UK: Return To The Crypto

Credit CDC PHIL

 

# 7016

 

Like murders, not every disease outbreak ends up being solved, and sometimes success only comes after months of dogged detective work, when the identity, source, and route of an outbreak are at last revealed.

 

Last summer the UK reported a sharp spike in Cryptosporidium (aka `Crypto’) cases during the month of May, which I covered in a pair of blogs (see Tales From The Crypto & More Tales From The Crypto). 

 

At the time, no source of infection was immediately apparent, and so general precautions were offered to the public as the `usual suspects’ were investigated.

 

In June, the HPA released a statement:

 

Update 8 June: Increase in cases of cryptosporidiosis

(EXCERPT)

The Health Protection Agency (HPA) continues to lead a multi-agency investigation to determine whether recent cases of cryptosporidiosis are linked to a common source.

 

<SNIP>

 

So far investigations have not identified a likely source of infection. The Drinking Water Inspectorate has confirmed that there is currently no evidence that public water supplies are implicated.

 

Cryptosporidiosis is caused by an organism called Cryptosporidium, which is found in soil, food, water or surfaces that have been contaminated with infected human or animal droppings. People can become infected by consuming contaminated water or food, by swimming in contaminated water, for example in lakes or rivers, or through contact with infected animals. The most common symptom is diarrhoea, which can range from mild to severe.

(Continue . . .)

 

In January of 2013, in Eurosurveillance: More Tales From The Crypto, we saw a report indicating that in addition to the UK, the Netherlands and Germany also saw unusual spikes in Cryptosporidium infections last summer.

 

Again, no immediate cause, or causes, was identified.  This from the Eurosurveillance report:

 

Because the number of Cryptosporidium-positive samples in the Netherlands, the UK and Germany increased during the same period, common exposures or influencing factors might be expected. However, no single source has been found that could explain the increase of cryptosporidiosis seen in these countries. Foreign travel has been an important risk in the UK and bottled mineral water raised as a hypothesis in the Netherlands.

 

However, plausible factors might include multiple sources, extreme weather conditions, person-to-person transmission and other, still unidentified risk factors. Alternatively, the increase in different countries may have developed independently which could explain the difference in age distribution compared to previous years in the Netherlands but not in the UK and Germany.

 

Yesterday, the HPA announced that – at least in the UK – they’ve identified the likely culprit of last summer’s outbreak, albeit through the use of circumstantial evidence.

 

Investigation into an outbreak of Cryptosporidium infection in spring 2012

19 March 2013

The Health Protection Agency (HPA) can confirm that findings of an investigation into an outbreak of Cryptosporidium infection that affected around 300 people in England and Scotland in May 2012 showed strong evidence of an association with eating pre-cut bagged salad products which are likely to have been labelled as ‘ready-to-eat’. The outbreak was short lived and the numbers of cases returned to expected seasonal levels within a month of the first cases being reported. Most of those affected had a mild to moderate form of illness and there were no deaths associated with the outbreak.

 

The HPA conducted an extensive investigation which involved interviewing people who became unwell about their food history and shopping habits and comparing these with a similar number of people who were not unwell.

 

In the analysis of the exposure to different salad vegetables (irrespective of retailer) a significant statistical association was found between infection and the consumption of pre-cut spinach. When specific retailers were included in the analysis, the strongest association with infection was found to be with consumption of ready to eat pre-cut mixed salad leaves from a major supermarket chain. In this analysis, exposure to pre-cut spinach only reached conventional levels of significance for one retailer - a second major supermarket chain. A link to spinach from a number of other retailers was also suggested but these were not statistically significant. Together these findings suggest that one or more types of salad vegetables could have been contaminated.

 

The Food Standards Agency (FSA), who were part of the outbreak control team led by the HPA, gathered information on the production and distribution of salad vegetables to try to identify the likely source of the outbreak. Investigation of the food chain including practice and procedures throughout each stage of growing, processing, packing and distribution of salad vegetables has not identified a source of contamination. Bagged salad on sale in supermarkets is often sourced from the same suppliers for most leaf types, often with common production lines packing product for several retailers at the same time. This was the situation in this case.

 

Dr Stephen Morton, regional director of the HPA’s Yorkshire and the Humber region and head of the multi-agency Outbreak Control Team, said: “This outbreak was fortunately short lived but it was important to see if we could find the source. Our findings suggest that eating mixed leaf bagged salad was the most likely cause of illness.

 

“It is however often difficult to identify the source of short lived outbreaks of this type as by the time that the outbreak can be investigated, the affected food and much of the microbiological evidence may no longer be available.

(Continue . . . )

 

 

The deduction that mixed leaf bagged salad was behind the UK outbreak is not terribly surprising, as Crypto is often a foodborne illness.

 

According to an EID Journal study published in 2011, there are estimated to be nearly 750,000 Crypto infections in the United States alone each year (see Foodborne Illness Acquired in the United States—Major Pathogens).

 

For most healthy individuals, a Crypto infection is an unpleasant, but not life threatening illness.  The most common symptoms (which generally last 1 to 2 weeks) are:

 

• Watery Diarrhea
• Stomach cramps or pain
• Dehydration
• Nausea
• Vomiting
• Fever
• Weight loss

 

Although rarely fatal in healthy individuals, `Crypto’ can be deadly for the very young, the very old, and those with compromised immune systems.

 

Given its prevalence in the environment, and the number of human infections each year, prevention is key. The CDC maintains an extensive webpage devoted to Prevention & Control of Cryptosporidiosis.

Eurosurveillance: H2H Transmission of NCoV In UK Family Cluster

Photo Credit NIAID

 

# 7007

 

Although we’ve known since the middle of last month (see HPA: UK NCoV Cluster Expands To Three Cases) that human-to-human transmission was strongly suspected in the recent UK family cluster of novel coronavirus cases, today we get considerably more detail via a Rapid Communications that appears in the journal Eurosurveillance.

 

Eurosurveillance, Volume 18, Issue 11, 14 March 2013

Rapid communications

Evidence of person-to-person transmission within a family cluster of novel coronavirus infections, United Kingdom, February 2013

The Health Protection Agency (HPA) UK Novel Coronavirus Investigation team

 

In February 2013, novel coronavirus (nCoV) infection was diagnosed in an adult male in the United Kingdom with severe respiratory illness, who had travelled to Pakistan and Saudi Arabia 10 days before symptom onset.

