Current trends in the epidemiology and management of enteric fever in Africa: A literature review

Abstract

Enteric fever remains a tropical disease of public health significance in Africa, due to its high endemicity and transmission rates, more in sub-Saharan Africa with 7.2 million cases of typhoid fever annually and incidence rate of 762 per 100 000 person-years when compared with Northern Africa with a reported incidence rate of 557 per 100 000 person-years and lower. Recent studies show that almost all regions of sub-Saharan Africa are tending towards high incidence rates, especially Central and Western Africa. Though clinically indistinguishable from paratyphoid fever, typhoid fever causes more morbidity and mortality than paratyphoid fever, with a greater threat to children. Risk factors include consumption of contaminated water, patronizing food vendors and a history of contact with a case or a chronic carrier, amongst others. Environmental factors such as the rainy season, open sewers, contaminated water bodies and areas of low elevation have been implicated. Diagnosis in Africa is challenging due to resource constraints, as many centres still depend on clinical diagnosis and serodiagnosis using Widal test, in an era where more sensitive and specific tests exist. The polymerase chain reaction is one of the most sensitive diagnostic methods, while culture (particularly bone marrow) is considered to be one of the most specific. Quinolones (ciprofloxacin) and third-generation cephalosporins, amongst others, remain potent in the management of enteric fever, with resistance to quinolones gradually on the rise. Poor diagnostics, poor antibiotic stewardship and lack of drug (antibiotic) regulation are contributors to the problem of antibiotic resistance in Africa. Prevention of typhoid fever through vaccination, especially in children is still under investigation, with steady progress being documented. Overall, long term prevention strategies for typhoid fever should be based on improved sources of drinking water, good sanitation and hygiene, food safety and poverty alleviation.