H5N1

China: Hunan reports one human H9N2 AIV case in Changsha

Via Flu in China, a report from the Government Information Bureau of Macau SAR: China: Hunan reported one human H9N2 AIV case in Changsha.

According to the BOH of Macau S.A.R., the authority of mainland notified BOH that one human H9N2 AIV case reported in Hunan province, the 20 month old female, lived in Changsha city of Hunan province, now in mild condition, had visited the local live poultry market prior to the onset of symptoms on 27th Nov.

China: H7N9, H9N2 cases reported in Beijing

Via Flu in China: China: Beijing human AIV (H7N9,H9N2) cases report.

According to the Beijing CDC, Beijing has reported total of 19 human H7N9 AIV cases since 2017. 11 of them were local cases(57.9%), 8 of them were imported cases (42.1%). All 11 local cases reported in the second quarter of 2017, includes 9 cases in April and 2 cases in May (37-year-old female and 60-year-old female), all local patients were residents of rural area. 

Recently, Beijing also reported a human H9N2 AIV case, the 32-year-old male, outdoor worker, had symptoms such as fever, cough, sore throat, stuffy and running nose, chills, fatigue, headache, muscular soreness. He is now fully recovered.

China: First documented case of avian influenza (H5N1) virus infection in a lion

Via Emerging Microbes & Infections: First documented case of avian influenza (H5N1) virus infection in a lion. The conclusion:

In summary, we documented the first infection of a lion with a highly pathogenic H5N1 AIV, expanding the host range of AIV. This virus was a reassortant from circulating H5N1/H9N2 viruses and remained prevalent among poultry. Since this virus was highly virulent to the lion and that AIV has been reported to cause deaths in tigers and leopards, we believe that captive animals are under certain risk of AIV infections, and increased surveillance is needed to track and chart the ongoing evolution of circulating AIV with respect to their potential to infect susceptible mammalian hosts.

Eurosurveillance: Isolation of H5N6, H7N9, H9N2 from air at live poultry markets in China

Via Eurosurveillance: Isolation of H5N6, H7N9 and H9N2 avian influenza A viruses from air sampled at live poultry markets in China, 2014 and 2015. The abstract:

Zoonotic infections by avian influenza viruses occur at the human–poultry interface, but the modes of transmission have not been fully investigated. 

We assessed the potential for airborne and fomite transmission at live poultry markets in Guangzhou city and in Hong Kong Special Administrative Region (SAR), China, during 2014 and 2015. Viral genome and infectious avian influenza A viruses of H5N6, H7N9, and H9N2 subtypes were detected predominantly from particles larger or equal to 1 μm in diameter in the air sampled with cyclone-based bioaerosol samplers at the live poultry markets in Guangzhou. 

Influenza A(H9N2) viruses were ubiquitously isolated every month during the study period from air and environmental swabs, and different lineages of H9N2 virus were isolated from markets where chickens and minor land-based poultry were sold. 

The use of de-feathering devices increased the quantity of virus-laden airborne particles while market closure reduced the amount of such particles. The results highlight the possibility of airborne transmission of avian influenza viruses among poultry or from poultry to humans within such settings. 

This may explain epidemiological observations in which some patients with H7N9 infection reported being in markets but no direct contact with live poultry or poultry stalls.

CIDRAP news scan for May 23: Avian flu cases; pistachio Salmonella outbreak; flu antigenic mutations

Via CIDRAP: News Scan for May 23, 2016 | Avian flu cases; Pistachio Salmonella outbreak; Flu antigenic mutations. Excerpt:

Chinese officials reported another human case of H7N9 avian influenza, the second such infection in Hebei province in nearly 3 years, according to a post yesterday on Avian Flu Diary (AFD). Elsewhere, Egypt documented an H9 case in a toddler, according to a May 19 World Health Organization (WHO) report. 

The H7N9 case in China involved a 57-year-old man from Xinji city in Hebei. He experienced onset of headache and fever on May 10 and was hospitalized in Hengshui city on May 16, where he remains in serious condition. The patient is a farmer, and his close contacts are being monitored for signs of illness, AFD said. 

The infection is only the second H7N9 case in Hebei province since the virus emerged in China 4 years ago. Hebei's last H7N9 case occurred in July 2013, AFD said. 

The new case lifts the global H7N9 total to 789, according to a list maintained by FluTrackers, an infectious disease message board. 

Elsewhere, the WHO reported an H9 infection in an 18-month-old boy from Cairo governorate who was exposed to live poultry at a market. The boy developed symptoms on Apr 10 and is in good condition. Though this is not confirmed, his infection is likely due to H9N2, which causes mild illness, the WHO said. 

Globally, 28 cases of H9N2 have been reported, and the virus shows no evidence of human-to-human transmission, the WHO said.

Hong Kong: HKU breakthrough in fight against bird flu

When University of Hong Kong experts say something looks good, I believe them. Via The Standard, a March 17 report: HKU breakthrough in fight against bird flu.

University of Hong Kong scientists hope an experimental drug used for acute respiratory distress syndrome could better treat the dreaded bird flu H5N1 virus. 

