More ICEID Coverage From CIDRAP

 

 

 

# 4726

 

 

 

From the ICEID 2010 Conference going on this week in Atlanta, Lisa Schnirring of CIDRAP News has been keeping us updated.   You can find all of her reports from the conference here.

 

Last night Lisa filed a report on research into protecting workers from airborne pathogens - particularly in the health care environment – and dealing with workplace anthrax contamination.

 

Last year, the debate over how to protect HCWs sprung to the forefront when, early on in the pandemic, it became apparent that there were too few N95 masks stockpiled.

 

Nurses Protest Lack Of PPE’s

Report: Nurses File Complaint Over Lack Of PPE

California Nurses Association Statement On Lack Of PPE

 

Fortunately, the novel H1N1 virus did not turn out to be as virulent as SARS, or H5N1, and the crisis gradually subsided.

We may not be so lucky with the next airborne pathogen.

 

But safety issues go beyond PPEs (Personal Protective Equipment) like N95 masks. As the following report tells us, we’ve a serious shortage of negative pressure isolation rooms in this country as well.

 

 

 

Research continues on shielding workers from airborne pathogens

Lisa Schnirring Staff Writer

Jul 14, 2010 ATLANTA (CIDRAP News) – The early response to the H1N1 pandemic exposed ongoing sore points regarding protection of workers in healthcare and other settings during epidemics or bioterrorist attacks, and federal researchers today highlighted current efforts to address some of the concerns.

 

They covered emerging issues such as a need for more surge capacity for airborne-pathogen isolation units and possible enhancements for guidance on responding to anthrax attacks in workplace settings. The experts presented their updates in a panel discussion at the International Conference on Emerging Infectious Diseases (ICEID).

 

(Continue . . . )

 

 

CIDRAP also has another mini-roundup of some of the slide presentation abstracts from the conference.

 

ICEID NEWS SCAN: School closures, pneumonia and flu deaths, raw milk demand, sprout outbreaks

More From the ICEID Conference

 

 

 

# 4723

 

Being a semi-recovered Lymie (no active infection, but some residual sequelae), I’ve a deep interest in tick borne diseases like Lyme, Erlichiosis, STARI, Babeisis, and RMSF (Rocky Mountain Spotted Fever).

 

In recent years we’ve seen these – and other – tick borne illnesses show up in regions of the country, and the world, where they’ve not been seen before.

 

Additionally, mosquito borne illnesses such as Dengue, Malaria, Chikungunya, and Yellow Fever are threats in many parts of the world.  Dengue Fever even returned to Florida last year – after an absence of six decades.

 

While a good deal of this year’s ICEID 2010 conference has understandably dealt with influenza, it isn’t by any means the only important Emerging Infectious Disease topic under discussion.

 

A brief listing, therefore, of some of the vector borne disease ICEID 2010 abstracts available from the EID Journal, followed by an update from CIDRAP.   

 

You’ll find these abstracts about 3/4ths down the PDF.

 

(Click link to open)

 

Vectorborne Diseases and Climate Change
Acute Versus Paired Serology for La Crosse Encephalitis Surveillance

R. Murphree, J. Dunn, W. Schaffner, T. Jones

 

 

Powassan Encephalitis in Minnesota: An Emerging Tick-Borne Disease in Ixodes scapularis–Endemic Areas

M. Kemperman, A. DeVries, D. Neitzel, C. Lees, K. Smith, G. Liu, A. Hoogerland, S. Kline, N. Fossland, C. Schrock, R. Lynfield

 

 

Rocky Mountain Spotted Fever Associated with Rhipicephalus sanguineus Ticks: From Emergence to Establishment of an Enzootic Focus in the United States

J. McQuiston, C. Levy, M. Traeger, S. Piontkowski, T. Stewart, W. Nicholson, J. Regan

 

 

Changing Epidemiology of Ixodes scapularis–Borne Diseases in Minnesota, 1996–2007