 

Contact tracing identified two secondary cases among family members without recent travel: one developed severe respiratory illness and died, the other an influenza-like illness. No other severe cases were identified or nCoV detected in respiratory samples among 135 contacts followed for 10 days.

What follows is long and fairly detailed account of the epidemiological investigation into these family members, and their contacts. 

 

Interestingly, this investigation found that the index case, recently returned from Pakistan and Saudi Arabia, was co-infected with influenza A and that both family members who became infected were co-infected with Type 2 parainfluenza virus.

This raises the intriguing possibility that a respiratory virus co-infection might somehow influence the severity, and/or transmissibility of the NCoV virus.

 

At the same time, it serves to remind us that a positive influenza rapid test doesn’t necessarily rule out the possibility of a concurrent NCoV infection.

 

In the index case described in this report, a presumptive diagnosis of Influenza A was made on February 1st, and the NCoV diagnosis was not made until a full week later.

 

 

The third member of this family cluster only developed mild symptoms, and did not require hospitalization.  This being the first clear indication that mild cases may be present, giving rise to the following commentary from this paper:

 

. . .  This first reported case of a milder nCoV illness raises the possibility that the spectrum of clinical disease maybe wider than initially envisaged, and that a significant proportion of cases now or in the future might be milder or even asymptomatic.

 

This highlights the importance of intensive contact tracing and virological and serological follow-up around all confirmed cases of nCoV. The application of recently developed serological assays in one case¬–contact study did not provide evidence of asymptomatic infection, although the contacts investigated were exposed late in the case’s illness, when the viral load might be lower [11].

 

Paired sera are being gathered from contacts in this current investigation to determine whether there may have been more widespread mild or asymptomatic infection.

 

We also learn that – based on a very limited dataset – NCoV appears to have a:

 

`putative incubation period ranging from one to nine days and a serial interval (time between onset of illness in index case and secondary case) of 13 to 14 days.’

This is a fascinating report, well worth reading in its entirety.  I’ve only excerpted a few of the highlights.

 

The authors write towards the end:

 

Public health implications

 

These findings suggest that although person-to-person infection is possible, there is no evidence at present of sustained person-to-person transmission of nCoV in the UK in relation to this cluster. The limited transmissibility is consistent with the data available to date, with only two other reports of small, self-limited clusters of severe disease in the Middle East: one in a healthcare setting and the other in a household setting [5].

 

Furthermore, intensive follow-up of close contacts of two other cases imported to European countries has failed to demonstrate onward transmission [10,11].

<SNIP>

All confirmed nCoV cases detected to date, apart from the two secondary cases in the UK cluster, spent time in the Middle East during the putative incubation period. This, together with our observations of limited secondary transmission, highlights the importance of ongoing vigilance and rapid investigation of cases of severe respiratory illness in residents of and travellers from that area.

 

Further work is required to determine how widely nCoV is circulating globally. In particular serological investigations are needed on the extent of recent infection in various populations, as well as virological investigation of cases of severe undiagnosed respiratory illness in settings both in and beyond the Middle East.

 

While researchers are obviously learning more about NCoV with each passing day (see Nature: Receptor For NCoV Found), it may be some time before they can tell us just how much, or how little, a public health threat this emerging virus actually poses.

 

For now, enhanced surveillance and vigilance in contract tracing is key. 

 

Stay tuned.

HPA: Pandemrix Vaccine Linked To Childhood Narcolepsy In England

 

# 6971

 

Pandemrix was the adjuvanted pandemic H1N1 flu shot developed by GlaxoSmithKline (GSK) and distributed to more than 30 countries beginning in the fall of 2009. This vaccine included a squalene-based component called AS03, used as a adjuvant.

 

Adjuvants are additives that are used to increase the immune response to a vaccine. Their use can allow the `stretching’ of the vaccine supply, as shots can contain a smaller amount of antigens.

 

While they have been used in Europe and in Canada, adjuvanted flu vaccines have not been licensed for use in the United States.

 

Roughly a year after the vaccine was deployed, we began to see reports of an unusual rise in the number of children in Finland (a country where Pandemrix was used) diagnosed with a rare neurological disorder called narcolepsy.

 

For early coverage of this story, you may wish to revisit Finland Suspends Use of Pandemrix Vaccine and EMA To Review Pandemrix Vaccine, both of which I wrote in August of 2010.

 

Despite some conflicting and incomplete data the European Medicines Agency issued a statement in July of 2011 recommending:

 

In persons under 20 years of age Pandemrix to be used only in the absence of seasonal trivalent influenza vaccines, following link to very rare cases of narcolepsy in young people.

 

Finland also convened a Narcolepsy Task Force (see Finland: Task Force Report On Pandemrix-Narcolepsy Link) that confirmed an association – as yet unexplained – between receipt of the vaccine and an increase in narcolepsy in children between the ages of 4 and 19.

 

In September of 2012, the ECDC released a 164 page technical report called Narcolepsy In Association With Pandemic Influenza Vaccination in which the summary found:

 

The case–control study confirms an association between vaccination with Pandemrix® and an increased risk of narcolepsy in children and adolescents (5 to 19 years of age) in Sweden and Finland that originally reported on this issue (signalling countries). No such association was found in adults in these two countries.

 

 

Fast forward to yesterday, and we have a press release from the HPA on a study – just published in the BMJ - that has also found a link between the Pandemrix vaccine and childhood narcolepsy in the UK. 

 

First a link to the study, then some excerpts from the HPA release.

 

 

Risk of narcolepsy in children and young people receiving AS03 adjuvanted pandemic A/H1N1 2009 influenza vaccine: retrospective analysis

BMJ 2013; 346 doi: http://dx.doi.org/10.1136/bmj.f794 (Published 26 February 2013)

Cite this as: BMJ 2013;346:f794

 

Conclusion The increased risk of narcolepsy after vaccination with ASO3 adjuvanted pandemic A/H1N1 2009 vaccine indicates a causal association, consistent with findings from Finland. Because of variable delay in diagnosis, however, the risk might be overestimated by more rapid referral of vaccinated children.

