UPDATE 1-Wyeth seeks approval for Prevnar in Japan-source

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TOKYO, Sept 26 (Reuters) - U.S. drugmaker Wyeth will file a new drug application in Japan on Wednesday for its Prevnar vaccine that helps prevent pneumonia, meningitis and ear infections in children, a company source said.

The highly successful vaccine, also known as Prevenar outside North America, acts against the pneumococcal bacteria and has fueled healthy profit growth for Wyeth as countries such as Britain, Germany and Mexico launched national immunisation programmes.

Pneumococcal bacteria can trigger illnesses that include bacterial pneumonia, bacteremia or blood poisoning, and middle ear infections.

According to a study published in April this year, the vaccine has slashed pneumonia hospital admissions for U.S. babies and toddlers -- dropping 39 percent by the end of 2004 compared to rates in the years before debut of the vaccine in 2000.

That translates into a decline of 41,000 pneumonia hospitalisations prevented for children under age 2 in 2004.

There are currently no medical agents approved in Japan for the prevention of invasive pneumoccocal disease in children.