Schistosomiasis and Infertility in East Africa

Female genital schistosomiasis (FGS) in returned travellers - A review of reported cases

INTRODUCTION

Female genital schistosomiasis (FGS) is the manifestation of schistosomiasis in the lower and the upper reproductive organs. In endemic areas FGS is frequent with a tremendous impact on reproductive health. Anecdotal observations indicate that FGS also occurs in travellers who became infected when exposing themselves in natural water bodies in endemic areas. The objective of this study is to summarize existing knowledge on FGS in travellers with a focus on FGS-associated morbidity, diagnosis, and treatment.

MATERIAL AND METHODS

The PubMed database was searched for reports on FGS in travellers from 1980 to 2023. Case reports of FGS in travellers were identified and reviewed.

RESULTS

Thirty-eight case reports were identified. The most common manifestation of FGS were lesions at the vulva (n = 16), the cervix (n = 11), the ovaries and Fallopian tubes (n = 6), the vagina (n = 3) and the endometrium (n = 2). With a few exceptions the diagnosis was spurious. 15 patients with vulval schistosomiasis were treated with the anti-helminthic drug praziquantel (i.e. 40 mg/kg) in 1-3 doses. In all but one patient the lesions disappeared three to six months after treatment.

CONCLUSIONS

This study shows that FGS in travellers exhibits the same disease manifestations as in FGS patients living in endemic areas. However, correct diagnosis was established after months to years delaying treatment and cure. This precludes the inclusion of FGS in diagnostic guidelines for female travellers returning from endemic areas for schistosomiasis.

Assessing urogenital schistosomiasis and female genital schistosomiasis (FGS) among adolescents in Anaocha, Anambra State, Nigeria: implications for ongoing control efforts

BACKGROUND

Urogenital schistosomiasis (UgS) remains a persistent health challenge among adolescents in Anambra State, Nigeria, despite ongoing control efforts. Mass praziquantel treatment programs, initiated in 2013, primarily target primary school-aged children (5-14 years old), leaving adolescents (10-19 years old) enrolled in secondary schools vulnerable to urogenital schistosomiaisis. Additionally, the extent of female genital schistosomiasis (FGS), a neglected gynaecological manifestation of UgS remains unclear.

METHODOLOGY

To address these gaps, a cross-sectional study was conducted in Anaocha Local Government Area from February to May 2023. Four hundred and seventy consenting adolescents aged 10-19 years were enrolled. Urinalysis including urine filtration was employed to confirm haematuria and detect urogenital schistosomiasis (UGS) among the participants. For females with heavy infections (≥ 50 eggs/10 ml urine), a gynaecologist performed colposcopy examinations, complemented by acetic acid and Lugol's iodine staining to assess for female genital schistosomiasis (FGS) lesions or other related reproductive health conditions. Socio-demographic data, including information on potential risk factors, were systematically collected using the Kobo ToolBox software, following gender-sensitive data collection guidelines. Data were analysed using SPSS version 25, incorporating descriptive statistics, multinomial logistic regression, odds ratios, and significance testing.

RESULTS

Among the 470 adolescents (52.8% females, 47.2% males) examined, an overall UgS prevalence of 14.5% was observed, with an average of 5.25 eggs per 10 ml of urine. Females had a slightly higher prevalence (16.1%), and 7.5% had heavy infections. Although gender differences in infection rates were not statistically significant, males had slightly higher odds of infection (OR: 1.332; 95% CI: 0.791-2.244; p-value: 0.280). Adolescents aged 10-14 had the highest prevalence, with significantly increased odds of infection (OR: 1.720; 95% CI: 1.012-2.923; p-value: 0.045). Colposcopy examinations of females with heavy infections revealed FGS lesions and co-infections with Trichomonas vaginalis. Haematuria, though prevalent (24.6%), was not the sole indicator, as those without it faced significantly higher odds of infection (OR: 2.924; 95% CI: 1.731-4.941; p-value: 0.000). Dysuria and genital itching/burning sensation were other UgS and FGS associated symptoms. Direct water contact was associated with higher infection odds (OR: 2.601; 95% CI: 1.007-6.716; p-value: 0.048). Various risk factors were associated with UgS.

