Accelerating Vaccine Development During the 2013–2016 West African Ebola Virus Disease Outbreak

Abstract

The Ebola virus disease outbreak that began in Western Africa in December 2013 was unprecedented in both scope and spread, and the global response was slower and less coherent than was optimal given the scale and pace of the epidemic. Past experience with limited localized outbreaks, lack of licensed medical countermeasures, reluctance by first responders to direct scarce resources to clinical research, community resistance to outside interventions, and lack of local infrastructure were among the factors delaying clinical research during the outbreak. Despite these hurdles, the global health community succeeded in accelerating Ebola virus vaccine development, in a 5-month interval initiating phase I trials in humans in September 2014 and initiating phase II/III trails in February 2015. Each of the three Ebola virus disease-affected countries, Sierra Leone, Guinea, and Liberia, conducted a phase II/III Ebola virus vaccine trial. Only one of these trials evaluating recombinant vesicular stomatitis virus expressing Ebola virus glycoprotein demonstrated vaccine efficacy using an innovative mobile ring vaccination trial design based on a ring vaccination strategy responsible for eradicating smallpox that reached areas of new outbreaks. Thoughtful and intensive community engagement in each country enabled the critical community partnership and acceptance of the phase II/III in each country. Due to the delayed clinical trial initiation, relative to the epidemiologic peak of the outbreak in the three countries, vaccine interventions may or may not have played a major role in bringing the epidemic under control. Having demonstrated that clinical trials can be performed during a large outbreak, the global research community can now build on the experience to implement trials more rapidly and efficiently in future outbreaks. Incorporating clinical research needs into planning for future health emergencies and understanding what kind of trial designs is needed for reliable results in an epidemic of limited duration should improve global response to future infectious disease outbreaks.

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“…Pharmacists are a critical part of healthcare systems, carrying out gorgeous title roles in the untimely pandemics and health crises, with some like Ebola and Zika creating world health collateral perils also. Likewise, by using pitching-in in the avoidance, alertness, discovery, and feedback to COVID-19 pandemic pharmacists and pharmaceutical scientists are conveying their responsibility towards public fitness in consideration of this disaster [35][36][37] . In various countries, pharmacies have worked in immediate cooperation with the International humanitarian agencies like the Red Cross and native company employees to extend their reach to the public and to ensure domestic consignment of medicaments 38 -39 .…”

Missed vaccinations and critical care admission: all you may wish to know or rediscover—a narrative review

“…First identified in the 1970s, Ebola viruses are responsible for a frequently-fatal haemorrhagic fever disease. Their spread from Central to Western Africa led to a devastating outbreak between 2013 and 2016 [50]. Although initially delayed, the response strategy of the health community-integrated Phase I vaccination trials at an unprecedented pace.…”

“…This successful experience demonstrated how research can be accelerated in short delays when adequately supported/funded and appropriately championed. It also showed that clinical trials can be rapidly performed during outbreaks and could play a critical role in ending ongoing epidemics [50]. However, the use of rVSV-ZEBOV in response to a new epidemic that emerged in Democratic Republic of Congo at the end of 2017 and is not yet under control in September 2019 reminds us that even the most potent vaccines (> 97% estimated efficacy) must be administered timely to be effective [53].…”

High dose of vesicular stomatitis virus-vectored Ebola virus vaccine causes vesicular disease in swine without horizontal transmission

“…EVD is caused by the highly pathogenic Ebola virus (EBOV), a member of the Filoviridae family [2]. The 2013-16 west-African Ebola virus epidemic was the largest outbreak ever recorded, with over 28,000 cases and 11,000 deaths, and exposed an urgent need for vaccination strategies to control future outbreaks [3,4]. The outbreak prompted the progression of a promising Vesicular Stomatitis Virus (VSV)vectored Ebola virus vaccine (designated V920, VSV-EBOV) through clinical trials [5][6][7][8][9][10][11].…”