Herb Bostrom, director of the state Bureau of Communicable Diseases, said some people made their decision after reviewing material from the federal Centers for Disease Control and Prevention on possible serious and even deadly side effects.
Meanwhile, the head of the federal Centers for Disease Control says monkeypox, as well as SARS and West Nile Disease, are "the new normal" in health.
"This is the era of emerging infectious diseases," Dr. Julie Gerberding said on CBS News' Early Show Tuesday.
U.S. health authorities must think globally.
"Anything can get into this country," Gerberding said. "We have to think about the whole world as a place where infections emerge. A problem in one corner of the world could very soon be a problem here."
Bostrom did not release figures Monday on how many people who have been in contact with animals or other people infected with monkeypox were eligible for the vaccines. He said "the numbers are very, very small."
About 90 people who were eligible had been told the shots were available at a clinic Saturday, but none came, said Milwaukee's health commissioner, Dr. Seth Foldy.
Monkeypox, a west African disease not previously seen in the Western Hemisphere, is related to smallpox but is not as lethal. It causes rashes, chills and fever.
The vaccinations, offered at the CDC's recommendation, can prevent monkeypox if used within two weeks after exposure. The smallpox vaccine is widely available because states stocked up on it out of fear of bioterrorism.
Officials concede the vaccine is risky. It is made with a live virus that can infect the body. Experts estimate that 15 to 50 people out of every 1 million vaccinated for the first time will face life-threatening complications, and one or two will die.
At least two affected states — Ohio and Illinois — are not offering the smallpox vaccine to possible victims. Ohio has no plans to offer it, officials said, and Illinois hasn't yet made up its mind.
By Monday, state health officials had confirmed at least 15 human cases of the disease in the United States: seven in Wisconsin and four each in Indiana and Illinois. Eighty-two suspected cases had been reported — 22 in Indiana, 34 in Wisconsin, 15 in Illinois, six in Kentucky, two in Ohio, and one each in Arizona, Kansas and Missouri.
Prairie dogs sold as exotic pets are believed to have been infected in an Illinois pet shop by a Gambian giant rat imported from Africa. Federal officials said the prairie dogs may have been sold to buyers in 15 states. The USDA earlier this month banned their sale in the U.S.
"Now that we've taken the steps necessary to prevent their spread throughout the country, we're confident we'll be able to get this under control, at least in the short run," the CDC's Gerberding told CBS News.
No one has died so far from the outbreak, which was first detected last month. At least 14 people with symptoms have been hospitalized, including a child with encephalitis, or brain inflammation, according to the CDC.