Decision Analysis of the COVID-19 Vaccines

The Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE) is one of the best multiple criteria decision-making tool available which allows users to effectively evaluate and rank alternatives based on certain criteria (17). The ranking will eventually produce a desirable ranking from the most preferred alternative to the least preferred alternative. When compared with other Multi-Criteria Decision Making (MCDM) method, PROMETHEE differs by its capability to enable the decision-maker to use different types of preference functions for each criterion (17). PROMETHEE can simultaneously analyze quantitative and qualitative data. It can also deal with fuzzy relations, vagueness and uncertainties of the data, and give users maximum control over the weights of the criteria (17). Applying PROMETHEE to a real-life scenario is easy and straightforward. Decision-makers only need to assign an appropriate weight and preference function to every criterion selected (18). The weight highlights the importance of each criterion to the alternative and it ranges from 0-1(17). The higher the importance, the higher the weight assigned. The preference function indicates the difference of alternatives based on a specific criterion. Both the weighting and the preference function can be set by the user based on various circumstances (17).

To effectively evaluate vaccines based on specific criteria, a triangular fuzzy linguistic scale of importance is used as shown in Table 1. This linguistic scale indicates the significance of each criterion. Using the Yager index the fuzzy values of the linguistic scale has been defuzzified. After collecting the necessary data as shown in Table 2, the Gaussian preference function was utilized for each criterion.

As of February 3, 2021, there were 289 experimental COVID-19 vaccines in development, 66 of which were in different phases of the clinical trial, including 20 in phase 3 (19). Our study is aimed towards evaluating fifteen (15) vaccines based on the criteria namely; dose number, dosing schedule, storage temperature, efficacy, and side effect using fuzzy-based MCDM technique. This will help decision-maker in the selection process and administration of safe vaccines for the population at large. This technique’s main advantages include; its user-friendliness, completeness of ranking, and applications to real-life planning problems (20).

The number of dosage required for full immunity plays an important role in the selection of vaccines. It is believed that people often prefer a single dose of the vaccine rather than receiving the vaccination twice. This will prevent a possible inflammation at the site of injection. In a situation where a double vaccination is imminent, the majority of the population will prefer to receive the second dose within a short period so they can go back to their life without the fear of getting infected with the coronavirus. There are groups of people with great fear for any medical procedure which involves needle injection into the body, hence, can be considerably impacted by COVID-19 vaccination. In some cases, they may decide not to be vaccinated. Also, needle injection through the intramuscular route is preferable to the intradermal route (21). This will make intramuscular vaccines more acceptable when compared with the intradermal route. Other criteria such as storage advantages, efficacy, side-effect and medical emergency authorization play an important role in choosing a vaccine. Vaccines with a very low storage temperature will cause serious logistic problems and improper storage of the vaccine will render it ineffective. An adverse side-effect is a major factor in vaccine production. The primary goal of a vaccine is to protect the body from a disease with little or no side effect (22). Any vaccine with a considerably serious side effect will jeopardize its usefulness and render its fatal.

According to our study, EpiVacCorona is the most preferred COVID-19 vaccine while Covishield is the least preferred alternative. EpiVacCorona is a COVID-19 preventive vaccine developed by the Vektor State Research Center of Virology and Biotechnology in Russia (23). EpiVacCorona is an antigens-based vaccine that provokes an immune reaction against COVID-19 and promotes the further development of immunity. It is administrated via the intramuscular route as two dosages with a time range of 21 to 28 days (24). EpiVacCorona with a net flow of 0.3242 as shown in Table 3 outperformed all other alternatives. It has an efficacy of 100% and a very low side effect. This contributes to its outstanding performance when compared with other alternatives. Covishield is made from a weakened version of a common cold virus (known as an adenovirus) from chimpanzees (25). It has been modified to look more like coronavirus, although it can't cause illness. The vaccination is administered in two doses between four and 12 weeks and can be stored between 2^oC to 8^oC (25).

Covishield has a net outranking flow of -0.3408 and a positive and negative outranking flow of 0.0006 and 0.3414 respectively. The ranking of other alternative is presented in Table 3. Sputnik V ranked second. It is a 2 dose vaccine manufactured by the Gamaleya Research Institute, part of Russia’s Ministry of Health. It has an efficacy rate of 95% and has received emergency use approval in Russia and dozens of other countries (26). It ranked second with a net flow of 0.1977. Pfizer/Biontech and Moderna vaccines which ranked 5th and 6th respectively are mRNA vaccines that are 95% and 94.5% effective at preventing laboratory-confirmed COVID-19 illness in people without evidence of previous infection. They are both manufactured in the United State of America (USA) by Pfizer Inc. and BioN-Tech and Moderna pharmaceutical company respectively. Both vaccines have been approved by the Food and Drug Administration (FDA) in the USA for emergency use (27). Johnson & Johnson vaccine ranked 13th. It is a viral vaccine produced by Janssen Pharmaceuticals Companies of Johnson & Johnson in the USA. It is a one-dose vaccine with 72% effectiveness in clinical trials at preventing laboratory-confirmed COVID-19 illness in people who had no evidence of prior infection 2 weeks after receiving the vaccine (28).

CanSino Biologics Inc.’s experimental coronavirus vaccine is also a one-dose vaccine with an efficacy rate of 65.7% at preventing symptomatic cases. Cansino is the first non-replicating adenovirus type-5 (Ad5) vectored COVID-19 vaccine to be approved in China (29). The vaccine has an efficacy of 90.07% at preventing severe disease after 28 days following a single dose. According to our study, it ranked 14th in preventing COVID-19. The Sinopharm vaccine is suitable for the prevention of the disease (COVID-19) caused by the new coronavirus infection. It is a single short vaccine approved for emergency use in China and several other countries. In April 2020, China approved clinical trials for a candidate COVID-19 vaccine developed by Sinopharm's Beijing Institute of Biological Products (BBIBP-CorV) (29) and the Wuhan Institute of Biological Products (WIBP-CorV) (30). Both vaccines are chemically-inactive whole virus vaccines for COVID-19 and ranked 11th and 11th with an equal net flow of -0.1280. Sinovac/CoronaVac is a COVID-19 vaccine (inactivated virus) developed by the Chinese company Sinovac Biotech. A real-world study of millions of Chileans who received CoronaVac found it 67% effective against symptoms, reduced hospitalizations by 85%, intensive care visits by 89%, and deaths by 80% (31).

Sinovac/CoronaVac ranked 8th with a net flow of -0.0468. Oxford/AstraZeneca, Novavax, Janssen Pharmaceutical, Inovio Pharma. + International Vaccine Ins, Bharat Biotech, Medicago/GSK, and Pune-based Serum Institute of India (SII) are the other vaccines considered for the study. These vaccines are recommended to be injected into the muscle of the upper arm (27) with notable side effects such as tiredness, headache, muscle pain, chills, fever and nausea.