M. Kemperman, D. Neitzel, G. Liu, K. Smith; Minnesota Department of Health, Saint Paul, MN

 

 

Investigation of Dengue Fever Outbreak in Key West, Florida, 2009

C. Blackmore, E. Radke1, C. Gregory, K. Weis, E. Sauber-Schatz, G. Gallagher, E. Hunsperger, K. Tomashek, B. Biggerstaff, L. Stark, C. Munoz

 

 

Satellite Remote Sensing of West Nile Virus Risk in the Northern Great Plains

M. Wimberly, T. Chuang, G. Henebry

 

 

Lisa Schnirring of CIDRAP News is in Atlanta this week covering this conference, and is filing reports which you can access HERE.

 

As of now, here are the CIDRAP reports available.

 

ICEID NEWS SCAN: Thermal scanners, asymptomatic H1N1 in HCWs, pandemic vaccine wariness, dengue in Florida, foodborne disease patterns

ICEID COVERAGE
Experts air H1N1 lessons, other disease challenges

ICEID NEWS SCAN: Salsa and sickness, hand-hygiene gap, West Nile antibodies, 1918 pandemic

CIDRAP Coverage Of ICEID 2010

 

 

# 4721

 

 

Lisa Schnirring, staff writer for CIDRAP, has their first report on the ICEID 2010 conference going on in Atlanta this week.   

 

I’ve just reproduced the opening paragraphs, follow the link to read it in its entirety.  And check back to CIDRAP’s Latest News Page for additional updates and stories.

 

 

Experts air H1N1 lessons, other disease challenges

Lisa Schnirring Staff Writer

Jul 12, 2010 – ATLANTA (CIDRAP News) – The vital role of preparedness, from diagnostic testing to stockpiling of antiviral medications, was one of the most important lessons from assessments of the world's response to the H1N1 influenza pandemic, the World Health Organization's (WHO's) top flu expert told an international infectious diseases conference yesterday.

 

Keiji Fukuda, MD, special influenza adviser to WHO Director-General Margaret Chan, said the revised International Health Regulations (IHRs), adopted by the World Health Assembly after the 2004 reemergence of the H5N1 avian influenza virus, pushed countries to be more open when the first novel H1N1 cases emerged last spring in California and Mexico.

 

"It set a critical precedent and set a tone that was important for the whole global response," Fukuda said in a keynote address on lessons of the H1N1 pandemic at the opening session of the International Conference on Emerging Infectious Diseases (ICEID).

(Continue . . .)

ICEID: Asymptomatic H1N1 in HCWs

 

 

# 4720

 

 

Another of the presentations scheduled for the ICEID 2010 conference this week that caught my eye is this one on asymptomatic H1N1 infections among Health Care Workers in Japan.

 

 

 

Asymptomatic Infection of Influenza A(H1N1) 2009 Pandemic Virus among Japanese Healthcare Workers

(note: It’s about 1/3rd down the pdf)

A. Suzuki, T. Odagiri, T. Okada, K. Shimabukuro, A. hno, I. Khandaker, R. Sawayama, Y. Furuse, K. Kawamura , H. Oshitani

First, the abstract, then a few thoughts as to why this one might be particularly important.

Background:  One of the limitations of the current influenza surveillance is the detection of
asymptomatic cases, which play important role in disease transmission. It is difficult to detect
asymptomatic cases even with sensitive molecular methods, and a retrospective serological test is the
method to confirm.

 

The asymptomatic infection among healthcare worker may the big issues in terms of infection control, but its occurrence is unknown. We conducted sero-epidemiology study to elucidate the prevalence of asymptomatic infection of influenza A(H1N1) pandemic virus in a cohort of healthcare workers in Japan.

 

Methods: One hundred forty healthcare workers, including 25 pediatricians, in 18 private pediatric outpatient clinics in Sendai, Japan, have been participating in the cohort study to monitor
the incidence of influenza infection during pandemic.Serum was collected between 38th and 42nd epidemiological week, the early stage of community transmission in Sendai.