CONCLUSION

The study highlights the need for a comprehensive Urogenital Schistosomiasis (UGS) control strategy that includes secondary school adolescents, emphasizes risk factor management, promotes safe water practices, and raises awareness about UGS and Female Genital Schistosomiasis (FGS) among adolescents, thus improving control efforts and mitigating this health challenge in the region.

Beyond schistosomiasis: unraveling co-infections and altered immunity

Schistosomiasis is a neglected tropical disease caused by the helminth Schistosoma spp. and has the second highest global impact of all parasites. Schistosoma are transmitted through contact with contaminated fresh water predominantly in Africa, Asia, the Middle East, and South America. Due to the widespread prevalence of Schistosoma, co-infection with other infectious agents is common but often poorly described. Herein, we review recent literature describing the impact of Schistosoma co-infection between species and Schistosoma co-infection with blood-borne protozoa, soil-transmitted helminths, various intestinal protozoa, Mycobacterium, Salmonella, various urinary tract infection-causing agents, and viral pathogens. In each case, disease severity and, of particular interest, the immune landscape, are altered as a consequence of co-infection. Understanding the impact of schistosomiasis co-infections will be important when considering treatment strategies and vaccine development moving forward.

Male genitourinary schistosomiasis-related symptoms among long-term Western African migrants in Spain: a prospective population-based screening study

BACKGROUND

Schistosomiasis is highly endemic in sub-Saharan Africa and frequently imported to Europe. Male urogenital manifestations are often neglected. We aimed to ascertain the prevalence of genitourinary clinical signs and symptoms among long-term African migrants in a non-endemic European country using a serology test.

METHODS

We carried out a prospective, community-based cross-sectional study of adult male migrants from sub-Saharan Africa living in Spain. Schistosoma serology tests and microscopic urine examinations were carried out, and clinical data were obtained from an electronic medical record search and a structured questionnaire.

RESULTS

We included 388 adult males, mean age 43.5 years [Standard Deviation (SD) = 12.0, range: 18-76]. The median time since migration to the European Union was 17 [Interquartile range (IQR): 11-21] years. The most frequent country of origin was Senegal (N = 179, 46.1%). Of the 338, 147 (37.6%) tested positive for Schistosoma. Parasite eggs were present in the urine of only 1.3%. Nine genitourinary clinical items were significantly associated with positive Schistosoma serology results: pelvic pain (45.2%; OR = 1.57, 95% CI: 1.0-2.4), pain on ejaculation (14.5%; OR = 1.85, 95% CI: 1.0-3.5), dyspareunia (12.4%; OR = 2.45, 95% CI: 1.2-5.2), erectile dysfunction (9.5%; OR = 3.10, 95% CI: 1.3-7.6), self-reported episodes of infertility (32.1%; OR = 1.69, 95% CI: 1.0-2.8), haematuria (55.2%; OR = 2.37, 95% CI: 1.5-3.6), dysuria (52.1%; OR = 2.01, 95% CI: 1.3-3.1), undiagnosed syndromic STIs (5.4%), and orchitis (20.7%; OR = 1.81, 95% CI: 1.0-3.1). Clinical signs tended to cluster.

CONCLUSIONS

Urogenital clinical signs and symptoms are prevalent among male African long-term migrants with a positive Schistosoma serology results. Genital involvement can be frequent even among those with long periods of non-residence in their sub-Saharan African countries of origin. Further research is needed to develop diagnostic tools and validate therapeutic approaches to chronic schistosomiasis.

