Wednesday 20 May 2009

Influenza Gateway by BioMed Central


Cases of the influenza A(H1N1) virus, known commonly as swine flu, continue to be recorded on a daily basis to the understandable unease of the general population. Whilst the media hype slowly dies down, BioMed Central continues to publish research investigating the H1N1 virus and has now compiled a collection of recently published research articles, commentaries, reviews and editorials relating to H1N1.

http://www.biomedcentral.com/gateways/influenza

Thursday 7 May 2009

HealthMap

Global Disease Map

http://healthmap.org/swineflu

By Clark Freifeld and John Brownstein.

Predicting the future

There is an on going debate about the future of the current pandemic. This debate is portrayed superbly in the following articles by the BBC. The first was published on May the 1st and the second only five days later. It is important to understand that scientific knowledge cannot predict the evolution of the virus; this is why the global scientific community is monitoring the progress of the pandemic in such an intense manner.
What scientists know about swine flu

Emma Wilkinson Health reporter, BBC News 13:17 GMT, Friday, 1 May 2009 14:17 UK

Preliminary analysis of the swine flu virus suggests it is a fairly mild strain, scientists say.

It is believed that a further mutation would be needed in order for the H1N1 virus to cause the mass deaths that have been estimated by some.

But at this point, it is impossible to predict with any accuracy how the virus will continue to evolve.

UK experts at the National Institute for Medical Research outlined on Friday the work they are due to start on samples of the virus sent from the US.

The research, being done at the World Influenza Centre in Mill Hill, will be vital for working out the structure of the virus, where it came from, how quickly it is capable of spreading and its potential to cause illness.

Structure

Analysis done so far suggests what they are dealing with is a mild virus and nowhere near as dangerous as the H5N1 avian flu strain that has caused scientists so much concern over the past decade.

Influenza A viruses are classified according to two proteins on the outer surface of the virus - hemagglutinin (H) and neuraminidase (N).

The swine flu strain is a H1N1 virus, the same type as seasonal flu which circulates throughout the world every year, and kills roughly 0.1% of those infected or higher in an epidemic year.

Professor Wendy Barclay, chair in influenza virology at Imperial College London says initial indications suggest there is nothing about the genetic make-up of the new virus which is a cause for particular concern.

The key to its potential lies largely in the H1 protein.

"There are two aspects - one is which receptors the virus tends to bind to and what we see is that it is binding to the upper respiratory tract rather than deep in the lungs."

When a flu virus binds to the upper respiratory tract, it tends to cause mild illness but can be easily spread as people cough and sneeze, Professor Barclay explains.

If a virus binds further down in the lungs, it tends to cause much more severe illness, as in the case of the H5N1 avian flu virus which has caused concern in recent years.

"With the H1 gene we also look at the cleavage site," she adds.

"The virus has to be cut into two pieces to be active and it uses an enzyme in the host to do that.
"Most influenza viruses are restricted to the respiratory tract because they use enzymes in the lungs.

"But some, like H5 viruses can evolve to cut into two pieces outside the lungs, so they can replicate outside the respiratory tract."

Analysis

These initial indications are largely guesswork from looking at the genetic sequence of the virus and comparing that to what is known from work on other influenza viruses.

It will take weeks and months of biological analysis to properly get a handle on the potential of the H1N1 virus.

The team at Mill Hill, one of four World Health Organisation's centres for influenza research will be working in close collaboration with the Health Protection Agency who are carrying out testing in the UK, and their findings will also feed into the development of a potential vaccine.

Soon, the Wellcome Trust Sanger Institute in Cambridge will begin the genetic sequencing of the virus and will also be monitoring any mutations or changes in how virulent it is.

However, there is one other reassuring aspect about what is known so far.

That is there seems to be nothing unusual as yet in another protein in the centre of the virus, called NS1, which is linked to the strength of the immune response the virus produces.

In some more pathogenic viruses, it is this NS1 protein which initiates a "cytokine storm", a particularly severe immune reaction that can be fatal in even healthy young people.

