No cases of swine flu have been reported in St. Francis and Cudahy as of earlier this week.
"But that could change tomorrow," said Cudahy Health Officer Carol Wantuch.
She said swine flu can be easily spread because of a "very mobile" society.
To prevent the virus from spreading, Wantuch has been communicating with staff from various local organizations and businesses, community-based residential facilities, Aurora St. Luke's South Shore hospital and the School District of Cudahy.
While there are no probable cases of the swine flu virus in Cudahy or St. Francis, some suburban health departments have been investigating specific cases, Wantuch said.
One Cudahy resident was tested for swine flu, but it turned out the person had seasonal allergies, Wantuch said.
"We've been lucky so far," she said.
Many people with allergies have some symptoms of swine flu like a fever, Wantuch said.
St. Francis Public Health Officer Kathy Scott said there have been no probable cases reported in St. Francis at this time.
Officials are "keeping a close eye on area schools" for possible outbreaks, Scott said.
Letters about the virus were sent to parents in St. Francis and Cudahy.
Public health officials have also been in contact with local businesses and day-care centers, Scott said.
Wantuch said preventing the novel virus from spreading is important because no one has immunity to it, and infected people are more likely to be sick and develop complications, which could be fatal.
At this time, there is no vaccine for swine flu and there will likely not be one for at least four to six months, Wantuch said.
Chantel Balzell can be reached at (262) 446-6602.
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