H5N1

Coston: Bird flu reports from India, Japan, Korea and Taiwan

On his blog Avian Flu Diary, Mike Coston writes: Bird Flu Reports From India, Japan, Korea & Taiwan. This is the kind of post that makes him one of the best in Flublogia: informative and documented, putting his subject in perspective. Excerpt: 

Between 2004 and 2007 the H5N1 avian flu virus expanded its range, going from basically being a problem for a handful of Southeast Asian countries, to being a problem for much of Europe, Asia, and the Middle East.  We saw huge wild bird die offs in China, Indonesia, and Eastern Europe, along with thousands of poultry infestations and culling operations.     

Along the way, several hundred humans were infected as well.   

In 2008, H5N1’s expansion seemed to halt, and in many places the virus actually receded, leaving behind about a dozen places around the world where the virus remained entrenched. Among them were Indonesia, Vietnam, Egypt, Cambodia, India, Pakistan, Bangladesh, and China. 

Even in these countries, the number of outbreaks reported – and the number of human infections – dropped markedly, with the peak reached in 2006 (n=115) and steadily dropping since then (2013= 39 cases). The foci of infections also shifted away from Vietnam and Indonesia towards Egypt and Cambodia. 

While never quite going away, it seemed as if the avian flu threat was simply fading away.

That is, until a new avian flu virus – H7N9 – appeared abruptly in China in the spring of 2013 sparking two consecutive winter epidemics, and is expected to return again this winter as well.  In quick succession, several more avian flu viruses appeared – including H5N8 in Korea (now spread to Europe & Japan), H5N6 in China and Vietnam, H5N3 in China, and H10N8 in China.   

Now, instead of one avian flu threat, we have anywhere from three to six to keep track of (H5N1, H7N9, H5N8, H5N6, H5N3, H10N8), and no one should be terribly surprised if several more novel reassortants emerge over the next couple of years. 

Egypt: Garbage, pigs, and H1N1

Peter Hessler wrote some extraordinary books and articles about modern China, and then moved to Egypt. Thanks to my friends and colleagues Joan Acosta and Azza Sedky for sending me the link to his latest report in The New Yorker: What the Garbageman Knows. It's superbly written and will teach you more about Egypt than you ever thought you needed to know. And it has this passage:

In the thirties and forties, a new wave of migrants began to come from Asyut, in Upper Egypt. They were Coptic Christians, which meant that they could raise pigs that ate organic garbage. The Christians subcontracted from the Muslim wahiya [garbage collectors], who evolved into middlemen, managing access and collecting fees. The actual hauling and sorting was done by the Christians, who became known as zabaleen, and who made much of their income by selling pork, mostly to tourist hotels. 

The government played no role in establishing this system, which worked remarkably well. Social scientists often cite it as a success story among developing-world megacities, and in 2006 an article in Habitat International described it as “one of the world’s most efficient resource recovery” systems. 

It was estimated that the zabaleen recycled roughly eighty per cent of the waste that they collected. But the system became a victim of dysfunctional national politics under the regime of Hosni Mubarak. 

In 2009, during the worldwide epidemic of H1N1 swine flu, the Ministry of Agriculture decreed that all Egyptian pigs had to be killed. There was no evidence that pigs were spreading the disease, but the government went ahead and slaughtered as many as three hundred thousand animals. Some Egyptians believe that the decision was driven by a desire to appease Islamists, who had become outspoken critics of the regime, and supposedly hated pigs even more than they hated Mubarak. 

But the policy backfired, with hundreds of furious zabaleen taking part in protests. They also started tossing organic waste into the streets, because it had no value without pigs. The declining hygiene of the capital and the unrest of the zabaleen were part of the general unhappiness that culminated in the revolution, in January, 2011.

I posted a lot about the pig slaughter back then, and about the consequences Hessler describes.

China: Details on last year's fatal H10N8 case

Via News.92jn.com: H10N8 our first case of bird flu is now causing deaths. Excerpt from a Google translation:

Yesterday, the Ministry of Health and Family Planning Commission news, the China CDC testing, Nanchang, a 73-year-old woman suffering from H10N8 avian influenza on December 6th death due to respiratory failure and shock. This is the first detection of human infection H10N8 of deaths. 

