Pathological Abnormalities Observed on Ultrasonography among Fishermen Associated with Male Genital Schistosomiasis (MGS) along the South Lake Malawi Shoreline in Mangochi District, Malawi

Schistosome eggs cause granulomata and pathological abnormalities, detectable with non-invasive radiological techniques such as ultrasonography which could be useful in male genital schistosomiasis (MGS). As part of our novel MGS study among fishermen along Lake Malawi, we describe pathologies observed on ultrasonography and praziquantel (PZQ) treatment over time. Fishermen aged 18+ years were recruited, submitted urine and semen for parasitological and molecular testing, and thereafter, transabdominal pelvic and scrotal ultrasonography, assessing pathologies in the prostate, seminal vesicles, epididymis and testes. Standard PZQ treatment and follow-up invitation at 1-, 3-, 6- and 12-months’ time-points were offered. A total of 130 recruited fishermen underwent ultrasonography at baseline (median age: 32.0 years); 27 (20.9%, n = 129) had S. haematobium eggs in urine (median: 1.0 egg/10 mL), 10 (12.3%, n = 81) in semen (defined as MGS, median: 2.9 eggs/mL ejaculate) and 16 (28.1%, n = 57) had a positive seminal Schistosoma real-time PCR. At baseline, 9 fishermen (6.9%, n = 130) had abnormalities, with 2 positive MGS having prostatic and testicular nodules. Fewer abnormalities were observed on follow-up. In conclusion, pathologies detected in male genitalia by ultrasonography can describe MGS morbidity in those with positive parasitological and molecular findings. Ultrasonography advances and accessibility in endemic areas can support monitoring of pathologies’ resolution after treatment

An outbreak of intestinal schistosomiasis, alongside increasing urogenital schistosomiasis prevalence, in primary school children on the shoreline of Lake Malawi, Mangochi District, Malawi

Background: Intestinal schistosomiasis was not considered endemic in Lake Malawi until 14 November 2017 when populations of Biomphalaria pfeifferi were first reported; in May 2018, emergence of intestinal schistosomiasis was confirmed. This emergence was in spite of ongoing control of urogenital schistosomiasis by preventive chemotherapy. Our current study sought to ascertain whether intestinal schistosomiasis is transitioning from emergence to outbreak, to judge if stepped-up control interventions are needed. Methods: During late-May 2019, three cross-sectional surveys of primary school children for schistosomiasis were conducted using a combination of rapid diagnostic tests, parasitological examinations and applied morbidity-markers; 1) schistosomiasis dynamics were assessed at Research Article IDOP Samama (n = 80) and Mchoka (n = 80) schools, where Schistosoma mansoni was first reported, 2) occurrence of S. mansoni was investigated at two non-sampled schools, Mangochi Orphan Education and Training (MOET) (n = 60) and Koche (n = 60) schools, where B. pfeifferi was nearby, and 3) rapid mapping of schistosomiasis, and B. pfeifferi, conducted across a further 8 shoreline schools (n = 240). After data collection, univariate analyses and Chi-square testing were performed, followed by binary logistic regression using generalized linear models, to investigate epidemiological associations. Results: In total, 520 children from 12 lakeshore primary schools were examined, mean prevalence of S. mansoni by ‘positive’ urine circulating cathodic antigen (CCA)-dipsticks was 31.5% (95% Confidence Interval (CI): 27.5–35.5). Upon comparisons of infection prevalence in May 2018, significant increases at Samama (Relative Risk (RR) = 1.7, 95% CI: 33 1.4–2.2) and Mchoka (RR = 2.7, 95% CI: 1.7–4.3) schools were observed. Intestinal schistosomiasis was confirmed at MOET (18.3%) and Koche (35.0%) schools, and in all rapid mapping schools, ranging from 10.0% to 56.7%. Several populations of B. pfeifferi were confirmed, with two new eastern shoreline locations noted. Mean prevalence of urogenital schistosomiasis was 24.0% (95% CI: 20.3–27.7). Conclusions: We notify that intestinal schistosomiasis, once considered non-endemic in Lake Malawi, is now transitioning from emergence to outbreak. Once control interventions can resume after coronavirus disease 2019 (COVID-19) suspensions, we recommend stepped-up preventive chemotherapy, with increased community-access to treatments, alongside renewed efforts in appropriate environmental control

Molecular Epidemiology and Assemblage Typing of Giardia duodenalis in School-Age Children Situated along the Southern Shoreline of Lake Malawi, Malawi

