Impact of the COVID-19 Duration on Neglected Parasitic Diseases

The Coronavirus disease-2019 (COVID-19) pandemic, which started in Wuhan, China in December 2019, has affected the whole world and caused approximately four million deaths. Consequently, scientists have done a great deal of research in such a short time about the disease. Meanwhile, parasites, whose evolutionary process is as old as human history, are often underestimated despite their high prevalence and lethality. Recent studies; however, have shown that immunity changes caused by parasitic infections affect the course of viral diseases. For example, because severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and Plasmodium use a common CD147 receptor to enter the cell and have similarities in their MHC-presented antigenic determinants, scientists suggest that immunity against parasitic infections protects the body against SARS-CoV-2 infections. This could explain the low COVID-19 incidence in malaria-endemic countries. Additionally, the cytokine storm, which is responsible for mortality in COVID-19 infections, is caused by the activation of the immune system to Th1 way. On the other hand, helminth infections, which activate the immune system to Th2 way, can reduce mortality by preventing the cytokine storm. The relationship between COVID-19 and parasites is not limited to changes in the immune system changes. Studies have shown that the pause in the fight against parasitic infections due to the diversion of all attention toward COVID-19 since the beginning of the pandemic will lead to an increase in incidences of malaria, leishmaniasis, schistosomiasis, and soil-transmitted helminths. For this reason, efforts to mitigate this increase should be resumed as soon as possible by taking additional measures globally.