived, `drifted’ H3N2 flu virus (see CDC HAN Advisory On `Drifted’ H3N2 Seasonal Flu Virus) has come on like gang busters over the past few months, beating out the `vaccine’ strain by a factor of 2 to 1. 

 

The result, as you might expect, is that this year’s flu vaccine isn’t as effective as we’d hoped.

 

As we’ve discussed before, flu vaccines – while considered very safe – most years only offer a moderate level of protection against influenza. Their VE (vaccine effectiveness) can vary widely between flu shot recipients, and is often substantially reduced among those older than 65 or those with immune problems.

 

As an example, in October of 2011, in CIDRAP: A Comprehensive Flu Vaccine Effectiveness Meta-Analysis, we saw a major review indicating the TIV (Trivalent Influenza Vaccine) - during 8 of 12 flu seasons (67%) – produced a combined efficacy of only 59% among healthy adults (aged 18–65 years).

 

Despite these moderate success levels, studies have shown the benefits of flu vaccination – even if those benefits aren’t as universal, or predictable, as we’d like.

• Last May, in CDC: Flu Shots Reduce Hospitalizations In The Elderly, we saw a study that suggested that even when a vaccine’s effectiveness is low, it can help attenuate the severity of influenza in the elderly.
• Similarly, over the past couple of years, we’ve seen studies suggesting the flu vaccine may reduce the risk of heart attack and stroke (see JAMA: Flu Vaccine and Cardiovascular Outcomes & Study: Flu Vaccine May Reduce Heart Attack). 

 

So, given its limitations, you may be  wondering why I bother to get the flu vaccine every year and recommend it to others.

 

I consider it cheap insurance, even if the shot only offers a moderate degree of protection. Just as wearing a seatbelt doesn’t guarantee you’ll walk away from a wreck, a flu vaccine won’t guarantee you’ll stay flu-free for the season.  But it can improve your odds. 

 

Some years, obviously, more than others.

 

All of which leads up to today’s MMWR report, which carries a mid-season estimate of the effectiveness of this year’s flu vaccine – one that comes in at an admittedly disappointing 23%.

First the CDC’s press release, followed by a link to the MMWR report.

 

Protection from flu vaccination reduced this season

CDC urges early treatment of severely ill and high-risk patients

A report published in the January 16 Morbidity and Mortality Weekly Report (MMWR) estimates that getting a flu vaccine this season reduced a person’s risk of having to go to the doctor because of flu by 23 percent among people of all ages.

Since CDC began conducting annual flu vaccine effectiveness (VE) studies in 2004-2005, overall estimates for each season have ranged from 10 percent to 60 percent effectiveness in preventing medical visits associated with seasonal influenza illness. The MMWR report says this season’s vaccine offers reduced protection and this underscores the need for additional prevention and treatment efforts this season, including the appropriate use of influenza antiviral medications for treatment.

“Physicians should be aware that all hospitalized patients and all outpatients at high risk for serious complications should be treated as soon as possible with one of three available influenza antiviral medications if influenza is suspected, regardless of a patient’s vaccination status and without waiting for confirmatory testing,” says Joe Bresee, branch chief in CDC’s Influenza Division. “Health care providers should advise patients at high risk to call promptly if they get symptoms of influenza.”

One factor that determines how well a flu vaccine works is the similarity between the flu viruses used in vaccine production and the flu viruses actually circulating. During seasons when vaccine viruses and circulating influenza viruses are well matched, VE between 50 and 60 percent has been observed. H3N2 viruses have been predominant so far this season, but about 70 percent of them have been different or have “drifted” from the H3N2 vaccine virus. This likely accounts for the reduced VE.

Flu viruses change constantly and the drifted H3N2 viruses did not appear until after the vaccine composition for the Northern Hemisphere had been chosen.

Another factor that influences how well the flu vaccine works is the age and health of the person being vaccinated. In general, the flu vaccine works best in young, healthy people and is less effective in people 65 and older. This pattern is reflected in the current season early estimates. VE was highest -- 26 percent -- for children age 6 months through 17 years. While not statistically significant, VE estimates for other age groups were 12 percent for ages 18 to 49 years and 14 percent for people age 50 years and older.

CDC recommends that people get a flu vaccine even during season’s when drifted viruses are circulating because vaccination can still prevent some infections and can reduce severe disease that can lead to hospitalization and death. Also, the flu vaccine is designed to protect against three or four influenza viruses and some of these other viruses may circulate later in the season. Flu activity so far this season has been similar to the 2012-2013 flu season, a “moderately severe” flu season with H3N2 viruses predominating.

