top of page
  • Writer's pictureAnne O

Covid-19 Vaccine Hesitancy and What You Should Know

The jubilation that came with the success of the Covid-19 vaccine development also came with reasonable reservations on vaccine efficacy and safety because of the unprecedented brevity of time it took for vaccine creation and approval. Unlike other vaccines that have severally been proven for safety and efficacy, the Covid-19 vaccine is new and though its development in different variants has leveraged on rigorous research; many delay or refuse receiving the vaccine for fear of how it may alter their body; added to this, is the bogus claim of DNA alternation in some quarters.


Some are particularly concerned that the brevity of time it took for the Covid-19 vaccines to be developed and approved gives credence to their reservation on the safety of these vaccines. Previously, vaccine development to approval would usually require a 10-to-15-year timeline whereas the Covid-19 vaccines have taken less than 2 years for development and Emergency Use Authorization (for the ones currently in use).


The ensuing skepticism has led to vaccine hesitancy in people across multiple divides including social economic status, literacy level, demographics and religious belief. Undoubtedly, having concerns about the safety of the vaccine is a good and natural reaction akin to self-preservation. Self-preservation is innate, it serves to protect one from perceived or impending danger. In fact, critically scrutinizing what goes into one’s body is the sensible thing to do.

Vaccine Hesitancy
Image Credit: EdX

In the same vein, one must also consider the risk and threat to life that being infected with the SARS-Cov-2 virus portends and as such, one could argue that it is also self-preservation that has led many to heartily embrace the vaccines. To clear the air on the unprecedented success of the development of Covid-19 vaccines in the shortest possible time, the following are some pointers to why:

  • Previous Knowledge on Corona viruses – SARS-Cov-2 is a Corona virus and Corona viruses have been studied for decades particularly since the first outbreak of SARS (Severe Acute Respiratory Syndrome) in 2002 and MERS (Middle East Respiratory Syndrome) in 2012 which are also caused by different strains of Corona viruses. Attempts at developing vaccines against Corona viruses are not new and the Covid-19 vaccine development leveraged on previous research in this regard.

  • Global collaboration - Since the pandemic, collaborations from governments, international institutions, private organisations including pharmaceuticals, research institutions and non-profit organisations have gone into controlling and preventing further transmission of the infection. These collaborative efforts across countries and private sectors resulted in fast tract research which according to WHO has reduced clinical trial time by up to 80%.

  • Funding for vaccine development and production – accessing funding for vaccine production is generally a humongous task and another reason why vaccine development and production usually takes longer. One research suggests that an estimated minimum of $2.8 to 3.7 billion will be required to develop a viable vaccine for an infectious disease epidemic. In the case of the Covid-19 vaccine development, it benefitted from an unprecedented access to funding from all fronts (for instance, the European Union pledged $8 billion for vaccine research). This in no small way accounts for part of the acceleration of the vaccine development and production.

  • New vaccine technology – for decades, research has gone into mRNA vaccines particularly for infectious diseases like the flu, Zika, rabies, cytomegalovirus; and lately in the development of a malaria vaccine. The mRNA Covid-19 vaccines by Moderna and Pfizer-BioNtech are the first of its type approved for vaccine use in humans. This new type of vaccines reportedly have accelerated vaccine production time.

  • Vaccine distribution – to ensure access and equitable distribution of the Covid-19 vaccines; Covax, a network of stakeholders including WHO, Gavi, the Vaccine Alliance, Coalition of Preparedness Innovations (CEPI) and UNICEF amongst others teamed up to ensure that at least 20% of every countries’ population have doses of Covid-19 vaccines.

You may also click here and here for more on Covid-19 vaccine safety and efficacy.


Vaccine hesitancy has always been a challenge that dates back to the history of vaccines (you will find a fascinating recount of vaccine hesitancy here) and in more recent years the resurgence of measles outbreak in populations where it was previously eliminated gives credence to proffering an intervention to mitigate vaccine hesitancy and in this instance Covid-19 vaccine hesitancy.

Vaccine Production Process
Image Credit: Council on Foreign Relations

Globally over 600 million Covid-19 vaccine shots have been given covering 8.4% of the global population (data dated 11th May 2021). Different Covid-19 vaccines are been used globally with the commonest ones being the Moderna vaccine, Pfizer-BioNTech vaccine, AstraZeneca vaccine and the Johnson & Johnson Vaccine. For the most part, the vaccines have been observed to be efficient and safe with reports of mild side effects relieved by over-the-counter analgesics, as well as reports of some very rare severe side effects.