Predictions

Scientists have also played down concerns that the milder H1N1 virus, could combine with the more dangerous H5N1 avian flu virus, causing a super virus that has the ability to both spread easily between humans and cause severe illness.

This is unlikely - or at least just as unlikely as it ever was and the H5N1 virus has been around for a decade without combining with normal seasonal flu.

Professor Jonathan Ball, an expert in molecular virology at the University of Nottingham said: "The chance of swine H1N1 combining with H5N1 is as likely as any other strain recombining.
"What this outbreak does highlight is how difficult it is to predict new pandemic strains.

"Many people suspected that H5N1 was the most likely candidate for the next pandemic strain, but now it appears that this was a mistake - but that's not to say H5N1 or another reassortment containing parts of H5N1 may not happen in the future.

"That's the trouble - you can't predict."

'Too early' to say flu virus mild

16:55 GMT, Tuesday, 5 May 2009
Sir Liam, who updated the government's weekly cabinet meeting on the flu situation, told BBC News: "We may see an apparent peak in the incidents over the next month or so, but that doesn't mean it's gone away.

"It could be that we'll see a resurgence of the virus in the autumn and winter when the normal flu season starts.

"We must not be complacent. We know that flu viruses can change their character very rapidly as they move through populations."

He added: "These next few months are vitally important in understanding what sort of virus we're dealing with."

The latest case of swine flu, confirmed on Tuesday, was in an adult from the Slough area of Berkshire, the South Central Strategic Health Authority said.

'Quarantine rooms'

The individual, who is associated with travel to Mexico, is responding well to antiviral drugs, the authority added.

It brings the overall totals to 24 in England and four in Scotland. (5/5)

Meanwhile Department of Health leaflets, stressing the importance of good hygiene, are being delivered across the UK.

A spokesman said: "It is right that we are preparing for the possibility of a global pandemic.
"The UK's arrangements are continuing to ensure that we are well-placed to deal with this new infection."

Five UK schools hit by the virus have begun rescheduling GCSEs and A-levels as the summer exam season begins.

Three of the schools are in London, with one in Devon and one in South Gloucestershire. Four are secondary schools.

The latest to be hit by the virus is Alleyn's School in Dulwich, London, where five year-seven pupils were diagnosed on Monday.

A sixth pupil from the independent school, who visited the US during the Easter holidays, was diagnosed with the virus on Sunday.

The school said it was rescheduling A-level exams in art, biology and foreign languages for next week.

In a statement it said: "In line with procedure, the school will be writing to the examination boards who are always sympathetic to students in these circumstances."

Nine out of 10 of the parents had now collected the Tamiflu anti-viral medication offered by the Health Protection Agency, the school added.

More than 1,200 private schools have been given legal advice by the Independent Schools Council, which suggests setting up "quarantine rooms" for pupils suspected of having the virus.
It also says schools should provide a policy on what to do in case of a pandemic.

Governors at Dolphin School in Battersea, London, closed its doors as a precaution after it emerged that two pupils - siblings of pupils at Alleyn's - had been confirmed with the virus.

Swine flu has already closed South Hampstead High School in north west London, Downend in South Gloucestershire and Paignton Community and Sports College in Devon.

Around 300 other people in the UK are currently awaiting the results of tests to determine whether they have the virus.

