Covid-19 Vaccines Myth-busting

Covid-19 Vaccines 

One of the most urgent vaccines in our current situation, the Covid-19 pandemic, is the Covid-19 vaccine. Originating from a disease outbreak in Wuhan, China, Covid-19 (coronavirus disease 2019) is an airborne infection caused by coronavirus type SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). Covid-19 affects the lungs, airways, and other parts of the body such as the liver and kidney. Covid-19 is highly infectious as it may spread through air droplets when people cough, sneeze, and talk, or transferred between surfaces harboring landed droplets. Infections caused by SARS-CoV-2 may lead to serious illness and even death in severe cases. Symptoms of Covid-19 generally include a fever (38oC and above), dry coughs, tiredness, difficulty breathing, and loss of smell or taste (anosmia) (World Health Organization, 2021).

Why Should You Get Vaccinated? 

Declared a pandemic on March 2020, SARS-CoV-2 has rapidly mutated to more than 10 global variants, as well as infected nearly half a billion (494 million) worldwide as of April 2022 (Our World in Data, 2022). Viruses constantly change through mutation, sometimes resulting in a new variant that persists in the environment. Callaway (2022) states that new variants will continue to emerge, some causing more severe symptoms that lead to hospitalization (e.g. delta), while others spreading faster (e.g. omicron). In response to the rapid infection of Covid-19 and emergence of concerning variants, the Center for Disease Control and Prevention (CDC) strongly recommends eligible individuals (aged 12 and above), especially those in high-risk communities such as the elderly (aged 60 and above) and healthcare workers to get vaccinated against Covid-19. Individuals are advised to be fully vaccinated (2 times) and receive a booster (3rd vaccine) for optimum immunity in protecting themselves and the others around them.

Covid-19 variants of concern according to the World Health Organization. Credit: Vejthani (2021)

Covid-19 vaccines provide protection for individuals by reducing the risk of severe illness, hospitalization, and death caused by a SARS-CoV-2 infection. Although preventive measures such as washing hands regularly, wearing a mask, and physical distancing are also advised to prevent infection, the Covid-19 vaccine can help combat the pandemic by reducing hospitalization and death rates caused by serious Covid-19 symptoms, thereby helping authorities maintain essential healthcare services. According to the Singaporean Ministry of Health (2022), unvaccinated people aged 80 and above were 20 times more likely to get infected by Covid-19 as compared to those who are fully vaccinated with an additional booster shot. The Washington State Department of Health (2022) also stated that unvaccinated individuals are 5 to 7 times more likely to be hospitalized due to Covid-19 infection depending on age group. Moreover, the elderly over 80 years of age in Chile were 3 times more likely to die from Covid-19 as compared to those who had received a full vaccination and booster. These values indicate that vaccinations are a critical step in preventing Covid-19 hospitalization and death.

In early 2020, American, European, Asian, and African countries all reported a critical shortage of ventilator machines and hospital beds due to the excessive number of admitted Covid-19 patients (Ranney et al., 2020). According to Liddell et al. (2020), approximately 2.5% of Covid-19 patients required mechanical ventilation. Despite having 172,700 ventilators, the United States also had to scramble for ventilators to face their national health emergency. Countries such as Japan, China, Italy, and France made headlines as they raced against each other to pre-order ventilators from already backlogged machines for as much as 8 months in advance. During this healthcare emergency, doctors had to make "decision-making support", meaning that life and death decisions were made based on a patient's relative "capacity to benefit quickly". Patients with a worse prognosis were withdrawed from treatment to provide for others who required the same resource. As a result, millions died, and some, unlawfully. To prevent such events from happening again, lawful citizens must abide by the recommendation of the WHO, CDC, and national governments to receive full vaccinations.

Covid-19 patient using a ventilator in the ICU. Credit: Tessier via The World Economic Forum (2020).

Do Vaccine Brands Matter? 

The WHO works in collaboration with central governments to fully vaccinate 70% of the global population in efforts to reach worldwide herd immunity. As of January 2022, WHO has evaluated 9 vaccines, namely AstraZeneca-Oxford, Johnson and Johnson, Moderna, Pfizer-BionTech, Sinopharm, Sinovac, COVAXIN, Covovax, and Nuvaxovid against Covid-19, all of which met the necessary criteria for safety and efficacy (>50% efficacy). Each of these vaccines are either mRNA, viral vector-based, protein sub-unit, or whole-virus type depending on their active ingredients.

