Suchergebnisse

Early March 2019, health authorities of Matadi in the Democratic Republic of the Congo alerted a sudden increase in acute fever/arthralgia cases, prompting an outbreak investigation. We collected surveillance data, clinical data, and laboratory specimens from clinical suspects (for CHIKV-PCR/ELISA, malaria RDT), semi-structured interviews with patients/caregivers about perceptions and health seeking behavior, and mosquito sampling (adult/larvae) for CHIKV-PCR and estimation of infestation levels. The investigations confirmed a large CHIKV outbreak that lasted February–June 2019. The total caseload remained unknown due to a lack of systematic surveillance, but one of the two health zones of Matadi notified 2686 suspects. Of the clinical suspects we investigated (n = 220), 83.2% were CHIKV-PCR or IgM positive (acute infection). One patient had an isolated IgG-positive result (while PCR/IgM negative), suggestive of past infection. In total, 15% had acute CHIKV and malaria. Most adult mosquitoes and larvae (>95%) were Aedes albopictus. High infestation levels were noted. CHIKV was detected in 6/11 adult mosquito pools, and in 2/15 of the larvae pools. This latter and the fact that 2/6 of the CHIKV-positive adult pools contained only males suggests transovarial transmission. Interviews revealed that healthcare seeking shifted quickly toward the informal sector and self-medication. Caregivers reported difficulties to differentiate CHIKV, malaria, and other infectious diseases resulting in polypharmacy and high out-of-pocket expenditure. We confirmed a first major CHIKV outbreak in Matadi, with main vector Aedes albopictus. The health sector was ill-prepared for the information, surveillance, and treatment needs for such an explosive outbreak in a CHIKV-naïve population. Better surveillance systems (national level/sentinel sites) and point-of-care diagnostics for arboviruses are needed.

On August 1, 2018, the Democratic Republic of the Congo declared its tenth Ebola virus disease outbreak. To aid the epidemiologic response, the Institut National de Recherche Biomédicale implemented an end-to-end genomic surveillance system, including sequencing, bioinformatic analysis, and dissemination of genomic epidemiologic results to frontline public health workers. We report 744 new genomes sampled between July 27, 2018 and April 27, 2020 generated by this surveillance effort. Together with previously available sequence data (n = 48 genomes), these data represent almost 24% of all laboratory-confirmed Ebola virus infections in DRC in the analyzed period. We inferred spatiotemporal transmission dynamics from the genomic data as new sequences were generated and disseminated the results to support epidemiologic response efforts. Here, we provide an overview of how this genomic surveillance system functioned, present a full phylodynamic analysis of 792 Ebola genomes from the Nord Kivu outbreak, and discuss how the genomic surveillance data informed response efforts and public health decision-making.

During the 2018-2020 Nord Kivu Ebola virus disease (EVD) outbreak in the Democratic Republic of the Congo, an individual who had received the Merck rVSV-ZEBOV vaccine was diagnosed with EVD. His treatment included an Ebola virus-specific monoclonal antibody (mAb114), and he recovered within 14 days but re-presented six months later with severe EVD-like illness and Ebola virus viremia and died. We initiated an epidemiological and genomic investigation that showed the patient had a relapse of acute EVD, which led to a transmission chain that resulted in 91 cases spanning six health zones over four-months.