No swine flu reported in Ga.

No cases of swine flu have been reported in Georgia, but local health officials are keeping a close eye out.

"It doesn't seem to be having the same effect outside of Mexico as in Mexico," said Vernon G. Goins, public information officer of the East Metro Health District that includes Rockdale, Newton and Gwinnett counties. "Maybe there is a weakening of the strain as it spreads; that would be the good news."

The federal government has issued a travel advisory instructing Americans to avoid nonessential travel to Mexico, the acting head of the Centers for Disease Control and Prevention said Monday.

Dr. Richard Besser made the disclosure during a news conference in Atlanta, saying the advisory was being released "out of an abundance of caution."

Besser also reported 40 confirmed cases of swine flu in the United States, including 20 in New York City. He said people can help keep the disease from spreading by taking everyday precautions such as frequent handwashing, covering up coughs and sneezes, and staying away from work or school if they're not feeling well.

So far, the disease in the United States seems less severe than the outbreak in Mexico, where more than 1,600 cases have been reported and where the suspected death toll has climbed to 149, Besser said. No deaths have been reported in the U.S., and only one hospitalization.

"I wouldn't be overly reassured by that," Besser told reporters at CDC's headquarters in Atlanta. He raised the possibility of more severe cases in the United States.

"We are taking it seriously and acting aggressively," Besser said. "Until the outbreak has progressed, you really don't know what it's going to do."

The U.S. stepped up checks of people entering the country by air, land and sea.

Besser said other cases have been reported in the states of Ohio, Kansas, Texas and California. He said that of the 40 cases, only one person has been hospitalized and all have recovered.

There is no vaccine available to prevent the specific strain now being seen, he said. However, there are antiflu drugs that do work once someone is sick.

The East Metro Health District has added a widget to its Web site that people can download and use along with a link to the Swine Flu information page of the Centers for Disease Control and Prevention.

The information can be found at www.rockdalehealth.com and www.newtonhealth.com or by logging in directly to www.cdc.gov/swineflu.