Efficacy of praziquantel drug against Schistosoma haematobium and performance of urine reagent strips among pre-and-school aged children during the high transmission season in North-Western Tanzania.

The World Health Organization calls for schistosomiasis endemic countries to regularly monitor the efficacy of Praziquantel (PZQ) drug, the only antischistosomal drug used for four decades in Tanzania. In response to that call, the current study investigated the efficacy of single dose of PZQ against Schistosoma haematobium during the high transmission season and further assessed, the sensitivity and specificity of urine reagent strips before and after treatment. The study recruited a total of 2,498 -children aged (4 -17 years old) who provided a single urine sample that was visually examined for macro-haematuria, then using urine dipstick and urine filtration technique for microhaematuria and the presence of S. haematobium eggs. The baseline prevalence of S. haematobium eggs positive based on urine filtration test was 29.2 % (95 %CI:27.5-31.0) and that of microhaematuria was 43.1 % (95 %CI:41.1-45.0). Of the infected participants, 40.9 % (95 %CI:37.4-44.6) had a heavy intensity of infection and the geometrical mean intensity (GMI) of infection was 33.7 eggs/10mls of urine. A single dose of PZQ reduced the prevalence of infection to 16.2 %, the GMI of infection to 18.8eggs/10mls of urine and that of microhaematuria to 27.9 %. Cure rate and egg reduction rates (ERR) were 83.8 % and 44.3 % respectively. At baseline, the sensitivity and specificity of the urine reagent strips were 59.7 % and 93.8 %, whereas at post-treatment they were 16.7 % and 93.6 %. When PZQ drug is administered during the high transmission season, its efficacy in term of ERR is poor. The urine reagent strips had low sensitivity but high specificity at pre-and-post PZQ treatment.

Corrigendum: KODAMA exploratory analysis in metabolic phenotyping.

[This corrects the article DOI: 10.3389/fmolb.2022.1070394.].

High Specificity but Low Sensitivity of Lab-on-a-Disk Technique in Detecting Soil-Transmitted Helminth Eggs among Pre- and School-Aged Children in North-Western Tanzania.

An estimated 1.5 billion people are infected with soil-transmitted helminths (hookworms, Ascaris lumbricoides and Trichuris trichiura). These infections are targeted for elimination by the World Health Organization (WHO) by 2030, with the main interventions being mass drug administration using albendazole or mebendazole. Tanzania is one of the endemic countries; it has been implementing MDA to school-aged children for more than a decade and the infection prevalence and intensity of infection have declined. Thus, at this point, the monitoring and evaluation of infection prevalence and intensity of infections, and assessing drug efficacy is crucial and requires accurate diagnostic tests. The currently used standard diagnostic test, the Kato-Katz (KK) technique, has several limitations and the WHO is calling for the development and evaluation of new diagnostic tests. The Lab-on-a-disk (LOD) was developed and tested in the endemic areas of north-western Tanzania to evaluate its sensitivity and specificity using KK and the formol-ether concentration technique. The results showed that when using a duplicate KK slide, the LOD had a sensitivity and specificity of 37.2% (95% CI: 30.7-43.9) and 67.3% (95% CI: 63.1-71.3%). Using four KK slides as a standard technique, the overall sensitivity and specificity were 37.7% (95% CI: 33.1-42.6) and 70.7% (95% CI: 65.5-75.6). The LOD attained high specificity but low sensitivity especially in detecting eggs of Trichuris trichiura. The LOD technique has potential as a promising diagnostic test, but its sensitivity still requires improvement.

Precision and geographical prevalence mapping of schistosomiasis and soil-transmitted helminthiasis among school-aged children in selected districts of north-western Tanzania.

