The significance of parasitic infections in terms of clinical disease: a personal view

Abstract

Throughout the world, infection with parasites is extremely common. Prevalence is highest in the warm countries of the tropics and subtropics, but infection occurs in all climatic zones. The figures usually quoted for the prevalence of specific parasites attain values akin to those used to describe astronomical distances. The World Health Organization (1985) estimated that some 2582 million of the earth's inhabitants live in areas where they risk contracting malaria and that many – in Africa south of the Sahara alone probably 200 million – remain chronically and persistently infected. Estimates for other parasites are similarly impressive; 600 million at risk of infection with schistosomiasis, with some 200 million actually infected; 900 million exposed to lymphatic filarial parasites, with some 90 million currently infected; for onchocerciasis, probably some 40 million cases spread throughout Africa, Central and South America and the Eastern mediterranean. Yet, impressive as these estimates may be, they are dwarfed by those for some intestinal helminths. Recent assessments suggest that 1 person in 4 of the world's population carries Ascaris lumbricoides (Schultz, 1982), while the same proportion is believed to be infected with one or other of the hookworms (Gilman, 1982).

The effect of maternal, umbilical cord and placental malaria parasitaemia on the birthweight of newborns from South-western Cameroon

“…Malaria in pregnancy has serious health consequences, in particular, maternal anaemia, maternal or fetal death, prematurity, intrauterine growth retardation and low birthweight [1,2]. During pregnancy, especially in first pregnancies, women are more susceptible to Plasmodium falciparum infection and experience a higher frequency and density of parasitaemia than nonpregnant women [3,4].…”

Role of DNA-binding antibodies in kidney pathology associated with murine malaria infections

“…An understanding of the mechanisms by which pathology arises in malaria infections is essential for accurate prognosis and treatment of the disease and also for vaccine design. Such an understanding is of particular importance when we consider the kidney pathology of tropical nephrotic syndrome, which is closely associated with Plasmodium malariae infection and results in very high morbidity and mortality (20). Infection with most species of malaria organisms is associated with either acute or chronic forms of nephritis, and a number of studies have documented the extent and form of structural and functional changes that occur within the kidneys during human, simian, and rodent malarial infections (11).…”

Oedema with proteinuria in Gambian children—a descriptive study

“…Many of the other infections associated with renal disease in other African countries are unlikely to play a role in Gambian children. Malaria nephropathy is less likely, given that P. malariae is relatively rare in The Gambia [20], and all children in this study had been vaccinated against hepatitis B virus. Human immunodeficiency virus (HIV) infection is increasingly recognised as a cause of renal disease.…”