Takafira Mduluza

Background/Objectives: Intestinal schistosomiasis caused by Schistosoma mansoni is often underestimated in low-transmission settings due to the limited sensitivity of traditional stool microscopy. More sensitive approaches, including antigen detection and molecular diagnostics, are required to detect infections where egg excretion is low or intermittent. This study aimed to determine the prevalence of S. mansoni infection among school-going children in Nelson Mandela Bay (NMB) using a multi-modal diagnostic approach. Methods: This cross-sectional study included 759 schoolchildren aged 5–14 years from 15 primary schools in NMB. Stool samples were analyzed using the Kato–Katz technique to detect S. mansoni eggs, while urine samples were tested using the point-of-care circulating cathodic antigen (POC-CCA) assay for antigen detection. A subset of stool samples from POC-CCA-positive participants (n = 28) was further analyzed using conventional PCR (cPCR), targeting the S. mansoni cox1 gene, for molecular confirmation. Only a single stool specimen was collected per participant. Results: Among the 759 participants (58% male, 42% female), no egg-positive cases were detected. However, POC-CCA testing identified S. mansoni antigen in 3.2% of participants. Of the 28 POC-CCA-positive samples analyzed by cPCR, 9 (32.1%) were PCR-positive, representing molecular confirmation within the antigen-positive subset rather than overall prevalence. Conclusions: Traditional microscopy underestimated S. mansoni prevalence in this low-prevalence setting. Antigen detection combined with molecular diagnostics improved case identification and highlighted ongoing transmission. These findings support the integration of sensitive diagnostic tools into schistosomiasis surveillance and control strategies in South Africa.

Background: Schistosomiasis is known to affect the cognitive functions of children, however, but there is paucity of information on its impact on early childhood development in developing countries where the disease is endemic. This study aimed at determining the effects of schistosomiasis due to Schistosoma haematobium on early childhood development in children below 5 years old from Murewa District, Zimbabwe, including the benefits of treatment. Methods: Preschool age children (PSAC) under the age of 5 years were screened at baseline and at 6 months post-treatment for S. haematobium infections diagnosed using the urine filtration method. Cognitive domains were assessed using the Griffith Mental Developmental Scales III on 136 PSAC. Multivariate logistic regression was used to determine the level of association between S. haematobium infection and performance in the cognitive domains adjusting for confounding factors (i.e. nutrition, hemoglobin levels, gender and age). Median Development Quotient scores of each cognitive domain at baseline and at 6 months post-treatment were compared and quantified. Results: After adjusting for confounding factors, PSAC infected with S. haematobium had greater odds of having lower scores in the Foundation of Learning Domain (OR = 3.9, p = 0.008), Language and Communication Domain (OR = 3.2, p = 0.017), Eye-Hand Coordination Domains (OR = 10.7, p = 0.001), Personal-Social-Emotional Domain (19.3, p = 0.001) and in the Overall General Development Domain (7.2, p = 0.011). Improvement of cognitive performance was observed at 6 months post treatment in the following Domains; Language and Communication Domain (p = 0.003), Eye-Hand Coordination Domain (p = 0.02) and General Development Domain (p = 0.006). Conclusion: The study showed that S. haematobium infection in PSAC is associated with lower cognitive scores in the Foundation of Learning, Language and Communication, Eye-Hand Coordination, Personal-Social-Emotional and in the Overall General Development domains. Our results strengthen the call for inclusion of PSAC in routine deworming programs for the control of urinary schistosomiasis and the need to develop locally validated tools to monitor early child development in endemic areas where resources are limited.

Introduction: Pneumonia is the biggest child killer, after the neonatal period. This is especially so in children from developing countries who are exposed to other infections simultaneously. In this article we investigated the impact of indolent Schistosoma haematobium infection on background of a respiratory infection Method: A cross sectional study with 237 preschool age children with a respiratory infection, was performed during winter months in a schistosomiasis endemic area. Participants were clinically examined and investigated appropriately. Upper respiratory tract infection (URTI) and pneumonia were defined and classified as per IMCI and WHO guidelines, respectively. S. haematobium infection diagnosis was by urine filtration on urine collected over three consecutive days. Data was analysed using SPSS. Results: S haematobium infection prevalence was 29% (69). Prevalence of repiratory infections were as follows: common cold 79% (188), pneumonia 15% (36) and severe pneumonia 6% (15). Eighty-one percent of participants with the common cold were S. haematobium negative, whilst 80 % of those with severe pneumonia were infected. Schistosomiasis infected children were at greater odds of developing; pneumonia (aOR=3.61 (95% CI 1.73-7.55) and severe pneumonia (aOR=21.13 (95% CI 4.65-95.89). High intensity S. haematobium infection was associated with an increased risk of severe pneumonia RR= 23.78(95% CI 6.86-82.32). Mortality from coinfection emanated from severe pneumonia and severe S. haematobium infection intensity (RR= 26.56 (95% CI 1.49 to 473.89). Number needed to harm (NNH) for S. haematobium infected children who develop respiratory tract infection was 4:1 for pneumonia and 5:1 for severe pneumonia. Conclusion: The study demonstrated that coinfection with Schistosomiasis increases morbidity and mortality from respiratory tract infections by up to 20 times in children less than five years old. There is need to cover schistosomiasis screening and treatment in children under 5 years old to avert mortality and morbidity due to coinfection with respiratory infections.

