Cases of H1N1 influenza -- also known as swine flu -- peaked late last month in Allegheny County and the worst of it may be over even as the traditional flu season looms ahead.

Dr. Jim Lando, on assignment with the Allegheny County Health Department from the U.S. Centers for Disease Control and Prevention, told the county Health Board yesterday that 9 percent of the people visiting emergency rooms at eight hospitals in the county last week reported flu-like symptoms, down from 17 percent on Oct. 24 and 25.

"I think we've seen the peak, at least I hope so," said county Health Department Director Bruce Dixon. "The number of emergency room visits is dropping and at this rate the outbreak should be over by the end of November. We may have made it through this despite the lack of a vaccine supply."

Dr. Stephen Ostroff, acting physician general for Pennsylvania, said the state Health Department has identified a similar downward trend in flu cases in southwestern Pennsylvania, but not in the rest of the state.

"We too are seeing some signals of flu decline in southwestern Pennsylvania from the data we collect on emergency room visits, school absenteeism and confirmed influenza cases," Dr. Ostroff said. "Because the flu hit that part of the state earlier than others, the decline makes sense. But before we're ready to say it's passed its peak, we want to see more data."

Despite the decline in flu cases in Allegheny County, he said all regions of the state continue to experience widespread flu activity, especially in people between the ages of 6 months to 24 years.

"The amount of reporting of influenza in all parts of the state, including the Southwest, remains higher than anything we've seen for the seasonal flu since 2003," Dr. Ostroff said. "We don't want to say the flu is going away just yet. We don't want to give people a reason to slack off doing things like staying home if they feel sick, covering their mouths when they sneeze, washing their hands or taking the opportunity to get the flu vaccine when it's available."

Statewide, there have been almost 7,000 confirmed cases of H1N1 flu since April when its first outbreak occurred, with 5,000 of those occurring since Sept. 1 and more than 1,700 of the total in the last two weeks. Many thousands more people have had flu symptoms but not sought medical treatment. More than 99 percent of all the flu cases in the state so far have been of the H1N1 variety.

"Even if we start to see flu cases decline across the state," Dr. Ostroff said, "let's not forget that the seasonal flu season is right around the corner."

Some health care professionals are saying that because of the swine flu outbreak, the seasonal flu may be crowded out or "subplanted" this year, as it was in Argentina. But Dr. Ostroff said that situation was different and shouldn't be counted on when making a decision about getting a flu vaccine.

Yesterday, the state Health Department urged all health care professionals to be vaccinated against the H1N1 flu, and said a statewide vaccination campaign targeted to health care workers will be launched soon.

"We're working to inform every health care worker of how many lives they can protect by their decision to get vaccinated," said Secretary of Health Everette James. "They not only will protect themselves, but also their families, their patients and their co-workers."

Other priority groups to receive the vaccine include young people to age 24, pregnant women, household contacts and child care providers for those under 6 months, and those under 65 with underlying health conditions. Members of those groups should contact their health care providers to learn if the H1N1 vaccine is available.

Dr. Ostroff said the state has received more than 1 million doses of H1N1 vaccine so far but was supposed to have twice that amount by now.

Dr. Dixon said many Allegheny County senior citizens remain "under-immunized" for the regular flu and urged them to get shots for the regular flu and the swine flu vaccine when it becomes available.

"We've done some planning and talking with schools and physicians' offices," Dr. Dixon said, "and if we get the doses we've been promised in the next couple of weeks, we'll make sure they're made available."

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