How Dangerous is Bird Flu (H5N1) to Global Public Health? Part 1 (Feb 16, 2011 - Oct 16, 2011)

[AlaskaDenise]

Re: How Dangerous is Bird Flu, H5N1 to Global Public Health?

Re: How Dangerous is Bird Flu, H5N1 to Global Public Health?

........The situation is a remind of the almost complete failure in controlling if not eradicating the disease in animals since the A(H5N1) virus appearance in 2003.

Despite an huge amount of papers, meetings, donors' funds pledges - the disease persists and humans serve as 'sentinel' in most cases for detecting poultry outbreaks.

The H5N1 'case' is one of the increasing number of unresolved crisis around the world and despite the potential threat to human health globally, most of the developed nations resist to do enough to help reduce the impact on local population livelihood and contribute to maintain a source of infection.

Since the influenza virus behaviour remains largely unpredictable, any possible effort should be addressed in the field of animal welfare and in novel therapeutical and immunization strategies.

I think you make an important point that the world is not effectively dealing with the increasing threat of zoonotic diseases.

I'm not sure we can vaccinate our way out of this one. There will always be a considerable population of poor people who cannot afford protention and given the increasing food shortages, there will be more pressure to not cull flocks of threatened birds.

When I consider behavior/cultural changes in animal/food production I looked for other examples and couldn't identify any. Are there any examples of global changes in animal/food production practices to eliminate a disease that were effective? This may come down to one of the many cultural changes that happen only as a result of disaster. However, science can identify needed changes.

.

 

[Giuseppe]

Re: How Dangerous is Bird Flu, H5N1 to Global Public Health?

Re: How Dangerous is Bird Flu, H5N1 to Global Public Health?

Highly Pathogenic Avian Influenza Virus (H5N1) Outbreak in Captive Wild Birds and Cats, Cambodia (Emerg Infect Dis.)


DOI: 10.3201/eid1503.081410
Suggested citation for this article: Desvaux S, Marx N, Ong S, Gaidet N, Hunt M, Manuguerra J-C, et al. Highly pathogenic avian influenza virus (H5N1) outbreak in captive wild birds and cats, Cambodia. Emerg Infect Dis. 2009 Mar; [Epub ahead of print]

[Full PDF Document at LINK. EDITED.]

Highly Pathogenic Avian Influenza Virus (H5N1) Outbreak in Captive Wild Birds and Cats, Cambodia

St?phanie Desvaux, Nick Marx, Sivuth Ong, Nicolas Gaidet, Matt Hunt, Jean-Claude Manuguerra, San Sorn, Malik Peiris, Sylvie Van der Werf, and Jean-Marc Reynes

Author affiliations: Centre de Cooperation Internationale en Recherche Agronomique pour le D?veloppement, Montpellier, France (S. Desvaux, N. Gaidet); WildAid, Phnom Penh, Cambodia (N. Marx, M. Hunt); Institut Pasteur du Cambodge, Phnom Penh (S. Ong, J.-M. Reynes); Institut Pasteur, Paris, France (J.-C. Manuguerra, S. Van der Werf); National Animal Health and Production Investigation Center, Phnom Penh (S. Sorn); and University of Hong Kong and Queen Marie Hospital, Pokfulam, Hong Kong Special Administrative Region, People?s Republic of China (M. Peiris)


From December 2003 through January 2004, the Phnom Tamao Wildlife Rescue Centre, Cambodia, was affected by the highly pathogenic influenza virus (H5N1). Birds from 26 species died. Influenza virus subtype H5N1 was detected in 6 of 7 species tested. Cats from 5 of 7 species were probably infected; none died.


(...)
Conclusions
The sources of introduction of HPAIV (H5N1) within the PTWRC were probably multiple: virus-infected chicken bought to feed the carnivorous species, infected live chickens brought to restaurants near S2 (i.e., the first place where deaths were detected), and contact between infected wild and captive birds. The introduction through infected chickens is supported by the absence of an outbreak at the PTWRC after the feeding of chickens to carnivorous species was discontinued; however, deaths in domestic poultry continued in the area. In addition, almost all carnivorous bird species in S2 died (93% of Falconiformes and 92% of Strigiformes) as did most species usually fed chicken meat in captivity (herons, storks, crows, great hornbill, pelican). Diet was also the origin of the outbreak among tigers and leopards in Thailand (6,7). The dispersion of the disease between PTWRD sections was probably due to poor biosecurity measures.

The clinical outcome of wild birds with suspected HPAIV (H5N1) infection at PTWRC ranged from severe illness and death to complete absence of clinical signs, as described (8). Several species from the orders Ciconiiformes, Galliformes, Passeriformes, Gruiformes, Coraciiformes, and Pelecaniformes were affected during the outbreak. This observation is consistent with data published earlier, except for Coraciiformes represented by 1 bird in our study (9). Only the carnivorous species (Corvus macrorynchos) among the 5 species of Passeriformes in the aviaries showed clinical signs and later was confirmed by RT-PCR to be positive for HPAIV (H5N1).

This outbreak confirms that Falconiformes and Strigiformes are sensitive to HPAIV (H5N1) infection and disease (10?12) and shows that numerous species of these orders can be affected by HPAIV (H5N1) (Table 1).

Psittaciformes and Columbiformes were not visibly affected by the outbreak although they were kept in large numbers in S2, where large numbers of deaths occurred. As non?water-bird species, they do not belong to groups in which avian influenza is commonly reported (13).

Anseriformes, represented in PTWRC by only 4 birds (Anas poecilorhyncha), did not show any clinical signs. Heterogeneity in the susceptibility of wild ducks to HPAIV (H5N1), including asymptomatic infection, has been demonstrated (14); this species also belongs to the group of wild ducks found asymptomatically infected with HPAIV (H5N1) in the People?s Republic of China during the winter of 2005 (15).

The serologic evidence of influenza virus (H5N1) infection in 4 species of wild cats is in agreement with previous infection in Thailand (6,7). The report of illness in the Asiatic golden cat (Catopuma temminckii) and the clouded leopard (Neofelis nebulosa) broadens the host range of the virus among mammals.

This report confirms the great variability of wild bird and mammal responses to HPAIV (H5N1) infection. It also confirms the broadening range of susceptible species that may be specific to this clade 1 virus.