WHO says H1N1 pigs must be kept out of food supply

Wed May 6, 2009 4:16pm EDT
  • WHO expert says flu viruses can survive freezing
  • Blood of H1N1 infected pigs may also contain virus
  • Meat from sick pigs or pigs found dead must not be eaten
  • Existing food safety, trade checks offer ample protection (Recasts with more comments on food safety standards)
By Tan Ee Lyn
HONG KONG, May 6 (Reuters)
Meat from pigs infected with H1N1 flu should not be eaten by humans, a WHO official said on Wednesday, while stressing that existing checks were sufficient to safeguard the food supply from the new virus strain.Jorgen Schlundt, director of the World Health Organisation's Department of Food Safety, Zoonoses and Foodborne Diseases, said care must be taken to ensure that pigs and their meat were checked for all diseases, including the H1N1 virus that may be present in the blood of infected animals."Meat from sick pigs or pigs found dead should not be processed or used for human consumption under any circumstances," he told Reuters.
It is possible for flu viruses such as the new H1N1 strain to survive the freezing process and be present in thawed meat, as well as in blood, the expert said. But he stressed that there was no risk of infection from eating or handling pork so long as normal precautions were adhered to."While it is possible for influenza viruses to survive the freezing process and be present on thawed meat, there are no data available on the survival of Influenza A/H1N1 on meat nor any data on the infectious dose for people," he wrote in an email reply to questions from Reuters about risks from the respiratory secretions and blood of infected pigs.
Schlundt said it was still unclear whether and how long the virus, which is commonly known as swine flu but also contains human and avian flu pieces, would be present in the blood and meat-juices of animals which contracted it."The likelihood of influenza viruses to be in the blood of an infected animal depends on the specific virus. Blood (and meat-juice) from influenza H1N1-infected pigs may potentially contain virus, but at present, this has not been established," he said.
The WHO has urged veterinarians, farm hands and slaughterhouse workers to exercise caution in their contact with pigs to avoid contamination until more is known about how it manifests in the animals."In general, we recommend that persons involved in activities where they could come in contact with large amounts of blood and secretions, such as those slaughtering/eviscerating pigs, wear appropriate protective equipment," Schlundt said.The Food and Agriculture Organisation (FAO) and World Organisation for Animal Health (OIE) have said import bans on pigs and pork are not required to safeguard public health because the disease is not food-borne and does not pose a threat in dead animal tissue.
BASIC GUIDANCE
While acknowledging technical questions remain about the conditions in which the virus may be present, Schlundt stressed that the WHO had not changed its basic guidance that pork is safe to eat.International trade and food safety guidelines -- drawn up well before the latest flu scare -- provide ample protection and ensure meat is not sourced from sick animals, he said."Sick animals should not enter the food chain. If you are following existing guidelines it (the virus) will not get into the human food chain," he said.
The Paris-based OIE has also said the new flu strain does not require supplemental care or checks besides those in place for other diseases, and stressed live pigs can continue to be traded using normal health inspection standards.The new H1N1 swine flu virus is being transmitted from person to person, not from pigs to people.Its global spread has prompted many countries to limit pork imports, however. As many as 20 governments have imposed import bans on live pigs and meat from affected countries to prevent exposure to the virus.Such fears increased after Canadian authorities said on Saturday a herd of swine was infected by a farmer who had returned from Mexico.
The WHO said its laboratories have confirmed more than 1,500 cases of the flu virus in 22 countries.While the strain is mainly spread from person to person through coughing and sneezing, experts do not know for sure how this virus came to be, which animal passed it to the first human patient and when that occurred.But the case of the farmer infecting the pigs in Canada fuelled fears of the virus yet again jumping the species barrier -- this time from pig to human -- and possibly becoming more virulent in the process.

(Additional reporting by Laura Macinnis in Geneva; Editing by Alison Williams)

http://www.reuters.com/article/swineFlu/idUSL6299708?feedType=RSS&feedName=swineFlu&virtualBrandChannel=10521

Tuesday 5 May 2009

What happens if swine flu goes away?

Tue May 5, 2009 2:45am EDT

WASHINGTON (Reuters) - With Mexico saying the worst may be over and the new H1N1 virus starting to look more like a seasonal flu strain in the United States and elsewhere, critics are going to start asking if public health officials overreacted to the outbreak.

Since the new swine flu virus was first identified two weeks ago in two children in Texas and California, the World Health Organization pushed its pandemic alert level from a three to a five, meaning a pandemic is imminent.

Mexico closed schools, stopped public events and took a big hit to tourism. The U.S. government mobilized 25 percent of its stockpile of antiviral drugs and started work on a vaccine against the new strain.

But the death toll is being rolled back as Mexican officials realize it will be impossible to know if long-buried or cremated victims died of H1N1 swine flu. And while the infection is spreading rapidly across the United States, it appears to be no worse than seasonal flu.

