FORGET SARS..DON'T LET A BIRD CRAP ON YOUR HEAD IN THE NETHERLANDS
(April 23) -- It's not as scary as SARS -- yet. But world health experts are keeping a nervous eye on the Netherlands, where an out-of-control bird flu recently killed its first person.
So far, 82 people -- all in the Netherlands -- have come down with the bird virus. Three of them caught it from another person. The virus causes pinkeye in most people, but some get flu symptoms. One was a 57-year-old veterinarian. He developed double pneumonia and died.
Albert D.M.E. Osterhaus, PhD, DVM, studies new viruses at the Institute of Virology, Erasmus University, Rotterdam, Netherlands. His lab was the first to prove that the SARS virus is the sole culprit in the ongoing SARS outbreaks. Even though he's continuing to study SARS, he keeps an eagle eye on bird flu. It's known to science as highly pathogenic avian influenza or HPAI.
"The chance of something awful happening from HPAI is very small," Osterhaus tells WebMD. "But even a very small chance of something very terrible is something to take seriously. If this would lead to pandemic influenza, that would have major consequences."
This is what keeps world health experts up at night, says medical epidemiologist Marjorie P. Pollack, MD. Pollock is a disease-surveillance monitor for the International Society of Infectious Diseases.
"The big concern for a pandemic is getting a new flu strain that nobody already has immunity against," Pollack tells WebMD. "With current human flu viruses you see shifts and drifts that let them infect some people who've had it before, but usually you see strains that a significant number of people remain protected against."
The bird flu is sweeping Netherlands and has broken into Belgium. In their effort to contain the virus, authorities have killed some 10 million chickens. It's not a new virus, but it's usually not very deadly. In fact, a less deadly outbreak in eastern Connecticut is being contained with a mass vaccination program. A similar, relatively harmless virus likely came to Netherlands in migrating ducks or geese. Somehow, it mutated into HPAI or what used to be called fowl plague.
Why this virus is infecting so many humans isn't clear, says Arnon Shimshony, DVM, retired chief veterinary officer for Israel and a professor at Hebrew University, Jerusalem.
"This is a very unusual occurrence," Shimshony tells WebMD. "Lethal infection from birds to humans happened in Hong Kong in 1997. Several people died, but that was a different kind of virus, H5N1. This is H7N7, which usually does not infect humans. It is a bit concerning. Even the conjunctivitis [pinkeye] is unusual. In the past we didn't see this."
Despite its devastating effect on birds, the virus doesn't usually cause serious disease in humans. Most often it takes a pretty severe exposure to infected chickens for a person to get it. The three cases of human-to-human spread are worrisome -- but it's still not a virus that spreads easily in people.
So why worry? Flu viruses do a trick called substitution. If a person gets infected with two flu viruses at the same time, the two viruses can swap genes. When this happens, a bird virus can become a human virus. In a colossal case of bad timing, the bird flu hit the Netherlands at the peak of the human flu season. That's now coming to an end.
Fortunately there's no sign yet that this has happened. It's still not clear why the virus killed the veterinarian, but there's reassuring news. Osterhaus says that the virus he carried was still fully a bird virus. It hadn't picked up genes from any human flu virus.
To be on the safe side, Dutch officials recommend human flu vaccine or Tamiflu for those who come in regular contact with chickens. The idea is to keep them from getting a human flu that might mix with the bird flu.
On the scarier side, it looks as though the bird virus has infected pigs on some farms. Pigs, Pollack notes, are a kind of mixing pot for flu viruses.
The bird flu epidemic in Netherlands and Belgium is not the same virus currently affecting chickens and pet birds in California, Nevada, Arizona, and parts of Texas. The cause of the American epidemic is exotic Newcastle disease. It's deadly to chickens -- and it, too, causes pinkeye in people who handle the animals. While the disease is a terrible blow to the poultry industry in affected areas, it's not considered a threat to humans.
SOURCES: Program for Monitoring Emerging Diseases (ProMED) web site, International Society for Infectious Diseases, accessed April 23, 2003. Albert D.M.E. Osterhaus, PhD, DVM, Institute of Virology, Erasmus University, Rotterdam, Netherlands. Arnon Shimshony, DVM, professor, Koret School of Veterinary Medicine, Hebrew University of Jerusalem, Israel. Marjorie P. Pollack, MD, associate editor and medical epidemiology and surveillance moderator, ProMED, International Society for Infectious Diseases; independent consultant medical epidemiologist; and part time clinical attending physician, Harlem Hospital Emergency Room, New York.
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