Antecedent causes of a measles resurgence in the Democratic Republic of the Congo

Introduction: Despite accelerated measles control efforts, a massive measles resurgence occurred in the Democratic Republic of the Congo (DRC) starting in mid-2010, prompting an investigation into likely causes. Methods: We conducted a descriptive epidemiological analysis using measles immunization and surveillance data to understand the causes of the measles resurgence and to develop recommendations for elimination efforts in DRC. Results: During 2004-2012, performance indicator targets for case-based surveillance and routine measles vaccination were not met. Estimated coverage with the routine first dose of measles-containing vaccine (MCV1) increased from 57% to 73%. Phased supplementaryimmunization activities (SIAs) were conducted starting in 2002, in some cases with sub-optimal coverage (≤95%). In 2010, SIAs in five of 11 provinces were not implemented as planned, resulting in a prolonged interval between SIAs, and a missed birth cohort in one province. During July 1, 2010-December 30, 2012, high measles attack rates (>100 cases per 100,000 population) occurred in provinces that had estimated MCV1 coverage lower than the national estimate and did not implement planned 2010 SIAs. The majority of confirmed case-patients were aged <10 years (87%) and unvaccinated or with unknown vaccination status (75%). Surveillance detected two genotype B3 and one genotype B2 measlesvirus strains that were previously identified in the region. Conclusion: The resurgence was likely caused by an accumulation of unvaccinated, measles-susceptible children due to low MCV1 coverage and suboptimal SIA implementation. To achieve the regional goal of measles elimination by 2020, efforts are needed in DRC to improve case-based surveillance and increase two-dose measles vaccination coverage through routine services and SIAs.Keywords: Measles, outbreak, elimination, immunization, vaccination, surveillance, DRC, RD

Cholera ante portas - The re-emergence of cholera in Kinshasa after a ten-year hiatus.

International audienceBackground: Cholera is an endemic disease in certain well-defined areas in the east of the Democratic Republic of Congo (DRC). The west of the country, including the mega-city Kinshasa, has been free of cases since mid 2001 when the last outbreak ended. Methods and Findings: We used routinely collected passive surveillance data to construct epidemic curves of the cholera cases and map the spatio-temporal progress of the disease during the first 47 weeks of 2011. We compared the spatial distribution of disease spread to that which occurred in the last cholera epidemic in Kinshasa between 1996 and 2001. To better understand previous determinants of cholera spread in this region, we conducted a correlation analysis to assess the impact of rainfall on weekly health zone cholera case counts between December 1998 and March 2001 and a Generalized Linear Model (GLM) regression analysis to identify factors that have been associated with the most vulnerable health zones within Kinshasa between October 1998 and June 1999. In February 2011, cholera reemerged in a region surrounding Kisangani and gradually spread westwards following the course of the Congo River to Kinshasa, home to 10 million people. Ten sampled isolates were confirmed to be Vibrio cholerae O1, biotype El Tor, serotype Inaba, resistant to trimethoprim-sulfa, furazolidone, nalidixic acid, sulfisoxaole, and streptomycin, and intermediate resistant to Chloramphenicol. An analysis of a previous outbreak in Kinshasa shows that rainfall was correlated with case counts and that health zone population densities as well as fishing and trade activities were predictors of case counts. CONCLUSION: Cholera is particularly difficult to tackle in the DRC. Given the duration of the rainy season and increased riverine traffic from the eastern provinces in late 2011, we expect further increases in cholera in the coming months and especially within the mega-city Kinshasa. We urge all partners involved in the response to remain alert.Didier Bompangue and Silvan Vesenbeckh contributed equally to this work. *corresponding author: Silvan Vesenbeckh, Harvard School of Public Health ([email protected])Didier Bompangue is Associate Professor in the Department of Microbiology (University of Kinshasa) andEpidemiologist in the DRC Ministry of Health. He was involved in the investigations of the described outbreak since February 2011

Dynamics of Cholera Outbreaks in Great Lakes Region of Africa, 1978–2008

Outbreaks fluctuate on the basis of season, rainfall, plankton bloom, and fishing activities

Sabre tibia deformity (tertiary lesions) observed during yaws outbreak, rural Wasolo health zone, Equator province, Democratic Republic of the Congo, February 2005 (picture taken by Laurent Ferradini).

<p>Sabre tibia deformity (tertiary lesions) observed during yaws outbreak, rural Wasolo health zone, Equator province, Democratic Republic of the Congo, February 2005 (picture taken by Laurent Ferradini).</p

Primary ulcer lesion observed during yaws outbreak, rural Wasolo health zone, Equator province, Democratic Republic of the Congo, February 2005 (picture taken by Laurent Ferradini).

<p>Primary ulcer lesion observed during yaws outbreak, rural Wasolo health zone, Equator province, Democratic Republic of the Congo, February 2005 (picture taken by Laurent Ferradini).</p

Geographical distributions of active yaw cases per lot and classification of yaws prevalence, rural Wasolo health zone, Equator province, Democratic Republic of the Congo, February 2005.

<p>Geographical distributions of active yaw cases per lot and classification of yaws prevalence, rural Wasolo health zone, Equator province, Democratic Republic of the Congo, February 2005.</p

Distribution of active yaw cases per lot and classification of yaws prevalence, rural Wasolo health zone, Equator province, Democratic Republic of the Congo, February 2005.

*<p>Diagnosed clinically.</p>†<p>Rapid Plasma Reagin test.</p>‡<p><i>Treponema pallidum</i> hemagglutination test.</p>§<p>TMT (total mass treatment); JMT (juvenile mass treatment, treatment of active cases, their direct contacts and all children under 15 years); SMT (selective mass treatment, treatment of both active cases and direct contacts).</p

Papilloma secondary lesion with polydactilitis observed during yaws outbreak, rural Wasolo health zone, Equator province, Democratic Republic of the Congo, February 2005 (picture taken by Laurent Ferradini).

<p>Papilloma secondary lesion with polydactilitis observed during yaws outbreak, rural Wasolo health zone, Equator province, Democratic Republic of the Congo, February 2005 (picture taken by Laurent Ferradini).</p