Almost all human giardiasis infections are caused by Giardia duodenalis assemblages A and B. Differentiation between human infections with these assemblages, as well as between single-assemblage (A or B) and mixed-assemblage (A and B) infections, is therefore needed to better understand the pathological impact of infection with either, or both, assemblages. We assessed the prevalence of G. duodenalis assemblages A and B using 305 fecal samples provided by school-age children situated along the southern shoreline of Lake Malawi. Concurrently, intestinal pathology data were also collected to test for association(s) between assemblage infection status and intestinal health. Prevalence of G. duodenalis infection was 39.3% by real-time polymerase chain reaction. Of all identified infections, 32% were single G. duodenalis assemblage A and 32% were single G. duodenalis assemblage B, whereas 33% were mixed-assemblage infections. Fifteen unique G. duodenalis assemblage A and 13 unique G. duodenalis assemblage B β-giardin haplotypes were identified. There was a positive association between single infection with G. duodenalis assemblage B and both self-reporting of abdominal pain (odds ratio [OR]: 3.05, P = 0.004) and self-reporting of diarrhea (OR: 3.1, P = 0.003). No association between single infection with assemblage A and any form of intestinal pathology was found. Additionally, there was a positive association between mixed-assemblage infections and self-reporting of abdominal pain (OR: 3.1, P = 0.002). Our study highlights the importance G. duodenalis assemblage typing and reaffirms the need for improved access to water, sanitation and hygiene infrastructure in rural areas of low- and middle-income countries

Challenges in the diagnosis and control of female genital schistosomiasis in sub-Saharan Africa: an exemplar case report associated with mixed and putative hybrid schistosome infection in Nsanje District, Southern Malawi

Female genital schistosomiasis (FGS) remains an often overlooked chronic complication of urogenital schistosomiasis in adolescent girls and women. Moreover, the role of zoonotic or hybrid schistosome infection(s) is poorly appreciated, but is increasingly becoming an emerging public health concern in sub-Saharan Africa. In Southern Malawi, during the “Hybridization in UroGenital Schistosomiasis (HUGS)” study visit, we describe the case of a 33-year-old woman with suspected FGS who partook in a detailed external assessment with internal cervical examination using a portable colposcope. She provided several biological samples for analysis with traditional and molecular parasitological methods—urine, cervicovaginal lavage (CVL), cervical swabs, and external mass and cervical biopsies—alongside provision of detailed demographic information after a thorough medical history questionnaire and an in-depth interview. These samples were screened for the presence of Schistosoma ova on microscopy and DNA genotyping using a novel real-time PCR assay in parallel to pre-published probe-based PCR assays capable of identifying and discriminating up to six named Schistosoma species. A further molecular screen of sexually transmitted infections (STIs) including Trichomonas vaginalis, Chlamydia spp., and human papilloma virus (HPV) was conducted on her genital swab and CVL. Overt FGS was diagnosed on clinical colposcopy alongside inspection of the cervical biopsy by microscopy, real-time PCR, and histopathology. The urine filtration, microscopy and real-time PCR of the CVL and swab were negative. This evidences the typical diagnostic challenge, and cases such as this will pose an unmet need in satisfactory patient management. In addition to Schistosoma haematobium, the presence of the zoonotic species Schistosoma mattheei and concurrent STIs raise questions as to the long-term effectiveness of the current control strategies of the National Control Programme to eliminate schistosomiasis as a public health problem. Improved availability of and regular accessibility to praziquantel treatment for women at risk such as this are urgently needed. Furthermore, targeted health education, increased community awareness, and dovetailing of synergistic activities and strategies with other health stakeholders such as those in sexual and reproductive health, as well as HIV/AIDS programs in the Ministry of Health, are needed here and in neighboring countries

Development, validation, and pilot application of a high throughput molecular xenomonitoring assay to detect Schistosoma mansoni and other trematode species within Biomphalaria freshwater snail hosts

Schistosomiasis is a neglected tropical disease (NTD) caused by infection with parasitic trematodes of the genus Schistosoma that can lead to debilitating morbidity and mortality. The World Health Organization recommend molecular xenomonitoring of Biomphalaria spp. freshwater snail intermediate hosts of Schistosoma mansoni to identify highly focal intestinal schistosomiasis transmission sites and monitor disease transmission, particularly in low-endemicity areas. A standardised protocol to do this, however, is needed. Here, two previously published primer sets were selected to develop and validate a multiplex molecular xenomonitoring end-point PCR assay capable of detecting S. mansoni infections within individual Biomphalaria spp. missed by cercarial shedding. The assay proved highly sensitive and highly specific in detecting and amplifying S. mansoni DNA and also proved highly sensitive in detecting and amplifying non-S. mansoni trematode DNA. The optimised assay was then used to screen Biomphalaria spp. collected from a S. mansoni-endemic area for infection and successfully detected S. mansoni infections missed by cercarial shedding as well as infections with non-S. mansoni trematodes. The continued development and use of molecular xenomonitoring assays such as this will aid in improving disease control efforts, significantly reducing disease-related morbidities experienced by those in schistosomiasis-endemic areas