(Continue . . . )

 

While unproven, the authors raise the possibility that the adjuvanted vaccine – rather than directly causing narcolepsy – might have accelerated the process in children who would eventually have gone on to develop the disorder. 

 

A significant dip in the `background rate’ of narcolepsy over the next few years in countries that saw a spike after 2009 ASO3 vaccination would help give this theory more weight.

 

A paucity of safety trials on children, and the public’s memories of the 1976 Swine Flu vaccine debacle, led the HHS to decide not to allow adjuvants in the pandemic flu vaccines deployed in the United States, despite urging by the global community.

 

The HPA has put together the following summary.

 

Pandemic flu vaccination linked to narcolepsy in UK children

27 February 2013

Health Protection Agency (HPA) scientists have found evidence of an association between Pandemrix flu vaccination and narcolepsy in children in England, according to the findings of a study published in the British Medical Journal. These findings are consistent with previous studies from Finland and Sweden which identified a similar association.

 

In collaboration with researchers from Papworth and Addenbrooke’s hospitals in Cambridge, the study looked at 75 children aged between four and 18 who were diagnosed with narcolepsy from January 2008 and who attended sleep centres across England. Eleven of these children had been vaccinated with Pandemrix before their symptoms began, seven of these within six months. This suggests a risk of narcolepsy following vaccination with Pandemrix of around one in every 55,000 doses of the vaccine.

 

The Pandemrix vaccine was recommended for use in children at risk of serious complications from influenza during the pandemic flu outbreak in 2009/10. It was also used occasionally in children during the 2010/11 flu season. Since July 2011 the use of Pandemrix in people under the age of 20 across Europe has been restricted.

 

Although prior to this study, there was no evidence to suggest an association in the UK, on the basis of the findings from Finland the HPA launched an in depth study in February 2011 with narcolepsy experts across England. This investigated whether there was evidence of an association between narcolepsy and Pandemrix as used in the UK.

 

Lead author Professor Liz Miller, a consultant epidemiologist with the HPA, said: "These findings suggest there is an increased risk in children of narcolepsy after Pandemrix vaccination and this is consistent with findings from studies in other European countries. However, this risk may be overestimated by more rapid referral of vaccinated cases. Long term follow up of people exposed to Pandemrix is needed before we can fully establish the extent of the association.

 

“Our findings have implications for the future licensing and use of adjuvanted pandemic vaccines. Further studies to assess the possible risk associated with other vaccines used in the pandemic, including those with and without adjuvants, are also needed to inform the use of such vaccines in the event of a future pandemic.”

 

Study co-author Dr John Shneerson, consultant physician from the Respiratory Support and Sleep Centre at Papworth Hospital in Cambridge, said: “Narcolepsy is thought to be due to a loss of function of a small group of cells in one of the sleep centres in the brain, as a result of an abnormal reaction of the body’s immune system. Pandemrix may have triggered an immune reaction against the sleep centre cells in those children who were genetically predisposed to develop narcolepsy. This study has been important in helping to shed light on the mechanism of how narcolepsy can develop.”

 

Narcolepsy is a chronic neurological disorder caused by the brain's inability to control sleep, particularly REM (dream) sleep. It leads to excessive daytime sleepiness usually accompanied by sudden episodes of muscle weakness triggered by strong emotions such as laughter – this is known as cataplexy. Narcolepsy has a genetic component but this has to be triggered by other factors in order for the condition to appear. 20,000 people in the UK are through to have narcolepsy - drug treatment and lifestyle measures are usually effective in relieving the symptoms.

Ends

 

The exact mechanism behind this Pandemrix-Narcolepsy link remains a medical mystery. Our understanding of this neurological disorder is very limited, as well.  

 

The absolute risk of a child developing narcolepsy from the Pandemrix flu shot appears appears to be about 1 in 55,000. The authors warn that:

 

`Our findings have implications for the future licensing and use of adjuvanted pandemic vaccines’.

 

While a handful of countries had reported increases in post-vaccination narcolepsy, the link between the AS03 adjuvanted vaccine and childhood narcolepsy in the UK has not, until now, been quantified.

 

This study found the increased risk was similar to that previously reported from Finland.

HPA: Not Investigating `4th’ Coronavirus Case

 

Coronavirus – Credit CDC PHIL

# 6963

 

A follow up to a blog on Thursday (Branswell: Possible 4th NCoV Case In UK Cluster), Professor Nick Phin at the HPA has written to ProMed Mail, to clarify that:

 

“ . . . we would like to confirm that the HPA is not currently investigating any 4th possible case associated with the UK cluster of novel coronavirus.”

The entire statement can be viewed at ProMed Mail at the following link:

 

NOVEL CORONAVIRUS - EASTERN MEDITERRANEAN (08): UNITED KINGDOM, 4TH CASE, NOT

HPA Update On UK Family NCoV Cluster

 

Coronavirus – Credit CDC PHIL

# 6951

 

The HPA has published an update on the family cluster of novel coronavirus that infected three people, and has resulted in one death.

 

As this update, and the one from the ECDC earlier today indicate, there are many things we do not know about where this virus comes from, how it is transmitted, and ultimately what risks it may pose.

 

For now, we’ve seen no evidence of sustained or ongoing community transmission of this virus. Contact tracing of roughly two hundred people with possible exposure has – to date – only revealed a dozen confirmed infections.

 

The recent detection of a `mild’ case does raise some concerns that current surveillance techniques might not be sensitive enough to pick up all those infected.

 

Nevertheless, the threat of this novel coronavirus to the general public is still considered low.

 

 

 

Update on family cluster of novel coronavirus infection in the UK

19 February 2013

The Health Protection Agency (HPA) continues its investigations into a family cluster of novel coronavirus infections in the UK. Three members of the same family have all tested positive for novel coronavirus. Two of these had no history of recent travel suggesting that transmission has occurred in the UK.

 

One person has sadly died. This patient had an underlying condition that may have made them more susceptible to respiratory infections. The first patient in this cluster, who had recent travel history to Saudi Arabia and Pakistan, is still receiving treatment. The third case, who had a mild illness, has recovered.