Antiviral Supply Update

While manufacturers of antiviral medications have stated that there is no national shortage of antiviral medications at this time, and that there is sufficient product available to meet high demand, there are anecdotal reports of spot shortages of these drugs. CDC’s advice for patients and doctors is that it may be necessary to contact more than one pharmacy to fill a prescription for an antiviral medication. Pharmacies that are having difficulty getting orders filled should contact their distributor or the manufacturer directly.

For large institutional outbreaks this season, CDC is taking new measures to help match demand with supply, working with commercial partners to facilitate filling of large orders of antivirals for long-term care facilities or institutions having difficulty accessing antiviral supplies in outbreak settings. More information is available at http://www.cdc.gov/flu/antivirals/supply

 

 

 

Early Estimates of Seasonal Influenza Vaccine Effectiveness — United States, January 2015

Weekly

January 16, 2015 / 64(01);10-15

Brendan Flannery, PhD1, Jessie Clippard, MPH1, Richard K. Zimmerman, MD2, Mary Patricia Nowalk, PhD2, Michael L. Jackson, PhD3, Lisa A. Jackson, MD3, Arnold S. Monto, MD4, Joshua G. Petrie, MPH4, Huong Q. McLean, PhD5, Edward A. Belongia, MD5, Manjusha Gaglani, MBBS6, LaShondra Berman, MS1, Angie Foust, MA1, Wendy Sessions, MPH1, Swathi N. Thaker, PhD1, Sarah Spencer, PhD1, Alicia M. Fry, MD1 (Author affiliations at end of text)

In the United States, annual vaccination against seasonal influenza is recommended for all persons aged ≥6 months (1). Each season since 2004–05, CDC has estimated the effectiveness of seasonal influenza vaccine in preventing medically attended acute respiratory illness (ARI) associated with laboratory-confirmed influenza. This season, early estimates of influenza vaccine effectiveness are possible because of widespread, early circulation of influenza viruses.

By January 3, 2015, 46 states were experiencing widespread flu activity, with predominance of influenza A (H3N2) viruses (2). This report presents an initial estimate of seasonal influenza vaccine effectiveness at preventing laboratory-confirmed influenza virus infection associated with medically attended ARI based on data from 2,321 children and adults enrolled in the U.S. Influenza Vaccine Effectiveness Network (Flu VE) during November 10, 2014–January 2, 2015. During this period, overall vaccine effectiveness (VE) (adjusted for study site, age, sex, race/ethnicity, self-rated health, and days from illness onset to enrollment) against laboratory-confirmed influenza associated with medically attended ARI was 23% (95% confidence interval [CI] = 8%–36%). Most influenza infections were due to A (H3N2) viruses.

This interim VE estimate is relatively low compared with previous seasons when circulating viruses and vaccine viruses were well-matched and likely reflects the fact that more than two-thirds of circulating A (H3N2) viruses are antigenically and genetically different (drifted) from the A (H3N2) vaccine component of 2014–15 Northern Hemisphere seasonal influenza vaccines (2). These early, low VE estimates underscore the need for ongoing influenza prevention and treatment measures. CDC continues to recommend influenza vaccination because the vaccine can still prevent some infections with the currently circulating A (H3N2) viruses as well as other viruses that might circulate later in the season, including influenza B viruses. Even when VE is reduced, vaccination still prevents some illness and serious influenza-related complications, including thousands of hospitalizations and deaths (3). Persons aged ≥6 months who have not yet been vaccinated this season should be vaccinated, including persons who might already have been ill with influenza this season.

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MMWR Early Release: Multiple Dispatches On Ebola

Credit CDC PHIL

 

# 9324

 

I haven’t had time to read them yet, but the CDC’s MMWR has published the following half dozen Ebola-centric reports today.

 

MMWR Early Release

November 14, 2014 / Vol. 63 / Early Release

Evidence for a Decrease in Transmission of Ebola Virus — Lofa County, Liberia, June 8–November 1, 2014
Download Issue

Evidence for Declining Numbers of Ebola Cases — Montserrado County, Liberia, June–October 2014
Download Issue

Ebola Virus Disease Cases Among Health Care Workers Not Working in Ebola Treatment Units — Liberia, June–August, 2014
Download Issue

Ebola Epidemic — Liberia, March–October 2014
Download Issue

Ebola Virus Disease Cluster in the United States — Dallas County, Texas, 2014
Download Issue

Response to Importation of a Case of Ebola Virus Disease — Ohio, October 2014
Download Issue

MMWR Early Release: Ebola Update In West Africa – Oct 28th

 

# 9260

 

From the CDC’s MMWR, an update on the Ebola outbreak in West Africa.  Follow the link for the accompanying maps and charts.

