By Dr. Liji Thomas, MDMay 19 2020
The world has rarely seen such a readily transmissible infection as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) over the last century. Within five months, the virus has created a Tsunami of COVID-19 positive cases, comprising almost 4.88 million people and causing 322,000 deaths.
However, the spread of the virus is slower than expected in Africa. A new study by researchers at Makerere University and the London School of Hygiene & Tropical Medicine and published on the preprint server medRxiv* in May 2020 is focused on finding any possible link between the low risk of infection and parasitic infections.
The Role of Inflammation in Severe COVID-19
The disease manifestations in COVID-19 range from asymptomatic to critically ill requiring mechanical ventilatory support. Severe COVID-19 manifests with a hyperimmune response that is marked by high levels of pro-inflammatory cytokines like IL-6, IL-2, and TNF-α often termed the cytokine storm or cytokine release syndrome. High levels of IL-6 are associated with increased severity of disease in COVID-19. Some studies show that when patients with severe disease are treated with monoclonal antibodies that block the IL-6 signaling pathway, the duration of stay in the intensive care unit (ICU) is shortened, and there is an earlier resolution of disease.
Immunomodulators in Parasitic Infestation
Parasitic infestations are widespread in Africa. Many parasites live for years in their hosts, without producing significant symptoms. This is due to the interplay of immunity vs. tolerance. In other words, sterilizing immunity, or the development of an immune response strong enough to eliminate the pathogen, is rarely achieved. Still, the parasite count and distribution are kept in check, allowing the host to live a mostly healthy life.