Background: Individuals living in Schistosoma haematobium endemic areas are often at risk of having other communicable diseases simultaneously. This usually creates diagnostic difficulties leading to misdiagnosis and overlooking of schistosomiasis infection. In this study we investigated the prevalence and severity of coinfections in pre-school age children and further investigated associations between S. haematobium prevalence and under 5 mortality. Methods: A community based cross-sectional survey was conducted in Shamva District, Zimbabwe. Using random selection, 465 preschool age children (1–5 years of age) were enrolled through clinical examination by two independent clinicians for the following top morbidity causing conditions: respiratory tract infections, dermatophytosis, malaria and fever of unknown origin. The conditions and their severe sequels were diagnosed as per approved WHO standards. S. haematobium infection was diagnosed by urine filtration and the children were screened for conditions common in the study area which included HIV, tuberculosis, malnutrition and typhoid. Data was analysed using univariate and multinomial regression analysis and relative risk (RR) calculated. Results: Prevalence of S. haematobium was 35% (145). The clinical conditions assessed had the following prevalence in the study population: upper respiratory tract infection 40% (229), fever of unknown origin 45% (189), dermatophytosis 18% and malaria 18% (75). The odds of co-infections observed with S. haematobium infection were: upper respiratory tract infection aOR = 1.22 (95% CI 0.80 to 1.87), dermatophytosis aOR = 4.79 (95% CI 2.78 to 8.25), fever of unknown origin aOR = 10.63 (95% CI 6.48–17.45) and malaria aOR = 0.91 (95% CI 0.51 to1.58). Effect of schistosomiasis coinfection on disease progression based on the odds of the diseases progressing to severe sequalae were: Severe pneumonia aOR = 8.41 (95% CI 3.09–22.93), p < 0.0001, complicated malaria aOR = 7.09 (95% CI 1.51–33.39), p = 0.02, severe dermatophytosis aOR = 20.3 (95% CI 4.78–83.20):p = 0.03, and fever of unknown origin aOR = 1.62 (95%CI 1.56–4.73), p = 0.02. Conclusion: This study revealed an association between schistosomiasis and the comorbidity conditions of URTI, dermatophytosis, malaria and FUO in PSAC living in a schistosomiasis endemic area. A possible detrimental effect where coinfection led to severe sequels of the comorbidity conditions was demonstrated. Appropriate clinical diagnostic methods are required to identify associated infectious diseases and initiate early treatment of schistosomiasis and co-infections in PSAC.

Background: Schistosomiasis is known to induce inflammatory immune responses. C-reactive protein (CRP), resistin and P-selectin are serological inflammatory markers that rise during the acute stages of infection. Here, we propose such inflammatory biomarkers have a potential for use in urogenital schistosomiasis diagnostic screening for exposure and infection in preschool-aged children. Methods: As part of a larger study on urogenital schistosomiasis, 299 preschool children aged 1–5 years were included in this cross-sectional study. Parasitological diagnosis was conducted using urine filtration for Schistosoma haemtobium infection, and Kato Katz for S. mansoni infection. Serum levels of P-selectin, resistin, CRP, and antibodies against S. haematobium cercarial antigen preparation (CAP) and soluble worm antigen preparation (SWAP) were measured by ELISA. Results: Of the 299 participants, 14% were egg positive for S. haematobium. Serology showed 46 and 9% of the participants to have been exposed to S. haematobium cercarial antigens and adult worm antigens, respectively. Levels of P-selectin were significantly higher in participants infected with S. haematobium (egg-positive) than in uninfected participants (p = 0.001). Levels of P-selectin were also higher in those exposed to cercarial antigen than in unexposed participants (p = 0.019). There was a positive correlation between P-selectin and infection intensity (r = 0.172; p = 0.002), as well as with IgM responses to CAP and SWAP (r = 0.183; p = 0.001); (r = 0.333; p < 0.0001) respectively. CRP significantly correlated with IgM responses to CAP (r = 0.133; p = 0.029) while resistin correlated with IgM responses to CAP and SWAP (r = 0.127; p = 0.016); (r = 0.197; p = 0.0004). CRP levels were higher in those exposed to cercarial and adult worm antigens than unexposed participants (p = 0.035); (p = 0.002) respectively, while resistin was higher in participants exposed to cercarial antigen than unexposed participants (p = 0.024). Conclusion: In this preschool population, P-selectin is significantly associated with urogenital schistosome infection and intensity; hence a potential biomarker for infection diagnosis and disease monitoring. The inflammatory biomarkers (P-selectin, Resistin and CRP) were significantly higher in participants exposed to cercarial antigens than unexposed individuals indicating an underlying inflammatory environment.