 

Update: Ebola Virus Disease Outbreak — West Africa, October 2014

Early Release

October 28, 2014 / 63(Early Release);1-4

Incident Management System Ebola Epidemiology Team, CDC; Guinea Interministerial Committee for Response Against the Ebola Virus; CDC Guinea Response Team; Liberia Ministry of Health and Social Welfare; CDC Liberia Response Team; Sierra Leone Ministry of Health and Sanitation; CDC Sierra Leone Response Team; Viral Special Pathogens Branch, National Center for Emerging and Zoonotic Infectious Diseases, CDC

CDC is assisting ministries of health and working with other organizations to control and end the ongoing outbreak of Ebola virus disease (Ebola) in West Africa (1). The updated data in this report were compiled from situation reports from the Guinea Interministerial Committee for Response Against the Ebola Virus and the World Health Organization, the Liberia Ministry of Health and Social Welfare, and the Sierra Leone Ministry of Health and Sanitation. Total case counts include all suspected, probable, and confirmed cases as defined by each country. These data reflect reported cases, which make up an unknown proportion of all actual cases and reporting delays that vary from country to country.

According to the latest World Health Organization update as of October 22, 2014 (2), a total of 9,911 Ebola cases have been reported as of October 19 from three highly affected West African countries (Guinea, Liberia, and Sierra Leone) (Figure 1). The highest reported case counts were from Liberia (4,665 cases), followed by Sierra Leone (3,706) and Guinea (1,540).

The geographic distribution of the number of Ebola cases reported during September 28–October 18 changed from the distribution of cases reported during August 31–September 23 (3), when counts were highest in the areas where Liberia, Sierra Leone, and Guinea meet. Counts of Ebola cases reported during September 28–October 18 were highest in the area around Monrovia and in the district of Bong, Liberia; the Freetown area and the northwest districts of Sierra Leone; and the district of Macenta, Guinea (Figure 2).

The map of the cumulative incidence of Ebola, as of October 18, indicates that the highest incidence rate (>100 cases per 100,000 population) was reported by two districts in Guinea (Guéckédou and Macenta), five districts in Liberia (Bomi, Bong, Lofa, Margibi, and Montserrado), and four districts in Sierra Leone (Bombali, Kailahun, Kenema, and Port Loko) (Figure 3).

The latest updates on the 2014 Ebola outbreak in West Africa, including case counts, are available at http://www.cdc.gov/vhf/ebola/outbreaks/guinea/index.html. The most up-to-date clinical guidelines on the 2014 Ebola outbreak in West Africa are available at http://www.cdc.gov/vhf/ebola/hcp/index.html 

(Continue.  . .)

Three Early Release MMWRs On The Ebola Outbreak

 

 

# 9127

 

The CDC has released a series of three early release MMWRs today on the Ebola outbreak in Africa.  One on the ongoing outbreak in Liberia, Guinea and Sierra Leone, while the other two concentrate on the rapid responses to Nigeria’s and Senegal’s imported cases. 

Below you’ll find links, and the CDC’s capsule descriptions for each document.

 

MMWR Early Release

PDF

Ebola Virus Disease Outbreak — West Africa, September 2014
Incident Management System Ebola Epidemiology Team, CDC; Ministries of Health of Guinea, Sierra Leone, Liberia, Nigeria, and Senegal; Viral Special Pathogens Branch, National Center for Emerging and Zoonotic Infectious Diseases, CDC.
MMWR 2014;63(Early Release):1-2

Updated data on the Ebola virus disease outbreak in West Africa indicate that, as of September 23, a total of 6,574 cases had been reported from five West Africa countries (Guinea, Liberia, Nigeria, Senegal, and Sierra Leone). The highest reported case counts were from Liberia (3,458 cases), Sierra Leone (2,021), and Guinea (1,074).

