San Francisco Sentinel » Blog Archives » THE INEXORABLE MARCH ON SWINE FLU

THE INEXORABLE MARCH ON SWINE FLU

16 June 2009

swine-flu-march-2

Within just a few weeks, the highly infectious H1N1 virus has spread across the globe. For now, symptoms tend to be relatively mild; but health care experts are worried that could change and are preparing for the worst.

Until recently, anyone who traveled to Mexico or the United States was cautioned by friends not to bring home the swine flu. Such warnings are now superfluous.

As of the end of last week, there is officially no longer any country that could offer safety against the new influenza virus. The World Health Organization (WHO) has declared the swine flu a pandemic, raising the global flu alert to the highest level. For the first time in more than 40 years, a completely new flu pathogen is rampant around the world.

Very few people have any natural defenses against the new influenza strain. After being discovered in Mexico in April, the virus has taken turned up in at least 74 countries, from Canada’s polar regions to Tasmania. And this is only the beginning.

The virus is active in prisons and brothels, on cruise ships and in subway stations - and in the heart of Germany. A Japanese school in Düsseldorf was closed last week after at least 46 children contracted the new influenza - one of the schoolchildren had to be taken to the city’s university hospital. Eight children have been infected with the virus in Cologne.

Epidemiologists with Berlin’s Robert Koch Institute (RKI) have launched investigations in both cities, although they no longer hold any hopes of being able to contain the H1N1 virus and keep it from spreading elsewhere in Germany. According to WHO Director-General Margaret Chan, “the virus is now unstoppable.”

The Leap from Species to Species

Scientists now believe that the virus jumped from pigs to humans in January, probably in Mexico. The virus has circulated, unnoticed, among pigs for years, as Andrew Rambaut, of the University of Edinburgh, writes in the journal Science. If pigs in feedlots were checked regularly for new viruses, it might have been possible to prevent the H1N1 virus from making the leap from species to species. Now it’s too late.

By the fall, when the normal seasonal flu wave begins, the virus will likely strike the northern hemisphere with a vengeance. London epidemiologist Neil Ferguson predicts that one in three people will contract the new flu strain within three to four months. So far, the vast majority of cases has not been fatal; the symptoms, which include fever, coughing, a sore throat and often diarrhea, disappear after about five days.

Nevertheless, a full-blown flu pandemic remains one of the more terrifying and unpredictable forces of nature, sweeping across the earth and doing as it pleases. Even in the 21st century, despite all of our knowledge and technology, we are still unable to get the better of a tiny fragment of infectious genetic material.

Millions of people suddenly falling ill and staying home from work could lead to tremendous economic damage or worse. In addition, a pandemic can over-strain the capacity of even the most robust health care systems. Respirators and hospital beds could become scarce, as could doctors, nurses and even ambulance drivers.

Won’t Simply Disappear

Experts estimate that hundreds of thousands, possibly even more, have already been infected with the H1N1 virus. Laboratory tests for the virus have come back positive in about 30,000 cases. So far, only 145 people are known to have died - a lethality rate no higher than the ordinary flu. Although the majority of those who died had other health problems, some did not. WHO has identified an accumulation of severe and deadly cases in pregnant women and healthy people aged between 30 and 50, a conclusion that has many experts worried.

“The severity of the illness caused by this virus could worsen in the future,” warns WHO Assistant Director-General Keiji Fukuda. Flu viruses are notorious for their ability to mutate. There have been many cases in the past when they began as a nuisance but then mutated and turned into killer viruses. It happened in 1918, when the influenza virus killed only a few people at first, but then claimed about 50 million lives, most of them younger people.

Although no physician can predict the progression of the 2009 pandemic, it is clear that it will not simply disappear and will likely be around for a while. Instead, mankind will have to learn to live with the new virus. The pandemic will only subside once a sufficient amount of immunity has spread through the population, either as a result of large-scale vaccinations or people having contracted and survived the infection. Experience has shown that this can take years.
The especially daring - or insane - are taking what they view as preventive action by seeking contacts on the Internet for swine flu infection parties. Their reasoning? Better sick now than dead later.