The clinical diagnosis of patients with severe pneumonia, accompanied by high blood pressure, and heart disease myasthenia gravis and other infrastructure, low levels of immunity. It is learned that the deceased had live poultry business market exposure history. Patients on November 30 in a hospital for treatment of income Nanchang, December 6 due to respiratory failure, shock and death. All close contacts exception does not appear.

Director of the China Disease Prevention and Control Center emergency center, said Feng Zijian, currently H10N8 source of infection can not be fully determined. Deceased live bird markets exposure history only as a clue.   

In recent years, China's health sector increased ILI cases of pneumonia of unknown causes and monitoring efforts, monitoring has improved sensitivity, has monitored discovered H1, H3, H5, H7 and other influenza viruses , influenza and other respiratory diseases and to strengthen prevention and control work. 

Feng Zijian noted that animal influenza virus infection in humans phenomenon had occurred many times, this monitoring to disease surveillance H10N8 such a sporadic cases and improve our nation's laboratory capacity and have a great relationship. There will also be before, but found none. Strictly speaking, this should be the first humans "detected" the virus.

I posted about this case on December 17 and on a second H10N8 fatality on February 13.

CIDRAP: Two new H7N9 cases as experts suggest H9N2 control

Via CIDRAP, a report by Lisa Schnirring: Two new H7N9 cases as experts suggest H9N2 control. Click through for the full report and many links. Excerpt:

Two more H7N9 influenza cases were reported in China today, including the first one from Zhejiang province in 2 weeks, as health groups weighed in with risk assessment updates and experts from China suggested a new way to get a jump on H7N9 and other novel viruses. 

The newly confirmed infection from Zhejiang province, which last reported a case on Feb 12, involves a 2-year-old girl who is hospitalized with a mild illness, according to a provincial health department statement translated and posted by FluTrackers, an infectious disease news message board. Zhejiang province has the most H7N9 cases of any in China and has played a pivotal role in both outbreak waves. 

The other new case involves a 65-year-old woman from Guangdong province who is hospitalized in critical condition, according to an official statement translated by FluTrackers. 

The new cases lift the two-wave H7N9 outbreak total to 373, with 114 as the unofficial number of deaths. So far 237 illnesses have been detected in the outbreak's second wave, which began in October, compared with 136 in the first wave last spring. 

Risk assessment updates 

In other developments, the European Centre for Disease Prevention and Control (ECDC) and the Public Health Agency of Canada (PHAC) addressed the H7N9 threat in separate risk assessments. 

The ECDC's assessment came in a broader risk assessment of human avian influenza A infection in China, dated Feb 24. The PHAC posted its updated H7N9 risk assessment today. 

The ECDC assessment summarized H7N9 events as of Feb 18, and since then, cases have continued to taper off. However, it said the brisk pace of human infections that marked the second wave might point to a larger wild or domestic bird reservoir, an increase in the number of exposed people, increased transmissibility of the virus, a seasonal pattern, or a combination of factors. 

Meanwhile, the PHAC risk assessment update covers H7N9 developments in China through yesterday. The agency noted that poultry and environmental samples have been found in all areas that reported human cases, except for Jilin province and Beijing. 

The PHAC noted that, in the second wave, cases appear to be less skewed toward older adults, though more infections continue to be detected in males. Seven pediatric cases were reported in January, three of which involved mild illnesses, and so far no unusual clinical presentations have been reported, the agency said.

So far, the virus doesn't spread easily among people, though limited person-to-person transmission may occur when there is close contact, the update noted. The H7N9 virus bears close watching, though, because less severe cases have been seen in influenza-like illness surveillance, and the PHAC said it expects more cases to be reported as the flu season progresses.

Pandemic potential of emerging influenza

Via The Lancet, an editorial: Pandemic potential of emerging influenza. It makes a factual error in the first sentence (the Canadian H5N1 case was a woman, not a man), but this is a thoughtful commentary. Excerpt:

In January this year, the first case of highly pathogenic avian influenza H5N1 was detected in the Americas when a Canadian man returning from Beijing fell ill and subsequently died. January also saw a sharp upturn in the number of cases of H7N9 avian influenza in China with 169 cases detected in 1 month, compared with 144 up to the end of last year since it was first identified in March 2013. 

Another familiar virus, 2009 pandemic influenza A H1N1 has also been hitting the headlines in Egypt, where there have been over 300 cases and around 38 deaths since December, and in Mexico over 400 deaths have been associated with H1N1 this year. 