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PDF

Ebola Virus Disease Outbreak — Nigeria, July–September 2014
Faisal Shuaib, DrPH, Rajni Gunnala, MD, Emmanuel O. Musa, MBBS, et al.
MMWR 2014;63(Early Release):1-6
On July 20, an acutely ill traveler from Liberia arrived at the international airport in Lagos, Nigeria, and was confirmed to have Ebola virus disease after being admitted to a private hospital. The Federal Ministry of Health, with the Lagos State government and international partners, activated an Ebola Incident Management Center as a precursor to the current Emergency Operations Center to rapidly respond to this outbreak. The index patient died on July 25; as of September 24, there were 19 laboratory-confirmed Ebola cases and one probable case in two states, with 894 contacts identified and followed during the response.

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PDF

Importation and Containment of Ebola Virus Disease — Senegal, August–September 2014
Kelsey Mirkovic, PhD, Julie Thwing, MD, Papa Amadou Diack, MD.
MMWR 2014;63(Early Release):1-2
On August 29, 2014, Senegal confirmed its first case of Ebola virus disease in a Guinean man, aged 21 years, who had traveled from Guinea to Dakar, Senegal, in mid-August to visit family. Senegalese medical and public health personnel were alerted about this patient after public health staff in Guinea contacted his family in Senegal on August 27. This report describes the investigation and containment measures that followed.

 

The CDC has also published a the following statement, summarizing what (for now, at least) appears to have been a successful containment campaign in Senegal and Nigeria. 

 

 

Ebola outbreak is nearing possible end in Nigeria

Strong emergency operations center, polio eradication experience keys to success

The Ebola outbreak in Nigeria appears to be nearing a possible end thanks to a rapid response coordinated by Nigeria’s Emergency Operations Center with assistance from international partners, including the U.S. Centers for Disease Control and Prevention (CDC). The official end to an Ebola outbreak comes when two of the 21-day incubation periods for Ebola virus have elapsed without any new cases.

During the outbreak there were 19 laboratory-confirmed and one probable Ebola cases in two Nigerian states. Nearly 900 patient contacts were identified and followed; all but three have completed 21 days of follow-up without Ebola symptoms.  There have been no new cases since August 31 and the last three patient contacts will exit their 21-day follow-up on October 2 – strongly suggesting the outbreak in Nigeria has been contained.  A report on Nigeria’s response to the outbreak appears in a Sept. 30 early release issue of CDC’s Morbidity and Mortality Weekly Report (MMWR).

"Although Nigeria isn’t completely out of the woods, their extensive response to a single case of Ebola shows that control is possible with rapid, focused interventions,” said CDC Director Tom Frieden, M.D, M.P.H. “Countries throughout the region as well as Nigeria need to take rapid steps to prepare for possible cases of Ebola in order to prevent outbreaks in their country.”

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Given the gravity of the situation in the three hardest hit nations of Guinea, Liberia, and Sierra Leone the apparent successful containment of Ebola in Nigeria and Senegal provides some welcome good news.

MMWR: Updated Preparedness and Response Framework for Influenza Pandemics

Hypothetical Influenza Outbreak Curve

 

# 9016

 

Last year the World Health Organization Unveiled New Pandemic Guidance, replacing their old pandemic phase system (3 pre-pandemic phases+ 3 pandemic phases+2 post-pandemic phases) with a more streamlined 4-phase system.

 

As you’ll note, this system utilizes `soft’ transitions from one phase to the next, indicating that changes may happen slowly, or at different rates in different regions, rather than abruptly.  The interpandemic phase is a time for preparedness, while the response is ramped up once an alert is sounded.

 

Yesterday the CDC published a new pandemic preparedness and response framework that aligns the CDC’s pandemic phase system more closely with the WHO’s, although there are some differences.

 

According the the CDC, this update `provides greater detail and clarity regarding the potential timing of key decisions and actions aimed at slowing the spread and mitigating the impact of an emerging pandemic’.

This is a fairly lengthy update, and so I’ve only posted the summary.  Follow the link below to read it in its entirety.  When you return, I’ll have a bit more.

 

Updated Preparedness and Response Framework for Influenza Pandemics

Recommendations and Reports

September 26, 2014 / 63(RR06);1-9

Prepared by Rachel Holloway1, Sonja A. Rasmussen, MD1, Stephanie Zaza, MD2, Nancy J. Cox, PhD3, Daniel B. Jernigan, MD3, with the Influenza Pandemic Framework Workgroup

1Influenza Coordination Unit, Office of Infectious Diseases

2Division of Adolescent and School Health, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention

3Influenza Division, National Center for Immunization and Respiratory Diseases

Corresponding preparer: Sonja A. Rasmussen, MD, CDC. Telephone: 404-639-2297; E-mail: srasmussen@cdc.gov.