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[Giuseppe]

Re: How Dangerous is Bird Flu, H5N1 to Global Public Health?

Re: How Dangerous is Bird Flu, H5N1 to Global Public Health?

(...)

(4) [PANDEMIC PREPAREDNESS, RESEARCH, CAMBODIA, CIDRAP] Cambodian study hints at subclinical H5N1 cases
Jan 25, 2008 (CIDRAP News) ?

A recent study in Cambodia suggests that some human cases of infection with the H5N1 avian influenza virus escape detection because symptoms are mild or absent, according to a report from an international avian flu conference this week in Bangkok.
​

The meeting drew about 500 experts from 40 countries to discuss research and ideas on a wide range of topics. Some other topics discussed included the idea of stockpiling vaccine adjuvants to prepare for a pandemic, the use of engineered human antibodies as a defense against the H5N1 virus, and the high H5N1 case-fatality rate in Indonesia.

Cambodian study
The Cambodian researchers tested 674 people in two villages who were exposed to the virus and found that seven of them, all between the ages of 4 and 18, had antibodies signaling previous infection, according to a Jan 24 Bloomberg News report.
​

The finding contrasts with previous serologic studies of people in areas affected by H5N1 outbreaks.
A review published Jan 16 in the New England Journal of Medicine (NEJM) said the few serologic studies since 2003 of people with potential exposure to H5N1 suggest that asymptomatic or mild cases are rare.
The studies involved people living with backyard poultry, workers in live-bird markets, and healthcare workers.
More cases of mild disease might suggest that the virus is improving its ability to spread among humans, while becoming less virulent.
Based on the current global count of 353 cases with 221 deaths, the case-fatality rate is almost 63%.
The Cambodian researchers, led by Sirenda Vong of the Pasteur Institute of Cambodia in Phnom Penh, conducted their study in early 2006, according to the Bloomberg story.
The researchers asked villagers about their exposure to poultry and tested their blood for antibodies to H5N1.
The median age of the seven people who had antibodies was 12 years, compared with 27 years for those who had no antibodies, the story said.
Vong and colleagues had conducted a similar study of 351 Cambodian villagers in 2005 and found that none had antibodies to the virus.
The study was published in Emerging Infectious Diseases in 2006.



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[Giuseppe]

Re: How Dangerous is Bird Flu, H5N1 to Global Public Health?

Re: How Dangerous is Bird Flu, H5N1 to Global Public Health?

(...)

(3) [CAMBODIA, USA, FAO, PANDEMIC PREPAREDNESS] FAO receives $1.9 mln from USAID to fight bird flu in Cambodia
PHNOM PENH, Oct. 18 (Xinhua) -- The Food and Agriculture Organization of the United Nations (FAO) has received an additional 1.9 million U.S. dollars of grant from the United States Agency for International Development (USAID) to control and prevent the spread of the highly pathogenic avian influenza in Cambodia, said a press release here on Thursday.
FAO will use the grant to support ongoing activities of the Ministry of Agriculture, Forestry and Fisheries to control avian influenza at its source in domestic poultry and waterfowl in the next two years, said the FAO release.

"A major component of this project is the training of veterinary staff and village animal health workers (VAHWs) in the techniques of surveillance, and the recognition and systematic recording and reporting of suspected cases," said Dr. Guy Freeland, Team Leader of FAO Avian Influenza Control Programme in Cambodia.
​

FAO will start in November a routine surveillance of wild birds with the U.S.-based Wildlife Conservation Society (WCS), focusing on sites and waterfowl species selected for their association with past outbreaks and the likelihood of mingling or sharing habitat with domestic fowl.

"The aim was to collect and test some 3,000 wild bird samples during this six month period," Freeland said.
​

Cambodia has had 22 outbreaks in poultry since 2004 and seven human deaths. The latest outbreak in poultry and in human was reported in Kampong Cham in April 2007.
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SOURCE

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[CopitoSP]

Re: How Dangerous is Bird Flu, H5N1 to Global Public Health?

Re: How Dangerous is Bird Flu, H5N1 to Global Public Health?

Cambodian birdflu deaths show ongoing threat

Updated February 24, 2011 22:37:03

An expert in global diseases says the death of a Cambodian mother and her baby from bird flu are a timely reminder that the world must not forget about animal influenza. Earlier this month a 5 year old Cambodian girl also died from bird flu - it was the first such death worldwide since early 2010. But it's not just Cambodia that is at risk. Many Asian countries remain vulnerable to animal diseases crossing over to humans.

Reporter: Liam Cochrane

Speakers: Dr Nima Asgari, public health specialist, World Health Organisation, Cambodia; Dr Subhash Morzaria, regional manager, Emergency Centre for Transboundary Animal Diseases, UN Food and Agriculture Organisation

Listen: Windows Media

COCHRANE: Twenty one year old Prak Sophorn and her 11 month old son were visiting relatives in Cambodia's southeast when it is believed they came into contact with sick poultry. They travelled back to their homes on the other side of the country and became sick, but at first bird flu was not suspected.

ASGARI: Our understanding is that the initial symptoms were basically fever, cough, breathlessness, so your classical respiratory infection.

COCHRANE: That's Dr Nima Asgari, a public health specialist with the World Health Organisation in Cambodia. He says only after the Prak Sophorn died on February 12 did doctors check her baby son for bird flu and found both mother and child had contracted H5N1, a strain of bird flu.

Dr Subhash Morzaria, UN Food and Agriculture Organisation's regional manager of the Emergency Centre for Transboundary Animal Diseases, based in Bangkok.

MORZARIA: This is not unusual. When we get outbreaks of disease there are still very poor people who eat sick birds, sometimes not very well cooked and would likely be infected. And this is what's happened in this case.

COCHRANE: Dr Morzaria says any human infection is a concern as it suggests a lack of awareness about handling sick birds. (...)

...


Dr Subhash Morzaria says Japan has emerged as a new risk.

MORZARIA: The virus is being actually spread by wild birds. So we now know that wild birds are infected with highly pathogenic avian influenza, H5N1 virus. And [the wild birds] then shed the virus when they're migrating to Japan. Somehow the virus is then jumping to the poultry and causes these huge outbreaks.

