Monday, July 5, 2004; Page A11
Strain of Avian Flu Evolving
Scientists in China have disturbing news about a strain of the flu virus circulating among ducks in Asia -- the virus is getting progressively more lethal to mammals.
Hualan Chen of the Harbin Veterinary Research Institute and colleagues isolated 22 samples of the H5N1 influenza virus from ducks in mainland China from 1999 through 2002 and then injected strains of the virus from various years into chickens, mice and ducks.
None of the strains made ducks sick. But most of the strains were highly dangerous to the chickens. And in mice, the virus became progressively more lethal over time, with samples isolated in 1999 and 2000 significantly less deadly than those isolated in 2001 and 2002.
After analyzing the genetics of the viruses, the researchers concluded that the virus had mutated over time to become more lethal.
The research is alarming, because the virus jumped to people in Hong Kong in 1997, causing six deaths.
"Our findings suggest that immediate action is needed to prevent the transmission of highly pathogenic avian influenza viruses from the apparently healthy ducks into chickens or mammalian hosts," the researchers wrote in a paper released last week in the Proceedings of the National Academy of Sciences.
-- Rob Stein
Census to Plumb Arctic Depths
Scientists will venture into the field next month to conduct the first census of the Arctic Ocean, including an ice-lidded, 3,800-meter-deep bowl of water the size of Alaska. The project will cost $10 million to $20 million, and is an effort to identify species that could be affected by global warming. It is due to be finished by 2010.
Russ Hopcroft, an assistant professor at the University of Alaska Fairbanks who is helping oversee the study, said the international group will explore everything from the sea ice community to invertebrates on the ocean floor.
"There's an urgency to know what's there before we lose it," Hopcroft said. He said the Arctic may have already lost 40 percent of its permanent ice pack because of the rise in Earth's temperature.
Many species that live in the depths of the Canada Basin that researchers will focus on do not travel to shallower waters and are believed to have been isolated for millions of years. Scientists hope to discover living fossils, species that were thought to have gone extinct but may have survived undetected in the Arctic.
"We really need to know much better what's going on in the Arctic right now," Hopcroft said.
-- Juliet Eilperin
Drug Ads Depict More Women
Women are substantially over-represented in advertisements for psychiatric drugs and are usually shown as being submissive, sexy or asleep, according to an analysis that compared ads over a 20-year period in three flagship psychiatry journals.
The stereotyped depictions of women in the ads contrasted with those of men, who were usually shown in active, professional roles. A comparison of U.S., British and Canadian journals in 1981, 1991 and 2001 found that the proportion of ads featuring women increased in the U.S. and Canadian journals. In 2001, no men were shown in ads for antidepressants in the American Journal of Psychiatry. Overall, 88 percent of the drug ads depicted white people.
Although there were roughly equal numbers of men and women in ads in 1981, the number of women had soared to 80 percent in the Canadian Journal of Psychiatry and 88 percent in the American Journal of Psychiatry by 2001.
"The effect of these advertisements on physician perception, diagnosis, and prescribing is unknown but may be substantial," the researchers wrote. "Future advertisements for psychotropic drugs should seek more balanced representations of gender and race."
The analysis was published in the Journal of Nervous and Mental Disease and reported last week in a newsletter of the American Psychiatric Association.
The authors wrote that "despite the great diversification and expansion of women's roles over the last 20 years, there is a consistent tendency in pharmaceutical advertising to represent women submissively or even in a sexualized manner in traditional settings and roles."
-- Shankar Vedantam
© 2004 The Washington Post Company
Officials dispose of ducks in South Korea, where avian flu was reported in December. One strain is reportedly becoming more lethal to mammals.
(Chung Jae-hoon -- Newsis Via Reuters)
_____Avian Flu Facts_____
Q. What is avian flu?
A. Avian influenza is an infectious disease of birds caused by type A strains of the influenza virus. The disease, which was first identified in Italy more than 100 years ago, occurs worldwide.
Q. Is avian flu contagious?
A. Yes. All birds are thought to be susceptible to infection with avian influenza, though some species are more resistant to infection than others. The first documented infection of humans with an avian influenza virus occurred in Hong Kong in 1997, when the H5N1 strain caused severe respiratory disease in 18 humans, of whom 6 died.
Q. What are the symptoms of avian flu?
A. Published information on human infection is limited to studies of the 1997 Hong Kong outbreak. Symptoms included fever, sore throat, cough and, in several of the fatal cases, severe respiratory distress secondary to viral pneumonia.
Q. How do you treat avian flu?
A. The quarantining of infected farms and destruction of infected or potentially exposed flocks are standard control measures aimed at preventing spread to other farms and eventual establishment of the virus in a country’s poultry population.
Q. How can you protect yourself against avian flu?
A. Workers involved in the culling of poultry flocks must be protected, by proper clothing and equipment, against infection. These workers should also receive antiviral drugs as a prophylactic measure.
Q. How effective is the vaccine?
A. Vaccination of persons at high risk of exposure to infected poultry, using existing vaccines effective against currently circulating human influenza strains, can reduce the likelihood of co-infection of humans with avian and influenza strains.
• WHO Fact Sheet
• CDC: Avian Flu Information
Source: World Health Organization