EPIDEMIOLOGIC MODEL OF DIARRHEAL DISEASES AND ITS APPLICATION IN PREVENTION AND CONTROL

In this paper, a prototype epidemiological model of actue bacterial an d viral diarrhoeal diseases occurring in young children is formulated. The model is able to mimic the observed epidemiological patterns of i nfantile diarrhoeal diseases associated mainly with enterotoxigenic Es cherichia coli or with rotavirus. The proposed mathematical model pred icts a plausible pattern of the serological profile of an enteric infe ction. According to computer simulation experiments (CSE) with this mo del, it is not necessary to develop an enteric vaccine conferring tota l and long-lasting immunity in order to achieve protection from diarrh oeal diseases in young children. Given a protective efficacy and a fin ite duration of vaccine-induced protection, the optimal immunization p olicy must be sought. Oral rehydration therapy (ORT) intervention has a clear effect in diminishing the number of individuals dying from dia rrhoeal illness. The CSE also predict an apparent reduction in age-pre valence of diarrhoeal diseases by use of ORT.