BACKGROUND: The identification and mapping of at-risk populations at a lower administrative level than the district are prerequisites for the planning, resource allocation and design of impactful control intervention measures. Thus, the objective of the current study was to conduct sub-district precision mapping of soil-transmitted helminthiasis (STH) and schistosomiasis in 29 districts of north-western Tanzania using the current recommended World Health Organization criteria. METHODS: A cross-sectional survey was conducted in 145 schools between March and May 2021. A urine filtration technique was used for the quantification of Schistosoma haematobium eggs, whereas quantification of Schistosoma mansoni and STH eggs was done using the Kato-Katz technique. Microhaematuria was examined using a urine dipstick. RESULTS: The overall prevalences of any STH and schistosome infections were 9.3% [95% confidence interval (95%CI) 8.6-9.9] and 14.6% (95%CI 13.9-15.4), respectively. The overall prevalence of S. mansoni was 8.7% (95%CI 8.1-9.3), and 36.4%, 41.6%, and 21.9% of the children had low, moderate, and heavy infections, respectively. The overall prevalence of S. haematobium was 6.1% (95%CI 5.5-6.5), and 71.7% and 28.3% of the infected children had light and heavy intensity infections, respectively. The prevalence of microhaematuria was 7.3% (95%CI 6.7-7.8), with males having the highest prevalence (8.4%, P < 0.001). The prevalences of Trichuris trichiura, Ascaris lumbricoides and hookworm were, respectively, 1.3% (95%CI 0.1-1.5), 2.9% (95%CI 2.5-3.3) and 6.2% (95%CI 5.7-6.7). Most of the children infected with STH had light to moderate intensities of infection. The overall prevalence of co-infection with STH and schistosomiasis was 19.1%. The prevalence of schistosomiasis (P < 00.1) and STH (P < 0.001) varied significantly between schools and sub-districts. Schistosoma mansoni and S. haematobium were observed in 60 and 71 schools, respectively, whereas any STH was observed in 49 schools. In schools where schistosomiasis was observed, prevalence was < 10% in 90.8% of them, and ranged from ≥ 10% to < 50% in the other 9.2%. In schools where any STH was observed, the prevalence was < 10% in 87.7% of them. CONCLUSIONS: The data reported here show that schistosomiasis and STH are widely distributed around Lake Victoria. In most of the schools where schistosomiasis and STH occurred the transmission thresholds were low. These data are important and need to be taken into consideration when decisions are made on the implementation of the next round of mass chemotherapies for schistosomiasis and STH in Tanzania.

Urogenital schistosomiasis among pre-school and school aged children in four districts of north western Tanzania after 15 years of mass drug administration: Geographical prevalence, risk factors and performance of haematuria reagent strips.

BACKGROUND: Urogenital schistosomiasis remains as a public health problem in Tanzania and for the past 15 years, mass drug administration (MDA) targeting primary school children has remained as the mainstay for its control. However, after multiple rounds of MDA in highly risk groups, there are no data on the current status of Schistosoma haematobium in known endemic areas. Furthermore, the performance of commonly used diagnostic test, the urine reagent strips is not known after the decline in prevalence and intensities of infection following repeated rounds of treatment. Thus, after 15 of national MDA, there is a need to review the strategy and infection diagnostic tools available to inform the next stage of schistosomiasis control in the country. METHODS/FINDINGS: A analytical cross-sectional study was conducted between October and November, 2019 among pre-school (3-5years old) and school aged children (6-17 years old) living in four (4) districts with low (<10%) and moderate (10%-<50%) endemicity for schistosomiasis as per WHO classification at the start of the national control programme in 2005/06, with mean prevalence of 20.7%. A total of 20,389 children from 88 randomly selected primary schools participated in the study. A questionnaire was used to record demographic information. A single urine sample was obtained from each participant and visually examined for macrohaematuria, tested with a dipstick for micro-haematuria, to determine blood in urine; a marker of schistosome related morbidity and a proxy of infection. Infection intensity was determined by parasitological examination of the urine sample for S. haematobium eggs. Overall, mean infection prevalence was 7.4% (95%CI: 7.0-7.7, 1514/20,389) and geometric mean infection intensity was 15.8eggs/10mls. Both infection prevalence (5.9% versus 9%, P<0.001) and intensity (t = -6.9256, P<0.001) were significantly higher in males compared to females respectively. Light and heavy infections were detected in 82.3% and 17.7% of the positive children respectively. The prevalence of macrohaematuria was 0.3% and that of microhaematuria was 9.3% (95%CI:8.9-9.7). The sensitivity and specificity of the urine reagent strip were 78% (95%CI: 76.1-79.9) and 99.8% (95%CI: 99.7-99.9). Having light (P<0.001) and heavy infection intensities (P<0.001) and living in the study districts increased the odd of having microhaematuria. Predictors of S. haematobium infection were being male (P<0.003), microhaematuria (P<0.001), and living in the three study districts (P<0.001) compared to living at Nzega district. CONCLUSION: The findings provide an updated geographical prevalence which gives an insight on the planning and implementation of MDA. Comparing with the earlier mapping survey at the start of the national wide mass drug administration, the prevalence of S. haematobium infection have significantly declined. This partly could be attributed to repeated rounds of mass drug administration. The urine reagent strips remain as a useful adjunct diagnostic test for rapid monitoring of urogenital schistosomiasis in areas with low and high prevalence. Based on prevalence levels and with some schools having no detectable infections, review of the current blanket mass drug administration is recommended.

