New Strain of Bird Flu Jumps to Humans
Bird flu or avian influenza is caused by viruses that occur among wild aquatic birds and can be transmitted to domestic animals. It’s rare for humans to catch these viruses but – as we’ve learned from the H5N1 strain that has taken the lives of some 600 people since it broke out in China in 1996 — not impossible. So learning that a 20-year-old Taiwanese woman has been infected with the new strain of bird flu, H6N1, has left scientists concerned that a new pandemic could occur.
H6N1 has been circulating widely among chickens in Taiwan. Previously, scientists had not thought humans could contract this virus. But the throat swabs of a young Taiwanese woman who was hospitalized in May with a lung infection have proved otherwise. These have revealed that she had H6N1, the Taiwan Centers for Disease Control says.
How the woman got the virus remains unknown. She worked in a deli and a number of her close family and friends also had flu-like symptoms after being in her presence; none, though, tested positive for H6N1. She was released from the hospital after being treated with Tamiflu and antibiotics.
“The question again is what would it take for these viruses to evolve into a pandemic strain?” as Marion Koopmans, a virologist at the National Institute for Public Health and the Environment in the Netherlands, writes in a commentary accompanying report about the Taiwanese woman in The Lancet.
Scientists monitor birds who’ve become infected to try to figure out which viruses might be the most dangerous to humans. It’s been especially worrisome to researchers that birds infected with H6N1 or another new strain of bird flu, H7N9, do not themselves appear to be very sick.
Taiwanese scientists hypothesize that some version of the virus in chickens could have “transformed just enough to be able to latch onto cells in the human nasal and airway passage” — meaning that this type of bird flu could spread via the air.
In more hopeful news, two pharmaceutical companies have separately reported that an experimental vaccine for H7N9 has been successful in early-stage trials. Since last spring, at least 137 people have been infected with H7N9 and at least 45 have died in Asia, meaning that, for about one-third of those who become infected with the virus, their illness is fatal.
What’s more, millions of doses of the vaccine for H7N9 can be manufactured quickly. That’s of paramount importance should a virus — and certainly one as lethal as H7N9 — start spreading, to avoid a pandemic occurring. Details about a vaccine made by Novavax, a biotech company based in Rockville, Maryland, were published on Wednesday in the New England Journal of Medicine. Swiss drugmaker Novartis reported on its positive findings on Thursday.
In a world in which diseases can travel around the world via one passenger on an airplane flight, such vaccines could save lives and halt the spread of a deadly illness. As researchers wrote in The Lancet about H6N1, “these viruses continue to evolve and accumulate changes, increasing the potential risk of human-to-human transmission. Our report highlights the continuous need for preparedness for a pandemic of unpredictable and complex avian influenza” that has now proved to be able to infect us.
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