The School of Public Health first discovered that H5N1 causes severe pneumonia by impairing proteins called sodium and chloride transporter molecules in the lungs that help draw fluid out of the organs. 

With the discovery of the mechanism of infection, the scientists have begun laboratory testing an experimental treatment for H5N1 using mesenchymal stromal cells. 

The bone marrow-derived stromal cells are already undergoing clinical trials for sepsis and acute respiratory distress syndrome in the United States. 

But no one has tested whether the same cells also could be effective against viral respiratory infections such as flu. 

The treatment strategy could also be used against other bird flu viruses, H7N9 and H9N2, as well as MERS and SARS coronaviruses, said the lead researcher, the school's assistant professor Michael Chan Chi-wai. 

Using laboratory mice, the 14-member team found that H5N1 infection impaired fluid clearance in the lungs' alveoli tiny sacs that allow oxygen and carbon dioxide to move between the lungs and bloodstream more than did seasonal virus. 

The infected cells release "soluble factors" that impair the alveolar sodium and chloride transporters, the team said. 

"Mesenchymal stromal cells prevented or reduced this effect in vitro and in vivo in H5N1-infected mice. These cells provide a potentially effective treatment for acute lung injury in severe influenza," the report concluded. 

Chan said: "We showed that when mice are infected with H5N1, it will inhibit the proteins and the mice developed edemas, lung infection and died. If we treat mice with mesenchymal stromal cells so that activity of sodium and chloride transporter proteins return back to normal, it resolved the edemas."

The study was published in PNAS, but I don't think it's online yet. If you know where the link is, please let me know and I'll update this post.

H5N1 in Egypt: 'Several hundred thousand' cases?

Via Emerging Infectious Diseases: Ahead of Print -Avian Influenza A(H5N1) Virus in Egypt. The abstract:

In Egypt, avian influenza A subtype H5N1 and H9N2 viruses are enzootic in poultry. The control plan devised by veterinary authorities in Egypt to prevent infections in poultry focused mainly on vaccination and ultimately failed. Recently, widespread H5N1 infections in poultry and a substantial increase in the number of human cases of H5N1 infection were observed. 

We summarize surveillance data from 2009 through 2014 and show that avian influenza viruses are established in poultry in Egypt and are continuously evolving genetically and antigenically. We also discuss the epidemiology of human infection with avian influenza in Egypt and describe how the true burden of disease is underestimated. We discuss the failures of relying on vaccinating poultry as the sole intervention tool. 

We conclude by highlighting the key components that need to be included in a new strategy to control avian influenza infections in poultry and humans in Egypt.

The startling conclusion: 

Results from a controlled, serologic cohort study of persons in Egypt exposed and not exposed to poultry estimated the seroprevalence of antibodies against H5N1 (titers >80) at 2%. If this seroprevalence were to be extrapolated to the entire poultry-exposed population in Egypt, the true number of infections would amount to several hundred thousand. These figures are even more striking when it comes to human infection with H9N2 viruses. The seroprevalence of H9N2 antibodies detected in the same cohort study ranged from 5.6% to 7.5%, whereas just 1 case of H9N2 infection was reported.

Novel H5N9 avian flu virus discovered in China

Via The Poultry Site: Novel Avian Flu Virus Discovered in China.

Chinese researchers who analysed influenza viruses from poultry in live-bird markets say they have discovered a novel H5N9 virus, which is a hybrid of various other avian influenza viruses. 

The hybrid received a highly pathogenic H5 gene from the H5N1 avian flu virus and an N9 gene from a human-infecting H7N9 virus, along with other elements. However, the virus only caused low mortality rates when tested on mice. 

The authors took samples in 2013 from seven chickens, a quail, and a duck at two live-bird markets in Hangzhou, a city in Zhejiang province, which were linked to outbreaks of human H7N9 cases. The report does not indicate that any of the birds were displaying symptoms of avian flu. 

The team isolated 13 viruses from the samples: 1 H5N1, 2 H5N9, 4 H9N2, and 6 H7N9. 

By sequencing the whole genomes of the two H5N9 isolates, the researchers determined that their hemagglutinin (H) protein matched that of a 2012 H5N1 isolate from Vietnam, while their neuraminidase (N) component derived from a human H7N9 isolate from Hangzhou. 

They also noted that the structure of the H cleavage site is characteristic of highly pathogenic viruses. The six internal genes resembled those of H5N1, H7N9, and H9N2 viruses. 

The pathogenicity of the novel virus in mammals was tested by exposing mice to various doses. Some mice exposed to the highest doses died, but mice receiving lower doses did not suffer from the disease, and the authors concluded that the virus causes low mortality in mice. They also found that the virus didn't spread from infected mice to others placed with them. 

The team determined that the novel H5N9 virus prefers avian-type cell receptors, known as alpha2,3 sialic acid, rather than the human-type receptor, called alpha2,6. They said this may explain why the virus caused low mortality in mice. 

