Religious visitors (RV) to Makkah, Saudi Arabia, must be vaccinated against meningococcal disease (MCD). In 1997, the surveillance system in Makkah detected increasing cases of MCD among RV during Ramadan, the holy month of fasting for Muslims. We report the extent of the MCD outbreak, the epidemiologic characteristics of MCD cases, and the vaccination coverage with meningococcal vaccine (MCV) among the Makkah population.
Methodology
We reviewed the medical records of all bacteriologically confirmed cases of MCD admitted to Makkah hospitals. We divided Makkah into three geographical zones: immediately around the Haram (the Holy Mosque) within 500 meters, 500 meters to 4 kilometers away from Haram, and more than 4 kilometers from the Haram. We selected 32 random starting points (dwellings) within these zones and seven neighboring houses or apartments. A maximum of ten persons were interviewed in each dwelling to ascertain their vaccination histories.
Results
We identified 51 confirmed cases of MCD from 15 countries (40% were Pakistani). Mean age was 48 years (range: 6-83). Of patients, 71% were RV, 25% were non-Saudi residents, 4% were Saudis. Case fatality rate (CFR) was 27.5% and did not differ with the residency status. Pakistanis accounted for 50% of deaths. From the survey (707 persons), we estimated the coverage with MCV within the last three years to be 75% (95% CI 71%-78%) compared with 29.4% among cases. The MCV vaccine efficacy was 86% (95% CI 73%-93%). Vaccination coverage was 87% (95% CI 79%-93%) for RV, 76% (95% CI 72%-80%) for non-Saudi residents, 70% (95% CI 62%-77%) for Saudi citizens, and 49% (95% CI, 34%-64%) for illegal aliens. Highest vaccination coverage was found in North Africans 86% (95% CI 80%-97%) and lowest among Southeast Asians 57% (95% CI 42%-70%). Vaccination coverage for the three geographical zones around the Haram decreased from 79% (95% CI 74%-84%) in the area that lies within 500 meters from Haram to 69% (95% CI 62%-76%) in the areas four kilometers or more from Haram. The reasons for not being vaccinated included not knowing about the disease (47%), too busy to go to a health center (26%), vaccination not important (8%), and told vaccination would be given in Saudi Arabia (2%). 25% of respondents gave no reason.
Conclusion
The moderately high efficacy of MCV makes it a powerful tool against MCD. To increase coverage all visitors to Makkah need to be educated about the seriousness of the disease and certain nationalities may require special additional efforts.