Female genital schistosomiasis is a neglected public health problem in Tanzania: Evidence from a scoping review

Schistosoma haematobium, the parasite that causes urogenital schistosomiasis, is widely prevalent in Tanzania. In addition to well-known effects on the urinary tract, S. haematobium also causes clinically- evident damage to the reproductive tract in approximately half of infected women, which is known as female genital schistosomiasis (FGS). FGS has major gynecologic and social consequences on women's reproductive health, yet little information is available regarding FGS in Tanzania. To cover that gap, we conducted the present scoping review to examine the epidemiology of FGS in Tanzania (both in the mainland and Zanzibar island) and to make recommendations for future work in this area. The available evidence from community-based and hospital-based retrospective studies indicates that FGS is a significant health problem in the country. Very few community-based studies have been reported from mainland Tanzania, and Zanzibar. Our review highlights the scarcity of efforts to address FGS in Tanzania and the need for additional community-based studies. The studies will help us understand the true burden of the disease nationwide, to assess the impact of praziquantel on FGS lesions, and to address social and mental health in relation to FGS. This review emphasizes integration of delivery of FGS related services in primary health care systems through the reproductive health clinics which covers sexually transmitted infections, HIV and cervical cancer screening. These actions are essential if this neglected gynecological disease is to be addressed in Tanzania.

Knowledge, experiences, and practices of women affected by female genital schistosomiasis in rural Madagascar: A qualitative study on disease perception, health impairment and social impact

BACKGROUND

Female genital schistosomiasis (FGS) is a neglected manifestation of urogenital schistosomiasis caused by S. haematobium. The disease presents with symptoms such as pelvic pain, vaginal discharge and bleeding and menstruation disorders, and might lead to infertility and pregnancy complications. The perspectives of women with FGS have not been studied systematically. The aim of the study was to understand knowledge, experiences, and practices of women with FGS.

METHODS

We performed a qualitative study with seventy-six women diagnosed of having FGS, in the Ambanja district in Northwest Madagascar. Data collection was either through focus group discussion (N = 60) or in an individual semi-structured interview (N = 16). FGS was diagnosed by colposcopy. The data was analysed using Mayring´s qualitative content analysis.

RESULTS

Knowledge on how the disease is acquired varied and ideas on prevention remained vague. Patients suffered from vaginal discharge and pelvic complaints. Some women expressed unbearable pain during sexual intercourse and compared their pain to an open wound being touched. FGS considerably impaired women´s daily activities and their quality of life. Infertility led to resignation and despair, conflicts with the partner and to social exclusion from the community. Women fearing to sexually transmit FGS refrained from partnership and sexual relations. Many women with FGS reported stigmatisation. A coping strategy was to share strain with other women having similar complaints. However, concealing FGS was a common behaviour which led to social isolation and delayed health care seeking.

CONCLUSIONS

Our study underlines that FGS has an important impact on the sexual health of women and on their social life in the community. Our results highlight the importance of providing adequate health education and structural interventions, such as the supply of water and the provision of sanitation measures. Further, correct diagnosis and treatment of FGS in adolescent girls and women should be available in all S. haematobium-endemic areas.

TRIAL REGISTRATION

The qualitative study was embedded in a randomised controlled trial (RCT) in which two doses of praziquantel were compared (https://clinicaltrials.gov/ct2/show/NCT04115072).

Prevalence and factors associated with transmission of schistosomiasis in school-aged children in South Sudan: a cross-sectional study

Introduction

South Sudan is affected by a high burden of Neglected Tropical Diseases (NTDs). The country is very vulnerable to NTDs due to its favourable tropical climate and multiple risk factors. However, the distribution of the diseases and the populations at risk for the various NTDs is unknown. This paper described the distribution of schistosomiasis in 58 counties and 261 schools in South Sudan.

Methods

a descriptive quantitative cross-sectional study of schistosomiasis in 58 counties in 8 states of South Sudan recruited school-aged children. Using different laboratory techniques, the children were tested for Schistosoma mansoni (S. mansoni) and Schistosoma haematobium (S. haematobium). A quantitative descriptive statistical was performed to determine the prevalence rates and the endemicity of schistosomiasis among 13,286 school-aged children.

