Open access peer-reviewed chapter

Maximizing COVID-19 Vaccine Acceptance in Developing Countries

Written By

Yusuff Tunde Gbonjubola, Daha Garba Muhammad, Nwaezuoke Chisom Anastasia and Tobi Elisha Adekolurejo

Submitted: April 26th, 2021 Reviewed: December 23rd, 2021 Published: April 6th, 2022

DOI: 10.5772/intechopen.102369

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Abstract

Coronavirus disease 2019 (COVID-19) is still in existence, with the capacity to spread even further. Vaccination could efficiently reduce the burden of the pandemic, but first, people must accept these vaccines. Vaccine acceptance by the population is crucial to control the pandemic and prevent further deaths. Herd Immunity, which is the indirect protection that occurs when a sufficient percentage of a population has become immune to an infection, offers some protection to unvaccinated individuals. However, herd immunity is compromised when widespread vaccine acceptance is not achieved. Some vaccines have been authorized to prevent COVID-19, such as Pfizer-BioNTech, Moderna, Johnson & Johnson\'s Janssen, and Oxford-AstraZeneca COVID-19 Vaccine. While vaccine development has been achieved within a short time, its safety, potency, efficacy, and universal accessibility are of great concern and could influence vaccine acceptance. Conspiracy beliefs rampant in Africa may influence vaccine hesitance; exposure to anti-vaccine theories decreases willingness to accept vaccination. As such, there is a need for the availability of reliable information about vaccines, messages that highlight the vaccines efficacy and safety could be effective for addressing the hesitancy to increase the acceptance level of the COVID-19 Vaccine in Africa.

Keywords

  • COVID-19
  • vaccine
  • pandemic
  • herd immunity

1. Introduction

Coronavirus disease 2019 (COVID-19) is still in existence. It is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which started in Wuhan in China [1]. While the third wave of COVID-19 in Africa continues to wane, 108,000 new cases were reported and more than 3000 people died in the week leading up to September 19. The continent currently has nearly 8.2 million cases of COVID-19. The Delta variant has been found in 38 African countries. Alpha has been found in 45 countries, and beta has been found in 40 [2]. According to the European Centre for Disease Prevention and Control (ECDPC), all continents have reported confirmed cases of the virus [3]. COVID-19 is transmitted through respiratory droplets [4]. Transmission rates are reported to be unknown for SARS-CoV-2; however, many authors have reported transmission by direct contact with an infected person. The mode of transmission of SARS-CoV-2 is as other pulmonary diseases, such as influenza [5]. Persons can be infected through contact with a contaminated surface. The virus remains viable on surfaces for lengthy hours. Van Doremalen et al. in a study reported that SARS-CoV-2 remained viable on surfaces for up to 72 hours [6]. Studies have reported that people with COVID-19 who are asymptomatic are still contagious; this has brought about the question: what is the effectiveness of isolation? [7, 8]. Zou et al. [9] reported an increased viral load in symptomatic persons while an asymptomatic person was shedding the virus.

Clinical signs of an infection include fever, headache, dry cough, shortness of breath, and fatigue [10, 11]. Some patients also report digestive symptoms such as diarrhea and vomiting [12]. COVID-19 was observed to have a similar clinical manifestation as SARS [13]. Fever, for example, occurred in 98–100% of patients with SARS compared with 81.3% of patients with COVID-19 [14, 15]. In total, 18.7% of patients had no fever at admission; this means the absence of fever does not necessarily rule out the possibility of COVID-19 [13].

Deaths and disability were directly linked with the first wave of COVID-19, alongside some population living with the aftermath of a severe acute respiratory syndrome, which could persist even after they are clinically cured of the infection [16]. Second-wave victims were those that suffer from the consequence of the measures taken to limit the spread of COVID-19. The victims include but not limited to those who did not present at the hospital due to fear of getting infected; some group of people with progressive disease whose appointments were rescheduled, and those that did not present themselves for routine screening [17]. The third wave was found to be more dangerous [18]. The rate of infection was 1.7 times more than that of second wave and 6.23 times more than the first wave. Although, the death rate was 1.21 times more than second wave, third wave was not as fatal as the first wave (at least 0.46 times less than the first wave) [19]. The third wave has been associated with the effect of the pandemic on the social determinants of health and its effect on the next generation [20]. The health inequalities have been projected to worsen through severe economic set back [21], and the groups at the intersection between poverty and poor health with most likely suffer the most [21].