KODAMA exploratory analysis in metabolic phenotyping.

KODAMA is a valuable tool in metabolomics research to perform exploratory analysis. The advanced analytical technologies commonly used for metabolic phenotyping, mass spectrometry, and nuclear magnetic resonance spectroscopy push out a bunch of high-dimensional data. These complex datasets necessitate tailored statistical analysis able to highlight potentially interesting patterns from a noisy background. Hence, the visualization of metabolomics data for exploratory analysis revolves around dimensionality reduction. KODAMA excels at revealing local structures in high-dimensional data, such as metabolomics data. KODAMA has a high capacity to detect different underlying relationships in experimental datasets and correlate extracted features with accompanying metadata. Here, we describe the main application of KODAMA exploratory analysis in metabolomics research.

Knowledge, perception and practices about malaria, climate change, livelihoods and food security among rural communities of central Tanzania.

BACKGROUND: Understanding the interactions between malaria and agriculture in Tanzania is of particular significance when considering that they are the major sources of illness and livelihoods. The objective of this study was to determine knowledge, perceptions and practices as regards to malaria, climate change, livelihoods and food insecurity in a rural farming community in central Tanzania. METHODS: Using a cross-sectional design, heads of households were interviewed on their knowledge and perceptions on malaria transmission, symptoms and prevention and knowledge and practices as regards to climate change and food security. RESULTS: A total of 399 individuals (mean age = 39.8 ± 15.5 years) were interviewed. Most (62.41%) of them had attained primary school education and majority (91.23%) were involved in crop farming activities. Nearly all (94.7%) knew that malaria is acquired through a mosquito bite. Three quarters (73%) reported that most people get sick from malaria during the rainy season. About 50% of the respondents felt that malaria had decreased during the last 10 years. The household coverage of insecticide treated mosquito nets (ITN) was high (95.5%). Ninety-six percent reported to have slept under a mosquito net the previous night. Only one in four understood the official Kiswahili term (Mabadiliko ya Tabia Nchi) for climate change. However, there was a general understanding that the rain patterns have changed in the past 10 years. Sixty-two percent believed that the temperature has increased during the same period. Three quarters of the respondents reported that they had no sufficient production from their own farms to guarantee food security in their household for the year. Three quarters (73.0%) reported to having food shortages in the past five years. About half said they most often experienced severe food shortage during the rainy season. CONCLUSION: Farming communities in Kilosa District have little knowledge on climate change and its impact on malaria burden. Food insecurity is common and community-based strategies to mitigate this need to be established. The findings call for an integrated control of malaria and food insecurity interventions.

Accessibility, availability and utilisation of malaria interventions among women of reproductive age in Kilosa district in central Tanzania.

