A new genetic mapping study of the coronavirus in Africa has shown that, in addition to the Beta variant, three other worrying strains have had wide circulation in the continent. As countries in the region have little infrastructure for testing, the research was able to reveal an as-yet-unknown history of the epidemic there. The authors say the region needs help not to become an exporting center for hypercontagious strains of the virus.
The research results were based on the sequencing of genetic material from 8,746 virus samples collected in 33 countries over the course of a year by a consortium of scientists led by the University of Kwazulu-Natal, Durban. To process and interpret the material, an international task force was set up with scientists from 137 institutions, including Fiocruz and UFMG, in Brazil.
The results of the work are described in an article this week in the journal Science. In the study, scientists announce the findings with concern.
“Although skewed by small sampling numbers and blind spots, the findings highlight that Africa must not be left behind in the response to the pandemic, otherwise it could become a source of new variants,” writes the group, led by South African researcher Eduan Wilkinson.
In the work, the researchers show that, due to the rate of variation that the analyzed samples present among themselves, they keep signs that the virus had wide circulation in the analyzed countries. This confirms the already established impression that the Covid-19 African epidemic is much larger than official figures show.
The study did not produce an estimate of the size of this underreporting, but relied on research with antibody testing to scale the epidemic.
The researchers confirm that the continent has “many” worry variants, in addition to Beta, and can point to at least three of them, designated by the codes B.1.525, A.23.1 and C.1.1, circulated a lot. The countries where they circulated the most were those that acted as the great connection nodes of the epidemic in Africa: Nigeria, Kenya and South Africa.
The analysis of the genetic difference in the viruses captured from Covid-19 patients in different countries also helped to understand the trajectory of the epidemic’s spread across the continent, which was poorly understood due to underreporting.
Covid-19 initially arrived on the continent mainly for passengers on flights from Europe. After the air blockades at the start of the pandemic, this spread even came to a halt, because sub-Saharan Africa has poor transport infrastructure, and countries are poorly connected to each other. “In almost every instance, introductions of Sars-CoV-2 into individual African countries have occurred via non-African countries,” the scientists wrote.
Once Covid-19 managed to reach every major population center in the region, however, it took on a dimension that was difficult to contain. The situation is now greatly aggravated by a “painstakingly slow” vaccination campaign, with less than 1% of the population immunized in most countries.
“This creates an environment in which the virus can replicate and evolve: new strains of concern will almost certainly emerge, and any one of them could derail the global fight against Covid,” write Wilkinson and his co-authors in Science.