Challenges in the diagnosis and control of female genital schistosomiasis in sub-Saharan Africa: an exemplar case report associated with mixed and putative hybrid schistosome infection in Nsanje District, Southern Malawi

Female genital schistosomiasis (FGS) remains an often overlooked chronic complication of urogenital schistosomiasis in adolescent girls and women. Moreover, the role of zoonotic or hybrid schistosome infection(s) is poorly appreciated, but is increasingly becoming an emerging public health concern in sub-Saharan Africa. In Southern Malawi, during the “Hybridization in UroGenital Schistosomiasis (HUGS)” study visit, we describe the case of a 33-year-old woman with suspected FGS who partook in a detailed external assessment with internal cervical examination using a portable colposcope. She provided several biological samples for analysis with traditional and molecular parasitological methods—urine, cervicovaginal lavage (CVL), cervical swabs, and external mass and cervical biopsies—alongside provision of detailed demographic information after a thorough medical history questionnaire and an in-depth interview. These samples were screened for the presence of Schistosoma ova on microscopy and DNA genotyping using a novel real-time PCR assay in parallel to pre-published probe-based PCR assays capable of identifying and discriminating up to six named Schistosoma species. A further molecular screen of sexually transmitted infections (STIs) including Trichomonas vaginalis, Chlamydia spp., and human papilloma virus (HPV) was conducted on her genital swab and CVL. Overt FGS was diagnosed on clinical colposcopy alongside inspection of the cervical biopsy by microscopy, real-time PCR, and histopathology. The urine filtration, microscopy and real-time PCR of the CVL and swab were negative. This evidences the typical diagnostic challenge, and cases such as this will pose an unmet need in satisfactory patient management. In addition to Schistosoma haematobium, the presence of the zoonotic species Schistosoma mattheei and concurrent STIs raise questions as to the long-term effectiveness of the current control strategies of the National Control Programme to eliminate schistosomiasis as a public health problem. Improved availability of and regular accessibility to praziquantel treatment for women at risk such as this are urgently needed. Furthermore, targeted health education, increased community awareness, and dovetailing of synergistic activities and strategies with other health stakeholders such as those in sexual and reproductive health, as well as HIV/AIDS programs in the Ministry of Health, are needed here and in neighboring countries

Detection of male genital schistosomiasis (MGS) associated with human, zoonotic and hybrid schistosomes in Southern Malawi

Background Male Genital Schistosomiasis (MGS) remains an often-overlooked chronic sequela of urogenital schistosomiasis in endemic areas of sub-Saharan Africa. As part of a 2-year longitudinal study on Hybridization of UroGenital Schistosomiasis (HUGS) in Malawi, a MGS sub-study was conducted to assess whether hybrid schistosomes were incriminated. Methods During recruitment, demographic, health and socio-economic data were collected through individual questionnaire interviews in Mthawira community from Nsanje District along Shire River and Samama community from Mangochi District along Lake Malawi shoreline. Urine and semen samples were collected and analysed to determine the identity of schistosome infection. Urine filtration and microscopy, direct microscopy of semen and its sediments (after centrifugation) were performed. Thereafter, the sediments were examined by molecular DNA analysis with a novel two-tube real-time PCR assay. The participants were also screened for Human papilloma virus (HPV) and other sexually transmitted infections (STIs). Results Twenty-two men were recruited for the sub-study, 8 in Nsanje District and 14 in Mangochi District, with a median age of 22.0 years. By microscopy, ten (45.7%) participants had Schistosoma ova in their urine, 11 (50.0%) in semen while 16 (72.7%) were positive by real-time PCR. One participant had both S. haematobium and S. mattheei ova in his semen, three showed symptoms, and one had a mixed infection of S. mansoni and possible S. haematobium-S. mattheei hybrid. Twelve men had detectable high-risk HPV serotypes 16, 18 and others while six had Trichomonas vaginalis and other STIs. Conclusion Zoonotic and hybrid schistosomes can cause MGS similar to human schistosomes, which can be co-infected with HPV and STIs, thereby posing a new challenge in diagnosis, management and control measures in resource poor settings. Increased awareness of these infections among local communities and primary healthcare workers and improvement of disease management are needed and advocated