Immuno-epidemiological patterns

Age infection curve:



Human populations in areas with endemic schistosomiasis show a characteristic relation between age and infection level. Infection typically rises rapidly during childhood, peaking at around 8 - 15 years of age and then declining with increasing age. The infection intensity is measured as egg output in faeces or urine.

Peak shift:

A further phenomen has been observed in human schistosomiasis infections, which is called "peak shift". "Peak shift" describes the fact that the peak level of intensity is higher and occurs at a younger age in populations with a higher overall infection intensity when compared with areas of lower infection intensity.The peaks also become more convex at higher levels of overall population infection intensity

Recommended Literature:

Mutapi F. (1998) Chemotherapy accelerates the development of acquired immune responses to Schistosoma haematobium infection. J Infec Dis 178 (1): 289-93. 

Woolhouse ME. (1998). Patterns in parasite epidemiology: the peak shift. Parsitol Today. 14 (10): 428-34. 

Woolhouse ME. (1992). A theoretical framework for the immunoepidemiology of helminth infection. Parsite Immunol. 14 (6): 563-78.