New swine influenza viruses in humans

by vrr on 24 April 2009

A new strain of swine influenza virus has been recently isolated from seven persons in the US. Is it time to break out the swine flu vaccine of 1976?

Last week the CDC reported that swine influenza virus had been isolated from two children with respiratory illness in California. The cases were not linked and the children recovered from the illness. The virus was identified as a swine influenza H1N1 strain, similar to viruses that have circulated in American pigs for the past ten years. However some of the viral genes are derived from Eurasian swine influenza viruses. The isolates are new because this particular combination of swine influenza virus RNAs has not been observed before among swine or human viruses.

A similar virus was subsequently identified in five additional individuals in Texas. It’s curious that one of the California children had traveled to Texas before becoming ill, but whether or not the cases are related has not been revealed.

What is the origin of these new swine viruses? None of the people who were infected had known contact with pigs. Others must have acquired the virus from pigs, who then passed it on - demonstrating that the virus can be transmitted among humans.

At the moment these infections don’t seem to be cause for alarm. Because influenza virus surveillance is more intense than ever before, it is likely that new viruses will always be detected. Furthermore, respiratory disease caused by these new viruses has not been very severe. Another mitigating factor is that the influenza season is nearly over - viral transmission wanes when the weather becomes warmer and more humid.

It is believed that swine influenza originated in 1918-19, when pigs became infected with the pandemic influenza virus strain. Since that time, the H1N1 swine virus has been transmitted back to humans. The hypothesis for the origin of swine influenza is supported by the finding that pigs can be experimentally infected with the human 1918 pandemic influenza virus strain. Furthermore, other human influenza virus strains are known to infect pigs. For example, in the early 1970s, a human H3N2 subtype entered the European swine population.

Pigs can be infected with both human and avian influenza virus strains because the cells of their respiratory tract bear receptors for both kinds of viruses. Based on this observation, it has been suggested that influenza viruses pass from birds through pigs on their way to infecting people. For example, if a pig is infected with avian and human influenza A viruses, reassortment of the viral RNAs occurs, leading to new virus strains to which humans are not immune. The 1957 and 1968 human pandemic viruses were reassortants of human and bird strains, although there is no evidence that these viruses arose in pigs. The role of pigs as a ‘mixing vessel’ for influenza virus has been questioned in view of the recent transmission of avian influenza viruses directly to humans.

Swine influenza viruses probably routinely pass among humans and swine; in this case they were detected as a consequence of heightened surveillance. Gerald Ford won’t be rolling over in his grave over this incident.

Weingartl, H., Albrecht, R., Lager, K., Babiuk, S., Marszal, P., Neufeld, J., Embury-Hyatt, C., Lekcharoensuk, P., Tumpey, T., Garcia-Sastre, A., & Richt, J. (2009). Experimental Infection of Pigs with the Human 1918 Pandemic Influenza Virus Journal of Virology, 83 (9), 4287-4296 DOI: 10.1128/JVI.02399-08

de Jong, J., Smith, D., Lapedes, A., Donatelli, I., Campitelli, L., Barigazzi, G., Van Reeth, K., Jones, T., Rimmelzwaan, G., Osterhaus, A., & Fouchier, R. (2007). Antigenic and Genetic Evolution of Swine Influenza A (H3N2) Viruses in Europe Journal of Virology, 81 (8), 4315-4322 DOI: 10.1128/JVI.02458-06

Van Reeth, K. (2007). Avian and swine influenza viruses: our current understanding of the zoonotic risk Veterinary Research, 38 (2), 243-260 DOI: 10.1051/vetres:2006062

Learning From The Influenza Virus' Tricks

Influenza is currently a grave concern for governments and health organisations around the world. The worry is the potential for highly virulent bird flu strains, such as H5N1, to develop the ability to infect humans easily. New drugs and vaccines to halt the spread of the virus are badly needed. Now one of the tactics used by influenza virus to take over the machinery of infected cells has been laid bare by structural biologists at the European Molecular Biology Laboratory (EMBL) and the joint Unit of Virus Host-Cell Interaction of EMBL, the University Joseph Fourier and National Centre for Scientific Research (CNRS), in Grenoble, France. In the current issue of Nature Structural and Molecular Biology they publish a high-resolution image of a key protein domain whose function is to allow the virus to multiply by hijacking the host cell protein production machinery. The findings open the way for the design of new drugs to combat future influenza pandemics.

