Prevalence of Schistosoma mansoni and its clinical relevance at a primary health care level in rural lake zone of Tanzania: a cross sectional study
DOI:
https://doi.org/10.4314/tmj.v28i2.224Keywords:
Schistosoma mansoni, wet mount stool examination, primary health care level, north-western TanzaniaAbstract
Introduction
Intestinal schistosomiasis is still endemic in most countries in sub Saharan Africa including Tanzania. It is associated with unacceptably high morbidity and mortality especially due to its long term complications. These complications could potentially be prevented through early diagnosis and timely treatment of Schistosoma mansoni infection. However, in Lake Zone only a small proportion of patients present to tertiary level hospital in early stages of the disease and schistomal status at primary health care level is not described in Lake Zone. The aim of this study was to determine the prevalence of Schistoma mansoni and its clinical relevance at a primary health care level.
Materials and methods
A cross sectional study including all patients attending Sengerema DDH with abdominal pain and/or diarrhea was done. Their stool samples were examined by routine wet mount preparation and the data of study interest were analyzed including stool sample results, demographic data, clinical symptoms and risks for Schistosomal exposure using stata version 12 to determine the prevalence of Schistosoma mansoni in this study population.
Results
A total of 1255 stool samples were examined parasitologically for presence of intestinal parasites. Most of the study participants were females 783(62.39%) with a mean age of 30 (IQR 2-80) years. Of the 1225 stool samples examined, 561 (44.7%) were parasitologically positive for intestinal parasites where Schistosoma mansoni was recovered in 141 (11.24%) of the study participants being the second most common intestinal parasite after Entamoeba histolytica. Of the positive stool samples Schistosoma mansoni was found in 25.1% of the samples and was strongly associated with a male gender (OR=1.5, p=0.017), age younger than 20 years (OR= 3.4, p<0.001), and being involved in fishing (OR=1.9, p=0.043) and rice pad activities (OR=3.1, p<0.001).
Conclusions
The current study indicates that Schistosoma mansoni transmission still occurs in Lake Zone, however probably the symptoms due to intestinal Schistosoma infections are frequently common among young people. On clinical aspects these findings are important suggesting that transmission of S. mansoni could significantly be reduced by praziquantel (PZQ) mass drug administration (MDA) targeting those at risk including ages below 20years, but this may need a sustained and more regular frequent PZQ doses a year.
References
Chitsulo, L., et al., The global status of schistosomiasis and its control. Acta Trop, 2000. 77(1): p. 41-51.
Steinmann, P., et al., Schistosomiasis and water resources development: systematic review, meta-analysis, and estimates of people at risk. Lancet Infect Dis, 2006. 6(7): p. 411-25.
Ross, A.G., et al., Schistosomiasis. N Engl J Med, 2002. 346(16): p. 1212-20.
Caldas, I.R., et al., Human schistosomiasis mansoni: immune responses during acute and chronic phases of the infection. Acta Trop, 2008. 108(2-3): p. 109-17.
Gray, D.J., et al., Diagnosis and management of schistosomiasis. BMJ, 2011. 342: p. d2651.
WHO, Schistosomiasi. Schistosomiasis, Fact Sheet No 115;, 2016.
Chofle, A.A., et al., Oesophageal varices, schistosomiasis, and mortality among patients admitted with haematemesis in Mwanza, Tanzania: a prospective cohort study. BMC Infect Dis, 2014. 14: p. 303.
Mazigo, Prevalence of intestinal parasitic infections among patients attending Bugando Medical Centre in Mwanza, north-western Tanzania: a retrospective study. Tanzanian Journal of Health Research, 2010. 12 (3 ).
Mazigo, H.D., et al., Epidemiology and control of human schistosomiasis in Tanzania. Parasit Vectors, 2012. 5: p. 274.
Ajanga, A., et al., Schistosoma mansoni in pregnancy and associations with anaemia in northwest Tanzania. Trans R Soc Trop Med Hyg, 2006. 100(1): p. 59-63.
El Scheich, T., et al., Hepatosplenic morbidity due to Schistosoma mansoni in schoolchildren on Ukerewe Island, Tanzania. Parasitol Res, 2012. 110(6): p. 2515-20.
