Vaccinating against monkeypox in the Democratic Republic of the Congo

Abstract

Healthcare-associated transmission of monkeypox has been observed on multiple occasions in areas where the disease is endemic. Data collected by the US Centers for Disease Control and Prevention (CDC) from an ongoing CDC-supported program of enhanced surveillance in the Tshuapa Province of the Democratic Republic of the Congo, where the annual incidence of human monkeypox is estimated to be 3.5-5/10,000, suggests that there is approximately one healthcare worker infection for every 100 confirmed monkeypox cases. Herein, we describe a study that commenced in February 2017, the intent of which is to evaluate the effectiveness, immunogenicity, and safety of a third-generation smallpox vaccine, IMVAMUNE^®, in healthcare personnel at risk of monkeypox virus (MPXV) infection. We describe procedures for documenting exposures to monkeypox virus infection in study participants, and outline lessons learned that may be of relevance for studies of other investigational medical countermeasures in hard to reach, under-resourced populations.

Keywords: Clinical trial; Democratic Republic of the Congo; IMVAMUNE; Monkeypox; Smallpox vaccine.

Fig. 1

(A) Suspect monkeypox case notifications and deaths in the DRC from 1996 to 2016. Cases are often not followed to outcome; thus, this does not represent a fatality rate. (B) Distribution of monkeypox cases and deaths in the DRC from 1996 to 2015 (Nakazawa et al., 2013).

Fig. 2

Countries that have reported cases of human MPX, including those that have sent samples to the INRB Laboratory in Kinshasa for diagnostic testing from 2007 to 2017.

Fig. 3

IMVAMUNE vaccine study. (A) Prospective participant reviewing study consent documents with local study coordinator. (B) Serum collection prior to vaccination. (C) Vaccination of the first participant in the study.