Internet users have ramped up their searching, chatting and blogging of up-to-the-minute news on the symptoms and spread of swine flu since its sudden appearance this month.
It's a trend health experts say is effective in rapidly pushing out public health information, using technology not available during the deadly, worldwide flu outbreaks of decades past.
It's also creating a double-edged sword, they say, in having too many sources of data — some of which are not based in science, such as the sea of microblogging "tweets" on the social-networking site Twitter.
"A huge number of people at home have the ability to search for disease symptoms," says Gabe Kelen, a physician and chair of the emergency department at Johns Hopkins University. The quality of information, he says, "largely depends on what sites they go to."
Search-engine giants Yahoo and Google saw spikes in searches of phrases such as "swine flu symptoms" or "swine flu pandemic" early this week: "Swine flu" rose to the top of Yahoo's searches this week.
Similar terms on Google increased by more than 20-40 times, compared with its monthly average of hits of such key words, a USA TODAY analysis shows.
On Twitter, the fast-growing microblogging site, swine-flu-related posts crested past 10,000 an hour Tuesday, according to Mashable.com.
"There is a lot of chatter that's going on where people can make anecdotal comments — those that aren't so substantial in the science," warns Robert Kim-Farley, a professor at UCLA's School of Public Health and director of communicable disease control and prevention at the Los Angeles County Department of Public Health.
Useful sites, however, present "a nice opportunity to get factual and good information through the Internet," he says.
The Web is driving new disease-tracking and prevention tools:
•Kirkland, Wash.-based Veratect, whose CEO says his researchers spotted swine-flu trends earlier this month, is posting updates on Twitter (username: veratect). The posts had about 3,800 "followers" by late Tuesday, CEO Bob Hart says.
•Los Angeles County's health department has created a YouTube channel with swine-flu resources for both health professionals and the general public (youtube.com/lapublichealth).
•Gizmodo.com fastened together a Google Maps "mash-up" that plots new swine-flu cases in real time.
"We have a situation where there are a lot of unknowns with how this virus is going to behave," Kelen says. "In one way, information can get out quite quickly."