Results

the overall prevalence of S. mansoni and S. haematobium were 6.1% and 3.7% using Kato Katz and urine filtration concentration testing techniques. The highest state prevalence was reported in Western Equatoria for both S. mansoni (14.7%) and S. haematobium (7.3%). The age of the participants varied from 4 to 18 years; of these, children 10 to 12 years old had the highest prevalence of S. mansoni (6.8%) and S. haematobium (3.7%). The prevalence of S. mansoni (7% male vs 5% female) and S. haematobium (3.6% male vs 3.1% female) were higher in males than females. The likelihood of the prevalence of S. mansoni in males was 1.42 (95% CI:1.23, 1.64) higher than in females, while for S. haematobium, 1.36 (95% CI:1.12, 1.65) higher than in females. The prevalence of S. mansoni and S. haematobium showed a statistically significant gender difference (P< 0.05).

Conclusion

the study had provided evidence of the distribution of schistosomiasis in South Sudan for policy direction and recommended annual preventive chemotherapy with praziquantel in all endemic areas.

An update on female and male genital schistosomiasis and a call to integrate efforts to escalate diagnosis, treatment and awareness in endemic and non-endemic settings: The time is now

The last decades have brought important insight and updates in the diagnosis, management and immunopathology of female genital schistosomiasis (FGS) and male genital schistosomiasis (MGS). Despite sharing a common parasitic aetiological agent, FGS and MGS have typically been studied separately. Infection with Schistosoma haematobium manifests with gender-specific clinical manifestations and consequences of infection, albeit having a similar pathogenesis within the human genital tract. Schistosoma haematobium is a known urinary bladder carcinogen, but its potential causative role in other types of neoplasia, such as cervical cancer, is not fully understood. Furthermore, the impact of praziquantel treatment on clinical outcomes remains largely underexplored, as is the interplay of FGS/MGS with relevant reproductive tract infections such as HIV and Human Papillomavirus. In non-endemic settings, travel and immigrant health clinics need better guidance to correctly identify and treat FGS and MGS. Our review outlines the latest advances and remaining knowledge gaps in FGS and MGS research. We aim to pave a way forward to formulate more effective control measures and discuss elimination targets. With a growing community awareness in health practitioners, scientists and epidemiologists, alongside the sufferers from these diseases, we aspire to witness a new generation of young women and men free from the downstream disabling manifestations of disease.

Addressing a silent and neglected scourge in sexual and reproductive health in Sub-Saharan Africa by development of training competencies to improve prevention, diagnosis, and treatment of female genital schistosomiasis (FGS) for health workers

Background

Schistosomiasis is an acute and chronic disease caused by parasitic worms, that can take two main forms: intestinal or urogenital. If left untreated, the urogenital form can lead to female genital schistosomiasis (FGS) in women and girls; frequently resulting in severe reproductive health complications which are often misdiagnosed as sexually-transmitted infections (STIs) or can be confused with cervical cancer. Despite its impact on women’s reproductive health, FGS is typically overlooked in medical training and remains poorly recognized with low awareness both in affected communities and in health professionals. FGS has been described as the one of the most neglected sexual and reproductive health issues in sub-Saharan Africa (Swai in BMC Infect Dis 6:134, 2006; Kukula in PLoS Negl Trop Dis 13:e0007207; Joint United Nations Programme on HIV/AIDS (UNAIDS) 2019). Increased knowledge and awareness of FGS is required to end this neglect, improve women’s reproductive health, and decrease the burden of this preventable and treatable neglected tropical disease.

Methods

We conducted interactive virtual workshops, in collaboration with the World Health Organization (WHO), engaging 64 participants with medical and public health backgrounds from around the world to establish standardized skills (or competencies) for prevention, diagnosis, and treatment of FGS at all levels of the health system. The competencies were drafted in small groups, peer-reviewed, and finalized by participants.

Results

This participatory process led to identification of 27 skills needed for FGS prevention, diagnosis, and management for two categories of health workers; those working in a clinical setting, and those working in a community setting. Among them, ten relate to the diagnosis of FGS including three that involve a pelvic exam and seven that do not. Six constitute the appropriate behaviors required to treat FGS in a clinical setting. Eleven address the community setting, with six relating to the identification of women at risk and five relating to prevention.