COCHRANE: Bird flu was initially controlled in Japan and this reemergence in a developed nation is a major concern to health workers. But, Dr Subhash Morzaria from the FAO, says most transmissions of bird flu still occur through raising or trading in poultry and he says that is where the resources should stay.

MORZARIA: Moving from that into wild birds is a red herring, I think. We have to be aware that wild birds carry. We have to be aware of the need for biosecurity. (...)

COCHRANE: Dr Morzaria says it is important to maintain a watch for emerging diseases and to make sure existing ones do not reemerge. Developing countries in Asia, with their dependence on agriculture are particularly at risk, says Dr Morzaria, (...) In fact, Dr Morzaria says bird flu is part of wider trend of globalised human behaviour opening the doors for animal diseases.

MORZARIA: About 70 per cent of the animal diseases that emerge are infective to human beings. This particular trend is going to continue because of the human activity. We are intensifying our farming systems, so there is a high population of domestic animals for food consumption. There is high population of human beings. There is increased deforestation. There is greater contact between different animal species and human beings, and this is really going to enhance opportunities for pathogens to jump from one species to another.

COCHRANE: Dr Subhash Morzaria says the most effective prevention will occur if governments work together.



*(...) "..." - Continue reading inside

http://www.radioaustralia.net.au/asiapac/stories/201102/s3148354.htm

 

[sharon sanders]

Re: How Dangerous is Bird Flu, H5N1 to Global Public Health?

Re: How Dangerous is Bird Flu, H5N1 to Global Public Health?

Please see:


Indonesia - West Java - Bird flu in poultry in Garut - 14 individuals suspected with bird flu, 163 being monitored

 

[Laidback Al]

Re: How Dangerous is Bird Flu, H5N1 to Global Public Health?

Re: How Dangerous is Bird Flu, H5N1 to Global Public Health?

Please see:
Indonesia - West Java - Bird flu in poultry in Garut - 14 individuals suspected with bird flu, 163 being monitored

As of today, at least two individuals, an adult and a child, are hospitalized in isolation and being treated for symptoms of bird flu infection in Garut Regency while the status of hundreds more individuals are being monitored by public health officials in the area. Even after several days and enough time to analyze tests, health officials have failed to confirm or deny H5N1 infections in these patients.

Today, WHO reported three new H5N1 cases from Egypt. One of the patients died, one was treated and released, and one is apparently still being treated in the hospital. The 26 year old patient that was released on February 7 was treated for 15 days. The 4 year old boy from Damietta Governorate has been hospitalized for 12 days and is still only listed in stable condition.

Long treatment and recovery periods in the hospital are the norm for H5N1 infected patients, assuming they recover. Numerous post here at FluTrackers confirm that recovery for serious ill H5N1 patients is a long process and generally requires intensive care.

The public health concern for an H5N1 pandemic is that hospitals will be overrun and unable to care for a majority of the sickest patients. The 2009 pandemic stretched health care providers in many regions and yet was not considered an exceptionally virulent or high mortality strain. In fact, in some areas the mortality rate from p(H1N1) was even lower than for seasonal influenza.

If H5N1 reassorts into a pandemic strain, and even if its CFR decreases, it could still cause devastating public health issues if it takes weeks and weeks of hospitalization to survive.

 

[Laidback Al]

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Why do most of the people that contract H5N1 in Indonesia die?

From the Garut thread about suspected human infections in Indonesia.

Head of the Isolation Room, Wawa Sumiarsa, MCA and Chief Information Subag Dr. Slamet Garut, R. Awang Wangsadinata to Garut News, suggested that moved both patients recovered, but still not be allowed to go home.

Because waiting for the results of Research and Development Kemenkes, following Mrs. AK indicated never in contact with the H5N1 positive poultry, and young children (LA) the possibility of environmental exposure to the many cattle died suddenly, he said.

http://www.flutrackers.com/forum/showpost.php?p=396498&postcount=87

Now these two suspected individuals are recovering after Tamiflu treatment. The second paragraph is setting the stage for an announcement that neither of these individuals were infected with H5N1. Note that the notice from DEPKES today only identifies one confirmed human case of H5N1 in Indonesia since November of 2010, and that individual died. It is suspicious that only people who die are ever confirmed with H5N1 in Indonesia. Since January 1, 2010, 10 people in Indonesia have been confirmed with H5N1. Eight died.

 

[Laidback Al]

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

More Indonesian H5N1 Deaths

While the world is watching the crises in Japan unfold, Bird Flu continues to be an ever present threat with the potential to spark a pandemic that could be a similar tragedy.

WHO has now confirmed two more deaths from H5N1 in Indonesia. No media reports about either of these two individuals were noted by FluTrackers members in February. In the post above I commented on the unusual fact that only patients who are infected with H5N1, and die, are ever reported by Indonesia as H5N1 cases.

The FluTrackers team has been following H5N1 poultry outbreaks in two areas, Garut, West Java and Pandang, West Sumatra. In both of these areas large numbers of individuals exhibited H5N1 influenza symptoms, some serious enough to be hospitalized, and all were treated with Tamiflu. None of the symptomatic individuals that were treated died. Treated individuals were allowed to go home after they improved.

So far, none of these individuals are considered H5N1 cases, not even those who test positive in the rapid test. I speculate, with some degree of confidence, that none of the survivors will ever be officially reported as confirmed H5N1 cases. But that does not mean they weren't infected with H5N1.

 

[Gert van der Hoek]

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

This post of CopitoSP could explain why human H5N1 cases can be missed?

Oropharyngeal swab specimens and lower respiratory tract specimens (e.g., bronchoalveolar lavage or tracheal aspirates) are preferred because they appear to have the highest quantity of virus for H5N1 detection and Nasal or nasopharyngeal swab specimens contain less virus and therefore not be optimal for virus detection.

(...)

This is one of the things we need to track for major changes in H5N1 epidemiology. Up to date most bird flu infections are negative in rapid test and then confirmed by lower respiratory tract specimens in laboratory, this is mainly due to a better adaptation to 2-3 sialylated glycans in bird flu strains, including H5N1 currently in circulation.

But, now in the last months we're seeing more cases confirmed by upper respiratory tract specimens in endemic regions. What we don't know if this is due to new protocols for testing or a change in the virus that allows it to bind to 2-6 sialylated glycans better. Sequences from latest cases would be very useful.

