Taiwan just reported the first confirmed case of the bird flu H7N9 to have spread outside of mainland China. The patient is a 53-year-old man who had recently returned from Shanghai and Suzhou, along China’s eastern coast.
However, more than simply indicating the avian flu’s expanding geography, the case suggests the possibility of human-to-human transmission. Of 110 health care workers treating the patient, three have since come down with flu-like symptoms, despite the fact that they were wearing protective medical gear, said the Taiwan Centers for Disease Control on its website.
The patient told the CDC that he had neither been exposed to birds or poultry, nor had eaten any undercooked eggs or poultry.
To date, both the Chinese government and the World Health Organization have said that human-to-human transmission hasn’t been documented. However, nor have they ruled it out as a possibility, and they’ve indicated that the source of the virus is still uncertain. That said, the shuttering of Shanghai’s live poultry markets on April 6 had slowed the incidence of new cases, Anne Kelso, director of the WHO’s flu center told the Wall Street Journal (paywall).
Human-to-human transmission implies a higher degree of contagiousness than if the flu were caught from contact with birds alone. It would make the spread of the virus, which has so far killed 22 people out of 108 infected, much more difficult to contain.
The CDC also reports that, of 139 people who have been in contact with the Taiwanese patient, three failed to wear protective medical gear, but had not so far come down with any symptoms.
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