Updated

A page on a Google-operated Web site appears to forecast influenza outbreaks by tracking the volume of people who use the search engine to send queries about flu symptoms.

If the Google data is correct, then Arkansas is experiencing a moderate outbreak of the flu. But doctors at the Arkansas Health Department said Wednesday that Google can't be correct because there has not been one confirmed case of the flu in Arkansas this season.

The Centers for Disease Control and Prevention in Atlanta collects data on flu cases from across the country and determines the locations and severity of outbreaks. The agency also checks for what types of flu virus are being found. Google processes the number of searches about flu-related topics.

A graphic on Google's trends site — google.org/flutrends — shows a remarkable similarity between search activity related to flu-like illness and outbreaks of the virus from 2004 through 2008. The site acknowledges that not everybody searching is sick but says "a pattern emerges when all the flu-related search queries from each state and region are added together."

The site says the search-engine inputs give a quicker picture of where the illness is spreading than the CDC reports, which take more time to be assembled.

Why then the indication that Arkansas is seeing flu cases?

Dr. Sandra Snow, medical director of communicable diseases, and Dr. Haytham Safi, senior epidemiologist, both of the Health Department, said the recent mass flu vaccination effort in Arkansas could be behind the high number of flu searches from Arkansas on Google.

"We just finished doing our mass clinic, with over 108,000 people getting the flu vaccine. It's very possible that while we were doing this, people were looking up (sites related to the) flu on Google," Snow said.

The vaccination effort drew news coverage in print, broadcast and Internet media across the state as the Health Department worked to publicize the times and locations of the various places people could get their shots. The vaccine was given in at least one location in each of the state's 75 counties.

Snow said the state is seeing respiratory viruses that make patients uncomfortable for a couple of days, but nothing like the agony and potentially deadly complications brought on by the flu.

The physicians said there is no harm in Google tracking its numbers, but Snow and Safi suggest checking the CDC's Web site for hard data on the flu. The Arkansas Health Department has a large network of doctors, hospitals, schools and clinics that report on flu instances. That information is provided to the CDC and used in its weekly national influenza assessment.

"We have a really good surveillance system in this state," Snow said. "No flu cases have been confirmed yet."

Ed Barham, spokesman for the Health Department, said he hopes that if the Google flu trend site gains a place in the public eye it inspires people to get a flu shot and take other steps to avoid contracting or spreading the illness, such as frequent hand washing and covering a cough.

But Barham also cautioned, "What if we did have flu and the search engine said we didn't?"

The flu is a respiratory illness that brings fever, severe headache, body aches, cough and sometimes stomach upset. It is of particular risk to the very young and older people, though people with certain health conditions are also more vulnerable.

Safi said a potential problem with people relying on the Google site, particularly now, is that some may be inspired to not get their flu shots if they think the flu has already made it to Arkansas. In any case, that would be a mistake, he said.

It takes about two weeks for the flu vaccine to become fully effective and health officials are urging people to get vaccinated. The CDC is planning a National Influenza Vaccination Week, Dec. 8-14. Flu season tends to peak in February.

If someone contracts the virus, the CDC says seeing a doctor and getting a prescription for an antiviral drug within a day or two of the onset can lessen symptoms and lead to a quicker recovery.

The mix in this year's vaccine protects against two Type A-Brisbane viruses and one Type B-Florida virus. So far, flu that has been found in the U.S. has been antigenically similar to the types protected by the vaccine, but the CDC says it is too early to say whether those will indeed be the dominant strains this flu season. Last flu season, officials guessed wrong, though people who got flu shots tended to have milder illnesses when they got infected.