A mild course of infection with H5N1 is nothing new, but in fact it's estimated that if H5N1 sparks the new pandemic will be far less severe than the current case fatality rate known, it will be at 5% to 10% (this is a worst case scenario). Of course influenza is unpredictable and a severer or milder pandemic might emerge. It's well known that many bird flu cases go underreported, not only because governments failing at providing a better infrastructure or not sharing publicly this information, but also because of mild infection like in Bangladesh or some others in Egypt.

Right now, Indonesia is something to keep an eye as some patients have tested positive for influenza by rapid test and they had a mild infection where sick and dead poultry is being reported daily.Indonesia don't like to report these cases , so we won't know the results unless an epidemic begins in the area and maybe it also will take some time.

 

[Laidback Al]

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Why is it that Indonesia never reports diagnoses for "suspected bird flu" survivors?

I speculated on March 14th that more suspected bird flu cases in Indonesia would not be confirmed for H5N1. Now, all of the suspected bird flu patients in Pandang have been pronounced negative (see this thread)

19 Suspected Bird Flu in Padang Negative

Friday, March 18, 2011

REPUBLIKA.CO.ID, JAKARTA - The Ministry of Health (Kemenkes) said 19 patients with suspected (suspected) bird flu in Padang, West Sumatera (Sumatra), there has been no positive bird flu after tests. "Nineteen patients were suspected, no one has been positive," said Director General of Disease Control and Environmental Health (P2PL) Tjandra Yoga Aditama in Jakarta, Friday (18 / 3).

So, it was not unexpected that Indonesia would announce all of these survivors as "negative for bird flu". However, the health officials could regain some credibility if they reported actual diagnoses for these cases. At least nine of these individuals were treated at the hospital, sometimes for days, and the high fever and other symptoms identified in the media reports are certainly symptoms characteristic of influenza. Dozens of sick individuals and the public health officials have no idea what the cause is? Of course, maybe they do know and they aren't willing to report the truth.<o></o>

 

[sharon sanders]

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Please see:

Indonesia - Java - Suspected bird flu death reported from Yogyakarta

Indonesia - "Positive human cases in Garut, Depok,Bekasi and Indramayu"

Indonesia ::: Ministry of Health announces additional H5N1 victim

 

[Laidback Al]

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Some Reasons to be Optimistic About H5N1 Infections in Egypt

In the past nine days WHO has confirmed seven human H5N1 infections in Egypt (Update 48 and Update 49), one in February and six in March. So far only one of the seven has died, four have been released from the hospital, and two are apparently still hospitalized and in stable condition.

What gives rise to optimism is that three of the released individuals are all children four years old or younger. More importantly, all three of these individuals were only treated for 5-6 days before being released. In contrast, the two individuals that are still hospitalized are young female adults (ages 28 and 34) who have been hospitalized for 14+ days. And the fourth released patient is a 30 year old female who was hospitalized for 12 days before being released.

The general consensus is that young children (less than 5 years of age) are at higher risk for morbidity and mortality from influenza infections, yet these few H5N1 cases from Egypt contradict this observation. The fact that H5N1 is a novel influenza strain confuses the situation even more.

Whether it is the antiviral treatment strategy for H5N1-infected children in Egypt or a less virulent strain circulating there deserve further epidemiological scrutiny. I leave it to the virologists to examine the possibility that the immunological response system of children has not yet been sufficiently primed (overwhelmed?) by H1N1 or H3N2, and that these young Egyptian children can ward off an H5N1 infection with the help of antivirals.

Whatever the situation, it is encouraging news that children in Egypt are surviving H5N1 infections.

 

[Laidback Al]

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Egypt Earth Day Photo and H5N1 Infections

Egypt has reported 24 human cases of H5N1 so far this year, double the total number of human cases from all other countries in 2011 combined. Egypt is second only to Indonesia in number of confirmed human H5N1 cases among the world's countries.

Most of the human H5N1 cases in Egypt are concentrated in the heavily populated Nile Delta area in the north. This area is one of the most densely populated areas in the world. This NASA photo, posted on behalf of Earth Day today, was taken from the International Space Station in 2010 (link)



This photo dramatically shows how densely populated the Nile Delta is, all 40 million people.

If H5N1 becomes easily transmissible in this area, it seems obvious that there would be no way to stop transmission and the world would be facing another pandemic.

 

[Giuseppe]

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

The WHO has released a study about 2010 human H5N1 cases.

[Source: World Health Organization, Weekly Epidemiological Record, full PDF document (LINK). Extract, edited.]


Weekly epidemiological record
Relev? ?pid?miologique hebdomadaire
22 APRIL 2011, 86th year / 22 AVRIL 2011, 86e ann?e
No. 17, 2011, 86, 161?172
http://www.who.int/wer

Update on human cases of highly pathogenic avian influenza A(H5N1) virus infection, 2010


This report describes the epidemiology of the 48 human cases of symptomatic illness caused by laboratory confirmed infection with influenza A(H5N1) virus that were reported to WHO during 2010. All 48 cases occurred as sporadic cases, with no clusters reported.


Temporal and geographical distribution:

Although cases occurred throughout the year there was a marked seasonal variation with the peak occurring between December and March, during the northern hemisphere winter (Figure 1). In 2010, most human cases occurred in the northern hemisphere ? with the exception of those in Indonesia, which straddles the equator ? in both temperate and tropical areas. The number of cases in individual countries was too small to determine whether seasonality differed among countries with different climates. The seasonal variation in human cases parallels that of outbreaks in birds.(1)

The highest number of cases was reported from Egypt (29 cases), followed by Indonesia (9), Viet Nam (7), China (2) and Cambodia (1). All of these countries have reported human cases previously, including in 2009,(2, 3) and all are countries where influenza A(H5N1) virus is believed to be circulating widely in poultry. Egypt and Indonesia have officially declared the virus endemic in poultry,(4) and information from the United Nations Food and Agriculture Organization suggests that the influenza A(H5N1) virus is also endemic in poultry in Viet Nam and parts of China as well as in Bangladesh.(5) In Cambodia the virus appears to be reintroduced sporadically in poultry.



