A review of the control of schistosomiasis in South Africa

Magaisa K, Taylor M, Kjetland EF, Naidoo PJ Download publication Schistosomiasis is the second most important tropical disease in the world in terms of public health impact. In South Africa, more than 4 million people are estimated to be infected with schistosomiasis. School-age children usually have the highest prevalence and intensity of infection. Schistosoma haematobium may result in female genital schistosomiasis which presents as inflammation and ulceration of the genital mucosa and pathological blood vessels. These effects may increase the susceptibility of women with female genital schistosomiasis to HIV. Praziquantel is the drug used to treat schistosomiasis and it is best to treat people during the early stages of infection, before female genital schistosomiasis presents as lesions and sandy patches, as there currently is no treatment for these symptoms. Schistosomiasis is not regarded as a serious public health issue in South Africa despite evidence revealing the seriousness of the disease. In areas endemic for schistosomiasis, the World Health Organization recommends regular mass treatment of all school-age children. In 2001, South Africa became a signatory to the World Health Assembly resolution 54.19 which urged all member states to achieve the minimum goal of 75% treatment coverage in school-age children at risk by 2010. This goal has not been achieved in South Africa, despite efforts made by the Department of Health, such as the first statutory school-based geohelminth control programme in the province of KwaZulu-Natal. However, this programme has not been continued. Therefore, there is still much work to be done in order to control and decrease the prevalence of schistosomiasis in endemic...

The First Step Toward Diagnosing Female Genital Schistosomiasis by Computer Image Analysis

Holmen SD, Kleppa E, Lillebø K, Pillay P, van Lieshout L, Taylor M, Albregtsen F, Vennervald BJ, Onsrud M, Kjetland EF Journal title: The American journal of tropical medicine and hygiene Am. J. Trop. Med. Hyg. 2015 Apr; PMID: 25918212 Article on PubMed: http://www.ncbi.nlm.nih.gov/pubmed/25918212 Abstract Schistosoma haematobium causes female genital schistosomiasis (FGS), which is a poverty-related disease in sub-Saharan Africa. Furthermore, it is co-endemic with human immunodeficiency virus (HIV), and biopsies from genital lesions may expose the individual to increased risk of HIV infection. However, microscopy of urine and hematuria are nonspecific and insensitive predictors of FGS and gynecological investigation requires extensive training. Safe and affordable diagnostic methods are needed. We explore a novel method of diagnosing FGS using computer color analysis of colposcopic images. In a cross-sectional study on young women in an endemic area, we found strong associations between the output from the computer color analysis and both clinical diagnosis (odds ratio [OR] = 5.97, P < 0.001) and urine microscopy for schistosomiasis (OR = 3.52, P = 0.004). Finally, using latent class statistics, we estimate that the computer color analysis yields a sensitivity of 80.5% and a specificity of 66.2% for the diagnosis of FGS....

Schistosoma haematobium infection and CD4+ T-cell levels: a cross-sectional study of young South African women

Kleppa E, Klinge KF, Galaphaththi-Arachchige HN, Holmen SD, Lillebø K, Onsrud M, Gundersen SG, Taylor M, Ndhlovu P, Kjetland EF Journal title: PloS one PLoS ONE 2015;10(3):e0119326 PMID: 25768005 Article on PubMed: http://www.ncbi.nlm.nih.gov/pubmed/25768005 Abstract Schistosoma (S.) haematobium causes urogenital schistosomiasis and has been hypothesized to adversely impact HIV transmission and progression. On the other hand it has been hypothesized that HIV could influence the manifestations of schistosomiasis. In this cross-sectional study, we explored the association between urogenital S. haematobium infection and CD4 cell counts in 792 female high-school students from randomly selected schools in rural KwaZulu-Natal, South Africa. We also investigated the association between low CD4 cell counts in HIV positive women and the number of excreted schistosome eggs in urine. Sixteen percent were HIV positive and 31% had signs of urogenital schistosomiasis (as determined by genital sandy patches and / or abnormal blood vessels on ectocervix / vagina by colposcopy or presence of eggs in urine). After stratifying for HIV status, participants with and without urogenital schistosomiasis had similar CD4 cell counts. Furthermore, there was no significant difference in prevalence of urogenital schistosomiasis in HIV positive women with low and high CD4 cell counts. There was no significant difference in the number of eggs excreted in urine when comparing HIV positive and HIV negative women. Our findings indicate that urogenital schistosomiasis do not influence the number of circulating CD4 cells....