BACKGROUND: Universal access to and utilization of malaria prevention measures is defined as every person at malaria risk sleeping under a quality insecticide-treated mosquito net (ITN) and every pregnant woman at risk receiving at least two doses of sulfadoxine-pyrimethamine (SP). This study aimed to determine factors affecting accessibility, availability and utilisation of malaria interventions among women of reproductive age in Kilosa district in central Tanzania. METHODS: Women of reproductive age with children <5 years old or those who had been pregnant during the past 5 years were included in the study. A structured questionnaire was used to seek information on malaria knowledge, accessibility and utilization of malaria interventions during pregnancy. RESULTS: A total of 297 women (mean age=29±6.8 years) were involved. Seventy percent of the women had attained primary school education. About a quarter of women had two children of <5 years while over 58% had ≥3 children. Most (71.4%) women had medium general knowledge on malaria while only eight percent of them had good knowledge on malaria in pregnancy. A significant proportion of women were not aware of the reasons for taking SP during pregnancy (35%), timing for SP (18%), and the effect of malaria on pregnancy (45.8%). Timing for first dose of SP for intermittent preventive treatment in pregnancy (IPTp) was 1-3 months (28.4%) and 4-6 months (36.8%). Some 78.1% were provided with SP under supervision of the health provider. Knowledge on malaria in pregnancy had a significant association with levels of education (p=0.024). Ninety-eight percent had an ITN, mostly (87.1%) received free from the government. All women attended the ANC during their last pregnancy. The coverage of IPT1 was 53.5% and IPTp2 was 41.1%. The proportion of women making more ANC visits decreased with increasing parity. CONCLUSION: This study showed that the knowledge of the pregnant women on malaria in pregnancy and IPTp was average and is likely to have an impact on the low IPTp coverage. Campaigns that provide educational massages on the risk of malaria during pregnancy and the usefulness of IPTp need to be emphasised.

Home treatments with antipyretics and antimalarials given to underfives with fever in Mwanza, north-western Tanzania.

Early diagnosis and prompt treatment is the recommended management for febrile illness among underfives. However, improper home management may be the cause of delay in seeking professional health care. This cross-sectional study was conducted at the outpatient department of Buzuruga Health Centre in Mwanza, Tanzania and involved 372 children < 5 years of age. Socio-demographic data of caregivers and children, type and source of treatment, and duration of fever were recorded. A total of 283 (76.1%) febrile underfives had received different types of treatment at home, before presenting at the hospital. The majority received antipyretics (204; 72.1%), and only a few (31; 10.9%) received antimalarials. The major sources of drugs were local drug stores (270; 94.7%). Duration of fever > 1 day (OR = 2.69; 95% CI: 1.95-3.70; P < 0.001), low grade fever (OR = 4.37, 95% CI: 2.60-7.35; P < 0.001) and fever accompanied with other major complaints (OR = 1.14, 95% CI: 1.05 - 1.23; P = 0.002) were significantly associated with prompt home medication before presenting to the health centre. In logistic regression analysis, duration of fever, low-grade fever and the presence of other symptoms remained significant predictors to receive antimalarial and or antipyretic drugs. In conclusion, home treatments with antipyretics and antimalarials in preschool children are common in Mwanza. Management of fevers may be improved by educating caregivers on community standard case definition of malaria while emphasizing the importance of early seeking of health facility services.

Intestinal schistosomiasis associated with intussusception: a case report.

We report a case of intestinal schistosomiasis associated with iliocaecal intussusception resulting from obstructions of the terminal part of the ileum by schistosome egg-induced fibrosis. A 7-year-old boy presented with the history of abdominal pain and difficulties in passing stool for two months. Ultrasound examination revealed doughnut signs characterized with multiple concentric rings at the lateral abdomen, and the bowel loop appeared distended. Exploratory laparatomy confirmed intussusception of the terminal part of the ileum into the caecum, extending to the ascending colon. Hemicolectomy and end-to-end iliocolostomy was performed. Histological examination of the resected bowel revealed Schistosoma mansoni eggs within the mucosa, submucosa of the ileum, caecum and ascending colon, granulomatous inflammation with foreign body giant cells accompanied by fibrosis and eosinophilic infiltrate into the mucosa. Postoperatively, the patient recovered well. There may have been a synergistic effect of schistosomiasis with other underlying conditions, leading to intussusception. In conclusion, it is important to consider S. mansoni infection as a differential diagnosis for intestinal obstruction in endemic areas.

Severe tungiasis in Western Tanzania: case series.

Tungiasis is caused by infestation with the sand flea (Tunga penetrans). This ectoparasitosis is endemic in economically depressed communities in South American and African countries. However, data on the epidemiology of tungiasis in Tanzania are very limited and the disease does not receive much attention from health care professionals. During a community cross sectional survey in northwest Tanzania, we identified five individuals extremely infested with high number of parasites. A total of 435 lesions were recorded with patients presenting with >75 lesions and showed signs of intense acute and chronic inflammation. Superinfection of the lesions characterized by pustule formation, suppuration and ulceration were common. Loss of nails and walking difficulty was also observed. In Tanzanian communities living under extreme poverty characterized by poor housing condition and inadequate health services, tungiasis may cause severe morbidities. Further studies on risk factors and disease-related behavior of affected populations are needed to design adequate control measures.

