Mumps outbreak in the former Yugoslav Republic of Macedonia, January 2008 – June 2009: epidemiology and control measures

Mumps is a mandatorily notifiable disease in the former Yugoslav Republic of Macedonia. Routine vaccination with one dose of measles-mumps-rubella (MMR) vaccine at the age of 13 months started in 1983 and a two-dose vaccination schedule, with the second dose at the age of seven years, was implemented in 1997. The previous mumps outbreak in the country was reported in 1996, with 4,321 registered cases. In October 2007, an increase in mumps notifications was observed. Between January 2008 and June 2009, the Institute of Public Health received 16,352 notifications of mumps cases through the routine surveillance system. Young people aged 15-19 years (n=7,876, 48.2%) were most affected; more males (61.2%, n=10,013) were reported than females. Of the cases whose vaccination status was checked (n=14,178, 86.7%), 19.5% had not been vaccinated, 37% had been vaccinated with one MMR dose, 34.4% had received two doses, 0.6% had been vaccinated during catch-up vaccination (with MMR vaccine for people aged 15-26 years) and for 8.5% there were no records of vaccination. For 13.3% (n=2,174) of reported cases, their vaccination status was not checked. In February 2009, biological specimens (serum, saliva and urine) from 20 cases aged 15-19 years were sent to the National Institute for Public Health and the Environment (RIVM) in the Netherlands for genotyping. Of the 20, nine had been vaccinated with two doses of MMR vaccine, five with one dose, one had not been vaccinated and five had no records of vaccination). Mumps viral RNA was detected in samples from 17 patients: the sequence of the amplified small hydrophobic gene from all 17 showed that the mumps virus was genotype G5. .