Summary

The complexities of planning for and responding to the emergence of novel influenza viruses emphasize the need for systematic frameworks to describe the progression of the event; weigh the risk of emergence and potential public health impact; evaluate transmissibility, antiviral resistance, and severity; and make decisions about interventions. On the basis of experience from recent influenza responses, CDC has updated its framework to describe influenza pandemic progression using six intervals (two prepandemic and four pandemic intervals) and eight domains.

his updated framework can be used for influenza pandemic planning and serves as recommendations for risk assessment, decision-making, and action in the United States. The updated framework replaces the U.S. federal government stages from the 2006 implementation plan for the National Strategy for Pandemic Influenza (US Homeland Security Council. National strategy for pandemic influenza: implementation plan. Washington, DC: US Homeland Security Council; 2006. Available at http://www.flu.gov/planning-preparedness/federal/pandemic-influenza-implementation.pdf ).

The six intervals of the updated framework are as follows: 1) investigation of cases of novel influenza, 2) recognition of increased potential for ongoing transmission, 3) initiation of a pandemic wave, 4) acceleration of a pandemic wave, 5) deceleration of a pandemic wave, and 6) preparation for future pandemic waves. The following eight domains are used to organize response efforts within each interval: incident management, surveillance and epidemiology, laboratory, community mitigation, medical care and countermeasures, vaccine, risk communications, and state/local coordination.

Compared with the previous U.S. government stages, this updated framework provides greater detail and clarity regarding the potential timing of key decisions and actions aimed at slowing the spread and mitigating the impact of an emerging pandemic. Use of this updated framework is anticipated to improve pandemic preparedness and response in the United States. Activities and decisions during a response are event-specific. These intervals serve as a reference for public health decision-making by federal, state, and local health authorities in the United States during an influenza pandemic and are not meant to be prescriptive or comprehensive. This framework incorporates information from newly developed tools for pandemic planning and response, including the Influenza Risk Assessment Tool and the Pandemic Severity Assessment Framework, and has been aligned with the pandemic phases restructured in 2013 by the World Health Organization.

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Despite their (mostly cosmetic) differences, both the CDC and the WHO stress that the time before the next pandemic strikes is a time for preparedness.   While there’s a perception that pandemics only come around every few decades, and most are – if not mild, at least manageable -  there are no guarantees how long it will be before the next severe one arrives.

Earlier this month, in NPM14: Because Pandemics Happen I wrote about both the history of pandemics, and the concerns held by some of the highest offices in the land over the potential impact of the next pandemic.

 

Many agencies consider pandemics to be among the top threats to national and global security.

 
While most people think that their state or federal government are prepared to handle the next pandemic, the Feds continue to remind us that they can’t handle a major disaster – including a pandemic – without the help of everyone involved.

 

Which is why September of every year is declared National Preparedness Month, where  FEMA and Ready.gov encourage everyone to prepare for a variety of disaster situations.  

 

And it’s not just me saying it.  This from Flu.gov.

 

Pandemic Flu

The federal government cannot prepare for or respond to the challenge of a flu pandemic alone. Your community can develop strategies that reduce the impact and spread of pandemic flu.

Faith-Based & Community Organizations Pandemic Influenza Preparedness Checklist (PDF – 68.91 KB)

Lista de Preparacion para una Pandemia de Gripe Tanto para Organizaciones Comunitarias como Religiosas (PDF – 268 KB)

Community Strategy for Pandemic Influenza Mitigation (PDF – 10.3 MB)

Plan Now to Be Ready for the Next Flu Pandemic (PDF – 213.55 KB)

The Next Flu Pandemic: What to Expect (PDF – 226.83 KB) (excerpts below)

Their advice (and this is for before a pandemic threat becomes imminent).

 

CDC Statements On MMWR Ebola Estimates

 

# 9006

 

Yesterday’s MMWR  worst case estimate of between 550,000 and 1.4 million Ebola cases in Liberia and Sierra Leone by the end of January - if interventions are not implemented - (see MMWR: Estimating The Future Number of Cases In The Ebola Epidemic) has garnered predictable headlines while the CDC’s caveats regarding the interpretation of  these numbers generally appears much further down the page.

