The Associated Press

Vaccinating schoolchildren against the flu protects elderly people from the sometimes deadly virus, too, according to a huge study in Japan, the only country ever to focus flu-control efforts on youngsters.

From the mid-1970s through the 1980s, about two-thirds of Japanese schoolchildren were vaccinated under a government program. The number of flu deaths dropped by about 43,000 each year, mostly among the elderly, amounting to one death prevented for every 420 children vaccinated.

When the government phased out the program in the 1990s, death rates from the flu and its complications returned to their prior level, according to researchers in Japan and at this country's National Institute of Allergy and Infectious Diseases.

They concluded that vaccinating schoolchildren, the group that spreads flu the most, helps protect senior citizens.

``It's a pretty clever idea,'' said Dr. Stephen Gluckman, chief of infectious disease clinical services at University of Pennsylvania Medical Center. He said the strategy should be considered in the United States.

Health programs here and most developed countries focus flu-prevention efforts on groups most likely to develop complications such as pneumonia. The Centers for Disease Control and Prevention recommends annual flu shots for people 50 and older, and for anyone with chronic medical problems, particularly children with asthma.

Lone Simonsen, an expert in epidemiology at the NIAID, said that although more elderly people live with their families in Japan than in this country, ``my own hunch is that you're probably going to get the same protective effect'' in the United States if children are vaccinated.

The study was reported in Thursday's New England Journal of Medicine.

A CDC advisory panel is considering adding children under 5 to the recommended groups, but Dr. Carolyn Bridges, a medical epidemiologist in the CDC's influenza branch, said that presents logistical problems.

Besides swamping health care workers with millions more people seeking flu shots in October and November, pharmaceutical companies would have to boost production.

Drug companies get just six months to make the vaccine doses, once scientists determine which strains are most likely to circulate during the coming winter. Last fall, the vaccine was delayed because one virus strain was difficult to grow.

Copyright 2001 The Associated Press. All rights reserved.