GENEVA (Reuters) - Most H1N1 flu patients do not require antiviral therapy to recover, but it remains important to develop a pandemic vaccine as there is a risk of future drug resistance, a World Health Organisation expert said on Tuesday.
Nikki Shindo, a medical officer with the WHO's global flu programme, said the U.N. agency would soon publish new guidance about how to treat patients with the virus that has caused mainly mild symptoms outside of Mexico.
Given most patients can recover with rest and hydration, Shindo said there did not appear to be a need to treat all people infected with the strain with Tamiflu, Relenza, and similar antiviral drugs.
Saving such stockpiles for pregnant women and patients with underlying health conditions such as cardiovascular disease or diabetes may prove most prudent, she told a news conference.
"We will recommend to consider the use of antivirals for high risk groups," Shindo said, while allowing that because little is known about the new strain, it was possible antiviral drug use could be reducing its impact in Europe and elsewhere.
"It could be the reason why we are seeing less severe cases in Europe," she said in response to a journalist's question.
But comparisons between regions were difficult due to a lack of control studies.
Shindo told reporters that about 10 percent of people known to have been infected with the strain known popularly as "swine flu" in Mexico and the United States required to be admitted to hospital -- far more than seen in regular seasonal flu.
"That I think has rightly urged the development and delivery of pandemic influenza vaccine," she told a news conference.
"We are also facing the risk of having resistant viruses," she said, noting that antiviral drugs like Tamiflu and Relenza have varying effectiveness against flu viruses as they mutate.
"Given that we will have winter in southern American countries and also other parts of the southern hemisphere, there will be a risk of having viruses that will be highly resistant to antivirals," Shindo said.
(Reporting by Laura MacInnis and Stephanie Nebehay)
