Polymorphism and virulence factors in the pathogenesis of amoebiasis

Amoebiasis is one of the world's most prevalent infectious diseases of developing world. E. histolytica and E. dispar are two morphologically identical but genetically distinct species. Infection with E. histolytica may be symptomatic and asymptomatic. E. dispar is non-pathogenic. Both innate and acquired immune responses limit amoebic infection while different strains of E. histolytica and its virulence have been described and virulence factors of E. histolytica such as cysteine proteinases; Gal/GalNAc-inhibitable lectin and ameobapore are known to be involved in E.histolytica pathogenesis. Proteolytic enzymes and cysteine proteases facilitate tissue invasion while Gal/GalNAc-inhibitable lectin aids adherence and amoebapores are involved in lysis of target cells. Three new strains of E. histolytica (Rahman; HK-9; and 200: NIH) have been described as well as the previously known strain (HM 1 IMSS). This review highlights the newly described strains and virulent factors involved in the pathogenesis of E. histolytica

Factors that facilitate infant survival in a low socio-economic community in Lagos State, Nigeria

Infants are delicate, relying mostly on caregivers for their survival. Their survival is plagued by diseases, poverty, behavioural habits and cultural beliefs of the caregivers in the developing countries. For strategies to improve infant survival, the health seeking behaviour and home care practices of caregivers during infant illness episodes were studied. A total of 742 caregivers in 5 out of 11 health districts of Ajeromi/Ifelodun Local Government areas of Lagos State whose infants were ill four weeks preceding the survey were interviewed using a semi-structured questionnaire. Sixty-two (8.4%) of the interviewed lost their infants; 51.6% of children who died did so in hospitals, 35.5% at home and 12.9% at unspecified places. The notable causes of death were malaria (22.6%), acute respiratory infections (14.5%) and diarrhea (12.9%). Majority of the caregivers (60.0%) whose infants died did not seek external help until 24hrs or more after onset of illness signs. Infant's tendency to survive an illness episode was significantly dependent on full term delivery (P<0.01); birth weight (P<0.01); treatment sources (P<0.05) and infant feeding methods (P<0.05). Appropriate antenatal care and infant feeding practices including exclusive breast feeding, early recognition of danger signs and timely health seeking will significantly improve child survival in Nigeria