# 2784
The Taipei County government began distributing more than 80,000 masks to elementary schools in the county Tuesday to prevent influenza outbreaks, after the county's first case of severe influenza was reported. As of Feb. 6, 11 cases of severe flu had been reported in the county for the year, a sharp increase compared to last year. (CNA)
While we watch the H5N1 virus looking for any critical mutation that could make it easily transmissible - and potentially a pandemic strain - it is important to remember that even seasonal flu strains are constantly mutating and that can occasionally cause a substantial increase in its morbidity and mortality.
Even in a normal influenza season, flu related complications - worldwide - are estimated to claim somewhere between 500,000 and 1 million lives each year.
Viruses, particularly single strand RNA viruses like the influenzas, mutate all the time. They pick up, and discard, genetic bits as they move from host to host, and they make errors in replication.
This happens countless trillions of times every day.
Most of the time, these changes go nowhere. They either have little or no effect on the virus, or they are evolutionary dead-ends, rendering it less capable of replication and transmission.
Small changes in the seasonal virus are normal and are known as antigenic drift. This is why we must reformulate our flu vaccines almost every year.
Antigenic drift can result in unusually severe flu seasons, and occasional vaccine failures. In general, the greater the drift, the greater the impact.
Far less commonly, we see an even bigger change in the seasonal influenza virus. It picks up, or swaps, chunks of genetic material with another virus, and produces a hybrid or a mutation that few people have any immunity to.
This antigenic shift is believed to have caused the last two pandemics, the Hong Kong Flu of 1968 and Asian Flu of 1957.
It is against this constantly changing backdrop that scientists must gauge, six months in advance, how to formulate next season's flu vaccine. Some years, the vaccine turns out to be a good match, and some years it doesn't.
So far, the H1N1 and H3N2 components of this year's vaccine appear to have been a good match here in the United States and in Europe. The `B' component was based on the Victoria line of viruses, and this year, the Yamagata strain is dominate.
The result is this year's vaccine isn't very protective against the `B' strain of influenza.
By now, you are all wondering what this has to do with Taiwan.
Well, over the past few weeks Taiwan's CDC has reported a sharp rise in influenza cases over last year, and disappointing protection from this year's vaccine.
When this happens, we tend to pay attention.
This isn't a crisis, but it is suggestive of a possible drift of the virus.
Flu vaccines not as effective this year as in the past: DOH
Central News Agency
2009-02-03 10:59 PM
Taipei, Feb. 3 (CNA) Influenza vaccines that proved to be effective late last year have failed to live up to expectations early this year, the Department of Health (DOH) said Tuesday.
Chou Jih-haw, deputy director general of DOH's Centers for Disease Control, said more than 3.2 million free flu shots were given to the public in autumn and winter last year.
<snip>
But in January, tests found the vaccines did not work on 70 percent of those with H1N1 viruses and 40 percent of those with the H3N2 virus. A vaccine is considered effective if it controls the virus in 80 percent to 90 percent of those inoculated.
Today the news is reporting that young children are wearing masks in school, and parents are being urged to get their children pneumonia shots.
A Hat Tip to Niman on Flutrackers for this link.
Young people not immune from flu virus: CDC
TAIPEI, Taiwan -- A female nurse aged 30 in Taipei County became the fourth patient killed by flu virus in Taiwan, proving that even the young and able-bodied are not exempt from the mutated virus.
<snip>
The number of severe flu cases reported around Taiwan has increased to 17 since the winter season started, including four confirmed cases, eight suspected cases, and four cases still to be determined.
Among the four patients who died of flu infection, two were aged 30 and 39 respectively, according to the CDC statistics.
The total number of patients visiting hospitals for influenza treatment has reached more 163,000, representing a steep rise of 25 percent from the same period of last year.
CDC officials said the figure did not take into the account of people who purchased over-the-counter drugs at pharmacies.
They said people aged between 20 and 40 should be on heightened alert against the virus.
At the urging of the CDC, local-level county and city governments have stepped up vigilance against the spread of flu virus.
The Taipei County Government distributed more than 86,800 masks to students yesterday as elementary and high schools reopened for a new semester.
Due to the mutation of the flu virus, officials urged parents to take their children aged between two and five to public health stations or hospitals to take vaccine shots against pneumonia.
Influenza viruses are constantly jostling each other for dominance, and as we've seen this year, the results vary by location. In Europe, the H3N2 virus is the dominant strain, while here in the United States, we've seen far more H1N1.
Whether the strain circulating in Taiwan is `fit enough' to become a major player on the world stage is impossible to know right now. It may remain a regional phenomenon, die out completely - or we might just see it on our shores next year or the year after.
For when it comes to influenza viruses, the only thing constant is change.