At this point, H1N1 causes relatively mild symptoms. However, if a more aggressive version of the virus takes hold in a second wave, those now seeking to deliberately contract the virus hope that they will already have developed immunity to it.

Putting Others at Risk

Robert Koch Institute President Jorg Hacker strongly recommends against taking the risk, noting that no one can be completely assured of not become severely ill. Besides, those who deliberately infect themselves are also putting others at risk. Most of all, says Hacker, there is no evidence to support the supposed benefits of early infection. According to Hacker, “it is unclear whether having survived an infection would in fact protect someone against becoming infected again or against a potentially mutated virus.”

In Germany, little has changed as a result of the WHO having raised its pandemic alert to the highest level. The country’s pandemic plans, approved years ago, are already in effect. A crisis team at the Federal Ministry of Health has been meeting regularly for weeks. The states are shoring up their inventories of antiviral drugs. Hospitals and medical practices have been advised to be extremely vigilant. The German Reference Laboratory for Human Influenza in Berlin is studying samples of the virus isolated from those who have already fallen ill to determine whether it is changing its genetic makeup. The authorities have posted information sheets in airports that caution people to wash their hands often and to stay home if they feel unwell.

The Race for a Vaccine

Despite the pandemic, mass events like concerts, football matches and festivals have not been canceled. However, health officials could change their minds quickly if the situation becomes acute. Temporary school closings are believed to be one of the more effective ways of containing an influenza outbreak. Experts see children as the most important carriers of the flu, because they tend to come into close contact with one another and often stick their fingers in their mouths and have poor hand hygiene. Hong Kong, for example, has taken the precautionary step of closing all kindergartens and primary schools for two weeks.

Vaccine manufacturers have already begun production of a vaccine against the pandemic virus, with the first batches expected to be ready in about four months. At that point, a fierce competition will ensue over who gets the protective vaccine. There will only be enough for a minority of the population.

WHO estimates that there will be enough vaccine worldwide for between 500 million and one billion people in the entire first year of the pandemic. Everyone else will be forced to wait and hope - and face the probability that the virus will reach them before a vaccine does.

Flu vaccines are traditionally grown in incubated chicken eggs. This is an effective method, but it has an important drawback, especially in a pandemic: It is impossible to produce large amounts of vaccine quickly, because one egg is needed for each dose of vaccine. To overcome this problem, a number of pharmaceutical companies are trying to convert their production to cell cultures.

Elderly Unaffected

In the western German city of Marburg, vaccine giant Novartis has, for the first time, successfully produced an initial batch of swine flu vaccine using cell cultures. “This proves that it works,” says Stephan Becker, director of the Marburg Institute of Virology, which works hand-in-hand with Novartis.

Cell cultures make it possible to produce vaccines within weeks instead of months. Novartis says it will begin human clinical trials with the cell-based vaccine in July, and the company plans to have the new vaccine ready for approval by December. If all goes well, millions of vaccine doses could leave the Marburg plant every week, while a new plant Novartis is building in North Carolina could produce even more.

The world will have to make do with rationing until there is enough vaccine for everyone. The WHO will soon issue recommendations on which patient groups are most endangered by the swine flu. They would be given priority for vaccination.

The most likely candidates are pregnant women, people with heart disease, diabetics, people with autoimmune disorders, the obese and those aged 30 to 50. Children will also likely be included. Although their symptoms are not usually severe, they tend to contract the virus in large numbers. In the Mexican town of La Gloria, one of the early sites of the epidemic, more than one in two children became infected.

Unlike the ordinary flu, H1N1 is apparently not particularly threatening to the elderly. Physicians speculate that this may be because they were exposed to a related virus many decades ago.

See Related: SWINE FLU QUESTIONS AND ANSWERS

See Related: SWINE FLU AND YOUR HEALTH ON PLANES

See Related: HEALTH CARE