Is multiple sclerosis caused by a silent infection with malarial parasites? A historico-epidemiological approach: part I.

Though many details are known about the epidemiology of multiple sclerosis (MS), its aetiology has remained an enigma. To find a solution to this problem, the concept of so called 'anophelism without malaria' was put on trial. 'Anophelism without malaria' is a basic assumption of the epidemiology of malaria. It means that there is no transmission of malaria in the temperate zone, although the insect vector (the different species of anopheles) can be found nearly everywhere. Starting with the results from blood tests of five patients suffering from MS which indicate an infection with plasmodia, the old hypothesis of the malarial aetiology of MS (Mannaberg 1899) is reappraised and compared with today's pathological findings. A comparison of the old map of malaria with the later distribution of MS in the USA has been made, supporting the assumption that an infection with plasmodia in early childhood prevents a later disease, while a silent infection at the time of adolescence or later is its cause.