h1n1 and pneumococcal lung infections?

WaPo | Federal health officials on Wednesday linked the H1N1 flu epidemic to a sharp rise in the number of severe bacterial infections.

Anne Schuchat, a physician at the Centers for Disease Control and Prevention, said the national trend was "worrisome" but not unexpected.

"In previous pandemics, there has been an increase in pneumococcal infections in younger people," she said.

The illnesses are caused by Streptococcus pneumoniae, a microbe often carried in the nose and throat. While often benign, the bacterium can cause bloodstream infections, fatal pneumonia and meningitis.

The clearest sign of the marked rise is coming from the Denver area, which usually records about 20 cases of "invasive pneumococcal disease" each October. This year, it has had 58, Schuchat said in a briefing for reporters.

Most invasive pneumococcal infections normally occur in the elderly, but in the Denver cases 62 percent were in people age 20 to 59, Schuchat said. Serious cases of influenza are also primarily hitting younger age groups.

When flu causes pneumonia, it can damage cells deep in the lungs, opening a portal for bacteria. In an analysis of about 75 fatal H1N1 cases earlier this year, autopsies showed that about one-third had bacterial pneumonia.

Pneumococcal infections are largely preventable with a vaccine that is given once or twice depending on a person's age. It is recommended for smokers and for people with asthma, kidney or liver problems, heart disease and other chronic ailments. Only about one-quarter of people with those conditions, however, have been vaccinated.