Booster doses of COVID-19 vaccine: Rationales, implications and way forward for African countries

Abstract

To contain a pandemic, access to an effective and safe vaccine is a global public health necessity. However, an effective and safe vaccine will not protect against a disease, unless it is given to susceptible persons in the proper dosage and in a timely manner. Since the commencement of the Coronavirus pandemic, every country has been attempting to develop or obtain a vaccine to safeguard their citizens. Because many developing countries, particularly those in Africa, lack the technological capacity to manufacture vaccines, their best option is to purchase one. As a result, many African countries have been able to obtain the initial dose of COVID-19 vaccines, but obtaining the booster doses has proven difficult for many. For multiple-dose vaccines, the interval between doses is crucial to reaping the full advantages of any specific vaccine. At the moment, public health officials are afraid that delay in receiving booster doses will allow the coronavirus to outsmart immunization efforts. While some argue that delaying booster doses will allow host immunity to wane, potentially leading to the emergence of a new, more contagious variant of concern (VOC) that may defeat the vaccine and grounds already conquered, others argue that up to 3 months between doses of two approved vaccines should be allowed instead of the one month studied in vaccine clinical trials. In ananxious attempt to stem the massive increase in confirmed cases and to prevent the spread of a new, more contagious variant of the virus, the highly developed and rich countries have continued to make concerted efforts to get as many people as possible vaccinated with multiple number of doses, without considering the poor COVID-19 vaccine supply chain or the fragile health systems of resource-limited countries like those in Africa. The purpose of this review is to look at the rationales for COVID-19 vaccine booster doses, supply chain bottlenecks, implications and recommendations for African countries.