Upon infection the influenza virus starts multiplying in the cells of its host. One protein that is crucial in this process is the viral polymerase - the enzyme that copies its genetic material and helps to produce more viruses. One component of the polymerase, called PB2, plays a key role in stealing an important tag from host cell RNA molecules to direct the protein production machinery towards the synthesis of viral proteins. Researchers of the groups of Stephen Cusack and Darren Hart at EMBL Grenoble have identified the PB2 domain responsible for binding the tag, produced crystals of it and examined them with the powerful X-ray beams of the European Synchrotron Radiation Facility (ESRF).

"Viruses are masters of cunning when it comes to hijacking the normal functioning of the host cell. The influenza virus steals a password from host messenger RNAs, molecules that carry the instructions for protein production, and uses it to gain access to the cell's protein-making machinery for its own purposes," says Cusack.

The password is a short extra piece of RNA, a modified RNA base called a 'cap', which must be present at the beginning of all messenger RNAs (mRNAs) to direct the cell's protein-synthesis machinery to the starting point. The viral polymerase binds to host cell mRNA via its cap, cuts the cap off and adds it to the beginning of its own mRNA - a process known as 'cap snatching'. The capped viral mRNA can then be recognised by the host cell machinery allowing viral proteins to be made, at the expense of host cell proteins.

The atomic resolution image the EMBL scientists generated of a PB2 domain bound to a cap reveals for the first time the individual amino acids responsible for recognising this special structure. The central interaction is a sandwich with two PB2 amino acids stacking either side of the cap. Whilst this recognition mechanism is similar to other cap-binding proteins, its structural details are distinct. Collaborators at the Centro Nacional de Biotecnologia in Madrid showed that disruption of the PB2 cap-binding site prevents the influenza virus from replicating.

"These findings suggest that the PB2 cap-binding site is a very promising target for anti-influenza drugs," Hart says. "Our new structural insights will help us design mimics of the cap that would inhibit viral replication and hence reduce the spread of virus and the severity of the infection."

Six cases of type A influenza reported in Stone County

February 26, 2008

Six cases of type A influenza reported in Stone County

By Mindy Honey BDN Staff Writer

As of mid-February, the Stone County Health Department had nine cases of influenza-like illnesses and six confirmed cases of Type A Influenza reported, and is urging residents to take precautions to prevent the further spread.
Typically February is the month in which the highest number of influenza cases are reported in Missouri, a release from the health department stated. The Stone County Health Department, in collaboration with the Missouri Department of Health and Senior Services and the Centers for Disease Control and Prevention monitors influenza illness activity throughout Stone County. These agencies work together with health care providers and practitioners to reduce the incidence of influenza-related complications and deaths.
Influenza, commonly known as the “flu,” is a highly contagious viral respiratory illness that affects about 5 to 20 percent of the American population every year. It causes mild to severe illness in most cases; however, in some cases it can be fatal.
Nationwide, more than 200,000 people are hospitalized from flu complications and about 36,000 people die from the flu per year. In Missouri, approximately 1,500 to 3,000 people die yearly, due to influenza and pneumonia.
There are three types of influenza viruses — A, B, and C. Types A and B are subdivided further into certain strains based on their makeup. Influenza C viruses are not sub-typed. Influenza A and B are the viruses that lead to seasonal flu. To confirm or detect the type of influenza virus, a physician must conduct a nasal-pharnagal swab. It takes about 24-72 hours for confirmation of the culture reports.
Influenza is spread from person-to-person through respiratory droplets, usually when an infected person coughs or sneezes on another person. It can also be spread on contaminated objects such as doorknobs, faucets, telephones, grocery cart handles, and light switches.
A person can spread the flu one day before symptoms develop and up to seven days after becoming sick. Children ages six months to five years, pregnant women, people of any age with certain chronic medical conditions, and people 65 years or older are at high risk for complications from the flu.
“Flu-like” symptoms include fever 100 to 102 degrees, headache, tiredness, for up to two to three weeks, cough and chest discomfort which can be severe, runny or stuffy nose, and body aches and pains which can also be severe. Vomiting and diarrhea are not common symptoms of the seasonal flu.
The Stone County Health Department encourages everyone to take the following actions to protect themselves and their family from the flu.
— Get an annual flu vaccination. The Stone County Health Department still has flu vaccinations available for children ages six months to 18 years. Call the Stone County Health Department to make an appointment for your child, at 357-6134 Galena office, or 272-0050 Branson West office.
— Wash your hands often with warm water and soap for 20 seconds. Keep alcohol-based hand sanitizer available when water and soap are not available.
— Cover your cough or sneeze completely. Cough or sneeze into your sleeve or cover your mouth and nose with a tissue and then throw it away.
— Keep your hands away from your eyes, nose and mouth. Germs are spread after touching something that has been contaminated.
— If a person is sick stay home from work, social gatherings, or school/daycare.
— Call your doctor
For more information regarding influenza, contact the Stone County Health Department at (417) 357-6134 or (417) 272-0050.