Background: Trichiasis is present when one or more eyelashes touches the eye. Uncorrected, it can cause blindness. Accurate estimates of numbers affected, and their geographical distribution, help guide resource allocation. Methods: We obtained district-level trichiasis prevalence estimates for 44 endemic and previously-endemic countries. We used (1) the most recent data for a district, if more than one estimate was available; (2) age- and sex-standardized corrections of historic estimates, where raw data were available; (3) historic estimates adjusted using a mean adjustment factor for districts where raw data were unavailable; and (4) expert assessment of available data for districts for which no prevalence estimates were available. Findings: Internally age- and sex-standardized data represented 1,355 districts and contributed 662 thousand cases (95% confidence interval [CI] 324 thousand-1.1 million) to the global total. age- and sex-standardized district-level prevalence estimates differed from raw estimates by a mean factor of 0.45 (range 0.03-2.28). Previously non-standardized estimates for 398 districts, adjusted by ×0.45, contributed a further 411 thousand cases (95% CI 283-557 thousand). Eight countries retained previous estimates, contributing 848 thousand cases (95% CI 225 thousand-1.7 million). New expert assessments in 14 countries contributed 862 thousand cases (95% CI 228 thousand-1.7 million). The global trichiasis burden in 2016 was 2.8 million cases (95% CI 1.1-5.2 million). Interpretation: The 2016 estimate is lower than previous estimates, probably due to more and better data; scale-up of trichiasis management services; and reductions in incidence due to lower active trachoma prevalence. Author Summary: As an individual with trichiasis blinks, the eyelashes abrade the cornea, which can lead to corneal opacity and blindness. Through high quality surgery, which involves correcting the position of the in-turned eyelid, it is possible to reduce the number of people with trichiasis. An accurate estimate of the number of persons with trichiasis and their geographical distribution are needed in order to effectively align resources for surgery and other necessary services. We obtained district-level trichiasis prevalence estimates for 44 endemic and previously-endemic countries. We used the most recently available data and expert assessments to estimate the global burden of trichiasis. We estimated that in 2016 the global burden was 2.8 million cases (95% CI 1.1-5.2 million). The 2016 estimate is lower than previous estimates, probably due to more and better data; scale-up of trichiasis management services; and reductions in incidence due to lower active trachoma prevalence.

Global Control Efforts of Schistosomiasis and Soil-Transmitted Helminthiasis | InTechOpen, Published on: 2017-02-15. Authors: Takafira Mduluza, Tawanda J. Chisango, Agness F. Nhidza, et

Individuals living in malaria-endemic regions may be exposed to more than one Plasmodium species; there is paucity of data on the distribution of the different species of Plasmodium in affected populations, in part due to the diagnostic method of microscopy, which cannot easily differentiate between the species. Sero-epidemiological data can overcome some of the shortcomings of microscopy. The specificity of IgG antibodies to recombinant merozoite surface protein 1 (MSP-119) derived from four human Plasmodium species (Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae, Plasmodium ovale) was investigated using competition enzyme-linked immunosorbent assay. Subsequently, these antigens were used to determine the exposure prevalence to the different Plasmodium species in serum samples of participants. One-hundred individuals, aged five-18 years, from each of the three Plasmodium meso-endemic Zimbabwean villages (Burma Valley, Mutoko, Chiredzi) were recruited in the study. The study demonstrated that the host serum reactivity to MSP-119 antigens was species-specific and that no cross-reactivity occurred. The overall prevalence of antibody response to MSP-119 antigens was 61 % in Burma Valley, 31 % in Mutoko and 32 % in Chiredzi. Single species IgG responses to MSP-119 were most frequent against P. falciparum, followed by P. malariae and P. ovale, with responses to P. vivax being the least prevalent. Interestingly, 78–87 and 50 % of sera with IgG responses to P. malariae and P. ovale MSP-119, respectively, also had IgG specific response for P. falciparum MSP-119 antigens, indicating that exposure to these species is a common occurrence in these populations. Single species IgG responses to the non-falciparum species were at a very low frequency, ranging between 0 and 13 % for P. malariae. There is evidence of a higher exposure to the non-falciparum parasite species than previously reported in Zimbabwe. The recombinant MSP-119 antigens could be used as additional diagnostic tools in antibody assays for the detection of exposure to the different Plasmodium species. The results also introduce an interesting concept of the co-infection of non-falciparum Plasmodium almost always with P. falciparum, which requires further validation and mechanistic studies.

