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Controversial experiments on bird flu viruses could resume within weeks. They've been on hold for just over a year. NPR's Nell Greenfieldboyce reports that today, influenza experts around the world declared an end to an unusual research moratorium.
NELL GREENFIELDBOYCE, BYLINE: Last January, flu experts agreed to hold off on some studies that had caused a public outcry. The bird flu virus H5N1 isn't contagious in people, but scientists had genetically altered it. So it spread through the coughs and sneezes of ferrets, the lab stand-in for people. Critics charged that if these man-made germs escaped, they could potentially cause a pandemic.
Ron Fouchier is a virologist at Erasmus Medical Center in the Netherlands. He says everyone who signed on to the moratorium has now agreed to end it. The 40 scientists have published a letter saying so in the Journal of Science and Nature.
RON FOUCHIER: It means that 40 of the leading - world leading experts in influenza research seem to think that the benefits outweigh the risks.
GREENFIELDBOYCE: Fouchier and others originally did the experiment to understand the threat posed by H5N1. This virus circulates in poultry in parts of Asia and the Middle East. It rarely makes people sick. But over half of those known to have gotten sick have died. Researchers say in order to be prepared, it's vital to know how this virus could mutate in the wild and cause a natural pandemic. Yoshihiro Kawaoka is a scientist at the University of Wisconsin-Madison.
YOSHIHIRO KAWAOKA: The risk exists in nature already, and not doing the research is really putting us in danger.
GREENFIELDBOYCE: Kawaoka can't restart his experiments yet because he depends on funding from the U.S. government. And officials are still working out what experiments like this could be done with federal funding in the future and under what lab conditions. Still, scientists decided to lift the moratorium now because some countries have already completed biosafety and biosecurity reviews. And Fouchier says U.S. officials couldn't say how long their reviews would take.
FOUCHIER: And so as a consequence, it might take another one, two, three years. So how long do you want us to wait?
GREENFIELDBOYCE: Fouchier did his earlier experiments with U.S. funding but plans to restart soon, using money from other sources. One of the people who initially raised red flags about this work is Tom Inglesby. He's director of the Center for Biosecurity of the University of Pittsburgh Medical Center.
TOM INGLESBY: I don't think they should resume. I think the moratorium should go on because I think a number of questions remain unanswered.
GREENFIELDBOYCE: He says he's not convinced these experiments are necessary.
INGLESBY: There could be a time in the future where there is a highly compelling rationale to proceed which justifies the risks. I just personally have not seen that yet.
GREENFIELDBOYCE: And he worries about the risks that new flu viruses will get out of the lab if more scientists around the world start to do this type of research. Nell Greenfieldboyce, NPR News.