Conclusion

Defining the skills necessary for FGS management is a critical step to prepare for proper diagnosis and treatment of women and girls in sub-Saharan Africa by trained health professionals. The suggested competencies can now serve as the foundation to create educative tools and curricula to better train health care workers on the prevention, diagnosis, and management of FGS.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12978-021-01252-2.

Schistosomiasis belongs to the group of neglected tropical diseases (NTDs) found in tropical and subtropical countries, disproportionately affecting poor populations with limited access to safe water and adequate sanitation. Female genital schistosomiasis (FGS) is a chronic disease caused by parasitic worms, schistososomes, transmitted by contact with infested fresh water. When left untreated, FGS can lead to severe reproductive health complications, such as sub-or infertility and ectopic pregnancy. FGS is a leading neglected issue in sexual and reproductive health in sub-Saharan Africa; however, health professionals are not familiar with it, leading to misdiagnosis and improper treatment. A critical challenge in addressing the burden of FGS is the knowledge gap about the disease in communities and health professionals in endemic areas and the world at large. As part of an FGS Accelerated Scale Together (FAST) package, and in an attempt to address the knowledge gap in health professionals, we organized an interactive workshop bringing together a group of 64 participants working in sexual and reproductive health generally, and/or FGS specifically. Together, we developed a comprehensive set of required skills for health workers training on FGS. The workshop participants drafted 27 skills (or competencies) to diagnose, treat, and prevent FGS. Establishing what health workers must know is a crucial first step towards the integration of FGS into women’s health care. The competencies are now available and can be used as a framework in the development of training for health professionals, opening the doors to better reproductive health for women.

Schistosomiasis with a Focus on Africa

Schistosomiasis is a common neglected tropical disease of impoverished people and livestock in many developing countries in tropical Africa, the Middle East, Asia, and Latin America. Substantial progress has been made in controlling schistosomiasis in some African countries, but the disease still prevails in most parts of sub-Saharan Africa with an estimated 800 million people at risk of infection. Current control strategies rely primarily on treatment with praziquantel, as no vaccine is available; however, treatment alone does not prevent reinfection. There has been emphasis on the use of integrated approaches in the control and elimination of the disease in recent years with the development of health infrastructure and health education. However, there is a need to evaluate the present status of African schistosomiasis, primarily caused by Schistosoma mansoni and S. haematobium, and the factors affecting the disease as the basis for developing more effective control and elimination strategies in the future. This review provides an historical perspective of schistosomiasis in Africa and discusses the current status of control efforts in those countries where the disease is endemic.

Effect of Lymphatic Filariasis and Hookworm Infection on Pregnancy Course and Outcome in Women Living in the Democratic Republic of the Congo

Little is known about the effect of helminth infections on the natural gynecological and pregnancy course. Our goal was to assess the relationship between Wuchereria bancrofti and hookworm (HW) infections with pregnancy course and outcome in a group of 82 women living in a rural area of the Democratic Republic of the Congo. Demographics and information on gynecological and obstetrical histories were collected retrospectively with standardized questionnaires. Wuchereria bancrofti and HW infections were diagnosed using a filarial antigen-detection test and the Kato-Katz method, respectively. Analyses consisted of multivariable logistic regressions adjusting for age, number of deliveries, and history of anthelmintic treatment (HAHT). The median age of study participants was 35 (interquartile range [IQR]: 30-44) years, and the median number of deliveries was five (IQR: 3-7). Wuchereria bancrofti and HW infection rates were 44.5% and 43.3%, respectively. Filarial antigenemia and HW infection were not significantly associated with the number of deliveries. The proportions of women with a history of pregnancy resulting in neonatal death, miscarriage, premature birth, and postpartum hemorrhage were 56%, 44%, 23%, and 36%, respectively. History of pregnancy associated with neonatal death was less frequent in women with HAHT, tended to be more frequent in women with filarial antigenemia, and was not associated with HW infection. None of the three other pregnancy events studied (miscarriage, premature birth, and postpartum hemorrhage) were associated with filarial antigenemia or HW infection. The positive association found between HAHT and lower risk of neonatal death warrants investigation in larger groups of women.