Distribution by sex and age

In 2010 most cases occurred in children and young adults; 83% (40/48) of cases occurred in people aged <40 years (Figure 2). Cases ranged in age from 1?59 years, with a median age of 25 years. The median age of cases in 2010 was slightly higher than the median of 19 years for all cases from all countries since 2003. Egypt in 2010 had a higher median age of 27 years compared with a median age of 3 years in 2009, and 10 years for all previous years combined. In 2010, there were half as many cases in male than in females (ratio of male to female cases, 1:2), although this difference was not uniformly distributed among countries nor was the sex distribution consistent among age groups. Females made up a much larger proportion of cases aged 20?29 years, which is consistent with data from previous years. The sex difference in 2010 was most notable in Indonesia (ratio of males to females, 1:8) and for Viet Nam (ratio of males to females, 1:6). In contrast, cases in Egypt were more evenly distributed: the ratio of males to females was 1:1.2. Historically, when all cases from all countries are considered, the sex of cases is almost equally distributed between males and females (ratio of males to females, 1:1.1).



Outcomes

Half (n = 24) of the 48 cases died. The case-fatality ratio (CFR) differed by country: Viet Nam had the lowest CFR (7 cases; CFR, 28%). For all countries in 2010, women had a higher CFR than men (56% versus 38%). There have been 516 cases since 2003, and the CFR has been higher for women for all years taken together (65% versus 53%); however, this difference has not been observed in every country and may be related to factors such as age.

During 2010, the CFR was highest among those aged 30?39 years (CFR, 70%) and lowest among those aged 0?9 years (CFR, 30%), but the difference was not significant. When all 516 cases from 2003 to 2010 are included, cases aged <20 years have a significantly lower risk of dying than those aged >20 years (CFR 52% versus 66%; OR, 0.56; 95% CI, 0.39?0.81); however, this observation is not consistent for every country.



Time from onset to hospitalization

The time from onset of illness to hospitalization was available for 42 cases; it ranged from 0 days to 12 days, with a median of 4 days. Cases that died were admitted to hospital later (median, 5 days) after onset than those who survived (median, 2 days). The CFR for cases who were hospitalized within ≤2 days of onset was lower than for those hospitalized >2 days after onset (CFR, 25% versus 65%; OR, 5.6; 95% CI, 1.4?22.7). For all cases from all years, those who died were hospitalized later than those who survived (median 5 days after onset versus 2 days; Kruskal?Wallis test P = 0.0001), and when cases were hospitalized ≤2 days from onset they were more likely to survive than those hospitalized >2days after onset (CFR, 29% versus 71%; OR, 5.9; 95% CI, 3.7?9.3).



Exposure data

Data on exposure were available for 37 cases. In 32 of the cases, exposure to sick or dead poultry was noted; no other exposures were reported. Of the cases reporting exposure to sick or dead poultry, 4 were reported to have slaughtered poultry and 2 disposed of dead poultry.
Three cases were associated with occupational exposure:

• 1 worked with fertilizers of animal origin, 1 worked in a live-bird market and 1 worked slaughtering and defeathering poultry.

Two of the 37 for whom data on exposure were available reported being exposed in live-bird markets. Data on exposure were inconclusive or unavailable for 11 cases. However, poultry, some of which were sick, were reported to have been present near the households of 5 of these cases.



Virological information

Influenza A(H5N1) viruses have continued to diversify, both genetically and antigenically. During 2010, viruses characterized from human cases belonged to clade 1 (Cambodia), clade 2.2.1, group C (Egypt), clade 2.3.2 (China, Hong Kong Special Administrative Region), and clade 2.3.4 (Viet Nam). Viruses from these clades have also been isolated from poultry in each country.(6) None of 9 human isolates from 2010 that have been sequenced had the neuraminidase mutations known to predict resistance to oseltamivir.



Discussion

Human infection with influenza A(H5N1) virus remains uncommon and sporadic despite continued widespread circulation of the virus in poultry in some countries. As in previous years, countries reporting human cases were those where the virus circulates in poultry; there continues to be no evidence of sustained human-to-human transmission. The general epidemiological picture of human cases of infection with influenza A(H5N1) is unchanged.

Women seem to have a worse outcome than men, and the disease appears more likely to be mild in children. Overall, children and young adults seem to be more frequently diagnosed with the infection, although the median age increased in 2010, primarily in association with an increase in the age of cases in Egypt. Early recognition of infection and hospitalization are likely to lead to favourable outcomes. A recent analysis of 119 cases occurring in Egypt since 2006 reaffirms these observations.(7) Investigators there found a significant increase in CFR with the age of the case and among females when compared with males. In addition, early hospitalization was found to have a positive impact on survival. WHO continues to recommend that clinicians in endemic countries be encouraged to consider influenza A(H5N1) infection when patients present with compatible clinical and epidemiological features, and to treat patients early with appropriate antiviral medications.(8)

The influenza A(H5N1) virus remains an avian virus that has not substantially changed in its zoonotic behaviour since emerging. The genetic and antigenic diversification of circulating influenza A(H5N1) viruses, however, require the development of multiple candidate vaccine viruses for purposes of pandemic preparedness. There are no signs of increasing antiviral resistance to oseltamivir in influenza A(H5N1) viruses or reassortment with any of the circulating human influenza viruses.

Most human cases are exposed through direct or indirect contact with poultry or contaminated environments and, as in previous years, the exposures that result in symptomatic infection happen almost exclusively in households or markets rather than in association with commercial poultry. People who are infected are often reported to have slaughtered or prepared birds for consumption, and visits to live-bird markets continue to be reported as potential venues for exposure to infection. However, in most of the areas where human cases have been reported, multiple exposures to potentially infected poultry or to environments where poultry live are a routine part of daily life. Because of this, it is difficult to determine which specific exposures lead to human infection and disease. It is therefore important for animal health and public health partners to continue to work together to identify and manage common risks and to decrease human exposure at the human?animal interface, particularly in households and in live-bird markets. Because some risk of human exposure will remain as long as the virus circulates widely among poultry, it is also important that the animal health sector continues its efforts to control the virus at its source ? that is, in animal populations.