Prevention of COVID-19 infection is based on adherence to social distancing, patient isolation, quarantine, wearing a mask, and regular washing of hands [22]. In addition to the health impact of COVID-19, there is an economic consequence of this virus as it spans through an increase in unemployment rates and healthcare demand [23]. These negative impacts have encouraged pharmaceutical companies to develop a vaccine urgently. In December 2020, several vaccines were authorized to prevent COVID-19 infection, and more than 50 COVID-19 vaccine candidates are being developed [24]. Vaccination is the most effective means of handling infectious diseases, and its success is confronted by vaccine hesitance [25]. The impact of vaccination against diseases cannot be overemphasized; for example, smallpox was eradicated by vaccine administration [25].

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2. COVID-19 vaccine development

Several vaccines for COVID-19 have undergone human trials and passed. Three vaccines have been approved for administration, and they are Pfizer-BioNTech, Moderna, and Johnson & Johnson’s Janssen. The Centers for Disease Control and Prevention (CDC) has declared that all three vaccines are safe, effective, and will reduce a person’s risk of severe illness [26]. The Bill and Melinda Gates Foundation awarded a US$15 million grant toward the experimental COVID-19 Vaccine by Novavax with research stationed at Witwatersrand University in Johannesburg, South Africa [27]. While vaccine development has been achieved within a short time, its safety, potency, efficacy, and universal accessibility are of great concern [12]. Efficacy is not all required for vaccines to be effective, but it must be accepted by the people [28].

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3. Mechanism of action of COVID-19 vaccines

3.1 mRNA vaccines

3.1.1 Pfizer and Moderna

Both Pfizer and Moderna are mRNA vaccines. These are cutting-edge vaccines made from genetically engineered RNA molecules that through their translation in the ribosomes produce a protein that triggers the immune system of the host to produce antibodies against the antigen-carrying substance or organism [29]. The surface of COVID 19 contains between 25 and 28 proteins, and on this surface is the presence of three repeating protein copies called “spike protein” of COVID 19, but only a copy of one of this repeating subunit is used for formulating the mRNA [30]. This formulated mRNA is enclosed in a lipid nanoparticle to ensure cytoplasmic penetration and ribosome translation leading to the synthesis of the viral spike proteins [29] as well as making delivery easy and preventing the body from damaging it [31]. The synthesized s-proteins displayed on cell membranes activate MHC 1 and MHC 2 complexes and activate the B cells, macrophages, dendtritic cells and attract other cells of the immune system such as T helper cells [32]. Strongly activated T helper cells produce interleukins 2, 4, and 5 [33]. These interleukins stimulate the T helper cells to proliferate memory T cells for recognition of the spike protein and also cause the B-cells to differentiate into plasma cells that eventually produce antibodies against the viral spike proteins, neutralizing or destroying the virus. The efficacy of Pfizer and Moderna for preventing disease or severe disease results in 95–87.5% and 94.5–100%, respectively [32].

3.2 Viral vector vaccines

3.2.1 Astra Zeneca

Astra Zeneca is a viral vector vaccine. This involved the use of a modified version of chimpanzee DNA adenovirus known as ChAdOx1, which no human population has been exposed and does not generate an immune response to the adenovirus but rather to the viral proteins encoded in the host DNA [34]. The genetically engineered DNA vector is used as a template in human cells to generate new chimpanzee adenovirus replicas and produce the viral proteins that is similar to the s-peptide and therefore elicits an immune response. The DNA vector on entry into the cytoplasm of host cells migrates to the cell nucleus, where it gets converted into mRNA using the host enzymes. The mRNA migrates back to the cytoplasm and interacts with the ribosome to synthesize the s-proteins. The proteins get expressed on the cell membranes and form MHC 1and MHC 2 complexes. This is followed by the activation of antibodies, B cells, T helper cells, and plasma cells against spike proteins of COVID 19, destroying or neutralizing the virus [35].

3.2.2 Johnson and Johnson

Johnson and Johnson vaccine, also known as Janssen COVID 19 vaccine, is also a viral vector vaccine made from an adenovirus type 26 and genetically engineered to contain the gene for making spiked proteins of SARS-CoV-2 (glycoprotein (Ad26.COV2-S). The mechanism of action is similar to that of Astra Zeneca. The adenovirus vector is manipulated in the laboratory to delete the gene for replication to avoid replication in human cells [36]. When injected into human body, the DNA carrying the information for the SARS-CoV-2 spike protein is transferred into the nucleus without being incorporated into the host cell DNA. The viral DNA causes the cell to produce more adenovirus particles. It gets translated into mRNA and transported out to the cytoplasm. Ribosomes convert information in these mRNA to form spike proteins. These spike proteins present at the surface of cells induce production of T-cells (CD4 and CD8), cytotoxic cells, plasma cells, Interleukins, and B-cells that constitute the three primary immune responses (antibodies, killer CD8 T-cells, and helper CD4T-cells) to block the infection [37]. T cells destroy infected human cells while antibodies protect uninfected cells from circulating free viral particles.

