COVID-19: Impact in Africa / Prophylactic Intranasal Spray in Ferrets

By Kelly Young

Edited by David G. Fairchild, MD, MPH, and Richard Saitz, MD, MPH, FACP, DFASAM

Here are some of the latest developments on COVID-19:

COVID-19 in Africa: A pair of studies lays out sobering COVID-19 data for Africa, and for Zambia in particular. In The BMJ, researchers collected postmortem nasopharyngeal samples from nearly 400 deceased people in Lusaka, Zambia, from June through September 2020. Permission was granted as next of kin came to collect bodies from the morgue. Between 16% and 19% of the decedents tested positive for SARS-CoV-2, depending on the viral threshold used. Three fourths of these COVID-19 deaths occurred in the community, and none of these were tested for COVID-19 before their deaths. Roughly 10% of the deaths were in children. The authors note that tuberculosis, malnutrition, and HIV/AIDS were common. The authors conclude: "Contradicting the prevailing narrative that [COVID-19] has spared Africa, the disease has had a severe impact in Zambia. How this was missed is largely explained by low testing rates, not by a low prevalence."

B.1.351 in Zambia: Then in MMWR, researchers report that in Zambia, the average number of confirmed COVID-19 cases increased from 44 cases a day in early December to 700 a day in early January, an increase of 16-fold. This came after the B.1.351 variant — first detected in South Africa — was found in Zambia in the latter half of December. The authors write: "Spread of the B.1.351 variant is of public health concern because of the potential for increased transmissibility and, thus, increases in cases, hospitalizations, and deaths. TheB.1.351 variant might be associated with higher viral loads and contains another spike protein mutation (E484K) that might hinder antibody binding,which could blunt naturally developed immunity or reduce vaccine efficacy."

Intranasal spray in ferrets: An intranasal spray with an engineered peptide successfully prevented ferrets from being infected with SARS-CoV-2, according to a study in Science. Researchers developed a lipopeptide to prevent the coronavirus from attaching to the host. Twelve ferrets were given the intranasal spray or a mock preparation daily for 2 days and then cohoused for 24 hours with ferrets that were positive for the virus. All of the untreated ferrets became infected, but none of the treated ferrets did. The authors say that such a SARS-CoV-2-specific lipopeptide could potentially serve as pre-exposure and early post-exposure prophylaxis to limit SARS-CoV-2 transmission in humans.