Four cases of the mumps have been confirmed in Denver with two more probable cases under investigation, according to The Denver Post.
"We usually see about 2.5 cases per year (in the city)," Heather Young, MD, an epidemiologist at Denver Health Medical Center, told the Post. "This is certainly an increase over what we would usually see."
Investigators believe the cases are linked to a mumps outbreak in Iowa. The initial carrier is thought to be someone who recently moved from Iowa to Colorado who then infected three friends. The Colorado Department of Public Health Environment says three healthcare workers contracted the mumps virus while treating the infected patients. The workers had previously been vaccinated. It is known that the effectiveness of the vaccine can lessen as adult immunity diminishes with age.
The CDPHE issued a warning on Tuesday for physicians and nurses statewide to be on the lookout for additional cases.
Mump outbreaks have been reported this year at three Indiana universities and the University of Kentucky in Lexington. In August 2015, nearly 100 cases of mumps were reported at the University of Illinois at Urbana-Champaign.
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