Scientists who study flu say the coordinated, global response was appropriate.

"If it doesn't become more virulent, first of all, many people will heave a great sigh of relief," said Dr. Scott Lillibridge, who helped set up the Center for Disease Control and Prevention's Bioterrorism Preparedness and Response Program and who is now at the University of Texas Health Sciences Center in Houston.

But Lillibridge echoes what the WHO and CDC have been saying: viruses mutate and change all the time and it is too early to say how bad this virus really is.

"We are only a few days into a major international mobilization for an outbreak that could continue months into the future," Lillibridge said in a telephone interview.

The U.S. government has been preparing for this scenario for years.

One of the messages that has come up repeatedly is that the 1918 pandemic, cited as the worst-case scenario because it killed upwards of 40 million people, started with a mild arrival of a new virus, now identified as H1N1, in the spring.

It disappeared over the summer, but roared back with a vengeance in August.

REPEATING HISTORY

"Will there be later disease, and if so, will it be more severe?" CDC acting director Dr. Richard Besser asked on Monday.

"There is no doubt in my mind that CDC, the Department of Homeland Security, and the Health and Human Services Department will use the lull to get ready," said risk communications consultant Peter Sandman, who has taken a special interest in pandemic flu.

"They will stay focused on this problem. They will continue to get ready for a possible pandemic in the fall.".....

Influenza A(H1N1) - update 14 by the WORLD HEALTH ORGANIZATION


4 May 2009


As of 18:00 GMT, 4 May 2009


21 countries have officially reported 1085 cases of influenza A (H1N1) infection.


Mexico has reported 590 laboratory confirmed human cases of infection, including 25 deaths. The United States has reported 286 laboratory confirmed human cases, including one death.


The following countries have reported laboratory confirmed cases with no deaths - Austria (1), Canada (101), China, Hong Kong Special Administrative Region (1), Costa Rica (1), Colombia (1), Denmark (1), El Salvador (2), France (4), Germany (8), Ireland (1), Israel (4), Italy (2), Netherlands (1), New Zealand (6), Portugal (1), Republic of Korea (1), Spain (54), Switzerland (1) and the United Kingdom (18).


It is considered prudent for people who are ill to delay international travel and for people developing symptoms following international travel to seek medical attention, in line with guidance from national authorities. Individuals are advised to wash hands thoroughly with soap and water on a regular basis and should seek medical attention if they develop any symptoms of influenza-like illness.


WHO advises no restriction of regular travel or closure of borders.


There is no risk of infection from this virus from consumption of well-cooked pork and pork products.


Further information on the situation will be available on the WHO website on a regular basis.




Monday 4 May 2009

Influenza A(H1N1) - update 13 by the WORLD HEALTH ORGANIZATION

4 May 2009 of 06:00 GMT
20 countries have officially reported 985 cases of influenza A (H1N1) infection.

Mexico has reported 590 laboratory confirmed human cases of infection, including 25 deaths. The higher number of cases from Mexico reflects ongoing testing of previously collected specimens. The United States has reported 226 laboratory confirmed human cases, including one death.

The following countries have reported laboratory confirmed cases with no deaths - Austria (1), Canada (85), China, Hong Kong Special Administrative Region (1), Costa Rica (1), Colombia (1), Denmark (1), El Salvador (2), France (2), Germany (8), Ireland (1), Israel (3), Italy (1), Netherlands (1), New Zealand (4), Republic of Korea (1), Spain (40), Switzerland (1) and the United Kingdom (15).

There is no risk of infection from this virus from consumption of well-cooked pork and pork products.

It is considered prudent for people who are ill to delay international travel and for people developing symptoms following international travel to seek medical attention, in line with guidance from national authorities. Individuals are advised to wash hands thoroughly with soap and water on a regular basis and should seek medical attention if they develop any symptoms of influenza-like illness.

WHO advises no restriction of regular travel or closure of borders.

Further information on the situation will be available on the WHO website on a regular basis.

Opinions – Suggestions - Remarks