 

CDC Director Dr. Thomas Frieden has been quick to point out that this report is based on `month-old data’ and that it doesn’t take into account recent and future interventions, but the `hook’  for most overnight reportage reads along the lines of:                                                                            

CDC estimates 1.4 million Ebola cases by Jan 

or 

Ebola Cases Could Reach 1.4 Million Within Four Months

 

The World Health Organization meanwhile has provided a far more subdued short-term projection that if interventions aren’t initiated the number of cases could climb to 20,000 by early November (see NEJM Ebola Virus Disease in West Africa — the First 9 Months and Forward Projections).

 

Both the CDC and WHO have expressed optimism that the `worst-case scenario’ can be avoided by the surge of international assistance now headed to the region. 

 

That said, rarely do major disaster response operations go as well as hoped, and the challenges presented by this crisis are unprecedented.  How much optimism is warranted is something we won’t know for several months.  

 

The CDC has released some ancillary documents for this MMWR report, including a statement from CDC Director Frieden and a Fact Sheet on the findings. Since these sorts of provisos often get short shrift in the media, I’ve provided links and excerpts below:

 

 

Media Statement

For Immediate Release: Tuesday, September 23, 2014
Contact: Media Relations
(404) 639-3286

CDC Statement from the Director

Ebola is a critical issue for the world community. This week’s meetings in NY and Washington are a critical opportunity for increased international commitments and, more importantly, action.

The Ebola case estimates published today in the MMWR are based on data from August and reflect a moment in time before recent significant increases in efforts to improve treatment and isolation. They do not account for actions taken or planned since August by the United States and the international community. We anticipate that these actions will slow the spread of the epidemic.

The Ebola Response model is an important tool for people working to stop Ebola. It provides the ability to help Ebola response planners make more informed decisions on the emergency response to help bring the outbreak under control – and what can happen if these resources are not brought to bear quickly.

The model shows that there are severe costs of delay, and the need for increased resources and immediate and ongoing action by the international community.

It is still possible to reverse the epidemic, and we believe this can be done if a sufficient number of all patients are effectively isolated, either in Ebola Treatment Units or in other settings, such as community-based or home care.

Once a sufficient number of Ebola patients are isolated, cases will decline very rapidly – almost as rapidly as they rose.

Tom Frieden, M.D., M.P.H.
Director, Centers for Disease Control and Prevention

 

Excerpts from the Fact sheet:

 

New Modeling Tool for Response to Ebola Virus Disease

Ebola Response Modeling Tool
CDC has developed a dynamic modeling tool called Ebola Response that allows for estimations of projected cases over time in Liberia and Sierra Leone. The Ebola Response modeling tool was used to construct scenarios to illustrate how control and prevention interventions can slow and eventually stop the Ebola epidemic. Importantly, it can help planners make more informed decisions about emergency response resources to help bring the outbreak under control. It allows input of data reflective of the current situation on the ground in affected countries and communities. The Ebola Response modeling tool is intended to help local governments and international responders generate short-term estimates of the Ebola situations in countries, districts, and villages. The tool, in the form of a Microsoft Excel spreadsheet, will be freely available online.

<SNIP>

Projecting Ebola Case Estimates
Published today in MMWR, CDC used the Ebola Response modeling tool to calculate Ebola cases through mid- January in Sierra Leone and Liberia, providing an example of how this tool can be used. The MMWR estimates a range of between 550,000 and 1.4 million cases by January 20, 2015. The top range of the case estimate, 1.4 million, is explained by the model’s assumption that cases are significantly underreported by a factor of 2.5. It is essential to note that these numbers reflect a moment in time based on scientific and epidemiological data available in August, which did not account for the ongoing U.S. government Ebola relief effort. The numbers do not reflect current conditions. Modeling suggests that extensive, immediate actions – such as those already started – can bring the epidemic to a tipping point to start a rapid decline in cases.

The most important part of the report describes the potential effect of public health actions. The news is encouraging. If we do nothing, things could become much worse. If we take the actions that are planned, things will still be very hard, but we can stop Ebola. The United States and its partners are taking action every day.

Using the Ebola Response modeling tool, we see that the epidemic can begin to be controlled when individuals with Ebola are effectively isolated in Ebola treatment units (ETUs) or in isolation settings in which there is a reduced risk of Ebola transmission. The model also shows a benefit when safe burial practices are implemented that eliminate exposure of healthy individuals to the bodily fluids of the deceased, which often occurs with the use of traditional burial practices. The model indicates that once a tipping point is reached, cases will decline about as rapidly as they had increased. Of note, gains below such a tipping point can also significantly reduce cases.