Rethinking the Top-Down Approach to Schistosomiasis Control and Elimination in Sub-Saharan Africa

The control and elimination of schistosomiasis have over the last two decades involved several strategies, with the current strategy by the World Health Organization (WHO) focusing mainly on treatment with praziquantel during mass drug administration (MDA). However, the disease context is complex with an interplay of social, economic, political, and cultural factors that may affect achieving the goals of the Neglected Tropical Disease (NTD) 2021-2030 Roadmap. There is a need to revisit the current top-down and reactive approach to schistosomiasis control among sub-Saharan African countries and advocate for a dynamic and diversified approach. This paper highlights the challenges of praziquantel-focused policy for schistosomiasis control and new ways to move from schistosomiasis control to elimination in sub-Saharan Africa. We will also discuss an alternative and diversified approach that consists of a Systems Thinking Framework that embraces intersectoral collaboration fully and includes co-creating locally relevant strategies with affected communities. We propose that achieving the goals for control and elimination of schistosomiasis requires a bottom-up and pro-active approach involving multiple stakeholders. Such a pro-active integrated approach will pave the way for achieving the goals of the NTD 2021-2030 roadmap for schistosomiasis, and ultimately improve the wellbeing of those living in endemic areas.

Association of schistosomiasis and HIV infections: A systematic review and meta-analysis

Background:

Female genital schistosomiasis (FGS) affects up to 56 million women in sub-Saharan Africa and may increase risk of HIV infection.

Methods:

To assess the association of schistosomiasis with HIV infection, peer-reviewed literature published until 31 December 2018 was examined and a pooled estimate for the odds ratio was generated using Bayesian random effects models.

Results:

Of the 364 abstracts that were identified, 26 were included in the summary. Eight reported odds ratios of the association between schistosomiasis and HIV; one reported a transmission hazard ratio of 1.8 (95% CI, 1.2–2.6) among women and 1.4 (95% CI, 1.0–1.9) among men; 11 described the prevalence of schistosomiasis among HIV-positive people (range, 1.5–36.6%); and six reported the prevalence of HIV among people with schistosomiasis (range, 5.8–57.3%). Six studies were selected for quantitative analysis. The pooled estimate for the odds ratio of HIV among people with schistosomiasis was 2.3 (95% CI, 1.2–4.3).

Conclusions:

A significant association of schistosomiasis with HIV was found. However, a specific summary estimate for FGS could not be generated. A research agenda was provided to determine the effect of FGS on HIV infection. The WHO’s policy on mass drug administration for schistosomiasis may prevent HIV.

Schistosoma haematobium ova in human semen: a case report

Objective

To report a rare case of schistosomiasis observed during semen evaluation.

Design

Case report.

Setting

University hospital.

Patient(s)

A 30-year-old man referred for semen analysis.

Interventions(s)

None.

Main Outcome Measures(s)

Poor sperm motility and viability.

Result(s)

The patient produced 9.8 mL of brown colored semen with a bad odor. Total and progressive sperm motility were 9% and 2%, respectively. Sperm concentration was 112 million/mL. Microscopic semen evaluation showed slight sperm agglutination, a large number of Schistosoma haematobium ova, extensive debris, and a large numberot of amorphous cells. Approximately 20 million/mL of neutrophils were observed in the ejaculate. The sperm viability was extremely low (13%). Sperm morphology was 6% normal, and most abnormal sperm had coiled tails in addition to other abnormalities.

Conclusion(s)

A microscopic examination of semen from suspected Schistosoma haematobium–infected patients may not only help in confirming diagnosis but may also highlight the underlying infertility due to this infestation. Such cases are rarely observed in andrology laboratories; therefore, it is important to train all testing staff on rare semen samples.

