Schools are advised not to close anymore when they have cases.
This is the VOA Special English Health Report.
More than 20 countries have found cases of the new H1N1 influenza virus. In all around 1,500 cases and 30 deaths have been confirmed. But most have been reported in Mexico and, to a much lesser extent, the United States. The virus was discovered in Mexico in the middle of March.
On Tuesday, federal officials in the United States advised schools not to close anymore when they have cases. The new health secretary, Kathleen Sebelius, said the virus does not seem to be as severe as once thought.
The World Health Organization will not declare an influenza pandemic unless a virus becomes widespread in at least two areas of the world. The W.H.O. is advising people to wash their hands often with soap and water. And it says there is no risk of infection from eating well-cooked meat from pigs.
The virus is commonly called swine flu because it contains some genetic material from pigs. But it also contains material from humans and birds.
The World Health Organization, the United Nations health agency, uses a system of 6 phases to warn of possible influenza pandemics. The current system has been used since 2005. For the first time the W.H.O. raised its alert level from phase 4 to phase 5 on April 29th.
Phase 4 means that a virus has gained the ability to cause community-level outbreaks. Phase 5 is marked by human-to-human spread of the virus into at least two countries in the same area of the world. This declaration is meant to warn that the time to plan for a pandemic is short.
Phase 6 would mean a global pandemic. Still, this would only mean that there are community-level outbreaks in at least one other country in a different area of the world.
The threat of H1N1 may have eased in recent days. But public health officials point out that flu viruses can return more aggressively after a few months. That happened with the so-called Spanish flu of 1918 which killed millions worldwide.
In the 14th century, ships that arrived in Venice, Italy, from areas infected with bubonic plague had to stay outside port for 40 days. That was called quarantine, from a Latin word that means 40. Quarantine measures separate people from the general population if there are worries that they could be infectious.
And that's the VOA Special English Health Report, written by Caty Weaver. For the latest news, go to voaspecialenglish.com. I'm Mario Ritter.
quarantine: to exclude, detain, or isolate for political, social, or hygienic reasons（隔离）