Schistosomiasis and STH are among the list of neglected tropical diseases considered for control by the WHO. Although both diseases are endemic in Zimbabwe, no nationwide control interventions have been implemented. For this reason in 2009 the Zimbabwe Ministry of Health and Child Care included the two diseases in the 2009–2013 National Health Strategy highlighting the importance of understanding the distribution and burden of the diseases as a prerequisite for elimination interventions. It is against this background that a national survey was conducted. A countrywide cross-sectional survey was carried out in 280 primary schools in 68 districts between September 2010 and August 2011. Schistosoma haematobium was diagnosed using the urine filtration technique. Schistosoma mansoni and STH (hookworms, Trichuris trichiura, Ascaris lumbricoides) were diagnosed using both the Kato Katz and formol ether concentration techniques. Schistosomiasis was more prevalent country-wide (22.7%) than STH (5.5%). The prevalence of S. haematobium was 18.0% while that of S. mansoni was 7.2%. Hookworms were the most common STH with a prevalence of 3.2% followed by A. lumbricoides and T. trichiura with prevalence of 2.5% and 0.1%, respectively. The prevalence of heavy infection intensity as defined by WHO for any schistosome species was 5.8% (range 0%–18.3% in districts). Only light to moderate infection intensities were observed for STH species. The distribution of schistosomiasis and STH varied significantly between provinces, districts and schools (pS. haematobium and S. mansoni) and soil transmitted helminthiasis (STH) are endemic in Zimbabwe but there has not been any study conducted to systematically map out the disease for control. Due to the public health significance of schistosomiasis and STH in Zimbabwe, a nationwide cross-sectional survey was conducted to map schistosomiasis and STH in 2010 and 2011, among 13,195 primary school children in 280 primary schools from 68 rural and urban districts in Zimbabwe. Urine filtration technique was used to determine the prevalence and intensity of S. haematobium. Both the Kato Katz and formol ether concentration techniques were used to determine the intensity and prevalence of S. mansoni and STH (hookworm, A. lumbricoides and Trichuris trichiura). Overall, the prevalence of schistosomiasis was 22.7% (ranging from 0%–62% in districts) and that of STH was 5.5%, ranging from 0%–45% in districts. There was an overlap of schistosomiasis and STH in space (43 of the 68 districts). Based on the results of this study that confirm nationwide predominance in distribution of schistosomiasis and a lesser extent of STH, Preventive Chemotherapy strategies were determined and recommended for the elimination of these two specific NTD in Zimbabwe.

Background: Chemokines have been reported to play an important role in granulomatous inflammation duringSchistosoma mansoniinfection. However there is less information on their role inSchistosoma haematobiuminfection, or on the effect of concurrent HIV-1 infection, as a potential modifying influence.Methods: To determine levels of MIP-1α/CCL3 chemokine in plasma ofS. haematobiumand HIV-1 co-infected and uninfected individuals in a rural black Zimbabwean community.A cohort was established of HIV-1 and schistosomiasis infection and co-infection comprising 379 participants. Outcome measures consisted of HIV-1 and schistosomiasis status and levels of MIP-1α/CCL3 in plasma at baseline and three months post treatment. An association was established between MIP-1α/CCL3 plasma levels with HIV-1 andS. haematobiuminfections.Results: A total of 379 adults formed the established cohort comprising 76 (20%) men and 303 (80%) women. Mean age was 33.25, range 17 - 62 years. The median MIP-1α/CCL3 plasma concentration was significantly higher inS. haematobiuminfected compared with uninfected individuals (p = 0.029). In contrast, there was no difference in the median MIP-1α/CCL3 levels between HIV-1 positive and negative individuals (p = 0.631). MIP-1α/CCL3 concentration in plasma was significantly reduced at three months after treatment with praziquantel (p = 000).Conclusion: The results of our study show that the MIP-1α/CCL3 levels were positively associated withS. haematobiumegg counts at baseline but not with HIV-1 infection status. MIP-1α/CCL3 levels were significantly reduced at three months post treatment with praziquantel. We therefore conclude that MIP-1α/CCL3 is produced during infection withS haematobium.S. haematobiuminfection is associated with increased MIP-1α/CCL3 levels in an egg intensity-dependent manner and treatment ofS. haematobiumis associated with a reduction in MIP-1α/CCL3.