Current knowledge about influenza A(H5N1) infection in humans has been acquired thanks to the countries that have collected and openly shared information about their cases. WHO would like to recognize the contribution of the countries which reported cases in 2010. However, there is a need to do more, both in terms of comprehensive data collection, contextual analysis, and the sharing of linked virological, epidemiological and clinical data. There are still unanswered questions about the epidemiology of the disease in animals, and these are being addressed by the animal health sector. In addition, there are specific issues about the disease in humans and at the human?animal interface that need to be addressed through targeted research, including clearly identifying the factors that facilitate transmission to humans, further defining the spectrum of illness and the magnitude of mild or asymptomatic disease, and identifying the virological and genetic markers for transmissibility and virulence in humans. Finally, laboratories which identify influenza A viruses that are not seasonal subtypes are encouraged to submit these samples immediately for further characterization to a WHO Collaborating Centre on influenza.(9)

1. See H5N1 HPAI global overview May/June 2010. FAOAIDEnews, 2010, 69:5?19 (LINK), accessed 4 April 2011).
2. See No. 46, 2008, pp. 413?420.
3. See No. 7, 2010, pp. 49?56.
4. World animal health information database: summary of immediate notifications and follow-ups ? 2010. Paris, World Organisation for Animal Health, 2011 ((LINK), accessed 4 April 2011).
5. Global Programme for the Prevention and Control of Highly Pathogenic Avian Influenza: third report. Rome, United Nations Food and Agriculture Organization, 2010 ((LINK), accessed 4 April 2011).
6. See No. 11, 2011, 93?100.
7. Kayali G et al. The epidemiological and molecular aspects of influenza H5N1 viruses at the human-animal interface in Egypt. PLoS One 2011, 6(3): e17730; doi:10.1371/ journal.pone.0017730.
8. WHO rapid advice guidelines on pharmacological management of humans infected with avian influenza A (H5N1) virus: May 2006. Geneva, World Health Organization,2006 (also available at (LINK)).
9. Selection of clinical specimens for virus isolation and of viruses for shipment from National Influenza Centres to WHO Collaborating Centres ? revised: 6 Dec 2010. Geneva, WHO Global Influenza Programme, 2010 ((LINK), accessed 4 April 2011) .

(?)
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[Laidback Al]

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Retrospective Analysis of Human to Human to Human Transmission of H5N1 in Pakistan in 2007

The article below from Emerging Infectious Disease affirms H2H2H spread of H5N1 in Pakistan in late 2007. FluTrackers members noted and reported on numerous potential cases at that time based on media reports (link and link). These concerns were never investigated and WHO only officially confirmed 3 human cases of H5N1 at the time (link and link).

Four years later, this analysis indicates that human to human to human transmission probably occurred along with nosocomial infection of H5N1. The authors conclude ?Taken together, these features suggest that current surveillance might undercount the extent of human infection with influenza (H5N1) virus and that human-to-human transmission might possibly be associated with less severe disease.?

Indeed, we have every reason to believe that underidentification of human H5N1 cases, especially cases with mild symptoms, is occurring. But that is no justification for underreporting of human H5N1 or to cut back on H5N1 surveillance. Hoping that any H5N1 pandemic will be a mild one is not a good public health strategy. Research into H5N1 vaccine development, production, and distribution needs to be our highest priority to avoid a bird flu pandemic.

----------------------------------

Volume 17, Number 6?June 2011

Dispatch

Human Infection with Avian Influenza Virus, Pakistan, 2007

Mukhtiar Zaman, Saadia Ashraf, Nancy A. Dreyer, and Stephen Toovey
Author affiliations: Khyber Teaching Hospital, Peshawar, Pakistan (M. Zaman, S. Ashraf); Outcome Sciences, Cambridge, Massachusetts, USA (N.A. Dreyer); and University College and Royal Free Medical School, London, UK (S. Toovey)
Suggested citation for this article
Abstract
Human infection with avian influenza (H5N1) virus raises concern for the possibility of a pandemic. We report 20 cases, which ranged from asymptomatic to fatal, in Pakistan in 2007. These cases indicate human-to-human-to-human transmission of this virus, and the number of cases may be higher than realized.

<table width="150" align="right" border="0" cellpadding="5" cellspacing="0"><tbody><tr><td bgcolor="#D8ECEB">

Figure 1​

</td></tr><tr><td bgcolor="#D8ECEB">

</td></tr><tr><td bgcolor="#D8ECEB">Figure 1. Areas of influenza (H5N1) cases in humans, Pakistan, 2007...
</td></tr><tr><td>
</td></tr><tr><td bgcolor="#D8ECEB">

Figure 2​

</td></tr><tr><td bgcolor="#D8ECEB">

</td></tr><tr><td bgcolor="#D8ECEB">Figure 2. Path of infection of influenza (H5N1), Pakistan, 2007...
</td></tr></tbody></table> Evidence of human-to-human transmission of influenza A (H5N1) virus raises concern over a possible pandemic (1). Previous epidemiologic investigation of the outbreak of influenza (H5N1) among persons in the Northwest Frontier Province of Pakistan (Figure 1) in 2007 found 5 cases?3 confirmed, 1 asymptomatic, and 1 probable?as defined by the World Health Organization (WHO) (2). We report a larger set of 20 cases during this outbreak in Pakistan, supporting human-to-human-to-human transmission.
The Cases

