New York City has so far closed 40 schools in an attempt to slow the spread of A/H1N1 flu within the school community, according to a press release issued by the city's Health Department on Friday.

The Health Commissioner Thomas R. Frieden and Schools Chancellor Joel I. Klein on Friday discussed the rationale behind closing individual New York City schools in response to the presence of the A/H1N1 virus in New York City.

All evidence suggests that the new virus is causing a large proportion of the city's current flu cases, says the press release.

The main goal of school closures is to protect those at highest risk of complications from flu in that particular school community -- students, staff, and their close contacts who are under 2 or over 65 years of age, pregnant, or who have a chronic medical condition such as asthma or diabetes, says the press release. "School closure is not done with the expectation that it will interrupt the spread of flu in the city as a whole."

"The new A/H1N1 virus is here in New York City," said Frieden. "Many school children have mild flu, as they do each flu season. We are closing certain schools in an effort to slow transmission within the school community and protect those at highest risk of complications from flu."

"In some instances when many children are sick, closing a school and keeping children home can reduce further infection. We continue to work alongside the Health Department in monitoring schools and closing them when the Health Department so recommends," said Klein.

The Health Department and the Department of Education work together to monitor daily flu-like illness in New York City schools. School nurses notify the principal and contact the City's Office of School Health if there are five or more children who come to the medical room and who have a fever that meets the standard definition of being over 100.4O (38 degrees Celcius) accompanied by either cough or sore throat.

Once that threshold is reached, the Health Department reviews daily flu-like illness among students coming to the medical room, as well as absenteeism data over the past week. The Health Department looks for either a sudden or a sustained increase in flu-like illness.

According to the press release, every school with a cluster of students with flu-like illness is monitored daily. High absenteeism, by itself, is not a basis for closure. If parents keep sick children home, it can reduce transmission and the risk to vulnerable people

The Health Department pays closest attention to schools in which over 1-2 percent of the student body comes to the medical room on a given day with fever and cough or sore throat. This indicates that a significant number of students are ill while at school and may be spreading infection to those at risk.

(Xinhua News Agency May 23, 2009)