The whole world is concerned about the vaccine for COVID-19 due to fatality of this condition. On-time vaccination is highly imperative to contain the SARS-CoV-2 pandemic which has been identified to possess a high level of infectivity and high rate of human to human transmission. Traditional public health strategies are currently being employed towards mitigating the virus spread alongside the use of extensive lockdowns in communities and observance of physical distancing. Continuous enforcement of the preventive strategies has been challenging. Moreover, for how long shall the communities remain on lockdown? Experts have stated that the general public will have to live with the pandemic’s social and economic disruption for quite a while. Obviously successful COVID-19 vaccine development is needed as soon as possible. However, vaccine trials are currently on course, yet development of vaccine can take many months to years 13. A vaccine is targeted at boosting natural immune response to an invading virus by priming it to recognize antigens and distinct molecules located on the surface of pathogens. Basically, the response of the immune system is based on the availability of these antigens from the production of special immune cells to directly attack the pathogen, or by the production of proteins named antibodies. Antibodies become attached to an antigen, then become attracted by the immune cells that engulf and destroy the pathogen. Vaccine possesses the ability to usurp herd immunity in communities and territories in a bid to reduce disease incidence, prevent transmission, and lower economic and social burden of the disease. Increased immunization coverage is a potent approach in fighting the pandemic effectively, block secondary infection waves, and mitigate seasonal endemic infection outbursts. Along the way, there could be the eradication of the disease as seen in several past diseases (poliomyelitis, smallpox etc.) with higher potential than COVID-19 to result in pandemic 1415.

Recent efforts by researchers is seen in the continuous monitoring of the genetic sequence of SARS-CoV-2 due to possible rapid mutations so as to acquire crucial data required to assist in providing adequate responses for this current outbreak and that to come in the future. This is very important for the vaccine development studies. Viruses originating from animal species and getting transferred to humans are specifically problematic. They have the capacity to undergo rapid mutations due to their animal origin, for which no preexisting immunity is essentially available in the human population. Interestingly, mutations do not practically affect the functioning of the virus regardless of the fact that mutations within the genome of the virus take place during outbreaks. Such mutations are also unlikely to present any significant resistance to a future vaccine 16.

Vaccine development is a long, tedious and costly process with multiple clinical trials to ensure safety. WHO reports that as at July 2020, they are tracking over 140 vaccine candidates out of which 24 are in the clinical development phase 17. By July 31, testing on 27 potential COVID-19 vaccines are ongoing across the globe, while over 139 vaccines are currently in the pre-trial development phase. Highest performing vaccine candidates have transcended into clinical development, inclusive of INO-4800 from Inovio, mRNA-1273 from Moderna, pathogen-specific aAPC and LV-SMENP-DC from Shenzhen Geno-Immune Medical Institute, and Ad5-nCoV from CanSino Biologicals (Table 1). Diverse other vaccine developers have declared their plans to kick start human testing subsequently in 2020. One significant COVID-19 vaccine development landscape feature is the series of technology platforms on evaluation, some of which are featuring viral vector (non-replicating and replicating), nucleic acid (DNA and RNA), peptide, virus-like particle, inactivated virus approaches, recombinant protein, and live attenuated virus 1819. Although quite a number of these platforms are currently not the yardstick for licensed vaccines, yet the fields experience in oncology (among others) is propelling the vaccine developers to explore opportunities in next-generation approaches to fast track development and manufacturing speed. It is possible that some vaccine platforms may be better applicable to particular population subtypes (like the children, elderly, pregnant women or immunocompromised patients) 20.

Six stages of the development of vaccine have been outlined by the CDC: Exploratory stage, preclinical stage, clinical development, regulatory review and approval, manufacturing, and quality control. The entire vaccine development process often takes several years, sometimes up to decades 17. Currently, numerous vaccine candidates are transcending from the exploratory stage which is the first stage of vaccine development, into the preclinical and clinical stages. Worthy to note is the fact that 2 months away from the release of the full genome map of SARS-CoV-2, first in-human clinical trials commenced. Of the six stages, the clinical stage remains the longest. Due to the fact that no biologics (vaccines inclusive) or drugs are always with one or two risks, it is imperative to engage safety assessments in human clinical trials. The clinical phase has three divisions namely phase I, phase II and phase III. Two regulatory permissions are required; the Clinical Trial Authorization prior to the clinical stage in order to permit “first in-human” testing, and the Biologic License Application/Approval for vaccine marketing after successful clinical trials. Following clinical studies, there is enrolment and treatment of patients suffering from COVID-19 with aim of achieving sufficient safety and effectiveness of potential vaccines. There is a possibility that thousands of COVID-19 patients may have to take part in the clinical studies prior to approval of therapy or vaccine for use by the general public 1920.

The vaccination decision making calculus spans equilibrium of risk and benefit alongside uncertainty.  The SARS and Zika epidemics were ended before the development of the vaccine funding agencies reallocated funds that had been committed for it, leaving manufacturers with great financial losses and slowing down other vaccine-development programs. Since the overall impact of vaccines demands extensive public acceptance in achieving population-level immunity, right from the onset, policies on vaccination have been subjected to ideological and political debate, featuring individual rights against public health. Several of the vaccine candidates have passed through intensive clinical testing protocols in a bid to prove their efficaciousness and safety 22. However, there is an unrealistically high expectation for COVID-19 vaccine. Paraded as the only “way-out” of the present situation, COVID-19 vaccines are seen by many to be 100% safe and effective even when they are yet to scale through the several rigorous approval protocols and conditions. If there is no “repentance” from the extremely high expectations on COVID-19 vaccine, they might end up catalyzing the narrative that challenges the quality and reliability of vaccines in a bigger way 2223.

Something more is the distrust, wildfires, rumors encompassing the vaccines and even the virus itself. These elements are described by WHO as “infodemic”; in reference to fake news spreading spontaneously and readily than the novel Coronavirus 2. Another striking problem is on the side of vaccine and drug makers. This time, it is not about which vaccine or therapeutic platform should they operate with, it is rather about the paths of conventional clinical development which has proven to be cumbersome, demanding longer time in addressing the present public health threat. With this challenge, quite a number of groups and researchers are now retooling the development process and protocols in a bid to seek for solutions 23.

In giving response to a pandemic arising from a novel viral pathogen with very high infectivity (like wildfire), discovery of commercial biopharmaceuticals may not be solely palatable as response. Vaccine and drug manufacturers are naturally used to charting the course of clinical and regulatory development protocol spanning several years (sometimes up to decades). In the same vein, there is little experience on the side of drug development regulators in pandemic context. There is yet to be an accelerated pathway for COVID-19vaccine development or even for any other emerging infectious disease.

The efforts in progress towards developing a vaccine should be monitored using three prompts: speed, production and deployment in terms of scalability and accessibility globally. Funding is highly needed to achieve a successful vaccine development. The estimate given by the CEPI indicates that at least US$2 billion investment will be needed to develop three vaccines over the nest 12-18 months excluding manufacture or delivery costs.

As obtained in times past, vaccines still serve as a kind of diplomacy aimed at maintaining the basic level of global cooperation. Trust remains the fundamental standpoint that underpins vaccine acceptance. Trust in the steps, processes, practices, licensure, policies, manufacturing and even the deployment of developed vaccines. Having trust in the policy makers, the healthcare professionals – nurses, doctors, community health practitioners and others. If the issue of trust remains unaddressed and understood, efforts at improving the confidence of vaccines to be developed may fail, particularly when the new vaccine technologies currently used as well as the speed through which the vaccines are being developed are involved.