Records were examined from all hospitals that treated patients with influenza (H5N1) virus in Northwest Frontier Province during 2007. Data were rendered anonymous and entered into a secure database with predetermined clinical and epidemiologic fields. Cases matching predefined criteria (Table 1) were classified as laboratory confirmed, likely, or possible. Cases not meeting classification criteria were excluded. We slightly modified WHO criteria to resemble criteria that clinicians might adopt during an actual outbreak, especially in a resource-poor setting (3).
We identified 20 cases?4 laboratory confirmed, 7 likely, and 9 possible?resulting in a ratio of 4 likely/possible cases for each laboratory-confirmed case. Median age was 29 years (range 7?60 years) for all patients and 30 years (range 23?35 years) for confirmed case-patients; 16 (80%) patients were male. The infecting exposure could not be established for all patients because multiple exposures, human and avian, were recorded for some. Of the 4 patients with laboratory-confirmed cases, 3 were treated with oseltamivir (2 [67%] of whom survived), and 1 had asymptomatic disease and received no antiviral treatment.
Signs and symptoms were mainly those of a febrile influenza-like illness (Table 2), although 1 patient with a laboratory-confirmed case was asymptomatic (microneutralization titer 320, Western blot positive, throat swab positive for H5 by reverse transcription?PCR); this case-patient was also described in a previous epidemiologic investigation (2). Gastrointestinal signs and symptoms were not prominent, and neurologic signs were not reported.
The first 8 cases constituted a cluster (Figure 2). The index case-patient (patient 1) had culled influenza (H5N1) virus?infected poultry. After becoming febrile (38?C) while in Abbottabad, he traveled by public transportation to his family home in Peshawar. His illness progressed and on November 5, 2007, he was admitted to Khyber Teaching Hospital, where the diagnosis of influenza (H5N1) infection was made. Infection appeared to spread initially from household family contacts (patients 2?6) to medical staff (patient 7, who had positive PCR but negative microneutralization test results) and to a frequent visitor to the intensive care unit (patient 8).
As previously noted (2), the extended period from the time persons were exposed to the index case-patient, during which family members became ill, points to human-to-human-to-human transmission; patient 2 probably accounted for intermediary or second-generation infection. The chain of infection illustrated in Figure 2 suggests that further human-to-human-to-human transmission might have occurred and suggests nosocomial transmission. Of note, patient 6 (a cousin of the index case-patient) had a microneutralization titer of 80 but a negative Western blot result. Although 4 contacts of patient 6 exhibited no signs or symptoms of influenza, they did have positive H5 microneutralization titers ranging from 80 to 160.
No evidence epidemiologically links the remaining 12 patients to the 8 patients in the cluster; each of the 12 either had direct contact with influenza (H5N1) virus?infected poultry or was near healthy or diseased poultry before symptom onset. Three patients worked on poultry farms: 1 had taken a sample from an influenza (H5N1) virus?infected chicken, 1 was directly involved in culling, and 1 was indirectly exposed to live poultry. Eight patients had negative test results for influenza (H5N1) virus, and 3 had positive results from the National Institute of Health Islamabad but negative confirmatory-testing results from WHO; 1 patient died before samples could be taken. Different laboratories reported conflicting results with respect to confirmation of infection, possibly because of the difficulties of complying with specimen-handling requirements in resource-poor settings. Clinical details of these cases are shown in Table 2.
Conclusions

The preponderance of male patients is probably explained by sociocultural factors; the index case-patient was a poultry culler, a male-dominated task, and shared accommodation with male family members. Health care?seeking behavior may also account for this finding.
The human-to-human transmission from the index case-patient to at least some household contacts seems clear, and the extended period over which these contacts became ill supports subsequent human-to-human transmission. Figure 2 supports the conclusion that patient 2 initiated a chain of infection in which further human-to-human transmission to patients 7 and 8 occurred. Possible nosocomial transmission is of concern because full implementation of isolation procedures in resource-poor settings may be problematic.
Although virologically supported probable human-to-human transmission of influenza (H5N1) virus has been documented, it has been thought to occur only with prolonged and close contact (4). Household clustering and the difficulty of establishing exact virus exposures have encumbered efforts to investigate possible human-to-human transmission (5). Modeling has (6) suggested human-to-human transmission in Indonesia, but the utility of statistical modeling unsupported by field data has been questioned (7).
Although the index case-patient traveled by public transportation from Abbottabad, where he acquired his infection, no infections were reported for anyone other than household contacts, who were all related and exposed at his family home at Peshawar. In contrast, patients 2 and 6 might have spread infection through less intimate contact, which raises 2 questions. Might some persons shed virus more efficiently than others, possibly in greater quantity? And what role might host factors play in susceptibility to influenza (H5N1) virus infection and disease? A degree of virus adaptation to humans might also have occurred, although absence of sustained community transmission argues against this possibility.
Of concern is the 4:1 ratio of likely/possible to laboratory-confirmed cases, suggesting that official tallies understate true incidence of infection. Factors that may contribute to undercounting are the difficulty of obtaining virologic confirmation or of storing and transporting samples in resource-poor settings and reluctance by relatives to consent to autopsy. Another reason to believe that less fulminant cases may go unreported is the occurrence in Pakistan, and elsewhere, of clinically mild and asymptomatic cases (5,8?14), indicating that influenza (H5N1) virus may cause a spectrum of illness. The demonstration during the 1997 Hong Kong outbreak of influenza (H5N1) with seroconversion in apparently asymptomatic health care workers and social contacts suggests human-to-human transmission, although in Hanoi, no transmission to health care workers was detected (8,13,15). Also contributing to underreporting are the predominant clinical signs of undifferentiated influenza-like illness observed in Pakistan and elsewhere, which, unless clinical deterioration occurred, would be unremarkable in many tropical settings. Although the survival rate was greater for patients who received oseltamivir, the small number of patients and the inclusion of those with mild and asymptomatic illness prevent meaningful statistical comparison.
Several features of the outbreak are unusual or give cause for concern: human-to-human-to-human transmission, possible nosocomial transmission, occurrence of mild and asymptomatic cases, and difficulties of establishing laboratory confirmation of likely and possible cases (which also prevented genotypic matching of specimens from primary and putative secondary cases). Taken together, these features suggest that current surveillance might undercount the extent of human infection with influenza (H5N1) virus and that human-to-human transmission might possibly be associated with less severe disease.

Dr Zaman is a consultant pulmonologist and head of the Pulmonology Department, Khyber Teaching Hospital, Khyber Medical College, Peshawar, Pakistan, and general secretary of the Pakistan Chest Society. His research interests include chronic obstructive pulmonary disease, nutrition, tobacco addiction, and coal workers' pneumoconiosis.
​

