The coronavirus disease 2019 (COVID-19) pandemic continues to wreak havoc across many parts of the world. Mass vaccination against its causative virus – the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) – remains our best hope at arresting the pandemic’s spread through the promotion of herd immunity.

Vaccine rollouts have started across the globe, with many countries ramping up efforts to promptly inoculate as much of their population (especially those susceptible to severe disease) as possible. However, vaccine hesitancy or unwillingness, over fears about the current COVID-19 vaccines’ safety, has been a major concern for public health authorities the world over. It is still unknown what factors influence vaccine intent and whether there are wide disparities across populations.

However, a team of researchers from the USA, Germany and Norway recently found that the main barrier to vaccination is not vaccine hesitancy but a supply shortage and unequal distribution of the vaccines themselves. Their data suggests that large numbers of people across the globe are willing to get vaccinated.

The study, which appeared on the medRxiv* pre-print server, showed that in the study sample in most of the countries examined, the rates of people willing to get vaccinated were high enough to reach more conservative herd immunity levels if combined with the number of those who have recovered from COVID-19.

Immunization against SARS-CoV-2

Since the start of the COVID-19 pandemic in December 2019, scientists have raced to develop effective vaccines in the hopes of curbing viral spread.

To date, there are 182 vaccines in the pre-clinical evaluation and 92 vaccines undergoing trials. Many countries have used vaccines approved by the Food and Drug Administration under an emergency use authorization (EUA).

The hope for stemming the global spread of COVID-19 depends on immunization. Vaccine hesitancy due to fear and misinformation remains a major threat to global health.

If many people globally do not get vaccinated against COVID-19, new viral variants may emerge that escape the vaccine and re-introduce the virus into vaccinated populations. Hence, making sure a majority, if not all, of the global population, is vaccinated is a top global public health priority.

Herd immunity or community immunity is when a considerable part of the population of an area is immune to an infectious disease, which causes chains of viral transmission to break down.

Vaccine intent is influenced by a multitude of factors, from mutual trust built between the public and health authorities to fact-saturated information that reduces doubts created by misinformation.

During the early pandemic, a sizable minority in many parts of the world exhibited reluctance to get vaccinated if a vaccine became available. Meanwhile, previous studies have shown that vaccine intent improved between November 2020 and January 2021 in 11 out of 15 countries surveyed.

The study

In the current study, the researchers assessed the levels of vaccine acceptance over a more extended time that covers more recent developments, such as emergency use authorizations (EUAs) and additional clinical trials, among others.

The team surveyed more than 1.4 million Facebook users from 23 countries across four continents collected in 18 waves between July 2020 and March 2021.

The survey asked the respondents whether they intend to get vaccinated for COVID-19.

The study results showed that vaccine intent varies markedly across countries and over time. For countries that have larger vaccine scales, the intent increased.

Some countries had a stagnant vaccine intent during the study period, while in Egypt, for example, the intent has declined.

In a nutshell, the researchers found that many residents in countries worldwide are willing to get vaccinated. In most countries in the study sample, vaccine intent was high enough to reach more conservative herd immunity levels if the numbers were combined with those who were already infected.

The researchers suggest that the barrier to a successful vaccination effort is not vaccine hesitancy, but rather issues surrounding vaccine supply. Currently, many countries are reporting shortages of vaccines amidst the skyrocketing number of cases.

“This sends a clear message to politicians who need to work on a quick and fair distribution of vaccine; and to scientists who need to focus their attention on understanding remaining pockets of vaccine skepticism or undecidedness and on factors that explain actual vaccine behavior, rather than intent,” the researchers concluded in the study.

Vaccinating as many individuals as possible is crucial today as surging cases are being reported, particularly in India. The country, known as the world’s largest vaccine manufacturer, is battling a second and devastating wave of the pandemic. The number of cases there has topped 18.37 million, with over 204,000 deaths reported.

*Important Notice

medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.

Written by

Angela Betsaida B. Laguipo

Angela is a nurse by profession and a writer by heart. She graduated with honors (Cum Laude) for her Bachelor of Nursing degree at the University of Baguio, Philippines. She is currently completing her Master's Degree where she specialized in Maternal and Child Nursing and worked as a clinical instructor and educator in the School of Nursing at the University of Baguio.