Comparison between different Covid-19 vaccine brands. Credit: Vejthani (2021).

Among these 4 types, people have mainly raised contradictive questions about viral vector-based vaccines due to its main ingredient, all of which have been directly answered by the CDC. It is important to first understand the process and ingredients contained in a viral vector-based vaccine. Viral vector vaccines use a harmless and modified version of the targeted virus called the vector virus to deliver important instructions to our muscle cells. The cells will then produce a harmless piece of spike protein that is unique to SARS-CoV-2. Once produced, the cells will display the spike protein on their surface for the immune system to recognize as a pathogen, triggering the production of Covid-19 antibodies. Based on this explanation, we can answer the questions below:

1. Q: Will viral vector-based vaccines cause Covid-19 since it contains a virus?
   A: The vector virus is harmless. It is not the virus that causes Covid-19, and thus cannot cause Covid-19 infection.
2. Q: Will the vector virus affect or interact with our DNA?
   A: The genetic material delivered by the vector virus cannot integrate into DNA.
3. Q: Will the spike protein persist in our body and cause negative effects?
   A: Spike proteins are estimated to stay in the body for up to a few weeks, just like any other protein the body creates.

Schematic explanation of how a viral vector vaccine works. Credit: Royal Society of Chemistry (2021).

Viral vector vaccines for Covid-19 such as Sinovac and Johnson and Johnson have been approved by the WHO, CDC, and FDA after surpassing safety and efficacy standards. Thus, it is safe to receive viral vector vaccines (National Center for Immunization and Respiratory Diseases, 2022).

Although no vaccine is 100% protective,  all of the approved vaccines will provide protection against serious illness, hospitalization, and death. The WHO states that whatever vaccine is made available should be immediately taken to provide immunity. Available vaccines in a certain country depends on national authorization or diplomatic relationships. China-produced vaccines such as Sinovac have been proved to be 51% effective in preventing Covid-19 in late-stage trials in Brazil, and trials in Indonesia and Turkey showed a higher efficacy rate of up to 84%. Based on a post-trial study conducted in Chile, Sinovac was also 80% effective at preventing death from Covid-19 despite the emergence of new variants (Mallapaty, 2021). Beijing-produced Sinopharm was also proved to be 79% efficacious against symptomatic Covid-19 (Mallapaty, 2021).Respiratory Diseases, 2022).

Despite surpassing the safety and efficacy standard upheld by the WHO, Sinovac and Sinopharm are mostly only administered in low-income countries such as Chile and Bostwana. On the contrary, high-income countries in America and Europe neither authorize nor recognize China-produced vaccines, especially since these countries have raised concerns regarding the Wuhan lab-leak theory. Then-president Donald Trump of the United States was the first to promote this controversy in 2020, and current President Biden called upon a global investigation to consider this possibility in 2021. WHO-appointed scientists Bloom et al. (2021) directly investigated this case and concluded that the lab-leak theory was extremely unlikely, but Dr. Anthony Fauci, Chief Medical Adviser of the United States, continued to express concerns regarding this issue. China immediately denied accusations of engineering SARS-CoV-2 as a bioweapon, and even threatened the U.S. Government that it would withhold crucial supplies such as vaccines if the current administration continued to accuse China of mishandling the outbreak. Following this threat, the Biden Administration refused to accept the heavy-handed vaccine diplomacy from China, stating that the Chinese Communist Party was pushing its economic expansion and political agenda in the Western Hemisphere (Rogin, 2021). Other countries have since done the same, but with less public reasons.

