A study conducted by the UK Health Security Agency has recently estimated the rate of hospitalization and death due to coronavirus disease 2019 (COVID-19) among unvaccinated persons residing in England. The study finds that a significant number of hospitalizations and deaths may happen if these unvaccinated populations become infected with the omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The study is currently available on the medRxiv* preprint server.
Study: Estimating the risk of hospitalisation and death in England's remaining unvaccinated population. Image Credit: Anishka Rozhkova/Shutterstock
*Important notice: medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.
Background
About 80% of the adult population in the UK have received at least two doses of the COVID-19 vaccines as of early 2022. In addition, about 67% of the population have received the third booster dose. Despite high vaccine coverage, a small but significant proportion of the UK population remains unvaccinated because of a lack of access or hesitancy to vaccination.
People's hesitancy to receive COVID-19 vaccines is associated with various factors, including uncertainty about vaccine safety and efficacy, disbelief in government policies, and socio-cultural and religious beliefs. In addition, misinformation spread by anti-vaccination campaigns strongly discourages people from receiving COVID-19 vaccines.
In the current study, the scientists estimated the mortality rate in 2021 among unvaccinated people in England who have access to the COVID-19 vaccine but are hesitant to receive it. In addition, they have predicted the rates of hospitalization and mortality in the unvaccinated English population under two hypothetical situations. In one situation, they have assumed that no further vaccination has been done and unvaccinated people have become infected with SARS-CoV-2. In the other situation, they have assumed that most vaccine-resistant people have received full vaccination.
The study has focused on any deaths that occurred within 60 days of COVID-19 diagnosis. The analysis has been done by considering vaccination rates in five age groups, including 15-24 years, 25-44 years, 45-64 years, 65-74 years, and >75 years.
Mortality rate among unvaccinated people
The mortality rate was calculated by considering the time when 90% of the two-dose vaccination administered by December 2021 was achieved. The analysis revealed that about 3500 deaths occurred in 2021 among unvaccinated people who had access to COVID-19 vaccination but refused to receive it because of vaccine hesitancy.
The study further estimated the number of deaths per day per million people in the vaccinated and unvaccinated populations to adjust for the significant size variation between vaccinated and unvaccinated populations. The findings revealed that the death rate is 2-8 times higher in the unvaccinated population compared to that in the vaccinated population.
Predicted hospitalization and mortality rate among unvaccinated people
The prediction analysis was conducted by considering that all of the remaining unvaccinated population in the UK got infected with SARS-CoV-2. The findings revealed that about 29,600 hospitalizations and 11,700 deaths could occur in the future if vaccine-hesitant people remain unvaccinated and contract SARS-CoV-2 infection, especially omicron infection.
Furthermore, the analysis predicted that the number of hospitalizations and deaths could be reduced to 19,500 and 5,300, respectively, if most vaccine-resistant people receive a COVID-19 vaccine.
Study significance
The study findings highlight that hesitancy to COVID-19 vaccination can significantly increase the rate of COVID-19-related hospitalizations and deaths in England. Importantly, the study predicts that the observed severity of COVID-19 could be reduced significantly if the majority of unvaccinated people, who are resistant to COVID-19 vaccination, agree to receive full vaccination.
*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.
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