Knowledge; Attitudes; and Practices about Malaria and its Control in Rural Northwest Tanzania

Background. We assessed community knowledge; attitudes; and practices on malaria as well as acceptability to indoor residual spraying. Material and Methods. A cross-sectional survey was done in a community in Geita district (northwest Tanzania). Household heads (n=366) were interviewed Results. Knowledge on malaria transmission; prevention; and treatment was reasonable; 56of respondents associated the disease with mosquito bites; with a significant difference between education level and knowledge on transmission (P.001). Knowledge of mosquito breeding areas was also associated with education (illiterate: 22; literate: 59(P.001). Bed nets were used by 236 (64.5); and usage was significantly associated with education level (P.01). The level of bed net ownership was 77.3. Most respondents (86.3) agreed with indoor residual spraying of insecticides. Health facilities were the first option for malaria treatment by 47.3. Artemether-lumefantrine was the most common antimalarial therapy used. Conclusions. Despite reasonable knowledge on malaria and its preventive measures; there is a need to improve availability of information through proper community channels. Special attention should be given to illiterate community members. High acceptance of indoor residual spraying and high level of bed net ownership should be taken as an advantage to improve malaria control

Schistosomal peritonitis secondary to perforated appendicitis

In Tanzania, Schistosoma mansoni is endemic and causes intestinal schistosomiasis which affects various internal organs. However, worldwide there have been very few reports of cases of peritonitis due to schistosomal appendicitis. Here we report a rare case of schistosomal appendicitis with peritonitis in a 33 year-old male patient who recovered quickly after surgery.

Case Series of Adenocarcinoma of the Prostate Associated with Schistosoma haematobium Infection in Tanzania.

In endemic areas, schistosomiasis has been associated with the pathogenesis of bladder, prostate, colorectal and renal carcinoma. However, the relationship between prostate cancer and schistosomiasis infection remains controversial. Here we present a series of three cases from Tanzania of prostatic adenocarcinoma associated with urinary schistosomiasis.

Co-infections with Plasmodium falciparum, Schistosoma mansoni and intestinal helminths among schoolchildren in endemic areas of northwestern Tanzania.

BACKGROUND: Malaria, schistosomiasis and intestinal helminth infections are causes of high morbidity in most tropical parts of the world. Even though these infections often co-exist, most studies focus on individual diseases. In the present study, we investigated the prevalence of Plasmodium falciparum-malaria, intestinal schistosomiasis, soil-transmitted helminth infections, and the respective co-infections, among schoolchildren in northwest Tanzania. METHODS: A cross sectional study was conducted among schoolchildren living in villages located close to the shores of Lake Victoria. The Kato Katz technique was employed to screen faecal samples for S. mansoni and soil-transmitted helminth eggs. Giemsa stained thick and thin blood smears were analysed for the presence of malaria parasites. RESULTS: Of the 400 children included in the study, 218 (54.5%) were infected with a single parasite species, 116 (29%) with two or more species, and 66 (16.5%) had no infection. The prevalences of P. falciparum and S. mansoni were 13.5% (95% CI, 10.2-16.8), and 64.3% (95% CI, 59.6-68.9) respectively. Prevalence of hookworm infection was 38% (95% CI, 33.2-42.8). A. lumbricoides and T. trichiura were not detected. Of the children 26.5% (95% CI, 21.9-30.6) that harbored two parasite species, combination of S. mansoni and hookworm co-infections was the most common (69%). Prevalence of S. mansoni - P. falciparum co-infections was 22.6% (95%CI, 15.3-31.3) and that of hookworm - P. falciparum co-infections 5.7% (95%CI, 2.6-12.8). Prevalence of co-infection of P. falciparum, S. mansoni and hookworm was 2.8% (95%CI, 1.15-4.4). CONCLUSION: Multiple parasitic infections are common among schoolchildren in rural northwest Tanzania. These findings can be used for the design and implementation of sound intervention strategies to mitigate morbidity and co-morbidity.

Tungiasis infestation in Tanzania.