Another American country, Canada, currently approves only 6 out of 9 WHO-approved vaccines, namely Moderna, Pfizer-BionTech, AstraZeneca, Johnson and Johnson, Novaxovid, and Medicago Covifenz. Jillian Kohler, Director of the WHO Collaborating Centre for Governance, Accountability, and Transparency in Pharmaceutics states that Health Canada has not yet approved of Sinovac and Sinopharm due to transparency issues. Sinovac and Sinopharm are both produced by Chinese vaccine manufacturers who do not provide "reliable and transparent" clinical trials as compared to vaccines produced in Western countries (Beattie, 2021). Countries in the European Union also do not approve of Chinese-manufactured vaccines for the same transparency issues. The EU vaccine passport only accepts American and European-produced vaccines including Moderna, Pfizer-BionTech, AstraZeneca, and Johnson and Johnson, meaning travelers are only allowed entry into specific countries based on the brand of the vaccine they received. Even AstraZeneca-Oxford, which is originally manufactured in the United Kingdom, will not be accepted if the vaccine was manufactured under the license of the Serum Institute in India. On the contrary, China has not yet approved of foreign vaccines including Pfizer-BionTech and Moderna, directing their people to receive self-produced Sinovac and Sinopharm instead.

Number of countries using specific Covid-19 vaccines as of February 16, 2021. Credit: Our World in Data via The New York Times (2021).

Countries who do not authorize all WHO-approved jabs are discriminating against each other for political and economic agendas when the main priority of administering vaccines is to provide the people with urgent health protection against the highly infectious Covid-19. Restricted vaccine authorizations due to the diplomatic distrust of many countries have led to the development of discriminatory travel systems. Citizens who had previously gotten the Sinovac vaccine reported receiving third and fourth shots from a different brand to be allowed entry into Europe and the United States (Beattie, 2021). Countries that do not acknowledge all WHO-approved vaccines are undermining confidence in life-saving vaccines that have already been proven as safe and effective, affecting uptake of vaccines and putting billions of people at risk.

Interestingly, Sinovac is the most sought-after vaccine brand in Indonesia. Based on data provided by the National Ministry of Health (2020), 186 out of 235.6 million doses (79%) administered between January and October 2021 were Sinovac vaccines. According to Health Minister Budi Gunadi Sadikin, the Indonesian government had only 3 major considerations, namely approval, authorization, and stock before choosing Sinovac as the main Covid-19 vaccine for its people. Sinovac was the first batch of vaccines to arrive in Indonesia and had already been approved by the WHO as well as authorized National Food and Drug Supervisory Agency (BPOM) for immediate administration. Indonesia had also purchased Novavax, Pfizer-BionTech, and AstraZeneca-Oxford vaccines, but all of them could not be delivered on time and had to be further evaluated by BPOM before receiving national authorization (Fauzia, 2021). Following the advice given by WHO for local authorities and unvaccinated people, the Indonesia government provided whatever vaccine was available first, advising citizens that "the best vaccine is the one available for grab". Siti Nadian Tarmizi, a Covid-19 vaccine spokesperson for the National Ministry of Health also added several more points. Tamizi stated that dosage count, affordability, and product supply to distribution channel were also important deciding factors. As an affordable single-dose vaccine, Sinovac was considered an accessible and efficient vaccine brand. Furthermore, Sinovac vaccines could be locally manufactured by a state-run pharmaceutical company, BioFarma, under license from the main Chinese company (Nugraheny, 2020). Local production meant less delivery time and easier distribution, both of which benefit the vaccination process in Indonesia. Other countries should follow in the footsteps of nations like Indonesia who authorize all WHO-approved vaccines to prioritize herd immunity as a strategy to curb the pandemic.

Covid-19 vaccine campaign against brand discrimination. Credit: World Health Organization West Pacific Region (2021).

Why Are Booster Brands Different? 

With the ever-evolving mutation of viruses, including SAR-CoV-2, lethal variants such as delta in late-2020 and omicron in late-2021 have emerged to create a spike in infection, hospitalization, and death rates. The WHO, CDC, and central governments have since urged all eligible individuals (those aged 18 and above who have received 2 prior vaccination shots) to receive an additional booster shot. Since most countries in America and Europe do not recognize Sinovac due to transparency issues, it is only reasonable that the same brand is not recognized as a booster in the same countries. However, in Indonesia where nearly 80% of the citizens had already received Sinovac vaccines, Sinovac boosters are not authorized. Instead, only Pfizer-BionTech and Moderna vaccines are provided as boosters by the government. According to Sinovac, 94% of trial participants who had received 3 Sinovac shoots produced a sufficient amount of neutralizing antibodies. However, results from a study conducted in Hong Kong showed that Sinovac booster shots do not provide adequate protection against the omicron variant, while Pfizer-BionTech boosters significantly improved protection for those who had previously received 2 Sinovac shots (Yiu, 2021). These results are reasonable as omicron was reported to be 10 times better than delta at evading Covid-19 vaccines, meaning that not all of the vaccines are effective against certain variants (Yiu, 2021). Nevertheless, Sinovac vaccines are still effective when taken as the first two shots, and should be taken if available.

