The virus, which is thought to have originated in Mexico, has now spread as far south as Australia and as far east as Japan. With over 170 reported cases, Japan has one of the highest instances of infection in Asia.

In response, Japan, like many other badly infected regions, has tried to contain any further spread of the virus. One measure taken has been the temporary closure of 4,000 schools, colleges and nurseries in and around Hyogo and Osaka.

Students have been advised to stay at home until further notice but a few restless individuals have found a more entertaining and musical way to spend their new-found free time.

It appears some Japanese students are not spending their time worrying about the virus, but spending it practising their singing instead.

In fact, a few karaoke club owners in Japan have reported record numbers of customers. One club manager told the AFP news agency: "We suddenly had a number of high school students after 2pm yesterday, right after the announcement that schools would close for a week."

Neither students nor club owners appear overly worried about the virus. So just how concerned should they be?

Well, according to a recent statement from Dr Margaret Chan, Director General of the World Health Organization:

"With the exception of the outbreak in Mexico, which is still not fully understood, the H1N1 virus tends to cause very mild illness in otherwise healthy people. Outside Mexico, nearly all cases of illness, and all deaths, have been detected in people with underlying chronic conditions."