Gynecological Manifestations, Histopathological Findings, and Schistosoma-Specific Polymerase Chain Reaction Results Among Women With Schistosoma haematobium Infection: A Cross-sectional Study in Madagascar

Randrianasolo BS, Jourdan PM, Ravoniarimbinina P, Ramarokoto CE, Rakotomanana F, Ravaoalimalala VE, Gundersen SG, Feldmeier H, Vennervald BJ, van Lieshout L, Roald B, Leutscher P, Kjetland EF Journal title: The Journal of infectious diseases J. Infect. Dis. 2015 Feb; PMID: 25725656 Article on PubMed: http://www.ncbi.nlm.nih.gov/pubmed/25725656 Abstract BACKGROUND:  The pathophysiology of female genital schistosomiasis (FGS) is only partially understood. This study aims to describe the histopathological findings, polymerase chain reaction (PCR) results, and gynecological manifestations of FGS in women with different intensities of Schistosoma haematobium infection. METHODS:  Women aged 15-35 years living in an S. haematobium-endemic area in Madagascar underwent pelvic and colposcopic examinations. Small biopsy specimens were obtained from lesions and examined histopathologically. Schistosoma PCR was done on urine, biopsy, cervicovaginal lavage, and genital mucosal surface specimens. RESULTS:  Sandy patches and rubbery papules were found in 41 of 118 women (35%). Rubbery papules reflected an intense cellular immune reaction dominated by eosinophils, epithelial erosion, and viable ova. There was a significant decrease in the prevalence of rubbery papules with age, even after adjustment for urinary ova excretion. The sandy patches with grains showed moderate cellular immune reaction and ova (viable and/or calcified). They were most prevalent in cases with low-intensity urinary S. haematobium infection. Forty-two percent of women with Schistosoma-negative urine specimens had at least 1 genital specimen test positive for Schistosoma by PCR. CONCLUSIONS:  The results indicate a diversity of lesions caused by S. haematobium and a dynamic evolution of the genital lesions. Schistosoma PCR may give an indication of the diagnosis....

Colourimetric image analysis as a diagnostic tool in female genital schistosomiasis

Holmen SD, Kjetland EF, Taylor M, Kleppa E, Lillebø K, Gundersen SG, Onsrud M, Albregtsen F Journal title: Medical engineering & physics Med Eng Phys 2015 Mar;37(3):309-14 PMID: 25630808 Article on PubMed: http://www.ncbi.nlm.nih.gov/pubmed/25630808 Abstract Female genital schistosomiasis (FGS) is a highly prevalent waterborne disease in some of the poorest areas of sub-Saharan Africa. Reliable and affordable diagnostics are unavailable. We explored colourimetric image analysis to identify the characteristic, yellow lesions caused by FGS. We found that the method may yield a sensitivity of 83% and a specificity of 73% in colposcopic images. The accuracy was also explored in images of simulated inferior quality, to assess the possibility of implementing such a method in simple, electronic devices. This represents the first step towards developing a safe and affordable aid in clinical diagnosis, allowing for a point-of-care approach....

Schistosoma haematobium infection and asymptomatic bacteriuria in young South African females

Kildemoes AO, Kjetland EF, Zulu SG, Taylor M, Vennervald BJ Journal title: Acta tropica Acta Trop. 2015 Apr;144:19-23 PMID: 25623258 Article on PubMed: http://www.ncbi.nlm.nih.gov/pubmed/25623258 Abstract Schistosoma haematobium eggs can induce lesions in the urinary and genital tract epithelia, as eggs pass through or get trapped in the tissue. Local inflammatory reactions induced by S. haematobium eggs might affect the ability of bacteria to establish mucosal super-infection foci. S. haematobium infection and asymptomatic bacteriuria can both portray haematuria, proteinuria and leukocyturia. This shared set of proxy diagnostic markers could fuel routine misdiagnosis in S. haematobium endemic areas. Furthermore, S. haematobium infected individuals might be at a higher risk of contracting bacterial urinary tract infections, which could manifest either as symptomatic or asymptomatic bacteriuria. The aim of the current study was to explore whether schistosomal lesions are susceptible to super-infection by bacteria measured as asymptomatic bacteriuria. S. haematobium infection was determined by microscopy of urine samples. Furthermore, urine samples were tested with dipslides for asymptomatic bacteriuria and with dipsticks for haematuria, proteinuria and leukocytes. We found no association between asymptomatic bacteriuria and S. haematobium infection in a sample of 1040 female primary and high school students from a schistosomiasis endemic area in KwaZulu-Natal, South Africa. Furthermore, it was demonstrated that asymptomatic bacteriuria is not a bias for use of micro-haematuria as a proxy diagnostic measure for S. haematobium infection in this population....