Scientists have established for the first time that a new strain of bird flu which has killed 36 people in China is, in some cases, resistant to pharmaceutical company Roche's widely-used flu drug Tamiflu.
Doctors from Shanghai and Hong Kong, writing in The Lancet medical journal on Tuesday, reported three of 14 patients with the H7N9 virus who were studied in detail did not respond to neuraminidase inhibitors - a group medicines, including Tamiflu, that currently offer the only known treatment option.
In one patient, the gene mutation responsible for resistance appears to have arisen after infection took hold, probably as a result of treatment with Tamiflu, leading to concerns resistance may occur as a result of drug treatment.
© 2026 Thomson/Reuters. All rights reserved.