Paleoparasitology and human evolution

Understanding various aspects of transmission of infectious diseases, including the parasitic, has been simplified in recent times by the application of multiple technological tools available. The origin and subsequent transmission of these pathogens in the ancient world and their relation to human evolution have revealed some interesting information. Human parasites, particularly helminths, have been found to be most useful in these studies since their eggs can survive for thousands of years in special environments and reveal the genus or species of the parasite. The new field of research and subject discipline of Paleoparasitology has come into existence, which is the study of parasites in ancient material. The finding of eggs and genetic material in the preserved humans in mummies or in frozen conditions or in animal fossils has facilitated a lot to trace the source and evolution of some of the parasites and follow human migration from its ancestral African origin. According to available evidence, parasites such as Enterobius vermicularis and Trichuris spp and the ectoparasite, such as Pediculus humanus, all of which had their origin inhuman ancestors in Africa and then spread to other parts of the world due to human migration. They have been named as “heirloom parasites.” On the other hand, some other parasite, such as Paragonimus spp. was acquired by humans after they left Africa and during their onward travels. Such parasites have been named as “souvenir parasites” in the way we pick up exotic items during our travels to new places. Interested readers can get more information in this interesting topic in some of the excellent reviews by Araújo et al.,^[1] Mitchell,^[2] Kliks,^[3] and other cross references.

The present issue of Tropical Parasitology opens with the Presidential oration^[4] where the new horizon of Deep Technology and Artificial Intelligence as applied to Parasitology has been explored. The review article focuses on cardiac manifestations of parasitic diseases, where a wealth of information on this topic is provided.^[5] Of the seven original research articles, three deal with different aspects of malaria and malaria parasites. One article is about the deletion of hrp2 and 3 genes in clinical isolates of Plasmodium falciparum which will cause false-negative results in rapid malaria antigen tests.^[6] A systematic review of malaria case reports during COVID-19 and features of the disease^[7] and a 7 years trend analysis of malaria from Puducherry, India^[8] are the other two malaria-related articles. A 6 years study from Senegal, Africa, details the seroprevalence of toxoplasmosis and rubella infection in one original article^[9] while another article from Egypt describes the morbidity markers among Schistosoma mansoni patients.^[10]Blastocystis remains an enigmatic parasite and its presence, along with pathological and clinical findings, features in a well-designed study from Egypt.^[11] The other original article is a bioinformatics study that explores various peptides of Echinococcus granulosus for their immunogenicity with possible future application in vaccine development and design of diagnostic tests.^[12] In the dispatches section, there is one report of ticks causing blepharitis,^[13] and another dispatch describes intraocular cysticercosis in a patient with neurocysticercosis.^[14] In the regular face-to-face section, E-mail interview with Prof. Shyam Sunadar^[15] is featured, who has contributed immensely to clinical aspects of visceral leishmaniasis in India and is considered an authority on Kala-Azar.

It is hoped that articles in this issue will make an interesting reading.