Eliminating Measles: Contributions by the Oporto International Vaccination Centre from 2017 to 2018

Abstract Background Measles is one of world's most contagious diseases and a growing population mobility has promoted its spreading. Outbreaks have been recorded around the world, despite public health efforts. Measles spreads faster among clusters of unvaccinated people. In 2018, World Health Organization reported 328629 cases worldwide, of which 82596 in Europe and 171 in Portugal- 93% of the latter were imported. Portugal had one of the highest proportions of childhood immunization coverage for Measles-Mumps-Rubella (MMR): 98% for first dose, and 96-98% for second. The main goal of this study was to describe the contribution of the Oporto International Vaccination Centre (OIVC), one of the largest in Portugal, to measles elimination. Methods Cross-sectional study, with analysis of vaccination records from travelers vaccinated for MMR at OIVC between January 2017 and December 2018. Results OIVC held 5426 pre-travel consultations in 2017, and 6192 in 2018. 535 travelers got the MMR vaccine (57.2% males). Mean age was 44.3±10.9 [1;76] years. Among travelers aged 12 months-18 years (n = 10), 50% were inoculated with the first dose and 50% with the second. Regarding adult travelers (n = 525), 71.6% received the first dose; 24.2% the second; 2.9% the third dose; and 1.3% received both first and second (within > 4 weeks). Conclusions The substantial number of inoculated vaccines in OIVC resulted from checking traveler's vaccination immunity status in all pre-travel consultations; this routine practice aimed at reducing the risk of importing/exporting measles. The second dose of MMR was justified by the diversity of travelers who came to OIVC, and to whom such inoculation was indicated: health professionals, humanitarian travelers, and workers in airlines and cruises. The third dose was given due to loss of measles serologic immunity. These measures are important to implement the recommendations of the Measles National Elimination Program, while contributing to global public health. Key messages This is an original study on the contribution of international vaccination centers to reduce the number of imported/exported cases and to eliminate measles - which is a global public health issue. At a global level, measles has a large disease burden. Therefore, it is essential to take every opportunity, including pre-travel consultations, to vaccinate people.