 

Hemagglutination inhibition (HI) test was used to measure the antibody against pandemic influenza. Purified hemagglutinin of A/California/07/2009 pdm was used as the antigen for HI test, and was kindly provided by National Institute for Infectious Disease in Tokyo, Japan.

 

All participants were asked to fill the questionnaire on history of influenza-like illness from May 2009 to the day of sampling. Paired-serums of symptomatic laboratory-confirmed cases in this cohort study were used as the reference for HI titer.

 

Results: Among 123 participants, 33 (27%) had HI antibody titer below 1:10, 39 (32%) had 1:10, 16 (13%) had 1:20, 18 (15%) had 1:40, 11 (9%) had 1:80, 4 (3%) had 1:160, and 2 (1%) had 1:320.

All laboratory-confirmed cases had HI titer higher than 1:160 in convalescence phase serum. Only one case reported to have influenza-like illness after May 2009 and most of them were asymptomatic.By stratification by the job title, medical doctors had highest attack rate.

 

Conclusion: We were able to confirm the high prevalence of infected cases, as well as asymptomatic cases, among healthcare workers in Japan despite of the fact that most of them wearing surgical or N95 masks.

 

Alternative approach should be taken place in healthcare facilities to protect workers from influenza infection.

 

 

 

Ok, for those not up to speed on antibody titer values, a seropositive rate is generally defined as ≥ 1:40.

 

So while this abstract is a bit terse, among the 123 participants of this study, 88 (71.5%) appear to have been seronegative, while as many as 35 (28.5%) had antibody titers that met that criteria for having been infected by pandemic H1N1.

 

This study is interesting for a number of reasons, and not just for the incidence of asymptomatic cases.

 

First, while attack rates of 28% have been documented in school age children, most seroprevalence studies to date have come up with significantly lower rate for adults.

 

In  A lower than expected adult Victorian community attack rate for pandemic (H1N1) 2009 the attack rate among adults in Victoria, Australia was estimated at 10%.

 

And from Clinical Aspects of Pandemic 2009 Influenza A (H1N1) Virus Infection we get this estimation of the attack rate:

 

After the peak of a second wave of infection in Pittsburgh, the seroprevalence of hemagglutination-inhibition antibody suggested that about 21% of all persons and 45% of those between the ages of 10 and 19 years had become infected

 

 

So, a 28% attack rate among adults would seem more than a bit surprising, particularly in Japan, a country renowned for its high standards of hygiene and general phobia of germs.

 

Granted these are health care workers (HCWs), who are more likely to be exposed to the virus, but that brings us to the second point.

 

Namely, that in Japan – where infection control is taken very seriously, and compliance with hand washing and mask wearing among HCWs was undoubtedly very high – those measures apparently proved inadequate barriers to infection.

 

Admittedly, we don’t know how many of these HCWs may have been exposed and infected outside of the workplace, although this study was reportedly conducted early in the transmission stage in Sendai.

 

With a relatively mild influenza, such as novel H1N1 turned out to be, the results were not disastrous to the health care system.

 

But had this been a more virulent influenza strain with a high clinical attack rate, infection of 30% of healthcare workers despite the widespread use of N95s and facemasks would have been of serious concern.

 

Another reason to consider vaccination high among the preventative steps for health care workers.

ICEID: Nasal Polyps And Bird Flu

 

 

# 4719

 

 

 

Earlier today I wrote about the ICEID 2010 conference underway in Atlanta, and gave the link to the slide presentation abstracts.

 

While there are a great many presentations of note, one explores a theory I confess, I’d not heard before;

That nasal polyps and/or allergic rhinitis might make one more susceptible to contracting H5N1.

 

First the abstract, then a little discussion.

 

 

Enhanced Susceptibility of Nasal Polyp Tissues to Avian and Human Influenza Viruses

P. Auewarakul, O. Suptawiwat, P. Tantilipikorn, C. Boonarkart, P. Puthavathana; Mahidol
University, Bangkok, THAILAND

 
Background: Influenza viruses bind and infect respiratory epithelial cells through sialic acid on cell
surface. Differential preference to sialic acid types contributes to host- and tissue-tropism of avian and
seasonal influenza viruses.

