MILWAUKEE -- Health department officials say there are 65 probable cases of swine flu in the state, including a new one in Jefferson County and another in Kenosha County.

 

To date, there are three confirmed cases in the state -- one in Adams County and two in Milwaukee County.  

 

Experts say the outbreak has not hit its peak.

 

More than 20 Milwaukee-area schools have their doors shut for the day, keeping thousands of kids out of the classrooms.
 
In Racine, Kansasville Elementery also closed.

 

St Adalbert's School re-opened Monday, after closing last week due to threats of the swine flu.

 

The Milwaukee health department said there are 60 probable cases of swine flu in the county.

 

University of Wisconsin Medical School Associate Professor Dr. Geoffrey Swain says that number will likely keep going up for at least another week or two.

 

He says the swine flu will keep spreading until enough people develop immunity to break the chain.
 
But he says some people who get swine flu and become immune will get a mild case -- perhaps even milder than originally anticipated.

 

"The swine influenza does appear to be more severe than regular seasonal influenza, but doesn't appear to be as severe here as it was in Mexico," said Dr. Swain, the city health department's medical director.

 

Dr. Swain says that hasn't slowed down researchers hard at work developing a vaccine, hopefully to be ready by fall.
 
The Milwaukee School of Engineering (MSOE) helps in such efforts by creating 3D models of the proteins that distinguish one virus from another.

 

"Knowing the three-dimensional structure of these proteins allows researchers to then hone in on a given area of the protein and develop drugs that will specifically bind to and inhibit the normal structure of that protein," said Tim Herman, Ph.D., director of the center for biomolecular modeling at MSOE.

 

Dr. Swain says a vaccine would be critical if the swine flu turns out to be weak in the spring but returns stronger in the fall, like the Spanish flu did in 1918 when it killed millions.

 

Dr. Swain says so far, only one swine flu victim in Milwaukee has been hospitalized.
 
He says most of the hundreds of suspected cases turned out to be other common viruses and a handful were regular flu. He says about 10% of all suspected cases turn out to be swine flu.

 

"It's so early in the swine influenza outbreak to tell how severe the disease is going to be," said Dr. Swain.

 

He says if experts determine that the swine flu outbreak in the United States  won't be as dangerous as it was in Mexico, then schools will likely re-open.