Tungiasis is caused by the jigger flea Tunga penetrans. We describe a case of severe infestation from Kigoma region, Western Tanzania. A 19-year-old male with epilepsy and mental disability presented with ulcerated and inflamed toes. Clinical examination revealed the presence of approximately 810 embedded jigger fleas on the feet, and another 60 lesions on the hands. The patient presented with fissures on the feet, hands and soles. He had difficulty walking and erythematous, oedematous, ulcerated and inflamed skin around the feet. Living conditions were precarious. The patient was assisted to extract the embedded fleas and his feet were washed with disinfectants. Oral antibiotics were given. The case shows that the disease may reach high parasite loads in Tanzanian individuals, with consequently severe pathology. There have been single reports of returning tourists from Tanzania with tungiasis, but the epidemiological situation and the geographic occurrence of the disease in this country are not known. Systematic studies are needed to increase knowledge on the epidemiological situation of tungasis in Tanzania and to identify endemic areas.

Schistosomal peritonitis secondary to perforated appendicitis.

In Tanzania, Schistosoma mansoni is endemic and causes intestinal schistosomiasis which affects various internal organs. However, worldwide there have been very few reports of cases of peritonitis due to schistosomal appendicitis. Here we report a rare case of schistosomal appendicitis with peritonitis in a 33 year-old male patient who recovered quickly after surgery.

Knowledge, Attitudes, and Practices about Malaria and Its Control in Rural Northwest Tanzania.

Background. We assessed community knowledge, attitudes, and practices on malaria as well as acceptability to indoor residual spraying. Material and Methods. A cross-sectional survey was done in a community in Geita district (northwest Tanzania). Household heads (n = 366) were interviewed Results. Knowledge on malaria transmission, prevention, and treatment was reasonable; 56% of respondents associated the disease with mosquito bites, with a significant difference between education level and knowledge on transmission (P < .001). Knowledge of mosquito breeding areas was also associated with education (illiterate: 22%; literate: 59% (P < .001). Bed nets were used by 236 (64.5%), and usage was significantly associated with education level (P < .01). The level of bed net ownership was 77.3%. Most respondents (86.3%) agreed with indoor residual spraying of insecticides. Health facilities were the first option for malaria treatment by 47.3%. Artemether-lumefantrine was the most common antimalarial therapy used. Conclusions. Despite reasonable knowledge on malaria and its preventive measures, there is a need to improve availability of information through proper community channels. Special attention should be given to illiterate community members. High acceptance of indoor residual spraying and high level of bed net ownership should be taken as an advantage to improve malaria control.

Association of intestinal helminths and P. falciparum infections in co-infected school children in northwest Tanzania.

Plasmodium falciparum malaria and intestinal helminth infections are among the most common infections in the tropics and they share the same spatial distribution. The objective of this study was to explore the association between infections with intestinal helminths and P. falciparum infection as single helminth infections or co-infections among school children. A cross-sectional study was conducted among 400 school children in Nyamtongo, Sengerema District in Tanzania. The study involved examination of single stool and finger prick blood samples for intestinal helminths and malaria parasites. A Kato-Katz technique was employed to screen for intestinal helminths and Giemsa stained thin and thick blood smears were used to screen for malaria parasites. The results of logistic regression model adjusted for age and sex indicated no association between P. falciparum and S. mansoni (OR= 0.749, 95%CI 0.418-1.344), P. falciparum and hookworm (OR= 0.885, 95%CI 0.489-1.605) and P. falciparum and co-infection of S. mansoni and hookworm (OR=0.859, 95%CI 0.422-1.745). Using multinomial regression model adjusted for age and sex, no association was observed between P. falciparum with Schistosoma mansoni [Ratio of Relative Risk (RRR) = 0.651, 95% Confidence Interval (CI) 0.331-1.363] and hookworm (RRR=0712, CI 0.280-1.765). Similarly, no association was observed between co-infections of S. mansoni + hookworm (RRR=0.635, CI 0.268-1.504) with P. falciparum infection. Coinfections of S. mansoni, hookworm and P. falciparum among school children is common in the Nyamatongo ward, Sengerema District. We recommend prospective longitudinal studies to elucidate the interactions of malaria and helminths and its health impact in risk groups.