MADISON, Wis. -- Public Health Madison and Dane County on Tuesday said the first probable case of the swine flu has been identified in Madison. But the state Department of Health Services isn't yet calling the case probable and said it is "under investigation."

Dr. Tom Schlenker, the director of Public Health Madison and Dane County, said the case is a 5-year-old Madison boy who became ill while visiting Mexico and is suspected of having the so-called swine flu, or H1N1 virus.

Schlenker said the boy returned in late April from visiting Mexico for three months. Schlenker said the boy saw a doctor in Mexico before returning to Madison. Once he returned, his parents took him to his family doctor in Madison after his symptoms of coughing, sore throat and body aches continued, Schlenker said.

Health officials said the boy is isolated and continues to rest at home with his parents, who didn't go with him to Mexico. Schlenker said the boy is now fully recovered.

"He didn't need any treatment. He got better on his own, as most everybody will with influenza," Schlenker said.

Health officials said the entire family remains in isolation at home and is being monitored daily by Public Health Madison and Dane County.

Schlenker said he will not ask the Madison Metropolitan School District to close any schools because the boy did not attend school for three months.

Seth Boffeli, spokesman for the Wisconsin Department of Health Services, said they typically run two tests for the swine flu virus. He said this case did test positive for the Influenza A strain of H1N1, but that a second test to determine if this strain matches with any other current flu strains is not back yet. Boffeli said that's the reason the state is currently considering the Madison case as "under investigation" for swine flu and not a probable case.

State Public Health Officer Dr. Seth Foldy told the Assembly's Public Health Committee on Tuesday that the number of cases confirmed has gone up from three to five.

A Department of Health Services spokesman said the U.S. Centers for Disease Control and Prevention have confirmed positive cases in Ozaukee and Sheboygan counties of the H1N1 virus. There were two previously confirmed cases in Milwaukee County and one in Adams County.

University of Wisconsin, state and county health officials presented the latest information on the flu outbreak to the Assembly committee Tuesday. They shared their response to the virus and anticipated challenges as the virus moves on.

"It is now reasonable to say this is a virus that is well-established and fairly widespread in the Wisconsin population. Those that we have positive tests for are probably the tip of the iceberg," Foldy said.

Rock County health officials noted how stretched their staff and budgets were while dealing with the virus.

But the state and infectious disease specialists said Tuesday that the H1N1 virus might not be as contagious or as serious as expected.

"It's very plausible, at least I think, that this strain is no more virulent, or if it is it's not a huge amount more virulent, than the seasonal influenza we've been seeing," said Dr. Dennis Maki, an infectious Disease expert at the UW-Madison Medical School. "Does that mean we should relax? Absolutely not, because everybody is going to be susceptible and it will come back this fall, I think, with a fury."

Maki said concern lies with who is getting the virus. Currently, he said healthy people are battling the symptoms but things could change if elderly people become ill with the virus. That's why Foldy and Maki said a vaccination needs to be found before the fall and winter flu season.

Health officials are still making efforts to control the spread and treatment of the virus, but they aren't as concerned about it as they once were, WISC-TV reported. They said the question now is how easy it will be for the state to prepare for a possible pandemic in the fall.

Foldy said there are 119 probable cases in Wisconsin, spread across 10 counties, and those likely will get confirmed in coming days.

The CDC said the number of confirmed swine flu cases in the United States is now over 400, with hundreds more probable cases.

Shuttered Milwaukee Schools To Reopen Wednesday

All 17 of the Milwaukee Public Schools that have been closed in the past week due to the outbreak of the flu will reopen Wednesday.

The Milwaukee Health Department announced Tuesday it was reversing an order that would have kept the schools closed through the end of the week.

School and health officials continue to say that any child with flu-like symptoms should be kept home from school or day care for seven days. But events like proms, graduations and sporting events will go on.

There have been five confirmed cases of H1N1 in Wisconsin and many more are expected as probable tests are confirmed. Worldwide, there have been about 1,500 confirmed swine cases of the virus, including more than 400 in the United States.