Mumps outbreak in a highly vaccinated population-implication for public health policy

Background

In Bahrain, following the introduction of routine infant measles-mumps-rubella (MMR) vaccination in 1985, and the addition of a second routine dose of MMR vaccine in 1998, mumps became uncommon disease in Bahrain. The average incidence of mumps in Bahrain for the period 2001-2006 was 5.7 per 100,000 populations. The total mumps cases were 22 in 2006.  

This paper investigates an outbreak of Mumps among military and Police camps occurs in September 2007 and the implication for vaccination policy in Bahrain.

 Method:
A cluster of mumps cases were reported from Bahrain Defense Force (BDF) hospital and ministry of interior clinic to Diseases control section (DCS) in public health directorate. The total cases were 317 from BDF and 797 from ministry of interior.
 All suspected cases- except two cases from police clinic- were interviewed by public health specialist and the data collected using a standard mumps investigation form used in diseases control section.

The data entry and analysis was undertaken by EPI info program.

 Results
A total of 56 cases were suspected of having mumps of which 25 were from BDF camp & 31 from police academy camp. Out of the 56 only 44 fit the WHO definition of either laboratory confirmed or epidemiologically confirmed mumps cases, of which 24 from BDF camp & 20 from police academy camp. A total of 15 cases were laboratory confirmed of which 9 from BDF and 6 from police.
The incidence rate was 3.9 % for both camps.

 Recommendation
To review the immunization status of all newly recruited personnel in BDF and Police for completion of vaccination and to complete their vaccination.
To strengthen the communicable diseases surveillance among BDF & police camps.