Tetanus seroprotection among children in the Democratic Republic of the Congo, 2013-2014.

BackgroundTetanus is a potentially fatal disease that is preventable through vaccination. While the Democratic Republic of the Congo (DRC) has continued to improve implementing routine vaccination activities throughout the country, they have struggled to maintain high childhood vaccine coverage. This study aims to examine the seroprevalence of tetanus in children 6 to 59 months to identify areas for intervention and improvement of vaccination coverage.MethodsIn collaboration with the 2013-2014 Demographic and Health Survey, we assessed the seroprevalence of tetanus antibodies among children in the DRC. Dried blood spot samples collected from children 6-59 months of age were processed using a prototype DYNEX Multiplier® chemiluminescent automated immunoassay instrument with a multiplex measles, mumps, rubella, varicella and tetanus assay. Multivariable logistic regression was used to determine factors associated with tetanus vaccination and seroprotection.ResultsOverall, 36.1% of children 6-59 months of age reported receiving at least 1 dose of tetanus vaccine while 28.7% reported receiving 3 doses; tetanus seroprotection was 40%. Increasing age in children was associated with decreased tetanus seroprotection, but increased number tetanus vaccinations received. Factors related to increased tetanus seroprotection included number of children in the household, wealth index of the family, urban residence compared to rural, level of maternal education, and province and geography.ConclusionsOur findings in this nationally representative sample indicate that serology biomarkers may help identify children who are not fully immunized to tetanus more accurately than reported vaccination. While children may be captured for routine immunization activities, as children age, decreasing seroprevalence may indicate additional need to bolster routine vaccination activities and documentation of vaccination in school aged children. Additionally, the study highlights gaps in rural residential areas and vaccination coverage based on maternal education, indicating that policies targeting maternal education and awareness could improve the coverage and seroprevalence of tetanus antibodies in the DRC

Pan-ebolavirus serology study of healthcare workers in the Mbandaka Health Region, Democratic Republic of the Congo

Although multiple antigenically distinct ebolavirus species can cause human disease, previous serosurveys focused on only Zaire ebolavirus (EBOV). Thus, the extent of reactivity or exposure to other ebolaviruses, and which sociodemographic factors are linked to this seroreactivity, are unclear. We conducted a serosurvey of 539 healthcare workers (HCW) in Mbandaka, Democratic Republic of the Congo, using ELISA-based analysis of serum IgG against EBOV, Sudan ebolavirus (SUDV) and Bundibugyo ebolavirus (BDBV) glycoproteins (GP). We compared seroreactivity to risk factors for viral exposure using univariate and multivariable logistic regression. Seroreactivity against different GPs ranged from 2.2-4.6%. Samples from six individuals reacted to all three species of ebolavirus and 27 samples showed a species-specific IgG response. We find that community health volunteers are more likely to be seroreactive against each antigen than nurses, and in general, that HCWs with indirect patient contact have higher anti-EBOV GP IgG levels than those with direct contact. Seroreactivity against ebolavirus GP may be associated with positions that offer less occupational training and access to PPE. Those individuals with broadly reactive responses may have had multiple ebolavirus exposures or developed cross-reactive antibodies. In contrast, those individuals with species-specific BDBV or SUDV GP seroreactivity may have been exposed to an ebolavirus not previously known to circulate in the region

Identification of the PfK13 mutations R561H and P441L in Democratic Republic of Congo (DRC).

BACKGROUND: Partial artemisinin resistance, mediated by P. falciparum K13 (PfK13) mutations, has been confirmed in certain areas of East Africa which are historically associated with high-level antimalarial resistance. DRC borders these areas in the East. OBJECTIVES: To determine the prevalence of resistance markers in six national malaria control programme (NMCP) surveillance sites; Boende, Kabondo, Kapolowe, Kimpese, Mikalayi and Rutshuru. METHODS: The SNPs in P. falciparum genes PfK13, Pfdhfr, Pfdhps, Pfmdr1 and Pfcrt were assessed using targeted NGS of isolates collected at enrolment in therapeutic efficacy studies. RESULTS: PfK13 SNPs were detected in two samples; in Kabondo (R561H) and in Rutshuru (P441L), both areas near Uganda and Rwanda. The Pfdhps ISGEGA haplotype, associated with reduced SP chemoprevention efficacy, ranged from 0.8% in Mikalayi (central DRC) to 42.2% in Rutshuru (East DRC). CONCLUSIONS: R561H and P441L observed in eastern DRC are a concern, as they are associated with delayed ACT-clearance and candidate marker of resistance, respectively. This is consistent with previous observations of shared drug resistance profiles in parasites of that region with bordering areas of Rwanda and Uganda. The likely circulation of parasites has important implications for the ongoing surveillance of partial artemisinin-resistant P. falciparum and for future efforts to mitigate its dispersal