 

Although the highly pathogenic avian influenza virus H5N1 can infect and cause severe diseases in humans, it is not efficient in infecting human upper respiratory tract. This is because of the scarcity of its receptor, 2,3-linked sialic acid, in human upper airway. Expression of sialic acid can be influenced by various factors including inflammatory process.

 

Allergic rhinitis and nasal polyp are common inflammatory conditions of nasal mucosa and may affect expression of the sialic acid and susceptibility to influenza infection.

 

Methods: To test this hypothesis, we detected 2,3- and 2,6-linked sialic acid in human nasal polyp and normal nasal mucosal tissues by lectin staining and infected explants of those tissues with avian influenza viruses H5N1 and seasonal influenza viruses.

Results: We show here that mucosal surface of nasal polyp expressed higher level of 2,3- and 2,6-linked sialic acid than normal nasal mucosa. Accordingly, nasal polyp tissues explants were more susceptible to both H5N1 avian influenza viruses and seasonal influenza viruses.

 

Our data suggest a role of nasal allergic conditions in susceptibility to influenza infection, especially by avian influenza viruses, which is generally
inefficient in infecting human upper airway.

 

Conclusions: The increased receptor expression may contribute to increased susceptibility in some individuals.

 

This may contribute to the gradual adaptation of the virus to human population.

 

 

Nasal polyps are small edematous grape-like sacs, filled with inflammatory cells and fluid, than can sometimes develop deep inside the nasal cavity.

 

They can appear singly or in clusters, and may come about as a result of long-standing inflammation, although often the cause is never known.

 

 

I’ll wait while everyone goes `eeewww’.

 

Ok, to continue.

 

In order to infect a host, a virus must attach itself to cells in the host’s body.  Influenza viruses have an affinity for either the alpha 2,3 receptor cell or the alpha 2,6 receptor cell.

 

Avian adapted influenza viruses bind preferentially to Alpha 2,3 receptor cells, which are commonly found in the digestive tract of birds.  This explains why most avian flu viruses are gastrointestinal infections in birds.

 

Human adapted viruses have an affinity for the alpha 2,6 receptor cell, which populate the upper airway and lungs.  This is why influenza is a respiratory virus in humans.

 

There are some crossovers in receptor cells, and humans have some avian-like alpha 2,3 receptor cells, but most are deep in the lungs.  It is harder for avian influenzas to reach those cells, but not impossible.

 

According to this research, however, inflammation processes – such as allergic rhinitis and nasal polyps – generate increased alpha 2,3 and alpha 2,6 receptor cells in the upper airway.

 

Which, theoretically anyway, could increase the odds of human acquisition of the H5N1 virus.

ICEID 2010 Slide Session Abstracts

 

 

# 4716

 

 

 

This is a big news week for infectious disease geeks such as myself, as the International Conference on Emerging Infectious Diseases (ICEID 2010) is underway in Atlanta, Georgia.

 

Last night , the keynotes were delivered (scheduled to appear were):

 

Thomas R. Frieden, Director, CDC

 

Anthony S. Fauci, Director, NIAID  
Emerging Infectious Diseases: A
Perpetual Challenge

 

Keiji Fukuda, Special Advisor, WHO
A Pandemic in the 21st Century:
What Can We Learn

 

And today the full schedule begins, with presentations to continue through Wednesday.

 

The CDC’s EID Journal has published a pdf file of the Silde Sessions Abstracts.  It provides brief summaries of dozens of presentations that will be delivered at this conference over the next three days.

 

Some of these abstracts are intriguing, and I’ll be highlighting a number of them this week. 

 

Along the way, I’ve no doubt we’ll get additional coverage from medical reporters in attendance (something that, alas, I am not).

 

(Click link to open)