ZIMBABWE is a now an epicentre of new Covid-19 strains, which researchers say have worrying mutations, a research paper has shown.
BRIDGET MANANAVIRE
In January, Zimbabwe recorded a 95% prevalence rate of the (B.1.351) variant, originally identified in South Africa, making it the second country other than South Africa to report B.1.351 as the dominant variant to date, according to the paper published in The Lancet Microbe journal.
The variant accounted for 69% in December.
“Prospective surveillance of SARS-CoV-2 by genome sequencing in Zimbabwe between December 2020, and January 2021 (the period of the so-called second wave), has identified that variants with concerning mutations are prevalent in sequenced samples,” the journal read.
In December, out of the 107 sequenced cases, 95 (89%) of them contained mutations of concern, with the number growing to 104 (98%) cases in January 2021.
The identified variants in Zimbabwe included the B.1.351 (501Y.V2) and A.23.1 variants, along with a novel variant under investigation (C.2).1, 2, 3.
“Variants with concerning mutations have all replaced previously identified lineages in Zimbabwe. As in other countries, this variant (B.1.351) has been associated with increased transmissibility, resulting in overwhelmed healthcare systems and in higher mortality than the first wave (appendix),” the journal reads.
“Secondly, the A.23.1 variant of concern, first reported in Uganda, was observed in 3 (3%) of 107 sequenced cases in December, but was not observed in 104 sequenced cases in January. Thirdly, a variant designated C.2 and containing a spike protein mutation (N501T) that was previously reported in another lineage of SARS-CoV-2 found in mink was present in Zimbabwe in both December, 2020, and January, 2021.”
“N501T is thought to improve ACE2 receptor binding in mink.3. A mutation in the same location, N501Y, is associated with increased transmissibility in humans. In December 2020, 18 (15%) of 117 of cases were found to be of the C.2 variant, whereas in January, 2021, this number fell to 3 (3%) of 104. Phylogenetic analysis of international genomes of the C.2 variant indicated that they were interspersed with C.2 genomes from Zimbabwean cases, indicating that Zimbabwe was a possible source.”
The researchers said the observation highlights the importance of global surveillance through whole-genome sequencing of SARS-CoV-2 to identify sources and transmission routes, and to provide supporting evidence for policy decisions.
The Zimbabwean government implemented a Covid-19 lockdown on 3 January, closing all its land borders including the land border that links Zimbabwe and South Africa, Beitbridge, following a spike in cases and deaths, and only relaxed them beginning of March.
As of 14 March, 37 660 people had received the first dose of the Sinopharm vaccine after the launch of the vaccination programme on 18 February. The country received its first batch of 200 000 vaccines from in February and received 344 000 more vaccines from Sinopharm and Sinovac on Tuesday.
The journal paper was authored by local and international researchers including Tapfumanei Mashe, Faustinos Tatenda Takawira, Hlanai Gumbo, Agnes Juru, Charles Nyagupe, Kenneth K Maeka, Sekesai Mtapuri-Zinyowera, Muchaneta Gudza-Mugabe, Leonardo de Oliveira Martins, Justin O’Grady, Robert A Kingsley, Andrew J Page and Raiva Simbi.
Agnes Mahomva, the chief co-ordinator of Zimbabwe’s national response to the Covid-19 pandemic, was not available for comment on the issue as her phones went unanswered.