Vietnam will import a second antiviral medicine, Zanamivir, for treating swine flu in people whose bodies have become resistant to Tamiflu, Deputy Minister of Health Trinh Quang Huan said.

The more Tamiflu is used, the more likely resistance is built up, he said.

Huan stressed that resistance to any drug is a possibility, so having an alternative in Zanamivir, which is inhaled, will make it easier to treat people who are resistant to Tamiflu.

His ministry has already been approached by GlaxoSmithKline (GSK) Vietnam, but is yet to determine which drug is costlier.

So far resistance to Tamiflu has been recorded in Japan, Denmark, the US and a few other countries.

On Tuesday, Huan reported that the influenza A (H1N1) virus has been detected in 48 of Vietnam’s 63 provinces and cities.

Around half of the nearly 3,000 people infected have recovered and been discharged from hospital.

In a study released the same day, the University of Maryland said the H1N1 virus does not readily combine with seasonal flu strains that could foster a more virulent mutant flu, AFP reports.

“The H1N1 pandemic virus has a clear biological advantage over the two main seasonal flu strains and all the makings of a virus fully adapted to humans,” explained virologist Daniel Perez of the University of Maryland-based Prevention and Control of Avian Influenza Coordinated Agricultural Project.

The pandemic virus is more infectious, simply because it’s new, so hosts haven’t had a chance to build immunity yet. The older strains, meanwhile, encounter resistance from hosts’ immunity to them, Perez said.

However, the study, which appears in the online journal PLOS Currents, found that some animals infected with both the new virus and earlier seasonal viruses developed respiratory symptoms and intestinal illness as well.

Perez and his team urged more research to see if such co-infection and multiple symptoms could explain some of the deaths attributed to the new virus.

“Our findings underscore the need for vaccinating against the pandemic flu virus this season. The findings of this study are preliminary, but the far greater communicability of the pandemic virus serves as a clearly blinking warning light,” Perez concluded.

Source: Thanh Nien, Tuoi Tre, AFP