Record flu season finally ends
The 2004-05 flu season started out with mass panic because of vaccine shortages, lasted longer than usual and finally has ended with a record number of reported cases.
With just two suspected cases of influenza documented in the past two weeks, the Allegheny County Health Department on Wednesday announced it will stop its formal surveillance and reporting program, signifying the official close of flu season, department spokesman Guillermo Cole said.
"We're glad to put this one to bed," Cole said. "It was a long season, and we feel it's time to call it a day."
Unlike most flu seasons, which typically end in late March or early April, flu activity remained high in March and continued at lower, but still notable, levels throughout April before waning this month.
Altogether, 940 influenza cases were reported in Allegheny County in the 2004-05 season, breaking the record of 709 cases set last year. This count includes 395 cases of flu confirmed by laboratory analysis and 545 suspected cases diagnosed through a rapid test at doctors' offices.
Almost 80 percent of the cases were Type A Wyoming or Fujian-like virus strains. The remainder were Type B Shanghai or a mixture of Types A and B.
It's hard to know whether the local rise in influenza activity is due to an actual increase in caseload, Cole said.
"There could be more actual flu, but we know there's more testing, and that's driving the numbers up," he said.
Furthermore, for every case of the flu identified through testing, it is estimated that hundreds of others go unreported and therefore uncounted.
It's also difficult to assess the impact of the flu vaccine shortage on this year's case count, Cole said.
In October, major flu shot supplier Chiron Corp. pulled 46 million to 48 million flu shot doses off the market after British authorities suspended the company's license.
That created a nationwide shortage that forced doctors and health providers to deliver flu shots only to high-risk people -- those older than 65 or between 6 and 23 months old, as well as people with chronic respiratory diseases -- who withstood long lines and cold weather to be immunized.
Senior citizens accounted for about 38 percent of the season's caseload, but this high toll on the elderly is not unprecedented, Cole said.
"There certainly weren't as many people vaccinated nationally and probably locally as in past years, but we did our best to try to get the vaccine to the people who needed it the most," Cole said.
The U.S. Centers for Disease Control and Prevention has yet to issue its season-end influenza report, CDC spokeswoman Christine Pearson said.
As of the CDC's last update for the week ending May 7, 28 states -- including Pennsylvania -- and New York City reported sporadic flu activity, Pearson said.