MMWR: Estimating The Future Number of Cases In The Ebola Epidemic

 

Credit CDC PHIL

 

# 9005

 

 

The much anticipated (and already telegraphed) MMWR report modeling the possible future number of Ebola cases in Liberia and Sierra Leone has now been published, and they paint a dire picture where between 550,000 to 1.4 million infections could result over the next four months if interventions are not successful.  

 

At the same time the CDC held a press conference where Director Dr. Thomas Frieden warned that these numbers are based on `month-old data’, don’t reflect current and future progress in controlling the outbreak, and that  these `worst-case’ scenarios are unlikely to unfold.

 

With a range of possibilities running from a few tens of thousands of cases to well over a million, everything hinges on the speed and effectiveness of international efforts to mitigate the spread of this virus.  And while one remains hopeful the tide in that endeavor has begun to turn, it is far too soon to know how much impact they will ultimately have, and how soon they will gain traction.

 

Which means  - where we really are, and how bad this outbreak becomes - is likely to remain uncertain for some weeks to come.

 

Given the vagueness of today’s case counts, I haven’t found any compelling reason to embrace any single one of these recently published models over the others.  That said, I don’t discount any of them, either. 

 

My personal take is that things on the ground are probably worse than we know, and it is going to take a herculean international effort – and more than a bit of luck – if this epidemic is to be brought under control anytime soon. 

 

Follow the link to read the full MMWR report.

 

 

Estimating the Future Number of Cases in the Ebola Epidemic — Liberia and Sierra Leone, 2014–2015

Early Release

September 23, 2014 / 63(Early Release);1-4

Martin I. Meltzer, PhD1, Charisma Y. Atkins, MPH1, Scott Santibanez, MD1, Barbara Knust, DVM2, Brett W. Petersen D2, Elizabeth D. Ervin, MPH2, Stuart T. Nichol, Ph.D2 , Inger K. Damon, MD, PhD2, Michael L. Washington, PhD1

Corresponding author: Martin I. Meltzer, National Center for Emerging and Zoonotic Infectious Diseases, CDC. E-mail: qzm4@cdc.gov; Telephone: 404-639-7778.

Abstract

The first cases of the current West African epidemic of Ebola virus disease (hereafter referred to as Ebola) were reported on March 22, 2014, with a report of 49 cases in Guinea. By August 31, 2014, a total of 3,685 probable, confirmed, and suspected cases in West Africa had been reported. To aid in planning for additional disease-control efforts, CDC constructed a modeling tool called EbolaResponse to provide estimates of the potential number of future cases. If trends continue without scale-up of effective interventions, by September 30, 2014, Sierra Leone and Liberia will have a total of approximately 8,000 Ebola cases.

A potential underreporting correction factor of 2.5 also was calculated. Using this correction factor, the model estimates that approximately 21,000 total cases will have occurred in Liberia and Sierra Leone by September 30, 2014. Reported cases in Liberia are doubling every 15–20 days, and those in Sierra Leone are doubling every 30–40 days. The EbolaResponse modeling tool also was used to estimate how control and prevention interventions can slow and eventually stop the epidemic.

In a hypothetical scenario, the epidemic begins to decrease and eventually end if approximately 70% of persons with Ebola are in medical care facilities or Ebola treatment units (ETUs) or, when these settings are at capacity, in a non-ETU setting such that there is a reduced risk for disease transmission (including safe burial when needed). In another hypothetical scenario, every 30-day delay in increasing the percentage of patients in ETUs to 70% was associated with an approximate tripling in the number of daily cases that occur at the peak of the epidemic (however, the epidemic still eventually ends). Officials have developed a plan to rapidly increase ETU capacities and also are developing innovative methods that can be quickly scaled up to isolate patients in non-ETU settings in a way that can help disrupt Ebola transmission in communities. The U.S. government and international organizations recently announced commitments to support these measures. As these measures are rapidly implemented and sustained, the higher projections presented in this report become very unlikely.

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MMWR: CDC Interim Guidance On Polio Vaccination For Travelers To/From Countries With WPV

Credit MMWR

# 8811

 

 

Two months ago (May 5th) the World Health Organization -  after convening a meeting of their Emergency Committee on the recent spike in polio cases in the Middle East and parts of Africa- Declared  Polio Spread A Public Health Emergency Of International Concern (PHEIC).

