John Changalucha

Co-Principal Investigator

Jennifer Downs

Co-Principal Investigator

Jane Maganga

Study Coordinator

Comparisons in genital mucosal immune cell populations, gene expression, and impaired anti-viral immunity in women with and without female genital schistosomiasis before and after praziquantel treatment


Schistosomiasis, a parasitic infection that affects over 200 million people worldwide, causes genital mucosal damage in women that is poorly responsive to anti-schistosome treatment with praziquantel. Schistosome worms lay eggs that migrate throughout the body. During Schistosoma haematobium infection, eggs preferentially migrate to the female genital mucosa, where they cause ulcerations and inflammation, a condition known as female genital schistosomiasis (FGS). Available data from our preliminary research indicate the occurrence of alterations in genital mucosal immune cell populations and gene expression in women with FGS and potential increased susceptibility to genital tract viral infections. Greater understanding is needed to establish how these alterations could increase viral infections, and whether they are reversible with anti-schistosome praziquantel treatment. We are studying these questions in a cohort of women with and without S. haematobium infection in northwest Tanzania with a long-term goal of identifying new strategies to improve treatment of FGS in women.

Primary objective

The study has 3 objectives; (a) To determine the impact of S. haematobium infection on immune cell populations of the cervical mucosa using spectral flow cytometry. (b) To determine the effect of S. haematobium infection on genital mucosal epithelial tissue integrity using RNA-Seq of cervical epithelial cells collected with cervical cytobrushing and isolated from other cell populations via bead-based magnetic separation. (c) To determine the effect of S. haematobium infection on the frequency, intensity, and duration of genital HSV-2 reactivation.


This is a cohort study conducted in Itilima district, northwestern Tanzania, where S. haematobium is endemic. Women aged 18 – 50 years are screened and those eligible are recruited and followed for 12 months. We aim to develop a cohort of 180 women grouped by S. haematobium infection status, those with confirmed S. haematobium infection and those without infection, who are followed at month 1, 2, 4, 6, 9, and 12. Women are treated for schistosome infections if found positive, and undergo gynaecological examinations and sample collection at baseline and follow up visits. Women are also screened for HSV-2 infection and perform swab self-collection to quantify HSV-2 in genital samples.


MITU, Tanzania/London School of Hygiene & Tropical Medicine, UK: Saidi Kapiga, Philip Ayieko; Catholic University of Health and Allied Sciences, Tanzania: Humphrey Mazigo; Leiden University Medical Center, Netherlands: Maria Yazdanbakhsh, Paul Corstjens; Weill Cornell Medical College, USA: Myung Hee Lee

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