Covid-19 booster brand mix and match. Credit: Homage Malaysia (2021).

Are No Side Effects A Bad Sign? 

As a 17-year-old Indonesian citizen, I enthusiastically received the full dosage of Sinovac vaccine (0.25 mL per dose) in mid- to late-2021. During both vaccinations, I did not feel any side effects except for a sore arm and drowsiness for a few hours. After consulting 3 of my family members (female aged 19, female aged 48, and male aged 49) who had also been vaccinated with Sinovac, they reported the same side effects. All 3 of them also received a Moderna booster (0.5 mL) 6 months later. Two members reported feeling fatigued, dizzy, and feverish at night, while the other only reported diarrhea. Meanwhile, an Australian relative (male aged 30) who had gotten the Moderna shot and booster reported severe stomach pains, diarrhea, fatigue, and a high fever that lasted for 2-3 days. Based on phase 1 and 2 clinical trial data published in The Lancet, participants who received Moderna and AstraZeneca-Oxford vaccine shots reported a higher occurrence of fever (Zhang et al., 2021). Other common infects include fatigue, diarrhea, and injection-site pain and muscle pain (13-21%).

When comparing the side effects of regular (first and second dose) to booster shots, it is important to note that regular vaccines are administered twice with a dosage of 0.25 mL each time over the span of a month, while booster shots are given all at once with a full dose of 0.5 mL. It is only reasonable that a higher dose leads to more significant side effects, but why do people who receive the same shot from the same brand (e.g. Moderna booster) still experience different reactions? Previous studies show that fevers following a vaccination act as thermal regulators that ensure the immune system will respond to the vaccine (Evans, 2015). Thus, the observation of distinct side effects between vaccine brands led to the following question: does the absence of side effects following a vaccination indicate a low antibody response?

According to Johns Hopkins researchers Debes et al. (2021), Covid-19 vaccines followed by little to no side effects still produce an adequate amount of spike antibodies to neutralize SARS-Cov-2. Pfizer-BionTech clinical trial results showed that 50% of participants did not report significant side-effects, yet 90% developed immunity against Covid-19. Moderna also reported that only 10% of its clinical trial participants experienced common side effects, but 95% still developed immunity. Different people show different reactions when developing protective immunity against viruses.  In most cases, the innate immune response is what causes common side-effects by initiating inflammation, while the adaptive immune response only assists innate immunity throughout the process (Cronkite & Strutt, 2018). When the inflammatory response is exaggerated in some people, side-effects such as injection site pain, fever, fatigue, diarrhea, and dizziness may occur. Previous studies suggest that several factors such as age and gender may contribute to the exaggeration of inflammatory immune responses. People above the age of 65 have been reported to show fewer side-effects to the Covid-19 due to gradual age-related decline in immune activity (Weinberger et al., 2008). This decline is also related to lower antibody levels, but adequate protection against the virus is still provided. Women are almost 4 times more likely than men to show vaccine side-effects (79% to 31%) (Gee et al., 2021). Since testosterone is known to help suppress inflammation, men who produce 20 times more testosterone than women experience fewer side-effects (Kanda et al., 2003). However, antibody count is not affected.

Common covid-19 vaccine symptoms. Credit: Bangkok Hospital (2021).

Conclusion

Although different people show distinct reactions to the Covid-19 vaccine, immunity against Covid-19 is still established. Either way, the vaccine provides protection. Therefore, all WHO-approved Covid-19 vaccines are effective in protecting the body against serious Covid-19 illnesses. Vaccine brands and side effects should not be the basis of deciding whether or not to get vaccinated. You too, should get vaccinated immediately (if not already)--- to protect yourself and your loved ones. 

Click here to register yourself for a Covid-19 vaccine in Indonesia!

References 

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