 

Since September 2012, when an earlier case was diagnosed in the UK, there have been a total of 12 confirmed cases of novel coronavirus reported globally, with six deaths. Intensive work has been carried out in the UK to identify contacts of the UK cases. In total the HPA has identified and followed up more than 100 people who had close contact with the cases in this recent family cluster. Besides the identified secondary cases, all tests carried out on contacts to date have been negative for the novel coronavirus infection.

 

Professor John Watson, head of the respiratory diseases department at the HPA, said: "The routes of transmission to humans of the novel coronavirus have not yet been fully determined, but the recent UK experience provides strong evidence of human-to-human transmission in at least some circumstances.

 

“The three recent cases in the UK represent an important opportunity to obtain more information about the characteristics of this infection in humans and risk factors for its acquisition, particularly in the light of the first ever recorded instance of apparently lower severity of illness in one of the cases.

 

“The risk of infection in contacts in most circumstances is still considered to be low and the risk associated with novel coronavirus to the general UK population remains very low. The HPA will continue to work closely with national and international health authorities and will share any further advice with health professionals and the public if and when more information becomes available."

HPA: UK NCoV Cluster Expands To Three Cases

Photo Credit NIAID

# 6942

 

 

The HPA today announced that a second family member of the man, recently returned from the Middle East with a novel coronavirus (NCoV) infection (see WHO Update on Novel Coronavirus (NCoV), has now tested positive. 

 

Unlike the other cases of which we are aware, this person is reportedly only experiencing mild symptoms and is not currently hospitalized. 

 

As NCoV is a recently recognized virus - with only a dozen confirmed cases - our knowledge the range of symptoms and pathogenicity of this virus is still fairly limited. A mild case does add some credence to the idea that there may be cases in the Middle East going unrecognized.

 

Still, epidemiological investigations have followed up on hundred of contacts of known cases, and yet we have only 12 cases identified.  While limited transmission may be occurring, it obviously isn’t currently spreading in an efficient or sustained manner.

 

This from the HPA.

 

Third case of novel coronavirus infection identified in family cluster

15 February 2013

The Health Protection Agency (HPA) can confirm a third case of novel coronavirus infection in a family cluster, following the confirmed diagnosis of two cases announced earlier this week. The patient, who is a UK resident and does not have any recent travel history, is recovering from a mild respiratory illness and is currently well. This latest case brings the total number of confirmed cases globally to 12, of which four have been diagnosed in the UK.

 

Professor John Watson, head of the respiratory diseases department at the HPA, said: "Although this patient had a mild form of respiratory illness, as a precaution the HPA is advising that the patient self-isolate and limit contact with non-household members. Follow up of other household members and contacts of this case is currently underway.

 

“Although this case appears to be due to person-to-person transmission, the risk of infection in contacts in most circumstances is still considered to be low.

 

If novel coronavirus were more infectious, we would have expected to have seen a larger number of cases than we have seen since the first case was reported three months ago. However, this new development does justify the measures that were immediately put into place to prevent any further spread of infection and to identify and follow up contacts of known cases.

 

“We would like to emphasise that the risk associated with novel coronavirus to the general UK population remains very low. The HPA will continue to work closely with national and international health authorities and will share any further advice with health professionals and the public if and when more information becomes available."

HPA Confirms Locally Acquired Coronavirus Infection In UK

Photo Credit NIAID

 

# 6932

 

The big news of the morning comes from the UK where the HPA has announced that a family contract of the man who recently returned from the Middle East with the novel coronavirus has contracted the virus.

 

While there has been some evidence to suggest limited human-to-human transmission of this novel virus in the past, this is the first well-documented case of apparent secondary transmission of the virus.

 

Overall, however, given the number of patients and number of people exposed to them, this virus does not yet show signs of being easily transmissible.

 

 

 

Further UK case of novel coronavirus

13 February 2013

The Health Protection Agency (HPA) can confirm a further case of novel coronavirus infection in a family member of the case announced on Monday 11 February. The patient, who is a UK resident, does not have any recent travel history and is currently receiving intensive care treatment at The Queen Elizabeth Hospital, Birmingham. It is understood that this patient has an existing medical condition that may make them more susceptible to respiratory infections. This latest case brings the total number of confirmed cases globally to 11, of which three have been diagnosed in the UK.

 

Professor John Watson, head of the respiratory diseases department at the HPA, said: "Confirmed novel coronavirus infection in a person without travel history to the Middle East suggests that person-to-person transmission has occurred, and that it occurred in the UK. This case is a family member who was in close personal contact with the earlier case and who may have been at greater risk of acquiring an infection because of their underlying health condition.

 

“To date, evidence of person-to-person transmission has been limited. Although this case provides strong evidence for person to person transmission, the risk of infection in most circumstances is still considered to be very low. If novel coronavirus were more infectious, we would have expected to have seen a larger number of cases than we have seen since the first case was reported three months ago. However, this new development does justify, the measures that were immediately put into place to prevent any further spread of infection and to identify and follow up contacts of known cases.

 

“We will continue to provide advice and support to healthcare workers looking after the patients and to contacts of both cases.

 

"In light of this latest case we would like to emphasise that the risk associated with novel coronavirus to the general UK population remains very low. The HPA will continue to work closely with national and international health authorities and will share any further advice with health professionals and the public if and when more information becomes available."

UK: Whooping Cough Numbers Decline After Record Year

 

Credit CDC

# 6902

 

Reports of Pertussis or `whooping cough’ have been on the ascendant around the globe the past few years, including in the United States, Australia, and the UK.

 

Over the past few months I’ve blogged on the UK’s record setting year for Whooping cough several times, including:

 

HPA: Whooping Cough Cases Remain High

UK: Three Whooping Cough Deaths In October

The UK’s Whooping Cough Outbreak

 

Today, a little bit of encouraging news, as the number of new Pertussis cases reported by the HPA have declined for the second month in a row. It is too early, however, to read much into what this means for the rest of 2013.

 

Cases of whooping cough decline after record numbers in 2012

1 February 2013

There were 9,741* confirmed cases of whooping cough reported in England and Wales in 2012, according to figures published today by the Health Protection Agency (HPA). The total figure for 2012 is almost 10 times higher than the number of cases reported in 2011 (1,119) and in 2008 (902) – the last peak year before this current outbreak.