Source: http://www.bransondailynews.com/story.php?storyID=6591

16/01/2008 Iran reports outbreak

Iran sent immediate notification of an H5N1outbreak  in domestic poultry that began December 12, 2007.

http://www.oie.int/eng/info_ev/en_AI_communications.htm

Oct 25 (Reuters) - A young Indonesian toddler died of bird flu, the World Health Organisation confirmed on its Web site on Thursday. At least 204 people have died of H5N1 since 2003.

Here is a chronology of major recent bird flu developments:



Feb. 8, 2006 - First African cases of the deadly H5N1 strain are detected in poultry in northern Nigeria.

Feb. 18 - India announces its first cases of H5N1, finding the virus in poultry in a western state.

Feb. 25 - France confirms H5N1 at a farm where thousands of turkeys died, the first case of the virus in domestic farm birds in the European Union.

Sept. 28 - China shares long-sought-after samples of H5N1 in what many scientists view as a breakthrough in cooperation.

Feb. 3, 2007 - WHO confirms bird flu killed a 22-year-old Nigerian woman, its first known human fatality in sub-Saharan Africa.

Feb. 27 - Laos confirms its first human case of bird flu. The patient dies on March 7.

April 17 - The first bird flu vaccine for people wins U.S. approval.

May 22 - WHO agrees to demands from developing countries to revamp its system for sharing flu virus samples. It also says it will work to ensure fair distribution of affordable vaccines.

June 16 - Vietnam says bird flu killed a 20-year-old man, the first death in the country from H5N1 since late 2005.

July 26 - India confirms latest outbreak of bird flu in poultry in Manipur state in the remote northeast, is the H5N1 strain. It is the first case reported in India in a year.

Oct 4 - A study by the University of Wisconsin-Madison says that H5N1 has mutated to infect people more easily, although it still has not transformed into a pandemic strain.

Oct 25 - WHO confirms that a young Indonesian toddler from Tangerang, west of the capital Jakarta, died from bird flu. Indonesia has had 110 confirmed cases, of which 89 have been fatal, the highest for any country

وزارت كشاورزی عربستان روز شنبه اعلام كرد كه ‪۱۳هزار و ‪۵۰۰شترمرغ را برای مبارزه با آنفلوانزای پرندگان معدوم كرده است.


به گزارش خبرگزاری فرانسه از ریاض، این وزارت قبلا اعلام كرده بود كه در راستای این برنامه قصد دارد ‪۳/۵میلیون انواع پرنده و ماكیان را معدوم سازد.

آنفلوانزای پرندگان به‌طور عمده یك بیماری خاص طیور محسوب می‌شود اما نخستین مورد ابتلای انسان به این بیماری در سال ‪۱۹۹۷در هنگ كنگ گزارش شد.

Bird Flu In South Korea Is Non-Deadly H7 Strain

Article Date: 26 Nov 2007 - 14:00 PST

The Agriculture Ministry of South Korea confirmed on Saturday 24th November that the latest outbreak of bird flu among farmed ducks was of the non-deadly H7 strain, and not the deadly H5N1 strain that is fatal to humans. There is no evidence that H7 affects humans.

The outbreak occurred in a farm about 200 miles south west of the capital, Seoul. The Korean authorities ordered the slaughter of 17,000 ducks on the farm as a containment measure.

Today, the Japanese Ministry of Agriculture said in a statement relayed by the Associated Press that it was temporarily stopping poultry imports from South Korea because of the outbreak. This is only a few months after lifting an earlier ban on poultry imports from South Korea following a bird flu outbreak last year.

South Korean officials said this most recent outbreak does not affect its status as a bird flu free country, since it is the H7 strain that has caused the latest outbreak and not a return of the H5N1, of which there has been no sign since March this year.

According to the World Health Organization (WHO) information on bird flu outbreaks worldwide, there have been no confirmed cases in South Korea of humans with H5N1 to date. However, the Washington Post on 11th February 2007, relayed a report from South Korean health officials that a farm worker was infected with H5N1 but did not develop symptoms of the disease because of "natural immunity". This was following reports of a sixth outbreak of the deadly virus among farm birds in South Korea in the 12 months preceding that incident, resulting in the slaughter of over 2 million birds.

