Spatial distribution of urinary schistosomiasis in Cross River State, Nigeria using geographical information system and school based questionnaire

Detecting Schistosoma haematobium infection by microscopy and polymerase chain reaction (PCR) in school children in three senatorial districts of Cross River State, Nigeria

As a result of the poor sensitivity and specificity of the standard parasitological diagnostic methods currently being used, this study was conducted to compare the standard parasitological diagnostic methods and Polymerase Chain Reaction (PCR) in determining the prevalence of urinary schistosomiasis in Cross River State (CRS). The study was conducted between April 2015 and March 2016. Seven hundred and seventy seven (777) urine samples were randomly collected from selected school-age children. The urine samples were subjected to standard parasitological and molecular examinations. Chi-square test was used to test the differences between the data on subgroups and the results from specimen examinations. An overall prevalence of 1.7% was recorded using microscopy and 34.7% recorded using PCR. The highest prevalence of infection by microscopy occurred in the Southern Senatorial District (2.3%), while the Northern Senatorial District recorded the highest prevalence of infection by PCR (53.2%) (p < 0.05). Males were more infected (2.4%) than females (0.6%) using microscopy. With PCR, males were also more infected (35.7%) compared to females (33.3%) (p < 0.05). The highest prevalence of infection using microscopy and PCR both occurred in school-age children aged 5-8 years (3.6% and 47.8% respectively), while the lowest prevalence for both methods occurred in participants aged 17 - 20 years (0% for both methods) (p < 0.05). This study has shown PCR to be effective in detecting schistosomiasis infection and also re-affirms the endemicity of urinary schistosomiasis in the three Senatorial Districts of CRS.

Urogenital Schistosomiasis among Primary School Children in Rural Communities in Obudu, Southern Nigeria

BACKGROUND

Schistosomiasis is a Neglected Tropical Disease (NTD) that constitutes a public health problem in Sub-Saharan Africa (SSA), including Nigeria. There is need for updated information on the extent of the disease burden at community level to facilitate effective prioritization and monitoring of the disease.

METHODS

A cross-sectional study was conducted among school-aged children in Obudu Local Government Area (LGA), one of the 18 LGAs in Cross River State, Southern Nigeria. Seven schools from seven communities were randomly selected for this study. A total of 1,113 urine samples obtained from school-aged children were screened for Schistosoma haematobium (S. haematobium) eggs using standard parasitological method of diagnosis. Proteinuria and hematuria were evaluated using reagent test strips.

RESULTS

In this study, 153 (13.7%) children were infected with S. haematobium. More males (86 or 14.7%) were infected than females (67 or 12.7%); the differences were not statistically significant. The overall geometric mean intensity of infection was 13.3 eggs/10ml of urine. Females (13.69 eggs/10ml of urine) had the highest intensity of infection than males (12.91eggs/10ml of urine). Prevalence of hematuria was 152 (13.7%) (95% C.I. = 10.649 - 18.751%) while the prevalence of proteinuria was 172 (15.5%) (95% C.I. = 5.162 - 38.712%). Prevalence of infection significantly (p<0.001) varied among the schools from 7.8% to 28.9%. Children aged 5-9 years old had the highest prevalence of infection 46 (17.1%). The prevalence of urogenital schistosomiasis was 28.9%, 20.5% and 13.2%, respectively, among Betukwel, Ibong, and Ohong communities.

CONCLUSION AND GLOBAL HEALTH IMPLICATIONS

Urinary schistosomiasis is still endemic in Obudu, Southern Nigeria but with decreased prevalence. Public health mitigation efforts such as mass chemotherapy, provision of safe water supply and sanitation facilities are recommended. Furthermore, health education should be encouraged within schools and communities.

Epidemiological dynamics and associated risk factors of S. haematobium in humans and its snail vectors in Nigeria: a meta-analysis (1983-2018)

Schistosoma haematobium, a major pathogen of urogenital schistosomiasis, has been reported to be affecting an estimated 30 million people in Nigeria. Current national estimates of S. haematobium and its cercariae, in humans and snail vectors respectively, are lacking in Nigeria, hence systematic meta-analyses were conducted to understand the disease dynamics in the endemic country over a period of 35 years based on publications from five databases (AJOL, Ovid MEDLINE, Google Scholar, PubMed and Web of Science). The preferred reporting items for systematic reviews and meta-analyses (PRIMSA) checklist were used as the standard guide for the analyses. The prevalence of S. haematobium in human hosts in Nigeria using quality effects model was 32.1% (27.3-37.2), while schistosome cercariae were observed at 3.5% (0.0-11.9), 18.2% (4.7-36.8) and 18.7% (0.0-46.1) and for B. forskalii, Bulinus globosus and B. truncatus, respectively. The high report of schistosome cercariae indicates the continuous transmission of S. haematobium in humans especially with individuals who have frequent contact with freshwater. Heterogeneity of subgroup analyses (regions, zones, sex, age groups, diagnostic techniques) and risk factors (pathological signs, occupation, water sources, anthropogenic activities, treatment) were determined. The result showed prevalence of an endemic moderate class infection that has been linked to several risk factors. Therefore, there is need for increased awareness on the prevalence, transmission routes and treatment strategies to mitigate the disease in this endemic area.

Rapid Risk Assessment Report for Schistosomiasis Epidemic in Jianli County Caused by the Sunk "Oriental Star" Cruise Ship

BACKGROUND

At 9:28 pm on June 1, 2015, the cruise ship "Oriental Star" sank into Yangtze River in Jianli County, with 422 people killed. When the accident occurred, the Chinese government took immediate action and dispatched more than 9000 rescuers. The risk for outbreak of schistosomiasis was increased because of the shipwreck. Obviously it is critical to carry out risk assessment as soon as possible.

METHODS

By means of the Delphi method, the situation was analyzed so that the government could fathom the severity of the accident. Then, through matrix and sigma-plotting (3-dimensional graphics) methods, related authorities performed risk assessment after site investigation.

RESULTS

The latest news reported that more than 9000 people were involved in the rescue. The affected river was analyzed and mapped using SigmaPlot software, according to which the possibility, harmfulness, and controllability of the accident were determined to be medium (6), medium (6), and poor (7), respectively.

CONCLUSION

The site of the accident where the cruise ship sank and rescue operations were carried out is a schistosomiasis epidemic area with high mortality and morbidity. The chance of an outbreak of the schistosomiasis epidemic in Jianli County is quite high. To protect people in this county from the epidemic, relevant logistic services should be arranged and all remains should be cleared up carefully. (Disaster Med Public Health Preparedness. 2018;12:147-153).