The more serious side effects that have been observed and reported are notably associated with the AstraZeneca and Johnson & Johnson Vaccines with rare occurrences of blood clots within 3 to 21 days of vaccination. Initially, these incidences were postulated to be coincidental but have now been classified as very rare side effects and so far, have only been reported in persons younger than 60 years old (with a number of fatalities in a few affected people). In the UK, this very rare side effect is reported as happening in 1 in 250,000 or 4 in a million. Consequently, some countries with access to multiple brands of the Covid-19 vaccines have limited specific brands to certain age groups.


The blood clots can be fatal particularly if it occurs in the brain to cause CVST (Cerebral Venous Sinus Thrombosis) or in the abdomen to cause SVT (Splanchnic Venous Thrombosis). The clots are also observed to be accompanied with reduction in blood platelets referred to as thrombocytopenia. The following are symptoms and signs of blood clots to look out for within 3 to 21 days of vaccination:

  • Breathlessness

  • Pain in the chest

  • Persistent pain in the stomach/belly

  • Severe or persistent headaches or blurred vision

  • Swelling or coldness in a leg

  • Tiny blood clots under the skin beyond site of injection

This condition can be resolved if symptoms are promptly reported and managed effectively. Investigations and research are reportedly on-going to determine the trigger for the rare blood clots.


When I received my jab of the AstraZeneca vaccine, I experienced mild flu like symptoms that lasted for two days and was relieved by over-the-counter analgesics. A number of friends and colleagues reported similar symptoms while the majority only had tenderness at the site of injection. Mentally, I have an overwhelming sense of relief and safety from the virus as I look forward to completing the vaccination process. In the meantime, I will continue to maintain physical distancing and personal hygiene guidelines for self-preservation.


Social distancing and personal hygiene habits though highly effective are not enough to stop the incessant spread of the virus particularly with emergent mutant strains that are sometimes more virulent. The earlier at least 70% of each countries’ population is vaccinated, the closer we are to herd immunity and the sooner Covid-19 infection will belong to history.


Vaccination offers us a quick way of ending the spread of the virus and possibly getting rid of it for good. It is ever pertinent that all avenues to curb the spread of the virus be meticulously adopted. I encourage you to explore the additional resources below for deeper insights into the safety and efficacy of the Covid-19 vaccines.


Truly, “no one is safe until everyone is safe”.



Dr. Anne Olowu is a Public Health Physician and Health Promotion expert with varied work experiences across Africa. She is the Lead Consultant at AnneAide Consulting and writes from Lagos, Nigeria.



Additional References




COVID-19 Vaccines: MODERNA|PFIZER/BIONTECH|ASTRAZENECA. Ninja Nerd Lectures, December 7, 2020; YouTube https://www.youtube.com/watch?v=35Idb_lCU4o


Measles and the case for immunization. Anne Olowu, May 20, 2019; AnneAide Consulting https://www.anneaideconsulting.com/post/how-to-think-through-problems-efficently


The History of Vaccines; An Educational Resource by The College of Physicians of Philadelphia https://www.historyofvaccines.org/timeline/all


An American slave who taught America how to vaccinate itself from smallpox. Carey Baraka, May 10, 2020; Quartz Africa https://qz.com/africa/1854780/an-african-slave-taught-america-to-vaccinate-from-smallpox/


The History of Vaccines and immunization: Familiar Patterns, New Challenge. June 2005, Alexandra Minna Stern and Howard Markel Health Affairs Vol. 24, No. 3 https://www.healthaffairs.org/doi/10.1377/hlthaff.24.3.611


A Vaccine Against COVID-19 Would Be the Latest Success in a Long Scientific History. Jeffrey Kluger; May 15, 2020; Times.com https://time.com/5835668/vaccine-history/


How have Covid-19 vaccines been made quickly and safely? January 2021 https://wellcome.org/news/quick-safe-covid-vaccine-development


5 charts that tell the story of vaccines today. June 02, 2020, Douglas Broom; World Economic Forum https://www.weforum.org/agenda/2020/06/vaccine-development-barriers-coronavirus/


Vaccine Q&A: How Long does It Take to Make Vaccines? December 16, 2020, Matt Shipman https://news.ncsu.edu/2020/12/vaccine-manufacturing-q-and-a/


UN mobilizes global cooperation in science-based COVID-19 responses. April 7, 2020https://www.un.org/en/un-coronavirus-communications-team/un-mobilizes-global-cooperation-science-based-covid-19-responses