Massa, K., et al., Community perceptions on the community-directed treatment and school-based approaches for the control of schistosomiasis and soil-transmitted helminthiasis among school-age children in Lushoto District, Tanzania. J Biosoc Sci, 2009. 41(1): p. 89-105.
Hodges, M.H., et al., Mass drug administration significantly reduces infection of Schistosoma mansoni and hookworm in school children in the national control program in Sierra Leone. BMC Infect Dis, 2012. 12: p. 16.
Coulibaly, J.T., et al., Efficacy and safety of praziquantel in preschool-aged children in an area co-endemic for Schistosoma mansoni and S. haematobium. PLoS Negl Trop Dis, 2012. 6(12): p. e1917.
King, C.H., et al., Utility of repeated praziquantel dosing in the treatment of schistosomiasis in high-risk communities in Africa: a systematic review. PLoS Negl Trop Dis, 2011. 5(9): p. e1321.
Webster, B.L., et al., Praziquantel treatment of school children from single and mixed infection foci of intestinal and urogenital schistosomiasis along the Senegal River Basin: monitoring treatment success and re-infection patterns. Acta Trop, 2013. 128(2): p. 292-302.
Tchuem Tchuente, L.A., et al., Efficacy of praziquantel and reinfection patterns in single and mixed infection foci for intestinal and urogenital schistosomiasis in Cameroon. Acta Trop, 2013. 128(2): p. 275-83.
Sesay, S., et al., Schistosoma mansoni infection after three years of mass drug administration in Sierra Leone. Parasit Vectors, 2014. 7: p. 14.
Dunne, D.W., et al., Human IgE responses to Schistosoma mansoni and resistance to reinfection. Mem Inst Oswaldo Cruz, 1992. 87 Suppl 4: p. 99-103.
Ribeiro de Jesus, A., et al., Human immune responses to Schistosoma mansoni vaccine candidate antigens. Infect Immun, 2000. 68(5): p. 2797-803.
de Jesus, A.M., et al., Correlation between cell-mediated immunity and degree of infection in subjects living in an endemic area of schistosomiasis. Eur J Immunol, 1993. 23(1): p. 152-8.
Dunne, D.W., et al., Immunity after treatment of human schistosomiasis: association between IgE antibodies to adult worm antigens and resistance to reinfection. Eur J Immunol, 1992. 22(6): p. 1483-94.
Black, C.L., et al., Influence of exposure history on the immunology and development of resistance to human Schistosomiasis mansoni. PLoS Negl Trop Dis, 2010. 4(3): p. e637.
Karanja, D.M., et al., Resistance to reinfection with Schistosoma mansoni in occupationally exposed adults and effect of HIV-1 co-infection on susceptibility to schistosomiasis: a longitudinal study. Lancet, 2002. 360(9333): p. 592-6.
Kabatereine, N.B., et al., Adult resistance to schistosomiasis mansoni: age-dependence of reinfection remains constant in communities with diverse exposure patterns. Parasitology, 1999. 118 ( Pt 1): p. 101-5.
Fulford, A.J., et al., A statistical approach to schistosome population dynamics and estimation of the life-span of Schistosoma mansoni in man. Parasitology, 1995. 110 ( Pt 3): p. 307-16.
Warren, K.S., et al., Schistosomiasis mansoni in Yemeni in California: duration of infection, presence of disease, therapeutic management. Am J Trop Med Hyg, 1974. 23(5): p. 902-9.
Fitzsimmons, C.M., et al., Human IgE response to the Schistosoma haematobium 22.6 kDa antigen. Parasite Immunol, 2004. 26(8-9): p. 371-6.
Joseph, S., et al., Increases in human T helper 2 cytokine responses to Schistosoma mansoni worm and worm-tegument antigens are induced by treatment with praziquantel. J Infect Dis, 2004. 190(4): p. 835-42.
Woolhouse, M.E. and P. Hagan, Seeking the ghost of worms past. Nat Med, 1999. 5(11): p. 1225-7.
Yimer, M., et al., Evaluation performance of diagnostic methods of intestinal parasitosis in school age children in Ethiopia. BMC Res Notes, 2015. 8: p. 820.
Florah Bukindu, D.M., Humphrey D. Mazigo, Prevalence of Schistosoma mansoni and soil transmitted helminths and factors associated with uptake of preventive chemotherapy among school children in Sengerema District in north-western Tanzania. Tanzania Journal of Health Research 2016. 18(1).