The ambiguous future of the COVID‐19 pandemic in the presence of a vaccine

• Published in: Health science reports Vol. 6; no. 4; pp. e1207 - n/a
• Main Authors: Mazidimoradi, Afrooz, Allahqoli, Leila, Salehiniya, Hamid
• Format: Journal Article
• Language: English
• Published: United States John Wiley & Sons, Inc 01.04.2023; John Wiley and Sons Inc; Wiley
• Subjects: Conflicts of interest; Coronaviruses; COVID-19 vaccines; Developing countries; Disease prevention; Disease transmission; Herd immunity; Infections; International organizations; LDCs; Letter to the Editor; Pandemics; Severe acute respiratory syndrome coronavirus 2; Writing
• ISSN: 2398-8835; 2398-8835
• DOI: 10.1002/hsr2.1207

[...]with the passage of time, the elimination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the presence of effective vaccines faded; after two years of the vaccine development, a high incidence of COVID-19 is observed and the death rate remains one of the health challenges of the world. 4,5 For Covishield and Covaxin vaccines, the reported efficacy after phase III trials were 70.4% and 78%, respectively 6,7; And 43.7% of vaccinated patients admitted to the ICU die due to Covid-19. 8 76.6% of persons who received 2 doses of Sinopharm, Sputnik V, Pfizer, and AstraZeneca vaccines, reported that they did not become infected postvaccination. 9 REDUCTION OF THE EFFECTIVENESS OF VACCINES OVER TIME One reason for the declining protecting role of vaccines against SARS-CoV-2 infection is the reduction of the antibody titers resulting from vaccination over time, and the rate of decline varied according to the type of vaccine. 10,11 Therefore, the effectiveness of BNT162b2 vaccine against SARS-CoV-2 infection with different severities decreased over time from 92% (confidence interval: 95%, CL92 to 93; p < 0.001) in 15−30 days to 47% (39−55; p < 0.001) at 180−121 days, and to 23% (−2 to 41; p = 0.07) from day 211 onwards. 11 Also, since the emergence of SARS-CoV-2, different variants of the virus have been known, some of which have potential characteristics such as increased transmission, virulence, or reduced vaccine effectiveness reduced sensitivity to the vaccine. With the emergence of new strains of the virus, the effectiveness of the existing vaccines also decreases, so that the modern vaccine which was effective against D614G (ancestral type), B.1.1.7 (Alpha), B.1.351 (Beta), P. 1 (Gamma), and B.1.617.2 (Delta) more than 90%, are effective only 48% against omicron strain. 4 WIDE PUBLIC DISAPPROVAL OF EXISTING VACCINES Low perceived benefits of vaccination, social mistrust of the health system, lack of understanding of the risk of contracting COVID-19, concern about possible side effects of vaccines, lack of awareness of vaccines and low level of health literacy, spiritual or religious reasons, the political attitude and exploitation of the COVID-19 crisis, and the existing injustices in access to the vaccine have been reported as the reasons for the lack of public approval of the COVID-19 vaccine. 12,13 INEQUALITY IN VACCINE DISTRIBUTION In the first year of distribution of vaccines against COVID-19, vaccination rates in high-income countries (HICs) were reported to be 75-80%, while in low-income countries (LICs) less than 10% of the population was vaccinated. 14 As the COVID-19 pandemic continues, the disparity in vaccine distribution (especially in the 6 months to 4 years' age group) in low- and HICs has become more prominent. 15,16 While many HICs provide booster doses of COVID-19 to their population, the rest of the world is not vaccinated or their vulnerable groups are vaccinated with only one dose. 17 LACK OF A SINGLE POLICY TO REDUCE COVD-19 AMONG COUNTRIES The lack of implementation of single prevention and control programs to deal with the COVID-19 crisis at the regional level has caused susceptible and non-susceptible populations to be placed next to each other and the transmission chain of infection is still active. 18 In summary, each of the aforementioned items challenges the creation of herd immunity against COVID-19, therefore it may not be easy to achieve herd immunity at the community level; especially when the duration of immunity created by the vaccine and the disease is limited and due to injustices in vaccine distribution, public vaccination is not possible on a large scale. [...]considering that the epidemic of COVID-19 is expected to continue the following solutions are suggested to deal more effectively: 1.