References

1. Olsen SJ, Ungchusak K, Sovann L, Uyeki TM, Dowell SF, Cox NJ, et al. Family clustering of avian influenza A (H5N1). Emerg Infect Dis. 2005;11:1799?801.
2. World Health Organization. Human cases of avian influenza A (H5N1) in North-West Frontier Province, Pakistan, October?November 2007. Wkly Epidemiol Rec. 2008;83:359?64.
3. World Health Organization. WHO case definitions for investigation of human infections with influenza A(H5N1) virus. Geneva: The Organization; 2006.
4. Wang H, Feng Z, Shu Y, Yu H, Zhou L, Zu R, et al. Probable limited person-to-person transmission of highly pathogenic avian influenza A (H5N1) virus in China. Lancet. 2008;371:1427?34. PubMed DOI
5. Kandun IN, Wibisono H, Sedyaningsih ER, Yusharmen, Hadisoedarsuno W, Purba W, et al. Three Indonesian clusters of H5N1 virus infection in 2005. N Engl J Med. 2006;355:2186?94. PubMed DOI
6. Yang Y, Halloran ME, Sugimoto JD, Longini IM Jr. Detecting human-to-human transmission of avian influenza A (H5N1). Emerg Infect Dis. 2007;13:1348?53.
7. Uyeki TM, Bresee JS. Detecting human-to-human transmission of avian influenza A (H5N1). Emerg Infect Dis. 2007;13:1969?71.
8. Buxton Bridges C, Katz JM, Seto WH, Chan PK, Tsang D, Ho W, et al. Risk of influenza A (H5N1) infection among health care workers exposed to patients with influenza A (H5N1), Hong Kong. J Infect Dis. 2000;181:344?8. PubMed DOI
9. Chan PK. Outbreak of avian influenza A(H5N1) virus infection in Hong Kong in 1997. Clin Infect Dis. 2002;34(Suppl 2):S58?64. PubMed DOI
10. Oner AF, Bay A, Arslan S, Akdeniz H, Sahin HA, Cesur Y, et al. Avian influenza A (H5N1) infection in eastern Turkey in 2006. N Engl J Med. 2006;355:2179?85. PubMed DOI
11. Vong S, Ly S, Van K, Achenbach J, Holl D, Buchy P, et al. Risk factors associated with subclinical human infection with avian influenza A (H5N1) virus?Cambodia, 2006. J Infect Dis. 2009;199:1744?52. PubMed DOI
12. Yuen KY, Chan PK, Peiris M, Tsang DN, Que TL, Shortridge KF, et al. Clinical features and rapid viral diagnosis of human disease associated with avian influenza A H5N1 virus. Lancet. 1998;351:467?71. PubMed DOI
13. Katz JM, Lim W, Bridges CB, Rowe T, Hu-Primmer J, Lu X, et al. Antibody response in individuals infected with avian influenza A (H5N1) viruses and detection of anti-H5 antibody among household and social contacts. J Infect Dis. 1999;180:1763?70. PubMed DOI
14. Brooks WA, Alamgir AS, Sultana R, Islam MS, Rahman M, Fry AM, et al. Avian influenza virus A (H5N1), detected through routine surveillance, in child, Bangladesh. Emerg Infect Dis. 2009;15:1311?3. PubMed DOI
15. Liem NT, Lim W. Lack of H5N1 avian influenza transmission to hospital employees, Hanoi, 2004. Emerg Infect Dis. 2005;11:210?5.

Figures

Figure 1. Areas of influenza (H5N1) cases in humans, Pakistan, 2007...
Figure 2. Path of infection of influenza (H5N1), Pakistan, 2007...
Tables

Table 1. Case classification definitions used to diagnose influenza (H5N1) infection in humans, Pakistan, 2007
Table 2. Clinical characteristics for persons with reported cases of influenza (H5N1), Pakistan, 2007
Suggested Citation for this Article

Zaman M, Ashraf S, Dreyer NA, Toovey S. Human infection with avian influenza virus, Pakistan, 2007. Emerg Infect Dis [serial on the Internet]. 2011 Jun [date cited]. http://www.cdc.gov/EID/content/17/6/1056.htm
DOI: 10.3201/eid1706.091652

http://www.cdc.gov/eid/content/17/6/1056.htm

 

[crayonfish]

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

"Taken together, these features suggest that current surveillance might undercount the extent of human infection with influenza (H5N1) virus and that human-to-human transmission might possibly be associated with less severe disease."

That's definitely something positive to consider.

 

[sharon sanders]

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

We have absolutely no transparency into the H5N1 situation in Egypt. The Ministry of Health claims 27 cases and 9 deaths year-to-date 2011. We have charted 25 cases and 8 deaths, which corresponds to the WHO totals.

Since the revolution in Egypt this year, the news coverage has been mostly centered on those events and not disease outbreaks.

We are completely in the dark regarding disease status in Egypt.

 

[Laidback Al]

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Will the number of human H5N1 infections in 2011 exceed last year's total?

Today, a potential family cluster of four suspected H5N1 infections was announced in West Sumatra, Indonesia (link). And yesterday, WHO confirmed an additional five H5N1 cases from Egypt (link). If the four cases from Indonesia are confirmed, then the total number of human H5N1 cases during the first half of 2011 will be 49. During all of last year only 48 cases of H5N1 were confirmed by WHO.

With six months remaining in the year, it seems likely that the number of worldwide human H5N1 infections in 2011 is certainly going to exceed last year's total. Continued vigilance is necessary for this potential pandemic virus.

 

[Laidback Al]

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Re: How Dangerous is Bird Flu (H5N1) to Global Public Health?

Human H5N1 clusters in Indonesia

An article has been recently published about the geographic clustering of human H5N1 cases in Indonesia between 2005 and 2007. See this FluTrackers link and the link to the original abstract (link). This article seems to be a revision of the senior author’s thesis project (Mrs. Putri Chairani H. Eyanoer) from 2009 (link).

The study focuses exclusively on geographic and spatial clusters of human cases in Indonesia with an emphasis on three provinces on the island of Java in areas with high infection rates among poultry. The authors avoid the critical question of clustering due to human-to-human transmission, especially among family groups.

It is perhaps unfair to comment on the content of the article based solely on the abstract that is publicly available on the internet. But the author’s conclusion - “These findings are important since they highlight areas of high risk for possible human H5N1 infection in Indonesia, thus, preventive measures may be taken.” – are timid and fall short of positive recommendations.

Based on WHO confirmed cases, there is no doubt that most human H5N1 infections around the world results from contact with sick or dead poultry infected with H5N1. And every year since 2006 fewer and fewer human H5N1 cases are being reported by Indonesia to WHO as required by International Health Regulations (see graph below), even though H5N1 is endemic among poultry throughout Indonesia. The low numbers of human infections that are currently being reported from Indonesia are suspect.



Geographical clustering of cases in Indonesia is not nearly as important as tracking clusters relating to human-to-human transmissions. The apparent virulence of H5N1 strain(s) circulating in Indonesia causing a high CFR is also cause for alarm. Vigilance is necessary to identify H2H H5N1 clusters wherever they occur in the world. Such events could lead to a world-wide H5N1 pandemic.