Moreover, researchers have recently reported the first case of human disease caused by an H10N8 strain, which killed a 73-year-old woman in China in December last year. 

Each new and emerging strain detected in association with severe disease or rapid global spread brings speculation of the next pandemic, the spectre of the 1918 influenza pandemic looming large in the consciousness of health professionals, virologists, and the public. 

Anticipation of a new pandemic is added a sense of mystery by the mercurial nature of influenza viruses, which undergo continuous antigenic evolution as they pass through human populations, retreat into animal reservoirs, reassort with other viruses, and re-emerge. 

With changes in surveillance and technology the detection and identification of new influenza strains causing human disease is easier than ever—the challenge now is how to judge the risk posed by each virus.

ECDC: Rapid Risk Assessment of avian flu viruses in China

ECDC has published Human infections with avian influenza A viruses in China, new ECDC Rapid Risk Assessment. Click through to download the full document as a PDF. Excerpt from the summary:

In its new Rapid Risk Assessment, ECDC summarises the latest information about human infections with avian influenza A viruses in China. It focuses on A(H7N9) and A(H5N1) and includes other avian influenza A viruses recently identified. It assesses the risk to public health in the EU/EEA countries and to EU/EEA citizens. 

The severe nature of human infections and the persistence of avian influenzas A(H7N9) and A(H5N1) in poultry represents a significant long-term threat to humans, either through zoonotic transmission or potentially through developing pandemic capacity. However, the most likely current scenario for China is that these outbreaks remain zoonotic outbreaks in which the virus is transmitted sporadically to humans in close contact with the animal reservoir, similar to the influenza A(H5N1) situation.   

The recent importation of A(H5N1) from China to Canada and A(H7N9) from China to Malaysia in travellers highlights the possibility of travel-related cases being detected also in Europe. This should be prepared for by the EU Member States. However, sporadic cases imported from China would not alter ECDC’s current risk assessment.   

The A(H7N9) transmission pattern and the continued and increasing transmission of this novel reassortant avian influenza virus capable of causing severe disease in humans remains a cause for concern due to its pandemic potential. While likely human-to-human transmission of A(H7N9) and A(H5N1) in clusters of reported cases has been documented in a few instances, there is no indication of sustained human-to-human transmission. 

The detection of other new avian influenza human cases, namely A(H10N8) and A(H6N1) likely reflects enhanced surveillance activities in China and Taiwan.   

At present, the most immediate threat to EU citizens is to those living in China or visiting the country. It is advised to avoid live-bird markets and contact with live poultry in China.

ECDC: CDTR report, week 8

ECDC has published Monitoring current threats: ECDC Communicable Disease Threats Report (CDTR), week 8/2014. Click through to download the PDF. The summary:

The ECDC Communicable Disease Threats Report is a weekly bulletin intended for epidemiologists and health professionals in the area of communicable disease prevention and control. This issue covers the period 16 to 22 February 2014 and includes updates on: 

Seasonal influenza: 

Sixteen of the 29 reporting countries reported widespread geographic patterns of influenza activity, however only two reported high intensity activity. 

Measles: 

Anthroposophic schools were involved in two recent measles outbreaks in two countries in 2014: in Austria and Finland. New outbreaks have been reported in Wales in the UK since October 2013 in the same area affected last year. The UK has also seen ten measles cases in returning travellers from the Philippines where there is an ongoing outbreak. The measles outbreak in the Netherlands is still ongoing but is showing signs of slowing down. The CDTR reports on measles in Europe once a month. 

Avian influenza A(H10N8) in China: 

As of 13 February 2014, three human cases of avian influenza A(H10N8) virus have been reported in Jiangxi province in China, the first case was reported by the Chinese authorities on 17 December 2012. These cases are considered to be sporadic cases that occurred in the context of enhanced testing of avian influenza in China. There is no evidence of secondary transmission. 

Chikungunya in the Caribbean: 

In the past week, 293 new cases of chikungunya have been reported in the Caribbean. New confirmed cases were reported from Saint Martin (FR), Martinique, Saint Barthélemy, Guadeloupe. In addition new cases were reported from Dominica. French Guyana reported two autochthonous cases. These last two cases are the first autochthonous chikungunya cases in mainland South America. St. Kitts and Nevis reported the first confirmed case.

