"Will The World’s Most Worrying Flu Virus Go Pandemic?" - Ed Yong
The Centers for Disease Control and Prevention (CDC) keeps a Most Wanted list for flu viruses. The agency evaluates every potentially dangerous strain, and gives them two scores out of 10—one reflecting how likely they are to trigger a pandemic, and another that measures how bad that pandemic would be. At the top of the list, with scores of 6.5 for emergence and 7.5 for impact, is H7N9. H7N9 has evolved, acquiring mutations that allow other flu strains to reproduce more effectively in both birds and mammals. It might also be a blessing in disguise that the high-path strains have emerged. The low-path strains were very hard to detect because they didn’t cause symptoms. But the high-path viruses kill infected birds, which means “they might be easier to eradicate from chickens since they can be more easily detected,” said Adolfo Garcia-Sastre, PhD, director of the Global Health and Emerging Pathogens Institute and professor of microbiology, medicine, and infectious diseases at the Icahn School of Medicine at Mount Sinai. “However, one would need a very well-organized eradication campaign to eliminate them from poultry before they spread to other areas beyond China. I’m afraid that this will not happen, since it did not happen with the H5N1 viruses, which were first detected in 1997, and finally disseminated to most of the rest of the world starting in 2003.”
- Adolfo Garcia-Sastre, PhD, Director, Global Health and Emerging Pathogens Institute, Professor, Microbiology, Medicine, Infectious Diseases, Icahn School of Medicine at Mount Sinai