Research Article: Changes in childhood vaccination coverage over time in the Democratic Republic of the Congo

Date Published: May 24, 2019

Publisher: Public Library of Science

Author(s): Vivian H. Alfonso, Anna Bratcher, Hayley Ashbaugh, Reena Doshi, Adva Gadoth, Nicole Hoff, Patrick Mukadi, Angie Ghanem, Alvan Cheng, Sue Gerber, Guillaume Ngoie Mwamba, Jean Jacques Muyembe Tamfum, Emile Okitolonda Wemakoy, Anne W. Rimoin, Italo Francesco Angelillo.

http://doi.org/10.1371/journal.pone.0217426

Abstract

Despite increased vaccination rates, the burden, morbidity and mortality associated with vaccine preventable diseases remains high. In the Democratic Republic of the Congo (DRC), potentially unreliable data and geographically varied program provision call for a better understanding of vaccination coverage and its changes over time at the country and province level. To assess changes in the proportion of children who were fully vaccinated over time in the DRC, vaccination histories for children 12–59 months of age were obtained from both the 2007 and 2013–2014 Demographic and Health Surveys (DHS). Changes were assessed, both at the country- and province-levels, to identify potential geographic variations. Vaccination coverage improved 70% between the DHS waves: 26% compared to 44% of 12–59 month-old children met full vaccination criteria in 2007 and 2013–2014, respectively (n2007 = 3032 and n2013-14 = 6619). Similarly, there was an overall trend across both DHS waves where as year of birth increased, so did vaccination coverage. There was geographic variation in immunization changes with most central and eastern provinces increasing in coverage and most northern, western and southern provinces having decreased vaccination coverage at the second time point. Using nationally representative data, we identified significant changes over time in vaccination coverage which may help to inform future policy, interventions and research to improve vaccination rates among children in the DRC. This study is the first of its kind for the population of DRC and provides an important initial step towards better understanding trends in vaccination coverage over time.

Partial Text

Vaccinations are one of the most efficient and cost-effective public health interventions, resulting in significant reductions in global child morbidity and mortality over the past five decades [1,2]. Child deaths, due largely to infectious diseases, dropped from 12.7 million in 1990 to 5.9 million in 2015 [3], and it is estimated that two to three million child deaths are averted each year due to vaccination [4]. Despite such improvements in global immunization coverage, the burden of vaccine preventable diseases (VPDs) remains high in low- and middle-income countries: VPDs are responsible for 1.5 million preventable deaths in children under the age of five [4] and approximately 29% of deaths among children one to 59 months of age [5]. The 2005 Global Immunization Vision and Strategy set the goal for all countries to meet and sustain 90% national of diphtheria-tetanus-pertussis (DTP3) coverage by 2015 [6]. However, by 2017, 19.9 million children were not fully vaccinated with DTP3 and the majority lived in 10 countries: the Democratic Republic of the Congo, Afghanistan, Angola, Ethiopia, India, Indonesia, Iraq, Nigeria, Pakistan and South Africa [4].

Among children 12–59 months of age, significant increases in BCG, OPV1-3, DTP1-3, measles, and yellow fever vaccinations were observed between the 2007 and 2013–2014 surveys (Table 2). As a result, the proportion of children who were fully vaccinated significantly increased between the two waves from 26% in 2007 to 44% in 2013–2014 (p < .0001). The percentage of children with no vaccinations decreased by 59% between the two surveys (17% in 2007 to 7% in 2013–2014, p < .0001). Additionally, vaccination card ownership changed over time; while the same proportion of biological mothers presented their children’s vaccination card during the two survey waves, reported ownership of vaccination card decreased from 2007 to 2013–2014 (61% and 51%, respectively, p = .001). Similar estimates of vaccination coverage was observed when the sample was restricted to 12–23 month-olds (S1 Table). In this analysis of health survey data from DHS 2007 and 2013–2014, we assessed changes in vaccination status among young children between 12 and 59 months of age in the DRC. Overall, improvements in vaccination coverage were observed over time: 26% compared to 44% of 12 to 59 month-olds were fully vaccinated in 2007 and 2013–2014, respectively. The biggest gains in coverage of individual vaccines were seen in OPV1-3, from 47% in 2007 to 66% in 2013–2014, and yellow fever, from 53% in 2007 to 70% in 2013–2014. This coverage is higher than some other developing nations such as Nigeria, where 23% of children were fully vaccinated in 2016 [32], but comparable to others such as India, where 43% of children were fully vaccinated in 2016 [33].   Source: http://doi.org/10.1371/journal.pone.0217426