 

A month later, the CDC published a HAN (Health Alert Network) Advisory with New Vaccination Requirements For Travel To Countries With Active Polio.

 

Yesterday the MMWR fleshed out these new vaccine requirements in an early release called:

 

Interim CDC Guidance for Polio Vaccination for Travel to and from Countries Affected by Wild Poliovirus

Early Release

July 7, 2014 / 63(Early Release);1-4

Gregory S. Wallace, MD1, Jane F. Seward, MBBS1, Mark A. Pallansch, PhD1 (Author affiliations at end of text)

(Excerpt)

Vaccine Recommendations and Requirements

Advisory Committee on Immunization Practices (ACIP) and CDC recommendations are evidence-based and provide public health recommendations to the general public on the basis of the best available epidemiological and scientific data to prevent poliovirus infection. This includes recommendations for travelers visiting countries with WPV circulation in the last 12 months or countries and provinces where they will be in situations with a high risk for exposure to persons with imported poliovirus infection.

Three countries are still endemic for polio (Afghanistan, Nigeria, and Pakistan). Countries where WPV has circulated during the previous 12 months include those endemic countries and those with polio outbreaks or environmental evidence of active WPV circulation during this time (Cameroon, Ethiopia, Equatorial Guinea, Iraq, Israel, Somalia, and Syria). Travelers working in health-care settings, refugee camps, or other humanitarian aid settings in these and neighboring countries might be at particular risk for exposure to WPV.

Recommendations for vaccination under the International Health Regulations differ from ACIP and CDC recommendations and include exit requirements for proof of polio vaccination when leaving the country at borders or through airports. If implemented by a country, these requirements could be mandatory and are intended to prevent exportation of WPV.

Vaccine Recommendations for Travelers to Countries with WPV Circulation

Persons at greatest risk for acquiring polio are unvaccinated persons. In the United States, infants and children should be vaccinated against polio as part of a routine immunization series. Before traveling to areas with WPV circulation, all travelers should ensure that they have completed the recommended age-appropriate polio vaccine series and have received a booster dose, if necessary.*

Infants and Children

In the United States, all infants and children should receive 4 doses of IPV at ages 2, 4, and 6–18 months and 4–6 years (10). The final dose should be administered at age ≥4 years, regardless of the number of previous doses, and should be given ≥6 months after the previous dose. A fourth dose in the routine IPV series is not necessary if the third dose was administered at age ≥4 years and ≥6 months after the previous dose (11). Infants and children traveling to areas where there has been WPV circulation in the last 12 months should be vaccinated according to the routine schedule. If the routine series cannot be administered within the recommended intervals before protection is needed, an accelerated schedule can be used as follows: 1) the first dose should be given to infants aged ≥6 weeks, 2) the second and third doses should be administered ≥4 weeks after the previous doses, and 3) the minimum interval between the third and fourth doses is 6 months.

If the age-appropriate series is not completed before departure, the remaining IPV doses to complete a full series should be administered when feasible, at the intervals recommended for the accelerated schedule. If doses are needed while residing in the affected country, the polio vaccine that is available (IPV or OPV) may be administered.

Adults

Adults, who are traveling to areas where there has been WPV circulation in the last 12 months and who are unvaccinated, incompletely vaccinated, or whose vaccination status is unknown should receive a series of 3 doses: 2 doses of IPV administered at an interval of 4–8 weeks; a third dose should be administered 6–12 months after the second. If 3 doses of IPV cannot be administered within the recommended intervals before protection is needed, the following alternatives are recommended:

• If >8 weeks are available before protection is needed, 3 doses of IPV should be administered ≥4 weeks apart.
• If <8 weeks but >4 weeks are available before protection is needed, 2 doses of IPV should be administered ≥4 weeks apart.
• If <4 weeks are available before protection is needed, a single dose of IPV is recommended.

If <3 doses are administered, the remaining IPV doses to complete a 3-dose series should be administered when feasible, at appropriate intervals, if the person remains at increased risk for poliovirus exposure. If doses are needed while residing in the affected country, the polio vaccine that is available (IPV or OPV) may be administered.

Adults who have completed a routine series of polio vaccine are considered to have lifelong immunity to poliovirus, but data are lacking (12). As a precaution, persons aged ≥18 years who are traveling to areas where there has been WPV circulation in the last 12 months and who have received a routine series with either IPV or OPV in childhood should receive another dose of IPV before departure. For adults, available data do not indicate the need for more than a single lifetime booster dose with IPV.

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