The deadly H5N1 strain of bird flu can spread to humans if they handle sick or dead birds infected with the disease, and even so it is not easily spread from bird to human. Millions of wild and domestic birds worldwide have been killed or culled as a result of H5N1 outbreaks in recent years.

However, although the current rate of human infection is low, there are two reasons to be concerned about the spread of H5N1. The first is, that even though it does not spread easily to humans, when it does, it is highly dangerous. 206 of the 335 H5N1 worldwide confirmed human cases since 2003 have been fatal, according to the WHO.

The second reason to be concerned about the spread of H5N1 is that many experts now agree that it is only a matter of time before it mutates into a form that does spread easily among humans. And the more opportunities the virus has to infect a large bird population, the more chances it has of mutating into such a form. So containment of H5N1 is important not just for animal health but for human public health too.

But more recently, concern has emerged that it is not just H5N1 that needs to be contained and monitored for reasons of human public as well as animal health.

A recent article by avian flu experts Timm Harder and Ortrud Werner, of the Friedrich-Loeffler-Institute Institute of Diagnostic Virology, Greifswald, Insel Riems, in Germany, writing in the Influenza Report 2006, suggested that even when low pathogenic strains of bird flu, known as LPAI strains, such as H7 and other H5 types, are transmitted from wild birds to susceptible farmed birds such as chickens and turkeys, and have the chance to go through several infection cycles, they can mutate several times over and adapt to their new hosts.

The possibility then arises, wrote Harder and Werner, that not only can the less pathogenic forms of these viruses adapt to their new hosts, but they may have the capability to insert mutations and become strains of a:

"Highly pathogenic form (highly pathogenic avian influenza viruses, HPAIV) inducing overwhelming systemic and rapidly fatal disease. Such HPAI viruses may arise unpredictably de novo in poultry infected with LPAI progenitors of H5 and H7 subtypes."

Telegraph.co.uk

Bird flu causes a goose fat shortage for shops

Last Updated: 3:46am GMT 03/12/2007

Christmas is coming - and there is no goose fat.

Sales of the luxury product doubled last year after millions followed the advice of television chef Nigella Lawson, who hailed goose fat as the crucial ingredient for making the perfect roast potatoes.

However, bird flu has wiped out a third of the goose population across Europe this year, causing a shortage of the fat, and now shops are struggling to find supplies in time for Christmas.

They are suggesting cooks turn to duck fat instead for cooking potatoes and basting the turkey.

Rob Amar, the marketing manager of Buckinghamshire-based fine food suppliers R H Amar, said: "Finding goose fat this year could be a real problem because of the avian flu that has affected flocks throughout Europe.

"Duck fat is a great alternative and will produce an equally tasty Christmas dinner.

"The French use it for all sorts of cooking, including frying and sautéing, and Nigella has recommended duck fat as an alternative to goose fat."

Asda said it had snapped up thousands of tins of duck fat after learning that there could be a shortage of goose fat.

The supermarket says that, like goose fat, duck fat has a high burn point, which makes it just as suitable to cook roast potatoes in a very hot oven.

As an alternative to goose fat, Asda has produced a saffron glaze that is applied to a turkey in the last 15 minutes of cooking, a technique dating back to the 16th century.

CHRONOLOGY-Bird flu developments

Oct 25 (Reuters) - A young Indonesian toddler died of bird flu, the World Health Organisation confirmed on its Web site on Thursday. At least 204 people have died of H5N1 since 2003.

Here is a chronology of major recent bird flu developments:



Feb. 8, 2006 - First African cases of the deadly H5N1 strain are detected in poultry in northern Nigeria.

Feb. 18 - India announces its first cases of H5N1, finding the virus in poultry in a western state.

Feb. 25 - France confirms H5N1 at a farm where thousands of turkeys died, the first case of the virus in domestic farm birds in the European Union.

Sept. 28 - China shares long-sought-after samples of H5N1 in what many scientists view as a breakthrough in cooperation.

Feb. 3, 2007 - WHO confirms bird flu killed a 22-year-old Nigerian woman, its first known human fatality in sub-Saharan Africa.

Feb. 27 - Laos confirms its first human case of bird flu. The patient dies on March 7.

April 17 - The first bird flu vaccine for people wins U.S. approval.