Beyond the barrier: Female Genital Schistosomiasis as a potential risk factor for HIV-1 acquisition

Female genital schistosomiasis (FGS) results from egg-deposition in the female reproductive tract primarily by the waterborne parasite Schistosoma (S.) haematobium, and less commonly by Schistosoma (S.) mansoni. FGS affects an estimated 20-56 million women worldwide, mostly in sub-Saharan Africa. There is cross-sectional evidence of increased HIV-1 prevalence in schistosomiasis-infected women, but a causal relationship between FGS and either HIV-1 acquisition or transmission has not been fully established. Beyond the pathognomonic breach in the cervicovaginal barrier caused by FGS, this narrative review explores potential mechanisms for a synergistic relationship between S. haematobium infection, FGS, and HIV-1 acquisition through vaginal inflammation and target cell recruitment.

Female Genital Schistosomiasis and HIV: Research Urgently Needed to Improve Understanding of the Health Impacts of This Important Coinfection

Evidence suggests that there are important interactions between HIV and female genital schistosomiasis (FGS) that may have significant effects on individual and population health. However, the exact way they interact and the health impacts of the interactions are not well understood. In this article, we discuss what is known about the interactions between FGS and HIV, and the potential impact of the interactions. This includes the likelihood that FGS is an important health problem for HIV-positive women in Schistosoma-endemic areas potentially associated with an increased risk of mortality, cancer, and infertility. In addition, it may be significantly impacting the HIV epidemic in sub-Saharan Africa by making young women more susceptible to HIV. We call for immediate action and argue that research is urgently required to address these knowledge gaps and propose a research agenda to achieve this.

Schistosomiasis and Infertility: What Do We Know?

There is increasing attention on the complex interactions occurring between schistosome parasites and their hosts. However, little is known about the occurrence, epidemiology, and mechanisms of schistosomiasis-associated infertility. In this article, we argue that an in-depth understanding of the interplay between parasites and the host endocrine system may significantly enhance current knowledge of infertility in infected individuals. We discuss the basic hormonal mechanisms that may lead to the discovery of entirely novel anthelmintic interventions against schistosomiasis.

Schistosomiasis is associated with incident HIV transmission and death in Zambia

Background

We examined relationships between schistosome infection, HIV transmission or acquisition, and all-cause death.

Methods

We retrospectively tested baseline sera from a heterosexual HIV-discordant couple cohort in Lusaka, Zambia with follow-up from 1994–2012 in a nested case-control design. Schistosome-specific antibody levels were measured by ELISA. Associations between baseline antibody response to schistosome antigens and incident HIV transmission, acquisition, and all-cause death stratified by gender and HIV status were assessed. In a subset of HIV- women and HIV+ men, we performed immunoblots to evaluate associations between Schistosoma haematobium or Schistosoma mansoni infection history and HIV incidence.

Results

Of 2,145 individuals, 59% had positive baseline schistosome-specific antibody responses. In HIV+ women and men, baseline schistosome-specific antibodies were associated with HIV transmission to partners (adjusted hazard ratio [aHR] = 1.8, p<0.005 and aHR = 1.4, p<0.05, respectively) and death in HIV+ women (aHR = 2.2, p<0.001). In 250 HIV- women, presence of S. haematobium-specific antibodies was associated with increased risk of HIV acquisition (aHR = 1.4, p<0.05).

Conclusion

Schistosome infections were associated with increased transmission of HIV from both sexes, acquisition of HIV in women, and increased progression to death in HIV+ women. Establishing effective prevention and treatment strategies for schistosomiasis, including in urban adults, may reduce HIV incidence and death in HIV+ persons living in endemic areas.

This study explored the association between schistosome infections (a disease caused by parasitic flatworms, also known as ‘snail fever’, which is very common throughout sub-Saharan Africa) and human immunodeficiency virus (HIV). We found in Lusaka, the capital of Zambia, that schistosome infections were associated with transmission of HIV from adult men and women, and schistosome infections were also associated with increased HIV acquisition in adult women. We additionally found that schistosome infections were associated with death in HIV+ adult women. Since treatment of schistosome infections with praziquantel is inexpensive, effective, and safe, schistosomiasis prevention and treatment strategies may be a cost-effective way to reduce not only the symptoms associated with the infection, but also new cases of HIV and death among HIV+ persons. Though often viewed as an infection of predominantly rural areas and children, this study highlights that schistosomiasis prevention and treatment efforts are also needed in urban areas and among adults.