The report says a highly pathogenic H5N9 virus was found in turkeys in Ontario in 1966, and low-pathogenic H5N9 strains have been found in mallards, northern pintails, and occasionally chickens in the past few decades. But the novel virus is "totally different" from those, the authors concluded. 

"This newly isolated H5N9 virus is a highly pathogenic reassortant virus originating from H5N1, H7N9, and H9N2 subtypes," they wrote. "Live bird markets represent a potential transmission risk to public health and the poultry industry."

The original report is here.

CIDRAP: More avian flu in US birds; Asian H9N2 found in Alaska

Robert Roos at CIDRAP writes: More avian flu in US birds; Asian H9N2 found in Alaska. Excerpt:

The highly pathogenic avian influenza (HPAI) viruses H5N2 and H5N8 are continuing to turn up in US birds, with the latest detections in Montana and California, while an Asian H9N2 virus was found in wild birds in western Alaska, according to recent reports. 

In Montana, the HPAI H5N2 virus was found in a captive gyrfalcon in Columbia Falls in the northwestern part of the state, the Montana Department of Livestock reported in a statement yesterday. The report apparently is the first discovery of the strain in the state. 

The agency said the falcon died of unknown causes and was sent to a state wildlife lab in Bozeman for analysis. The H5N2 finding was later confirmed by a US Department of Agriculture (USDA) lab in Ames, Iowa. 

The bird was owned by a falconer who has about 50 other captive birds, according to a story today in the newspaper The Missoulian. Martin Zaluski, DVM, state veterinarian, said the rest of the birds would be tested for the virus. It appears that the dead falcon was exposed to the disease through contact with a harvested wild duck, he reported. 

The H5N2 virus caused outbreaks in March on several commercial turkey farms in Minnesota, Missouri, and Arkansas, as well as a backyard flock in Kansas. 

H5N8 in wild California ducks 

Meanwhile in California, the HPAI H5N8 virus was found in wild wigeons in two counties, Colusa and Solano, says a report that the USDA filed yesterday with the World Organization for Animal Health (OIE). The report did not specify how many wigeons were infected. Colusa is in the Central Valley northwest of Sacramento, while Solano is in the San Francisco region. 

The H5N8 strain, which originated in Asia, made its first known US appearance in a captive gyrfalcon in Washington state last December. It has since been found in a number of wild birds in California, Oregon, Washington, Idaho, and Nevada, in commercial turkeys and chickens in California, and in backyard poultry in Oregon. 

H9N2 in Alaska 

In other news, researchers with the US Geological Survey reported that they found H9N2 viruses in two wild birds in Alaska that match strains from China and South Korea. 

The viruses were found in testing of samples from 2,924 wild birds at the Izembek National Wildlife Refuge in western Alaska, the researchers reported on Mar 30 in Virology. A fecal sample from an emperor goose and a cloacal sample from a northern pintail duck, both collected in September 2011, yielded the isolates. 

All eight gene segments of the two viruses were more than 99.4% the same as recent H9N2 isolates from Lake Dongting, China, and Cheon-su Bay, South Korea, the researchers wrote.

Will Egypt unleash another flu pandemic?

Via Nature Middle East, the most informative story I've seen so far on the current Egyptian H5N1 outbreak: Will Egypt unleash another flu pandemic? Excerpt:

Hardly a week has passed in 2015 without new cases of human H5N1 influenza infection occuring in Egypt. With at least 46 cases and 13 fatalities in just two months, the number is higher than those reported in the whole of 2014.  

So, what is the status of avian flu in Egypt? 

The story of H5N1 influenza in Egypt dates back to early 2006, when the first human case was detected in Qalyubia governorate shortly after the first outbreak that affected domestic poultry. 

Generally, Influenza viruses are a large group of pathogens that peacefully inhabit the guts of wild migratory waterfowl. These viruses are continuously evolving and occasionally acquire certain genetic changes that enable them to switch hosts and gain a foothold in domestic birds and mammals. Some are endowed with the right key combinations for decoding human cells, causing infections that can vary from isolated and mild disease to devastating pandemics.  

In case of Egypt’s first outbreak, it is believed that this H5N1 virus was a passenger on-board of a wild migratory duck1 visiting Damietta, most likely from Eurasia. Once in Egypt, the newly-arrived H5N1 virus found a hospitable host that allowed it to spread and evolve into a genetically distinct group of “naturalised” viruses. The disease was declared endemic in 2008, and after this recent surge of human cases, Egypt now has the highest number of confirmed human H5N1 cases worldwide.  

Another important subtype, known as H9N2, was reported to co-circulate2 with H5N1 in chickens, with evidence of human exposure3 and a recent case of a boy in Aswan. 

Fortunately, so far, transmission of H5N1 viruses from chickens to humans was very inefficient and no sustained human-to-human transmission has been detected. If these H5N1 viruses becoming human-adapted, and with the current volume of air passengers, an isolated outbreak could turn into a pandemic in no time.  

Pandemics don’t just cause deaths, which we know through modeling studies will be highest in developing countries, but have hefty economic tolls. A recent PNAS study4 has estimated the cost of an influenza pandemic to be somewhere between $374 billion to $7.3 trillion depending on its severity.