Date Published: March 20, 2019
Publisher: Public Library of Science
Author(s): Alain Farra, Tuspin Nicephore Loumandet, Marilou Pagonendji, Alexandre Manirakiza, Casimir Manengu, Raphaël Mbaïlao, Severin Ndjapou, Alain Lefaou, Ionela Gouandjika-Vasilache, Olalekan Uthman.
Measles remains a major public health problem in many developing countries in which vaccination coverage is poor, as is the case in the Central African Republic (CAR). At the beginning of the 2000s, a surveillance system was established in the country, and samples from suspected cases are regularly tested in the laboratory for serological confirmation. Since 2007, when case-by-case monitoring with standardized laboratory databases and monitoring, was set up, no assessment have been performed. Therfore, 9 years later it seemed appropriate to make a first assessment. The aim of the study reported here was to describe the epidemiology of measles in the CAR on the basis of surveillance and laboratory data.
A descriptive retrospective study was conducted, based on the databases of the measles surveillance programme and of the Institut Pasteur laboratory in Bangui during the period 2007–2015.
During this study period, the surveillance programme notified 3767 cases. Of these, 2795 (75%) were sent for laboratory confirmation, and 24.6% (687/2795) were confirmed serologically. Of the 1797 cases of measles declared during this period by the surveillance programme, 1110 (61.8%) were confirmed clinically or by epidemiological linkage. The majority of confirmed cases (83.7%; 575/687) occurred in children under 10 years, over half of whom (44.2%; 304/687) were aged 1–4 years. Epidemics occurred regularly between 2011 and 2015, with > 10% of laboratory-confirmed cases. The rate of laboratory investigation was < 80% between 2011 and 2013 but nearly 100% in the other years. Measles remains a common, endemic illness in the CAR. Improved detection will require better measles surveillance, increased vaccination coverage, revision of the investigation forms to include the WHO case definition and training of the health personnel involved in case-finding in the field.
Measles is a highly contagious eruptive viral diseases that occurs only in humans. In 1980, before vaccination became widespread, there were estimated to be 2.6 million deaths due to measles per year . The discovery towards the end of the 1960s of an anti-measles vaccine and its widespread use reduced the morbidity and mortality from this disease considerably. Between 2000 and 2014, 17.1 million deaths were avoided globally, making this vaccine the best public health investment to date . According to the World Health Organization (WHO) Regional Office for Africa, the number of deaths from measles was also considerably reduced in the African Region, from a mean of one million cases per year between 1980 and 1989 to fewer than 100 000 cases per year between 2006 and 2009 . This was due to improved vaccination coverage, from 56% to 69%, an increase from 4 to 13 in the number of countries with vaccine coverage > 90% and a decrease from 8 to 2 in the number of countries with vaccine coverage < 50% . This study was possible thanks to the measles surveillance system set up in CAR which covers the entire territory. Surveillance in health regions has made it possible to collect all suspected cases of measles, as defined by WHO. Although clinical information was limited to the presence of rash, in the laboratory, the techniques were used in accordance with WHO recommendations and the results obtained can be considered reliable because they meet the requirements of the WHO performance indicators and are regularly evaluated. Measles remains a common, endemic illness in the CAR because of inadequate vaccination coverage. In this study, only 24.6% of reported cases were confirmed in the laboratory. Children under 10 years were most affected, with no difference between the sexes. The disease is seen most often during the dry season, with a peak in February, and most confirmed cases were reported from health district 3, which includes Bangui and its suburbs. Better control of measles in the CAR will require increased vaccination coverage, revision of the investigation forms to include the current WHO case definition and training of health personnel involved in case-finding in the field. Source: http://doi.org/10.1371/journal.pone.0213735