Zablon Kerima: Prevention is so far best weapon against Covid-19
A healthcare worker reacts in pain as she receives a dose of the Johnson & Johnson vaccine against the Covid-19 as South Africa proceeds with its inoculation campaign at the Klerksdorp Hospital on February 18, 2021.
What you need to know:
- As wealthy countries intensify vaccination drives, the lower-income ones are calling for equitable distribution of the vaccines.
- The inequity in vaccine distribution and the development that the virus is mutating to more contagious variants should be a cause for concern.
The global discourse around the Covid-19 pandemic has morphed from prevention to vaccination. As wealthy countries intensify vaccination drives, the lower-income ones are calling for equitable distribution of the vaccines.
Preventive measures like masking, handwashing and social distancing are vital as they stop the coronavirus from gaining access into the body to cause infection.
On the contrary, vaccines do not stop entry of the virus but they greatly reduce chances of suffering severe illness and death following the interaction between the virus and immune system.
With vaccine nationalism at play, it has been projected that most Sub-Saharan African countries will not be fully vaccinated at least until 2023. This prediction should underscore the need for people to bolster their adherence to preventive measures.
Vaccine distribution
The inequity in vaccine distribution and the development that the virus is mutating to more contagious variants should be a cause for concern. A case in point: Kenya has reported a different strain from the ones circulating in South Africa and the UK.
South Africa has suspended the use of the Oxford/AstraZeneca vaccine after it emerged that it was not effective against a variant reported in the country. With global connectivity, the situation could be more disastrous if the strain spreads to countries where the vaccine is already deployed.
The virus does not transform to new strains independently. It has to interact with its host — humans — who, over time, tries to build adaptive immunity, following previous exposure.
In response, the virus undergoes changes in its genetic architecture, generating new strains. These viral strains then adapt to the host’s defence mechanism, overcoming it to mount an infection.
Emergence of new strains
Therefore, the longer the virus is exposed to human populations where preventive measures are not adhered to or vaccine coverage is limited, the more rapid the emergence of new strains.
The strains could, gradually, hinder the efficiency of vaccines, resulting in more infections and deaths in vaccinated and less-vaccinated countries alike.
It makes sense to be proactive by being smarter than the virus. This needs thorough understanding of the virus’s genetic constitution to anticipate the nature of new strains before they emerge. This is how scientists have been able to develop yearly flu shot vaccines against seasonal influenza virus, which keeps mutating rapidly.
With the novel coronavirus, however, scientists cannot afford the opportunity to develop a second generation of Covid-19 vaccines to tame new variants when the production — let alone distribution — of enough doses of the first generation that target the original strain is still a herculean task.
To this end, strict adherence to preventive measures remains the suitable approach to deny the virus and its variants an opportunity to cause infection.
Dr Kerima (PhD) is a biochemist. [email protected]. @KerimaZablon