May 22 - WHO agrees to demands from developing countries to revamp its system for sharing flu virus samples. It also says it will work to ensure fair distribution of affordable vaccines.

June 16 - Vietnam says bird flu killed a 20-year-old man, the first death in the country from H5N1 since late 2005.

July 26 - India confirms latest outbreak of bird flu in poultry in Manipur state in the remote northeast, is the H5N1 strain. It is the first case reported in India in a year.

Oct 4 - A study by the University of Wisconsin-Madison says that H5N1 has mutated to infect people more easily, although it still has not transformed into a pandemic strain.

Oct 25 - WHO confirms that a young Indonesian toddler from Tangerang, west of the capital Jakarta, died from bird flu. Indonesia has had 110 confirmed cases, of which 89 have been fatal, the highest for any country.

Oct 25 (Reuters) - A young Indonesian toddler died of bird flu, the World Health Organisation confirmed on its Web site on Thursday. At least 204 people have died of H5N1 since 2003.

Here is a chronology of major recent bird flu developments:



Feb. 8, 2006 - First African cases of the deadly H5N1 strain are detected in poultry in northern Nigeria.

Feb. 18 - India announces its first cases of H5N1, finding the virus in poultry in a western state.

Feb. 25 - France confirms H5N1 at a farm where thousands of turkeys died, the first case of the virus in domestic farm birds in the European Union.

Sept. 28 - China shares long-sought-after samples of H5N1 in what many scientists view as a breakthrough in cooperation.

Feb. 3, 2007 - WHO confirms bird flu killed a 22-year-old Nigerian woman, its first known human fatality in sub-Saharan Africa.

Feb. 27 - Laos confirms its first human case of bird flu. The patient dies on March 7.

April 17 - The first bird flu vaccine for people wins U.S. approval.

May 22 - WHO agrees to demands from developing countries to revamp its system for sharing flu virus samples. It also says it will work to ensure fair distribution of affordable vaccines.

June 16 - Vietnam says bird flu killed a 20-year-old man, the first death in the country from H5N1 since late 2005.

July 26 - India confirms latest outbreak of bird flu in poultry in Manipur state in the remote northeast, is the H5N1 strain. It is the first case reported in India in a year.

Oct 4 - A study by the University of Wisconsin-Madison says that H5N1 has mutated to infect people more easily, although it still has not transformed into a pandemic strain.

Oct 25 - WHO confirms that a young Indonesian toddler from Tangerang, west of the capital Jakarta, died from bird flu. Indonesia has had 110 confirmed cases, of which 89 have been fatal, the highest for any country.

Bird Flu Takes Another Life In Indonesia, Toll Now 88

JAKARTA, Oct 16 (Bernama) -- A 12-year-old boy at Ceger village in Tangerang district in Banten province near here died of the H5N1 virus over the weekend, bringing to 88 the death toll in bird flu cases in Indonesia, a health official reported.

The boy was brought to a local midwife on Oct 3 after suffering from fever for three days, said head of the communicable disease control and prevention section at the Tangerang district health office, Dr Yuliah Iskandar.

As his health condition deteriorated, the boy was transferred to the Tangerang regional hospital where he underwent a medical test on Oct 8, she said, as quoted by Antara news agency Tuesday.

He was later moved to Persahabatan Hospital in Jakarta on Oct 9 for further medical treatment as he had tested positive for bird flu based on the result of a laboratory test conducted by the Health Research and Development Agency and the Eijkmann Institute, she added.

In anticipation of the possible spread of the H5N1 virus in the area, the district health office had sent officers to Ceger village to take samples of the blood of boy's relatives and neighbours.

Dr Yuliah said the boy did not have contact with dead chicken before being infected with the bird flu virus and neither did his parents raise poultry in their backyard.

"But there is backyard poultry about 500 metres from the victim's house," she said.

-- BERNAMA

Japan bans chicken imports from Canada following bird flu outbreak
28 Sep, 2007, 2110 hrs IST, AGENCIES

TOKYO: Japan has banned poultry imports from Canada after a bird flu outbreak in the North American country, the agriculture ministry said Friday.

The suspension takes effect immediately, the ministry said in a statement.

The Canadian Food Inspection Agency said Thursday that a strain of Avian influenza that is not harmful to humans has been confirmed at a large chicken farm in Regina, Saskatchewan.

The ban is expected to have a limited impact on Japanese consumers.

In 2006, Japan imported some 60,000 young chickens and about 2,500 tons of processed eggs from Canada, which accounted for only 10 percent of the Japanese market, the ministry said