Health officials in Vietnam’s Khanh Hoa province have confirmed an H5 avian flu infection in a 21-year-old university student, though there are no details yet on the strain or how the patient contracted the virus.

Details about the case were reported in Vietnamese media reports translated and posted by Avian Flu Diary, an infectious disease news blog. An official statement on the case from provincial health officials was translated and posted by FluTrackers, an inflection disease news message board. Khanh Hoa is on Vietnam’s southeastern coast.

Man hospitalized in serious condition

The patient’s symptoms began on March 11, and he returned home a few days later, where he stayed with his mother and sister while seeking medical care. When his symptoms worsened, he was hospitalized at a regional hospital. Soon after, he was transferred to Khanh Hoa provincial hospital where healthcare workers collected samples and sent them to the Pasteur Institute in Nha Trang, which revealed the H5 influenza virus.

The man is hospitalized in serious condition and in isolation at the Provincial Hospital of Tropical Diseases. Health officials are monitoring contacts, including family members, health workers, and university students.

So far, the subtype isn’t known, but a few human cases involving older and recent H5N1 virus clades have been reported over the past few years, and China and Laos have reported H5N6 infections.

The reports didn’t say how the patient likely contracted the virus.