A new strain of bird flu that scientists believed was reserved for chickens and could not infect people has shown up in a Taiwanese woman.
Investigators were at first baffled as to how she had become infected, ABC News reports. This shows scientists must do more to spot worrisome flu strains before they ignite a global outbreak, doctors say.
The 20-year-old woman was hospitalized in May with a lung infection. After being treated with Tamiflu and antibiotics, she was released. But a throat swab sent to the Taiwan Centres for Disease Control identified the flu strain as the H6N1 bird flu, which is widespread in chickens on the island. The patient, who was not identified, worked in a deli and had no known connection to live birds.
Doctors noted that several of the young woman’s close family and friends also developed flu-like symptoms after spending time with her, though none tested positive for H6N1.
Marion Koopmans, a virologist at the National Institute for Public Health and the Environment in the Netherlands, stated in a commentary accompanying the new report published Thursday in the jurnal Lancet Respiratory Medicine, that it is worrisome that scientists had no early warning signals that such new bird flus could be a problem until humans fell ill.
Scientists often monitor birds to see which viruses are killing them, in an attempt to guess which flu strains might be troublesome for humans — but neither H6N1 nor H7N9 make birds very sick.
Since the H5N1 bird flu strain first broke out in southern China in 1996, it has killed more than 600 people, mostly in Asia, reports Popular Science. Several other bird flu strains, including H7N9, which was first identified in China in April, have also caused concern among public health officials, but none has so far mutated into a form able to spread easily among people.
“The question, again, is what would it take for these viruses to evolve into a pandemic strain?” wrote Marion Koopmans.
Koopmans called for increased surveillance of animal-flu viruses and more research into predicting which viruses might cause a global crisis.“We can surely do better than to have human beings as sentinels,” she wrote.
On a more hopeful front, Popular Science reports, two pharmaceuticals separately reported encouraging results from human tests of a possible vaccine against a different type of bird flu that has been spreading in China since first being identified last spring, which is feared to have pandemic potential.
The vaccine news is on the H7N9 bird flu that has infected at least 137 people and killed at least 45 since last spring. Scientists from Novavax Inc., a Gaithersburg, Md., company, say tests on 284 people suggest that after two shots of the vaccine, most made antibodies at a level that usually confers protection.
Results were published online Wednesday by the New England Journal of Medicine.
In a separate announcement on Thursday, Switzerland-based Novartis announced early tests on its H7N9 vaccine in 400 people showed 85 percent of them got a protective immune response after two doses. The data has not yet been published.