H10N8: A virus on the verge?

Via The Lancet: Avian influenza A H10N8—a virus on the verge? The conclusion:

Does H10N8 pose a pandemic threat? The introduction of a new influenza A subtype into people is always a public health concern. However, pandemic viruses are characterised by high transmission. Sustained person-to-person transmission has not been reported with influenza A virus subtypes other than H1, H2, and H3 viruses, and so far H10 viruses are no exception. JX346 did not successfully spread to close contacts,3 and mild cases of H10N7 virus infection in Australia and Egypt did not transfer to exposed relatives.1 

Experiments done to improve understanding of what is necessary for sustained transmission of avian H5N1 influenza A viruses in ferrets in laboratory settings10, 11 showed several mutations throughout the viral genome (mainly in haemagglutinin and the polymerase complex) that are needed for this adaptation. Of those, JX346 shows PB1 polymorphisms at positions 99 and 368, which are associated with enhanced replication and transmissibility in ferrets, and the well characterised mammalian adaptation PB2 627KLys. 

However, despite more than 15 years of H5N1 transmission events from birds to people, none of these mutations resulted in a strain that could be transmitted between people.12 

How virulent is the H10N8 virus? Although H10N8 is predicted to have low pathogenicity in poultry and other avian species, it is too early to say anything conclusive about its virulence in people because of the small number of cases. Even for avian influenza A H5N1 and H7N9 viruses, the real frequency of mild and asymptomatic infections is unknown, despite the many deaths associated with human infections, because diagnosis and detection is generally done only when patients are admitted to hospital, and therefore is biased towards severe cases. 

While increased surveillance might also be responsible for the increase in number of human infections with avian viruses, most human infections are associated with avian viruses containing the H9N2 internal gene cassette, on the basis of available sequences.13, 14 Studies are needed to understand how this internal cassette helps avian influenza viruses seemingly well adapted to poultry to also jump more frequently into people and cause disease. 

More human cases of avian influenza A H7N9 virus infection have been reported in China in the past year than with H5N1 viruses since their emergence in 1997.13, 14 Both reopening of live poultry markets and seasonality might have contributed to an apparent re-emergence of H7N9 human infections in the past month. Whether cases of avian influenza A H10N8 virus infection are going to increase is unknown, because how widely these viruses are circulating in poultry is unknown. 

More surveillance will be needed to establish the origin of H10N8 and to monitor potential future transmission events. Additionally, other new avian influenza virus subtypes, reassorting with H9N2 viruses, might emerge in the near future and cause human infections.

ProMED-mail on H10N8

ProMED-mail has a Xinhua report on yesterday's fatal H10N8 case. The moderator then adds some observations:

This is the 3rd case of human infection with another new species-jumping avian influenza virus, influenza A H10N8. All 3 occurred in adults but the direct exposure to birds in this case is unclear as well as whether there were additional co-morbidities in the patient; 2 of the 3 have died and the 3rd case was reported to have been in serious condition and may well have died as well. 

Whether this strain of avian influenza will be the "next big thing" is too early to say. For pandemic influenza to occur, the strain must be new to man without a vaccine available (true for H10N8), cause significant disease in people (true for H10N8), and, finally, be able to cause prolonged person-to-person spread which has not occurred for H10N8, H7N9, or H5N1. Like the Meatloaf song, "Two out of Three ain't bad." Indeed, 2 out of 3, for epidemic potential is good (for humans)! 

When the next pandemic strain of influenza A will emerge remains uncertain, but the pandemic influenza clock is ticking; we just do not know what time it is.

China: Another fatal H10N8 case

Via Xinhua: China reports another H10N8 case.

Health authorities in east China's Jiangxi Province confirmed on Thursday another human case of H10N8, a new strain of bird flu. 

The patient, a 75-year-old man in Nanchang, capital of Jiangxi, developed symptoms and was admitted to hospital on Feb. 4. The patient died on Feb. 8, the provincial health and family planning department announced. 

Health experts called on the public to stay away from live poultry and to have good hygiene habits. 

On Dec. 17, local health authorities in Jiangxi confirmed the first human infection of H10N8, when a 73-year-old woman died from the virus. Health experts then said H10N8 was known among birds, but human infection had never been reported before.