Washington - Officials said that 21 schools of Bedford county in southern Virginia had been closed, on Wednesday, to clean them for the prevention of the spread of a dangerous bacterial infection that killed a 17-year-old high school student.

The student died from a drug-resistant staph infection known as Methicillin-resistant Staphylococcus aureus (MRSA). It has become distressing public health issue nationwide.

Charles Pyle, spokesman for the Virginia Department of Education, said that the schools in Bedford County were closed to allow officials to carry out a thorough cleaning in an effort to get rid of bacteria responsible for these infections.

2 schools of a small rural district in Rappahannock County in the state’s northern part closed for a day last week due to MRSA concerns.

Parker said, “VDH (Virginia Department of Health) considers it to be sort of ubiquitous but not a public health threat any more today than it was yesterday or the day before.”

To reduce the risks of infection, the state education department is asking school districts statewide to contact the health authorities.

In 2005, MRSA killed about 19,000 Americans and made 94,000 seriously ill MRSA, according to research published in Journal of American Medical Association.

Staph bacteria are found on the skin or in the nose of about a third of the population. They cause pimples or rashes but cause severe infections in the lungs, kidneys and other organs.

U.S. Centers for Disease Control and Prevention estimates 1 percent of population carries MRSA, without any symptoms.

Antibiotics can treat MRSA infections.