 

The December figures show a decrease for the second month running in cases of whooping cough with 832 confirmed cases reported compared with 1,168 cases in November 2012. One further death in an infant with laboratory confirmed whooping cough was reported in December bringing the 2012 total number of deaths in babies under three months to 14.

 

The highest number of cases were reported in those aged 15 and over, with a total of 8,059 cases in 2012, compared to 740 cases in 2011 and 493 cases in 2008.

 

Dr. Mary Ramsay, head of immunisation at the HPA, said: “The December figures show another welcome decrease in the overall number of whooping cough cases since the peak in October. However, it is very important to note that we usually see a reduction in cases of whooping cough at this time of year so this decrease is in line with normal seasonal patterns.

(Continue . . .)

 

Before we pop the Champaign corks, it is important to note that the total number of cases reported during the month of December (n=832) is nearly double the total reported in all of 2010 (n=422).

Still, any decline is welcome news.

 

The reasons behind the spike in Pertussis cases are complex, and not completely understood, but some factors may include:

• lower vaccination uptakes
• the move away from whole cell pertussis vaccines to safer – but less broadly protective  - acellular vaccines in the 1990s
• evolutionary changes in the Bordetella pertussis bacteria.

 

Recent evidence published in the NEJM suggests that protection from the newer acellular pertussis vaccine – introduced in the early 1990s – may wane sooner than previously suspected. 

 

Waning Protection after Fifth Dose of Acellular Pertussis Vaccine in Children

Nicola P. Klein, M.D., Ph.D., Joan Bartlett, M.P.H., M.P.P., Ali Rowhani-Rahbar, M.D., M.P.H., Ph.D., Bruce Fireman, M.A., and Roger Baxter, M.D.

N Engl J Med 2012; 367:1012-1019 September 13, 2012DOI: 10.1056/NEJMoa1200850

 

In November of last year, in JAMA: Waning Pertussis Vaccine Effectiveness Over Time, we saw another study that found that the protective effect of the Pertussis vaccine begins to wane after the fifth dose (normally given at age 5) is received, leaving 7 to 10 year olds at greater risk of infection.

 

For more information, the CDC maintains an extensive Whooping Cough website, including audio files designed to help you identify the often distinctive `whooping’ sound made by those infected.

 

Pertussis (Whooping Cough)

 

And from the Advisory Committee on Immunization Practices (ACIP) this week we get recommendations that adults aged 65 and older and pregnant women receive the Tdap vaccine.

 

Advisory Committee on Immunization Practices (ACIP) Recommended Immunization Schedule for Adults Aged 19 Years and Older — United States, 2013

Supplements

February 1, 2013 / 62(01);9-19

(EXCERPT)

For tetanus, diphtheria, and acellular pertussis (Tdap) vaccine, recommendations have been expanded to include routine vaccination of adults aged 65 years and older and for pregnant women to receive Tdap vaccine with each pregnancy. The ideal timing of Tdap vaccination during pregnancy is during 27–36 weeks' gestation. This recommendation was made to increase the likelihood of optimal protection for the pregnant woman and her infant during the first few months of the infant's life, when the child is too young for vaccination but at highest risk for severe illness and death from pertussis

HPA: Unusual Number Of PVL Pneumonia Cases In the UK

Credit CDC

 

# 6892

 

In an article called Warning over killer pneumonia linked to flu, Rebecca Smith, Medical Editor for The Telegraph writes today that a rare type of bacterial pneumonia – one that usually only accounts for 30 to 40 cases each year in the UK - has been identified in 18 cases of community acquired pneumonia between December 6th and January 7th.

 

The culprit is a strain of Staphylococcus aureus that carries a gene for PVL (Panton-Valentine leukocidin) – which is a potent cytotoxin that can destroy human neutrophils (white blood cells), spark severe infections, and cause necrotizing pneumonia.

 

PVL producing genes have been detected in at least 14 different strains of S. aureus (cite BMJ), but are found in less than 2% of all S. aureus bacteria. It is most commonly associated with aggressive skin and soft tissue infections (SSTIs), but it is also the cause of a small number of severe (usually community-acquired) pneumonia cases each year. 

 

S. aureus is a very common bacteria that is carried asymptomatically by as much as 30% of the population  – including some strains with the PVL gene – as part of the normal bacterial flora of their skin and mucus membranes (see Coffee, Tea, or MRSA?).

 

The HPA website describes PVL (updated July 2012) this way:

 

PVL-associated Staphylococcus aureus

Panton-Valentine Leukocidin (PVL) is a toxic substance produced by some strains of Staphylococcus aureus which is associated with an increased ability to cause disease.

 

Although several other countries have encountered widespread problems with PVL-related disease, infections caused by PVL remain uncommon in the UK and, to date, most have been caused by bacteria which are sensitive to a range of antibiotics.

 

PVL has been seen in the UK since the 1950s and 60s but cases continue to be seen here only in small numbers. There is currently no UK-based evidence to suggest that children are more vulnerable than other groups to PVL-related infections or that these infections are acquired or spread through playgrounds.

 

The risk to the UK general public of becoming infected with PVL Staphylococcus aureus is small but the Agency is actively working alongside healthcare colleagues to raise awareness of this infection, as well as ensuring appropriate research continues to monitor trends in infection.

 

PVL genes can be found in  both methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) strains.  According to today’s article in The Telegraph.

 

The 18 cases have all needed intensive care and several required sophisticated life-support known as ECMO, where oxygen is pumped into the blood outside the body because the lungs are overwhelmed with infection.

 

The patients ranged in age from four to 63 years with a median age of 41 and most have flu-like symptoms before developing pneumonia. In five cases the bug had spread between family members.

 

The Telegraph article refers to an HPA bulletin on these cases, but I’ve been unable to locate it as of this writing.  I’ll update this post with a link when it becomes available.

 

From the Annals of Intensive Care in 2011, we get some interesting research on PVL pneumonia, that looked at 32 case reports, with an overall mortality rate of 41%. 

 

They describe the infection:

 

Community-acquired necrotizing pneumonia due to S. aureus-secreting PLV toxin is a highly lethal infection, affecting a young and healthy population group [5]. The hallmarks are an influenza-like prodrome, leukopenia, rapid progression to septic shock, and respiratory distress, with multilobar necrosis and haemoptysis [5,6,14].

