If I delay getting a COVID-19 vaccine, what impact will it have?

Taking a wait-and-see approach to COVID-19 vaccines could lead to only pockets of the population being protected. Will this be enough to end the pandemic?

  • 15 January 2021
  • 4 min read
  • by Priya Joi


The scientists working around the clock to develop vaccines to end the COVID-19 pandemic probably expected most people to be thankful and relieved at the fact that we are starting 2021 with the roll-out of several safe and effective vaccines. Yet despite this, there have been alarmingly high numbers of people hesitating to get vaccinated. 

Most are keen not to identify as "anti-vaxxers," saying that they are pro-vaccine and have vaccinated their children. Instead, their caution about COVID-19 vaccines relates to the speed with which they were developed, and the fact that they are new vaccines. Many of the people refusing the vaccine are those at the front of the queue: in the USA, 40% of health workers in Los Angeles County and 60% of care home workers in Ohio have refused the vaccine. 

Why people might hesitate to be vaccinated

Many people are saying they will get vaccinated eventually, but are waiting to see what happens to the people who have had the first round of vaccines. Yet, if they are really waiting to see how the natural experiment of mass vaccination plays out, they would need to wait for several months or even years to assess side-effects. 

Others are concerned about how fast a vaccine has gone from lab to jab, even though vaccine-makers have been transparent about their process, and there are clear explanations for how a safe and effective vaccine was made in such record time when previous vaccines typically take more than a decade.  

And some are concerned about the use of new technology – the Pfizer/BioNTech and Moderna vaccines both use RNA, a technology that has never been used before in vaccines. However, these technologies are the result of a decade of research and development, which is why they can now be used to produce COVID-19 vaccines.

So, what are the impacts of this refusal to vaccinate?

Clearly, there is an individual impact on people who are willingly allowing themselves to be vulnerable to COVID-19 infection. It’s worth re-iterating here that the virus doesn’t just affect older people and those with underlying conditions. 

Even though young, healthy people may be at a lower risk of death, many are at risk of protracted illness in the form of chronic fatigue, shortness of breath, gastrointestinal problems, a lost sense of smell or taste, short-term memory loss and gynecological problems. These people are now being described as having "long COVID."

An even bigger issue is that vast amounts of time and money were poured into vaccine development to rapidly control the pandemic and restore normal activity, and for this, mass vaccination is crucial. 

Trying to roll out the vaccines across the world simultaneously is a fair and equitable thing to do, but it is also necessary to stop transmission of the virus. It’s unclear at the moment whether the vaccine will stop someone transmitting the virus as well as preventing disease, but in any case, reducing the number of people infected will prevent the virus from spreading further and will save the lives of people who are most vulnerable. If vaccination is staggered more than necessary, there will potentially never be a high enough proportion of people vaccinated to stop constantly passing the virus around. 

A delay in vaccination and building population immunity also gives the virus time to mutate, and if there are populations with partial immunity (when only a small proportion of people are vaccinated) facing a highly transmissible virus, the virus could evolve to be resistant to current vaccines.

Since it’s not yet clear how long immunity after COVID-19 infection or vaccination will actually last, it’s crucial to stop the virus circulating as soon as possible in case immunity starts to wane. If this happens, it will create a window of opportunity for the virus to resurge. This is why speed is just as important as equity in vaccination against COVID-19.