The efficacy of Astra-Zeneca and Janssen is about 70% and 65%, respectively; in the case of Janssen, it depends on the geographical area ranging from 72–57% [32].

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4. COVID-19 vaccine acceptance

Vaccine acceptance by the population is crucial to control the pandemic and prevent further deaths. Herd Immunity, also known as population immunity, offers some protection to unvaccinated individuals when a significant percentage of the population is immune to that disease. Herd immunity, however, is compromised when widespread vaccine acceptance is not achieved [38]. Vaccination could efficiently reduce the burden of the pandemic [39]. However, a reasonable level of vaccine acceptance is needed [40]. As the vaccine is now available, its public acceptance is about 67% in the United States of America [41]. From the history books, Africa has always been a passive recipient of vaccines, and the reason for this is multifactorial [26]. Vaccines have been a successful measure of disease prevention for decades [42]. However, vaccine hesitancy and refusal are significant global concerns, prompting the World Health Organization (WHO) to declare this uncertainty among the top 10 health threats in 2019 [43].

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5. Herd immunity and COVID-19 vaccine

Herd immunity, first published in 1923, is a concept that refers to the reduced risk of an individual getting an infection from an already infected individual because of the resistant immunity of a large proportion of the population [44]. With this concept, the fight against infection in a population can be achieved even when it is impossible to vaccinate the entire population [45]. Immunization coverage of about 80% of individuals against the smallpox virus reduced the transmission rate and eradicated the disease [46]. Individuals with compromised immunity as a result of diseases such as HIV/AIDS may not be able to be vaccinated, but they are still being protected from the infection through herd immunity, by staying among people who have been vaccinated [47]. The administration of COVID-19 vaccines is expanding daily, and this brings us a step closer to the goal of COVID-19 herd immunity [26, 48].

Herd immunity, also known as indirect protection, community immunity, or community protection, refers to the protection of susceptible individuals against an infection when a sufficiently large proportion of immune individuals exist in a population [49]. In other words, herd immunity is the inability of infected individuals to propagate an epidemic outbreak due to lack of contact with sufficient numbers of susceptible individuals [49]. It was initially introduced more than a century ago and in the latter half of the twentieth century, the expansion of immunization programs and the need for describing targets for immunization coverage, discussions on disease eradication, and cost-effectiveness analyses of vaccination programs make the term “herd immunity” more popular [50]. The disappearance of smallpox alongside the sustained reduction in the incidence of disease in elderly population who were not vaccinated following routine childhood immunization with conjugated Haemophilus influenzaetype B and pneumococcal vaccines are successful examples of the effects of vaccine-induced herd immunity [50].

The herd immunity threshold is defined as the proportion of individuals in a population who, having acquired immunity, can no longer participate in the chain of transmission [51]. If the population of those with immunity falls beyond this threshold, current outbreaks will extinguish and endemic transmission of the pathogen will be interrupted [51]. The durability of immune memory is a critical factor in determining population-level protection and sustaining herd immunity in both naturally acquired and vaccine-induced immunity [52]. In the case of measles, varicella, and rubella, long-term immunity has been achieved with both infection and vaccination. But such durable immunity has not been observed in coronal virus [52].

Herd immunity is an important defense against outbreaks and has shown success in regions with satisfactory vaccination rates [49]. Notable is that even small deviations from protective levels can allow for significant outbreaks due to local clusters of susceptible individuals, as has been seen with measles over the past few years. As such Saad [49] concluded that vaccines must not only be effective, but vaccination programs must be efficient and broadly adopted to ensure that those who cannot be directly protected will nonetheless derive relative protections.