 

The Open Access article is available at:

Community-acquired necrotizing pneumonia due to methicillin-sensitive Staphylococcus aureus secreting Panton-Valentine leukocidin: a review of case reports

Lukas Kreienbuehl^1*, Emmanuel Charbonney² and Philippe Eggimann

 

In examining the records of 32 patients, they concluded:

 

Conclusions

Necrotizing pneumonia due to PVL-secreting S. aureus mandates prompt recognition and specific treatment to prevent premature death in immunocompetent patients.

 

Early suspicion should be triggered by the presence of influenza-like prodrome, leucopenia, rapid progression to septic shock, respiratory distress with multilobar necrosis, and hemoptysis.

 

For PVL-secreting MSSA-necrotizing pneumonia, influenza-like prodrome may be associated with fatal outcome, whereas previous SSTI may reduce mortality. Further studies based on a larger patient number are necessary to confirm this finding.

 

Today’s story from the UK mention 5 cases of family transmission, which is somewhat reminiscent of a story we followed last spring at the end of what was an otherwise lackluster 2011-12 flu season.

 

Our attention was briefly directed towards three members of a family (out of five who fell ill) that died from a respiratory infection in Calvert County, Maryland (see Calvert County: Update On Fatal Cluster Of Respiratory Illness).

 

While these deaths made national headlines and spurred considerable speculation as to the viral cause, in the end we learned that it was seasonal H3N2 influenza, exacerbated by a MRSA (or necrotizing) pneumonia co-infection.

 

According to The Telegraph article, the HPA is not worried this will to turn into an epidemic, but since early diagnosis is crucial, they are urging that, “Healthcare personnel should remain vigilant for such cases, especially during the influenza/ respiratory virus season.”

 

The HPA provides the following HCP guidance for the treatment of PVL pneumonia on their website.

 

Steering Group on Healthcare Associated Infection; Guidance on the diagnosis and management of PVL-associated Staphylococcus aureus infections (PVL-SA) in England, 2nd Edition. 2008

 

Management of PVL-Staphylococcus aureus, Health Protection Agency, Local and Regional Services; Recommendations for Practice 2010

 

Staphylococcus aureus, Health Protection Agency (HPA)

UK: HPA Reports Decline In Flu Activity

Current Season in RED – Credit HPA

 

# 6877

 

 

While the flu season continues in full force across much of North America, in the UK the HPA this week is reporting significant declines in influenza and influenza-like activity.

 

Unlike the H3N2 dominated flu season we’ve seen in the United States and Canada, influenza B appears to be leading the viral charge in the UK.

 

It is possible – as we saw in Hong Kong last year – to see more than one peak in a flu season. With several more `flu prone months’ ahead, one can’t necessarily assume the flu season is over for this year in the UK.

 

 

Weekly update on seasonal infections: 24 January 2013

24 January 2013

Latest figures from the Health Protection Agency (HPA) up to 24 January 2013 show that flu activity has decreased compared to the previous week based on a number of indicators, including GP consultation rates in England and the proportion of calls to NHS direct.

 

The number of laboratory confirmed cases of norovirus have also fallen again over the last week with 233 cases being reported during the first week of January and 168 in week two.

 

The latest figures show that GP consultation rates in England have decreased from 24.8 per 100,000 last week to 13.6 this week. Rates have also decreased in Northern Ireland (53.7 down from 72.4), Scotland (33.8 down from 52.22) and Wales (11.2 down from 26.1).

 

Calls received by NHS Direct for cold and flu remained stable below the threshold of 1.6 per cent and the calls for fever in five to 14 year olds increased slightly but remained below the flu threshold of 11.7 per cent.

 

There have been 4,720 confirmed cases of norovirus so far this season (from the beginning of July 2012 to January 13, 2013). This is 49 per cent higher than the number of cases reported to the same point last year when there were 3,168.

 

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For the latest national flu report refer to the  HPA National Influenza Report - week 4 (2013) (PDF, 629 KB)  document.

For the latest national flu graphs see the HPA Weekly National Influenza Graphs (PDF, 714 KB) document.

 

Laboratory confirmed influenza in the UK this season has been primarily Influenza B, followed by A/H3N2.

The most recent virological analysis of flu activity from the HPA indicates:

 

90 (12.7%) of the 709 respiratory specimens reported to DataMart (England) tested positive for influenza in week 3 (48 B, 16 A(H3), 20 A subtype not known and 6 A(H1N1)pdm09).

The proportion of samples positive in DataMart (England) increased for rhinovirus and remained stable for RSV, hMPV, adenovirus and parainfluenza.

7 influenza positive detections were recorded through the two English GP-based sentinel schemes in week 3 (5 B, 1 A(H3) and 1 A(H1N1)pdm09), giving a positivity of 44%

 

The UK’s norovirus season continues to run about 50% above last year, due primarily to the introduction of a new GII.4 variant, dubbed Sydney 2012 (see  UNSW: Sydney 2012 Norovirus Rising).

HPA: Flu Activity In The UK

 

 

# 6820

 

While the United States and Canada have reported an early start to the flu season this year, influenza has yet to take off in Hong Kong (see latest Flu Express (Week 52, 2012), and in the UK and parts of Europe the flu season is just now starting to pick up. 

 

 

The RED LINE indicates this year’s activity, compared to previous years.  The Blue Line indicates the unusually severe 1999-2000 flu season.

 

 

This latest flu updates from the HPA.

 

HPA National Influenza Report

Report published 3 January 2013

Figures (including all those found in this report) displaying data from these schemes are available to download as a pdf file:

HPA Weekly National Influenza Graphs (PDF, 713 KB)

PDF versions of previous reports are available on the archive page.

This week's report is available as a pdf:

HPA National Influenza Report - week 1 (2013) (PDF, 665 KB)

A summary report will be published weekly. For further information on the surveillance schemes mentioned in this report, please see the Sources of UK Flu Data page.

Increases continue to be seen for several indicators of influenza activity. A letter has been issued to the NHS that GPs may now prescribe antiviral medicines for the prophylaxis and treatment of influenza in accordance with NICE guidance.

