Unlike SARS, avian flu or ebola, swine flu has gone truly global. Confronted by the 21st century’s first pandemic, how scared should we be?
 | Invisible ThreatAn airport thermal camera monits passengers arriving from abroad at Sofia airport in Bulgaria. The first case of swine flu in Bulgaria was a passenger from the United States (Photo: Reuters) |
Swine flu parties are all the rage in the United Kingdom. Parents seek out the infected, so children catch the H1N1 virus and build up immunity before a really nasty strain of the flu bug arrives in winter.
Whether real or media inventions, swine flu partygoers reflect what we know about influenza viruses: beware the next flu season because it could be worse than the last.
The 1918 Spanish influenza pandemic was the most devastating outbreak of infectious disease in human history, accounting for about 50 million deaths worldwide.
But the first outbreak of Spanish flu—a variant of avian flu—was relatively mild, explains Jacques Jeugmans, an expert on avian flu at the Asia Development Bank. After disappearing in the summer, Spanish flu returned with a vengeance.
“It is impossible to say whether the virus changed, but we know that Spanish flu was not that serious in the spring and more serious in the fall,” says Jeugmans, who notes similarities between Spanish flu and swine flu. “Swine flu seems to attack people between 20 and 39 which is also characteristic of Spanish flu. This worries the public health community.”
Life Cycle of a Virus
Pandemics spread like waves or tides. They peak then trough, advance then withdraw. Medics, governments, and the media trail in their wake. The most important factor for influenza is the seasons. Flu thrives in winter and dislikes summer.
And so, in July 2009, northern hemisphere countries are keenly watching the winter flu season in South America, Australia and southern Africa, trying to figure out swine flu’s next move.
All flu viruses change slightly from one season to the next. Some people catch flu and develop immunity to the virus. Others take vaccines to protect against infection. Surveillance of the virus enables regular update of vaccines to keep pace with mutations.
But every 30 or 40 years there is a big change that catches everyone unawares. When that happens no one has immunity against the infection because it is a completely new virus. If this new virus can spread between people, a pandemic occurs.
This happened with Spanish flu and so it seems with the H1N1 virus, a never-before-seen mixture of swine, human and avian flu viruses first identified in Mexico and the U.S. in April 2009.
Declared a global pandemic by the World Health Organization two months later, H1N1 had by then infected a confirmed 67,000 people in 114 countries, killing 300.
Don’t Panic!
Pandemic normally spells panic as people confuse the spread of a disease with its severity. But unlike SARS or avian flu most people infected with H1N1 suffer mild symptoms. The death rate is low and those who die almost always have underlying chronic conditions such as respiratory illness, cardiovascular disease or diabetes.
The World Health Organization, under pressure from some governments, consequently postponed declaring a pandemic, fearing the negative effects on public confidence. After initial attempts to isolate the disease, most governments decided the risks to health were not severe enough to warrant the effort. Instead they concentrated on telling the public to be vigilant about their own health and hygiene.
The virus kept spreading, however, prompting the WHO’s declaration of a level 6 pandemic, meaning pharmaceutical companies would start developing and manufacturing vaccines against H1N1, switching production from seasonal flu vaccines.
Some say the WHO’s decision is a gamble, because there is not enough capacity to manufacture vaccines for both seasonal flu and pandemic flu at the same time. Is it right, they ask, to divert resources from seasonal flu, which kills hundreds of thousands every year?
Others argue better safe than sorry. Because swine flu is a radical new variant of influenza nobody has built up immunity and so it could spread uncontrollably, putting intolerable strain on health services. Some Argentine hospitals were already clogged with swine flu victims by late June 2009.
Health authorities must make a choice. And if there is not enough vaccine to go around, swine flu parties might be a genuine option.
“Scientifically, if you get infected now and get a mild flu you will probably be partly immunized,” says Jeugmans. “But from a public health point of view I am completely against parties. If everyone gets sick at the same time you will have big problems in hospitals.”
Mutant genes
The biggest concern is that H1N1 could mutate into something much nastier. Influenza viruses not only mutate quickly and unpredictably, but they can swap genes, especially if a person or animal becomes infected with two strains at once.
This worries Indonesian Health Minister Siti Fadillah Supari, who has said she is concerned about H1N1 "marrying" with H5N1 avian flu. "We are scared because we are the warehouse of the world's most virulent H5N1," Supari said.
Although it only rarely infects people, avian flu has killed 262 out of 433 infected globally since 2003, with 141 of those cases in Indonesia. The worst-case scenario would be someone catching both viruses and developing and spreading a combination of H1N1’s infectiousness and H5N1’s severity.
The WHO Director-General Dr. Margaret Chan said in June 2009 that the virus was still “very stable” but also acknowledged that influenza virus is “highly unpredictable and has great potential for mutation.” Although we have never been so well prepared for or better protected against pandemics, nobody really knows what the next flu season will bring.
editor: James Tulloch
publishing date: July 1, 2009
Do you have something interesting to add? Write a comment and discuss this topic with other readers. Comments should be on-topic, non-commercial, and not contain abuse of any kind.
Comment Policy
Antibiotic
H1N1 virus is very dangerous for human being and its antibiotic may be more costly and unavailable. But how many days it will be available?