At least 56 cases of mumps have been reported in Florida in 2017, a significant rise over prior years but well below outbreaks in other states, which have reported hundreds of infections this year.
In Florida, mumps cases have occurred across all ages, with the most infections reported in Broward, Collier, Duval, Hillsborough and Palm Beach counties, according to a Florida Department of Health advisory to physicians dated Dec. 11.
The 2017 count includes confirmed and probable cases, said Brad Dalton, a health department spokesman. Dalton said the health department publishes a monthly surveillance report for mumps and other diseases, though the most current report is for November and counts 54 cases.
Before the U.S. mumps vaccination program started in 1967, about 186,000 cases were reported each year.
Dalton said in an email that the health department recommends vaccination as the most effective way to prevent mumps.
“The Measles, Mumps, Rubella (MMR) vaccine is the best way to prevent all three conditions,” he said.
Yet, in at least half of the cases, the infected person had a documented history of the MMR vaccination, according to the December advisory for physicians.
Florida’s surveillance report notes that mumps cases have been high since April, with a monthly peak of 20 cases reported in August. That trend follows a national pattern for mumps, which has skyrocketed in 2016 and 2017 compared to prior years, according to the Centers for Disease Control and Prevention. Outbreaks have been reported among people in close settings, such as people playing on the same sports team or living in a dormitory with someone who has mumps.
Federal health officials estimate that about 5,000 people have had mumps this year, with the highest numbers reported in Arkansas, Missouri, New York, Texas and Washington state. In 2016, more than 6,000 cases of mumps were reported.
The actual number of cases, however, could be higher, in part because some people who get the disease have very mild or no symptoms, which include fever, headache, muscle aches, tiredness, loss of appetite and swollen and tender salivary glands under the ears — which causes the telltale puffy cheeks and swollen jaw.
Symptoms typically appear 16 to 18 days after infection, but the incubation period for the virus that causes mumps can range from 12 to 25 days. Most people with mumps recover completely in a few weeks.
The virus spreads through contact with an infected person’s saliva or mucus.
Florida’s advisory for physicians said that health officials have investigated small mumps outbreaks among household and other close contacts, and among a group of high-school students and their contacts.
The state’s 2017 count is the highest number of mumps cases for a single year in more than a decade, though infections have risen steadily in recent years, with 10 cases in 2015 and 16 cases in 2016.
High vaccination rates for mumps help limit outbreaks, but even those who are vaccinated can still get the virus, the CDC says. The agency recommends children get two doses of MMR vaccine, which provides 88 percent protection against mumps.