Now, more than a year after the World Health Organization (WHO) announced the start of the COVID-19 pandemic, we are beginning to expect a reduced spread of the virus. With the release of several effective vaccines and the implementation of safety measures, such as travel bans and quarantine, coronavirus cases are declining in some parts of the world.
Will it be possible to eliminate COVID-19 at some point in the future or will it always remain endemic in some regions? We asked eight epidemiologists if COVID-19 would become endemic – 75 percent said yes.
What does endemic mean?
Endemic “means that there are always people who are infected who transmit the infection to someone else and then recover. For a long time, each person infects another person on average, so the number of infected remains roughly the same,”
This is very different from the high level of transmission we observed during the pandemic.
Many common diseases are endemic, including coronaviruses, which cause colds. Prof. Medley says, “Endemic infections are usually in children causing mild symptoms. Endemic coronaviruses are not associated with significant disease. As children grow older, they will be exposed and potentially infected many times and immunized.”
How did the previous pandemics end?
Professor James Wood, an expert in disease modeling and epidemiology at the University of New South Wales (UNSW) in Sydney, said: “When pH1N12009 (swine flu) appeared in 2009, it became endemic within a year of the initial pandemic. and also pushed an existing influenza strain H1N1 circulating in humans to extinction. “
Many viruses responsible for previous pandemics, including the 1918 flu pandemic, are still circulating today.
Completely eradicating the disease is not easy. To date, the WHO has declared only two diseases that have been eradicated worldwide: smallpox and rinderpest. Both needed a large-scale vaccine campaign around the world to reach herd immunity.
The two options for how the pandemic could end: either the virus is destroyed or it becomes endemic.
Can we eliminate COVID-19 using the new vaccines?
Smallpox and rinderpest have been eradicated with vaccines; now that there are several vaccines against COVID-19, could we use them to eradicate this disease?
Dr. Lee Riley of UC Berkeley highlights a key obstacle to eliminating COVID – the responsible virus can mutate to become resistant to vaccines.
He says that “in places where there is a mixture of vaccinated and unvaccinated populations, vaccines can put selective pressure on the virus to undergo further mutations and these variants will spread among unvaccinated people. Some of the variants can also infect vaccinated people. “.
Another difficulty in achieving herd immunity is that some of the currently available vaccines do not offer 100% immunity against COVID-19.
Professor Jane Heffernan, an epidemiology expert at York University, said: “Infection and vaccination with COVID-19 can cause high levels of protective immunity in humans. Acquired immunity can prevent infection or, if infected, reduce the severity of the disease “.
There is also the challenge of vaccinating so many people in so many countries.
Professor Wood of UNSW emphasizes that “the limitations in our ability to produce vaccines (15-20 million doses per day) mean that high global coverage with 2 doses will take much more than a year, even with a relatively even supply of vaccines.”
Dr David Hayman of Massey University added that “there is a huge inequality in the distribution of vaccines, with only a few percent of the world currently vaccinated. This means that if this is not allowed, the virus is likely to become endemic in those countries.” “
Despite these challenges, in theory, enough of the world’s population could still be vaccinated to reach herd immunity and destroy COVID-19.
Interestingly, however, Professor Wood points out that “elimination and eradication may not remain priorities if the residual protection against vaccines against serious diseases remains strong.”
If we can protect people from severe disease with COVID-19, there may be no reason to eradicate it completely.
Although public health measures and vaccine campaigns will hope to end the current COVID-19 pandemic, it is likely to remain endemic in some countries instead of being completely eradicated.
Article based on 8 expert answers to this question: Will COVID-19 become endemic?
This expert response was published in partnership with the independent fact-finding platform Metafact.io. Subscribe to their weekly newsletter here.