FRIDAY, Oct. 10 (HealthDay News) -- The U.S. Centers for Disease Control and Prevention, the Healthcare Infection Control Practices Advisory Committee and the American Academy of Pediatrics (AAP) have all revised their isolation guidance for mumps patients down from nine days to five days after onset of parotitis, according to a report published in the Oct. 10 issue of the CDC's Morbidity and Mortality Weekly Report.
The AAP and the CDC re-examined the evidence in support of the nine-day isolation period recommendation by reviewing eight small studies with a median 16 subjects, which compiled data on viral isolation from saliva or throat swabs.
The data revealed that whereas 81 percent of samples tested positive for mumps virus one day after onset of parotitis, this declined to 49 percent after two to three days, 40 percent after four to five days, and 17 percent after six to seven days.
"The scientific evidence from the CDC and AAP review indicates that, although mumps virus can be isolated from saliva or respiratory secretions five or more days after parotitis onset, virus most often is isolated before or around the time of onset, and viral load decreases rapidly during the four days after onset of parotitis," the report states. "Therefore, the risk for transmission after five days is considered low."