A Guide to Global Covid-19 Vaccine Efforts. April 27, 2021; Claire Felter. Council on Foreign Relations https://www.cfr.org/backgrounder/guide-global-covid-19-vaccine-efforts


Estimating the cost of vaccine development against epidemic infectious diseases: a cost minimization study. October 17, 2018; Dimitrios Gouglas et al. The Lancet|Global Health https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(18)30346-2/fulltext



Genetic Engineering Could Make a COVID-19 Vaccine in Months Rather Than Years. Charles Schmidt, June 1, 2020; Scientific American https://www.scientificamerican.com/article/genetic-engineering-could-make-a-covid-19-vaccine-in-months-rather-than-years1/


EU funding - Financing initiatives helping to tackle the outbreak of coronavirus. European Commission. https://ec.europa.eu/info/research-and-innovation/research-area/health-research-and-innovation/coronavirus-research-and-innovation/financing-innovation_en


How did we develop a COVID-19 vaccine so quickly? Jocelyn Solis-Moreira, December 15, 2020; MedicalNewsToday https://www.medicalnewstoday.com/articles/how-did-we-develop-a-covid-19-vaccine-so-quickly


COVAX – Working for global equitable access to Covid-19 Vaccines. 2021 WHO https://www.who.int/initiatives/act-accelerator/covax


Corona virus (Covid-19) vaccinations; Our World in Data; May 11, 2021 https://ourworldindata.org/covid-vaccinations?country=OWID_WRL


What is the blood clotting disorder the AstraZeneca vaccine has been linked to? Linda Geddes; GAVI, 8th April 2021 https://www.gavi.org/vaccineswork/what-blood-clotting-disorder-astrazeneca-vaccine-has-been-linked


AstraZeneca’s COVID-19 vaccine: EMA finds possible link to very rare cases of unusual blood clots with low blood platelets. April 7th, 2021; European Medicines Agency. https://www.ema.europa.eu/en/news/astrazenecas-covid-19-vaccine-ema-finds-possible-link-very-rare-cases-unusual-blood-clots-low-blood


Thrombotic Thrombocytopenia after ChAdOx1 nCov-19 Vaccination. Andreas Greinacher, M.D. et al; NEJM April 9, 2021 https://doi.org/10.1056%2FNEJMoa2104840


Thrombosis and Thrombocytopenia after ChAdOx1 nCoV-19 Vaccination. Nina H. Schultz, M.D. et al: NEJM April 9, 2021 https://doi.org/10.1056%2FNEJMoa2104882


Rare blood clots – what you need to know. Smitha Mundasad, BBC News; 26 April 2021 https://www.bbc.com/news/health-56674796


How worried should we be about links of blood clots to AstraZeneca’s vaccine? Ludwig Burger, John Miller. April 21, 2021; Reuters. https://www.reuters.com/business/healthcare-pharmaceuticals/how-worried-should-we-be-about-links-blood-clots-astrazenecas-vaccine-2021-04-09/


Arterial events, venous thromboembolism, thrombocytopenia, and bleeding after vaccination with Oxford-AstraZeneca ChAdOx1-S in Denmark and Norway: population-based cohort study. Anton Pottegård, professor, et al; BMJ 2021;373:n1114; May 05 2021 https://www.bmj.com/content/373/bmj.n1114


Risk of cerebral blood clots from disease is 10 times that from vaccination, study finds. Ingrid Torjesen. April 16th, 2021; BMJ 2021; 373 https://www.bmj.com/content/373/bmj.n1005


Thromboembolism and the Oxford-AstraZeneca Covid-19 vaccine: Side effect or coincidence? Søren Dinesen Østergaard et al; March 30th, 2021. The Lancet https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00762-5/fulltext


What is Herd Immunity and How Can We Achieve It With COVID-19? Gypsyamber D’Souza and David Dowdy; JHSPH, April 6, 2021 https://www.jhsph.edu/covid-19/articles/achieving-herd-immunity-with-covid19.html


Coronavirus disease (Covid-19): Herd Immunity, Lockdowns and Covid-19. December 31, 2020. WHO https://www.who.int/news-room/q-a-detail/herd-immunity-lockdowns-and-covid-19


Quote “No one is safe, until everyone is safe” by UN https://www.un.org/sw/desa/“no-one-safe-until-everyone-”


Recent Posts

See All
bottom of page