A new study estimates that COVID-19 vaccines helped avert
19.8 million deaths across the globe during the first year after vaccination
campaigns were initiated.
The study found that vaccine inequity resulted in a disproportionately
higher number of deaths prevented by vaccination in high-income nations than in
lower-income nations.
Several low-income nations failed to meet the World Health
Organization (WHO) target of vaccinating 40% of their populations and achieving
this target could have doubled the number of lives saved in those regions.
A recent study published in the journal Lancet Infectious
DiseaseTrusted Source estimates that COVID-19 vaccines helped reduce the global
death toll by 63% during the first year they became available. The study also
found that a more equitable distribution of COVID-19 vaccines could have
prevented a significant number of deaths in low-income nations.
Dr. Oliver Watson, a researcher at Imperial College London,
said, “Our findings offer the most complete assessment to date of the
remarkable global impact that vaccination has had on the COVID-19 pandemic. […]
Our findings show that millions of lives have likely been saved by making
vaccines available to people everywhere, regardless of their wealth.”
“However, more could have been done. If the targets set out
by the WHO had been achieved, we estimate that roughly 1 in 5 of the estimated
lives lost due to COVID-19 in low-income countries could have been prevented,”
he added. Impact of COVID-19 vaccines
The first dose of a COVID-19 vaccine was delivered outside a
clinical trial setting on December 8, 2020.
Since the approval of the first COVID-19 vaccine, nearly 62%
of the global population has been fully vaccinated with two doses of the
vaccine.
The approved COVID-19 vaccines are highly effective in
preventing severe disease and reducing mortality and have changed the
trajectory of the pandemic. Studies examining the impact of COVID vaccines in
reducing mortality so far have been restricted to specific regions and have
only assessed the direct effects of vaccination in preventing deaths in
individuals.
Researchers at Imperial College London recently assessed the
global impact of COVID-19 vaccination by quantifying the deaths prevented by
these vaccines during the first year of vaccination.
In addition to the direct effects of vaccines on mortality,
the researchers also accounted for the indirect benefits conferred by vaccines
such as reducing the transmission of the virus in the community, including
unvaccinated individuals. Quantifying the lives saved
The researchers used mathematical models of SARS-CoV-2
transmission to estimate the number of lives that would have been lost in an
alternative scenario involving the lack of COVID-19 vaccines.
They incorporated data on variables such as vaccination
rates, vaccine rollout dates, COVID-19 deaths, variants in circulation, and
demographic data for each country in the model to arrive at estimates of deaths
averted due to vaccination.
Based on the number of COVID-19 deaths officially reported
by each country, the researchers estimated that vaccines helped prevent 14.4
million deaths across the globe during the first year of COVID-19 vaccination.
However, studies suggest that official reports have
significantly underestimated the actual number of deaths attributed to
COVID-19.
Hence, the researchers assessed excess all-cause deaths
during the COVID-19 pandemic, which is the difference between the number of
deaths observed during a year of the pandemic and the expected deaths in a
non-pandemic year.
The researchers used national vital registration systems
that maintain records on deaths and births to obtain data on excess deaths due
to COVID-19. However, these registries are incomplete in many developing
countries. Hence, the researchers used models to predict the excess deaths in
these countries.
Based on estimates of excess deaths during the pandemic, the
researchers found that vaccinations helped avert 19.8 million deaths, lowering
the death toll by 63% during the first year of vaccinations.
Global disparities in vaccination rates
Vaccination coverage in low- and middle-income countries has
lagged behind that in high-income countries due to inequities in access to
COVID-19 vaccines.
The COVID Vaccine Global Access (COVAX)Trusted Source
initiative was launched to facilitate more equitable distribution of the
vaccines, including through the donation of vaccines by wealthier nations. The
COVAX initiative’s Advanced Market Committee (AMC) helps finance the purchase
of vaccines and their distribution to low- and middle-income countries.
COVAX AMC had set a target of immunizing 20% of the
population in developing countries by the end of 2021. Likewise, the World
Health Organization had set a target of immunizing 40% of the global population
in the same time period.
However, numerous developing countries failed to reach these
targets. The inadequate vaccine supply and hoarding of vaccine doses by
wealthier countries meant that low-and middle-income countries had limited
access to vaccines.
The lack of necessary infrastructure for the storage of
vaccines and vaccine hesitancy has also contributed to lower vaccination rates
in some nations.
In the present study, the researchers assessed the number of
lives that could have been saved if the distribution of vaccines was more
equitable. They found that the number of deaths prevented due to vaccination
was greater in high-income nations than in low and middle-income nations.
Nevertheless, COVID-19 vaccines reduced the death toll by an
estimated 41% (7.4 million) in 83 COVAX AMC countries. Among these COVAX AMC
participants, 41 countries failed to reach the target of vaccinating 20% of
their population. This included 25 low-income countries and achieving the 20%
vaccination target could have reduced the death toll by an additional 45% in
these countries.
Moreover, 96 countries failed to meet the WHO target of
vaccinating 40% of the population. The majority of these were low-income
countries and achieving the WHO target in those countries could have prevented
more than twice (111%) as many deaths in these countries.
Equitable vaccine distribution
These results highlight the need for mechanisms to achieve a
more equitable distribution of vaccines.
Dr. Ingrid Katz, a professor at Harvard Medical School,
said, “There are many measures that could help achieve global vaccine equity.
At the core of any proposal, we need a strong intergovernmental body that can
help establish a convention or agreement to strengthen pandemic prevention,
preparedness, and response.”
“This must be embedded in global health equity and a
commitment for the international community to work together and ensure the
strengthening of healthcare at the community level. This must be backed by
sustained funding for pandemic preparedness and oversight mechanisms that can
ensure accountability and transparency while ensuring trust,” she said.
