Human Schistosomiasis, And Nigerian Environment And Climate Change

Human schistosomiasis, commonly called “bilharziasis” after a German pathologist, Theodor Bilharz (who first discovered the parasitic agent in Egypt in 1851) is caused by parasitic trematode of the genus, Schistosoma. There are at least 19 varieties of schistosomes, of which five are pathogenic parasites of man: S. haematobium, S. mansoni, S. japonicum, S. intercalatum and S. marteei (WHO, 1985). There are two types of human schistosomiasis in Nigeria: urinary schistosomiasis caused by infection of S. haematobium and intestinal schistosomiasis caused by the infection of S. mansoni. Different species of freshwater snail which breed in rivers, streams, lakes (both natural and man-made), ditches, paddy field, irrigation, canals etc are the intermediate hosts. The snail intermediate host of S. haematobium is Bulinus while the intermediate hosts of S. mansoni belong to the genus Biomphalaria. Human infection occurs when cercariae (that emerged from the nail intermediate hosts) penetrate the skin of man exposed to contaminated water. In man, the clinico-pathological damage caused by schistosomiasis is serious and is related to the reaction of the host tissues to the migrating young worms, the eggs laid by the adult worms, and the number of schistosomes eggs trapped in the tissues. Details of these have been presented by Odeku et al (1968). Makenna et al (1997), Elem (1998), Udonsi (1999), Anosike et al (2002). Bio-Research Vol.2(1) 2004: 103-11

Investing in justice: ethics, evidence, and the eradication investment cases for lymphatic filariasis and onchocerciasis

It has been suggested that initiatives to eradicate specific communicable diseases need to be informed by eradication investment cases to assess the feasibility, costs, and consequences of eradication compared with elimination or control. A methodological challenge of eradication investment cases is how to account for the ethical importance of the benefits, burdens, and distributions thereof that are salient in people's experiences of the diseases and related interventions but are not assessed in traditional approaches to health and economic evaluation. We have offered a method of ethical analysis grounded in theories of social justice. We have described the method and its philosophical rationale and illustrated its use in application to eradication investment cases for lymphatic filariasis and onchocerciasis, 2 neglected tropical diseases that are candidates for eradication