 

Flu activity update: 3 January 2013

3 January 2013

Latest figures from the Health Protection Agency (HPA) up to 30 December 2012 show that flu activity continues to increase based on a number of indicators, including GP consultation rates in England and the proportion of calls to NHS Direct.

 

The latest figures show that GP consultation rates have increased slightly from 27.4 per 100,000 in week 51 to 32.7 per 100,000 in week 52 ending on 30 December. Meanwhile, 2.1% of the calls received by NHS Direct concerned influenza compared to 1.6% in week 51.

 

Professor John Watson, head of the respiratory disease department at the HPA said:

 

“Over the Christmas period we have seen a slight rise in flu activity across several of our indicators in line with the trend we expect to see at this time of year.

 

“However, the latest data should be interpreted with caution due to GP practices being closed on the bank holidays which may have impacted on GP consultation rates.

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Elsewhere in Europe, the most recent EuroFlu report states:

 

Influenza activity is increasing slowly in the WHO European Region

Summary, week 51/2012

Influenza activity is slowly increasing with more countries in different parts of the Region reporting sporadic co-circulation of influenza A(H1N1)pdm09, A(H3N2) and type B viruses. This week the reporting of influenza surveillance data is incomplete due to the Christmas holidays. This is reflected in the lower number of testing performed. However the percentage of influenza-positive samples from both sentinel and non-sentinel sources are similar to last week. The number of reported hospitalizations due to severe acute respiratory infection (SARI) remains similar to that seen in the previous several weeks: 1 influenza detection was reported (influenza B).

HPA Norovirus Update

Norovirus – Credit HPA

 

# 6817

 

The UK’s HPA has released a new update on their busy norovirus season, which has prompted headlines in British papers announcing more than One Million Cases this year.

 

That number is an extrapolation, based on the assumption that there are 288 uncounted cases for every case officially diagnosed.

 

So take it as an estimate, not a precise count.  Still, reported cases of norovirus are well ahead of last year’s numbers across the UK.

 

 

HPA update on seasonal norovirus activity: 2 January 2013

2 January 2013

Latest figures from the Health Protection Agency (HPA) show there have been 3,877 laboratory confirmed cases of norovirus this season (from week 27 to week 51 2012). The latest figures are 72 per cent higher than the number of cases reported at this point last year, when there were 2,255 cases.

 

During the Christmas period there is typically a drop in the number of laboratory reports. In previous norovirus seasons the general trend is that cases increase in the New Year and we expect to see cases rise again over the next few weeks.

 

During the two weeks up to 30 December there were 29 hospital outbreaks reported, compared to 70 in the previous fortnight, bringing the total of outbreaks for the season to 590.

 

Cases of norovirus have risen earlier than expected this winter season and this is a trend that has been seen across Europe and other parts of the world. It has not yet been determined why this has been the case and activity varies significantly from year to year.

 

John Harris, an expert in norovirus from the HPA said: “As we have seen in previous years there has been a dip in the number of confirmed laboratory reports owing to the Christmas and New Year period. However, in line with other norovirus seasons we will expect to see an increase in the number of laboratory reports in the next few weeks.

 

“Norovirus is very contagious, and anyone who has had it knows it is very unpleasant. If you think you may have the illness then it is important to maintain good hand hygiene to help prevent it spreading. We also advise that people stay away from hospitals, schools and care homes as these environments are particularly prone to outbreaks.”

 

Norovirus can be transmitted by contact with contaminated surfaces or objects, by contact with an infected person, or by the consumption of contaminated food or water. Symptoms of norovirus include a sudden onset of vomiting and/or diarrhoea. Some people may have a temperature, headache and stomach cramps. The illness usually resolves in one or two days and there are no long-term effects.

Ends

Notes to editors

1. Indications from Europe and Japan are that norovirus activity also started to increase early. In Australia the norovirus season also peaks during the winter but this season it has gone on longer than usual and they are seeing cases into their summer. The HPA is following up with colleagues internationally.
2. The number of laboratory confirmed cases represents just a fraction of the actual amount of norovirus activity as it is estimated that for each confirmed case, there are a further 288 unreported cases, as the vast majority of those affected do not seek healthcare services in response to their illness. Data from The Infectious Intestinal Diseases II (IID II) report can be found at the Food Standards Agency website [external link].

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For more on noroviruses, you may wish to revisit the following blogs.

 

Vomiting Larry And His Aerosolized Norovirus

An Unwanted Lagniappe From The Kitchen

UK: Norovirus Season Starts Early

HPA: Whooping Cough Cases Remain High

Credit CDC

# 5798

 

Updating a story from late in November (see UK: Three Whooping Cough Deaths In October), while the number of new UK Pertussis cases reported in November dropped over the previous month, they still remain well above average.

 

The HPA released the following update this morning.

 

Whooping cough cases remain high

21 December 2012

Figures published by the Health Protection Agency (HPA) today show that cases of whooping cough have continued at high levels during November with 1,080 confirmed cases reported for England and Wales, bringing the total number of cases so far this year to 8,819*. No deaths were reported in November.

 

The total of 1,080 cases reported during November represents a decrease from October when 1,631 cases were reported for England and Wales, which is the first time we’ve seen a decrease in monthly numbers since the current outbreak began in the middle of 2011. However, a decrease in cases is usually seen at this time of year so this does not necessarily represent the end of this severe outbreak.

 

At the end of September, the Department of Health announced that pregnant women would be offered whooping cough vaccination to protect their newborn babies, who do not usually start their vaccinations against whooping cough until they are two months of age. The aim of the vaccination programme is to help to boost the short term immunity passed on by women to their babies while they are still in the womb.

 

It is too soon for this vaccination campaign to have had an impact on the case numbers we are seeing, however, the Department of Health recently reported an uptake of around 40 per cent in pregnant women.

 

Dr Gayatri Amirthalingam, consultant epidemiologist for immunisation at the HPA, said: “The November figures show a welcome decrease of whooping cough cases since October. However, it is very important to note that we usually see a reduction in cases of whooping cough at this time of year so this decrease is in line with normal seasonal patterns.

 

“The recent announcement that at least 40 per cent of pregnant women received the whooping cough vaccine in the first month of the programme is very encouraging. We would like to remind pregnant women how serious this infection can be in young babies and how it can in some cases cause death. Vaccination between 28 and 38 weeks of pregnancy should offer babies the best protection against whooping cough before they receive their own vaccines.