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6. Hesitancy toward the COVID-19 vaccine

Vaccine hesitancy is defined as a delay in the acceptance or refusal of a vaccine despite the availability of vaccine services [53]. Vaccine hesitancy is a public health threat as it serves as a barrier to immunization coverage, especially in developing countries [46]. Conspiracy beliefs, which are common in Africa, may influence vaccine hesitance as exposure to anti-vaccine theories decreases willingness to accept vaccination [43]. Different studies across the world have shown varying rates of vaccine acceptance among people [41, 54, 55, 56, 57]. The results of these studies show that there is some vaccine hesitancy toward the COVID-19 vaccines among different demographics. In a study conducted among 672 adults in the United States, 67% said that they would accept a COVID-19 vaccine if it is recommended for them [41]. Another study conducted across 19 countries reported a 71.5% acceptance rate among participants [56]. In Africa, the hesitancy toward the vaccines appears to be larger.

According to the latest data from South African fintech company, Comparisure, only 48% of South Africans said they would take a COVID-19 vaccine if it was available [21]. In a study conducted among Cameroonians, the vaccine hesitancy rate was 84.6%, and this percentage includes participants who said they will need more information, do not know or will not take a COVID-19 vaccine [58].

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7. Factors that cause hesitancy toward COVID-19 vaccines

The causes of vaccine hesitancy toward the COVID-19 vaccines are intersectional. One of the factors that affect the vaccine-acceptance rate among people is the efficacy of the vaccine. In a study conducted in South-East Asia, 93.3% of respondents said they would like to be vaccinated for a 95% effective vaccine, but the acceptance rate dropped to 67% for a vaccine with 50% effectiveness [55]. Other factors that influence vaccine hesitancy include a perception that vaccines are not beneficial, pain and needle fear, negative information about vaccination on social media, and a lack of knowledge about vaccines [58]. Lower educational attainment and a lower household income are factors that can drive vaccine hesitancy [55]. The causes of vaccine hesitancy had also been reported in different studies, including religious reasons, personal beliefs, and safety concerns due to widespread myths, including the association of vaccines and autism, brain damage, and other conditions [59].

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8. Consequences of vaccine hesitancy toward COVID-19 vaccines

Vaccine hesitancy has many consequences. These consequences can be public-health-related and even socioeconomic. Vaccine hesitancy will increase the incidence of COVID-19 infections. Herd Immunity, which offers some protection to unvaccinated individuals, is compromised when widespread vaccine acceptance is not achieved [38]. One study found that a 5% reduction in measles, mumps, and rubella vaccination in the United States resulted in a threefold increase in annual measles cases [60].

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9. Approach to maximizing COVID-19 vaccine acceptance

Community participation has been identified as a key approach to maximizing COVID-19 acceptance in developing countries. Mobilization of community members can be achieved through religious leaders, chiefs, and royal heads’ involvement in the process [61, 62, 63]. There are two major goals of community mobilization. The first is to ensure proper education on the benefits of the vaccine with the assistance of health professionals [61, 62, 63]. Second is to maximize uptake of COVID-19 vaccine when it becomes available to the public. Failure of the community to accept the vaccine would result in adverse consequences such as resource wastage. Community participation will make enhance and promote the availability of the vaccine in each African setting through a well-structured planning process of vaccine production and procurement [61, 62, 63]. More so, integration of the COVID-19 vaccine into the existing healthcare services presents a promising strategy to overcome the problem of vaccine hesitancy to improve vaccine acceptance maximization [61, 62, 63]. Integration of the COVID-19 vaccine in healthcare facilities reduces the time people spend on vaccine collection. It is worthy of note that the integration of the COVID-19 vaccine in health facilities (primary healthcare centers) promotes its proximity to residential areas, thus reducing the individual’s cost of transportation [61, 62, 63]. The National Primary Health Care Development Agency should be both responsive and responsible in this regard.

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10. Conclusion

Vaccine hesitancy may hinder herd immunity, an important aspect of curtailing COVID-19. Efficacy of the vaccine, misinformation on the vaccine by religious leaders and the masses are part of the causes of hesitancy. Acceptance of the COVID-19 vaccine by the general population is so important for achieving a wide range of immunization coverage to bring the pandemic to an end. Community mobilization by community elders has been suggested as a way of getting to people in the community and could improve vaccine acceptance in Africa. There is also a need for the availability of reliable information about vaccines, messages that highlight the vaccines efficacy and safety could be effective for addressing the hesitancy to increase the acceptance level of the COVID-19 vaccine in Africa.

Conflict of interest

Nil

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Written By

Yusuff Tunde Gbonjubola, Daha Garba Muhammad, Nwaezuoke Chisom Anastasia and Tobi Elisha Adekolurejo

Submitted: April 26th, 2021 Reviewed: December 23rd, 2021 Published: April 6th, 2022