 

“As well as this, parents should ensure their children are vaccinated against whooping cough on time, even babies of women who’ve had the vaccine in pregnancy – this is to continue their baby’s protection through childhood."

 

Whooping cough, also known as pertussis, affects all ages. Young infants are at highest risk of severe complications and death from whooping cough as babies do not complete vaccination until they are around four months old. In older children and adults whooping cough can be an unpleasant illness but it does not usually lead to serious complications. Whooping cough is a highly infectious bacterial disease which spreads when a person with the infection coughs and sheds the bacteria which is then inhaled by another person.

 

Dr Amirthalingam continues, “Parents should also be alert to the signs and symptoms of whooping cough – which include severe coughing fits accompanied by the characteristic “whoop” sound in young children but as a prolonged cough in older children or adults.”

(Continue . . . )

 

 

 

The reasons behind the spike in Pertussis cases (not only in the UK, but in the U.S., Australia, and elsewhere) are complex, and not completely understood, but some factors may include:

 

• lower vaccination uptakes
• the move away from whole cell pertussis vaccines to safer – but less broadly protective  - acellular vaccines in the 1990s
• evolutionary changes in the Bordetella pertussis bacteria.

 

Recent evidence published in the NEJM suggests that protection from the newer acellular pertussis vaccine – introduced in the early 1990s – may wane sooner than previously suspected. 

 

Waning Protection after Fifth Dose of Acellular Pertussis Vaccine in Children

Nicola P. Klein, M.D., Ph.D., Joan Bartlett, M.P.H., M.P.P., Ali Rowhani-Rahbar, M.D., M.P.H., Ph.D., Bruce Fireman, M.A., and Roger Baxter, M.D.

N Engl J Med 2012; 367:1012-1019 September 13, 2012DOI: 10.1056/NEJMoa1200850

 

 

While not 100% perfect, the Pertussis vaccine remains the best way to prevent Whooping Cough.

 

As noted above, the rise in whooping cough isn’t just a problem in the UK.  The graphic below shows that – except for California – every state in the union has reported an increase in Pertussis cases this year over 2011 (through week 46). 

 

For more on the prevention of Whooping Cough, and the role of the Tdap vaccine, visit:

 

http://www.cdc.gov/pertussis/

 

UK: Three Whooping Cough Deaths In October

 

Credit CDC

 

# 6749

 

Whooping cough has been in the news (and in this blog) a lot this week (see Safety Of Tdap Vaccine In Older Patients and Waning Pertussis Vaccine Effectiveness Over Time), and with an announcement overnight from the HPA, today I go for the hat trick.

 

Last month (see The UK’s Whooping Cough Outbreak) we looked at the rising pertussis numbers in the UK, and the announcement that that pregnant women would be offered the Pertussis vaccine in order to protect their newborns, who cannot be vaccinated until they are 2 – 4 months of age.

 

The latest announcement from the HPA indicates that during the month of October more than 1,600 additional cases of Whooping cough were reported in England and Wales, resulting in 3 infant deaths.  This brings the death toll in 2012 to 13.

 

As you can see by the chart below, Pertussis in 2012 is running roughly 10 times the rate seen in recent years.

 

 

The reasons behind this latest spike in Pertussis cases are complex, and not completely understood, but some factors may include:

• lower vaccination uptakes
• the move away from whole cell pertussis vaccines to safer – but less broadly protective  - acellular vaccines in the 1990s
• evolutionary changes in the Bordetella pertussis bacteria.

 

Here are some excerpts from the HPA’s press release:

 

Whooping cough cases continue to increase

30 November 2012

Figures published by the Health Protection Agency (HPA) today reveal 1,614 cases of whooping cough were reported in England and Wales in October 2012, bringing the total number of cases so far this year to 7,728*.

 

The total number of cases so far in 2012 (up to end of October) is nearly ten times higher than for the same period in 2008, the last ‘peak’ year before this current outbreak, when 797 cases were reported. There have been three deaths in infants with laboratory confirmed whooping cough reported in October bringing the total number of deaths in this age group so far this year to 13.

 

At the end of September, the Department of Health announced that pregnant women would be offered whooping cough vaccination to protect their newborn babies, who do not usually start their vaccinations against whooping cough until they are two months of age. The aim of the vaccination programme is to help to boost the short term immunity passed on by women to their babies while they are still in the womb.

 

Dr Gayatri Amirthalingam, consultant epidemiologist for immunisation at the HPA, said: “The October figures show a continuing rise in the overall number of whooping cough cases. While there has been a decline in the number of infant cases it’s important to emphasise that it’s too early to see any impact from the pregnancy vaccination programme. Working with the Department of Health we are continuing to carefully monitor whooping cough activity to evaluate the success of the programme.

 

“We strongly recommend all pregnant women take up the offer of vaccination. Parents should also ensure their children are vaccinated against whooping cough on time, even babies of women who’ve had the vaccine in pregnancy – this is to continue their baby’s protection through childhood. Parents should also be alert to the signs and symptoms of whooping cough – which include severe coughing fits accompanied by the characteristic “whoop” sound in young children but as a prolonged cough in older children or adults. It is also advisable to keep babies away from older siblings or adults who have the infection.”

 

Whooping cough, also known as pertussis, affects all ages. Young infants are at highest risk of severe complications and death from whooping cough as babies do not complete vaccination until they are around four months old. In older children and adults whooping cough can be an unpleasant illness but it does not usually lead to serious complications. Whooping cough is a highly infectious bacterial disease which spreads when a person with the infection coughs and sheds the bacteria which is then inhaled by another person.

(Continue . . . )

 

 

For more information, the CDC maintains an extensive Whooping Cough website, including audio files designed to help you identify the often distinctive `whooping’ sound made by those infected.

 

Pertussis (Whooping Cough)

Pertussis, also known as whooping cough, is a highly contagious respiratory disease. It is caused by the bacterium Bordetella pertussis.

Pertussis is known for uncontrollable, violent coughing which often makes it hard to breathe. After fits of many coughs, someone with pertussis often needs to take deep breathes which result in a "whooping" sound. Pertussis most commonly affects infants and young children and can be fatal, especially in babies less than 1 year of age.

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