August 2023: A HUGS milestone, completion of first annual follow-up

Blog 1 Sep 2023
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Between 19th June and 21st July the UK and Malawi HUGS teams were fully deployed in Nsanje and Mangochi. There we undertook our first annual human cohort follow-up. In total over 20 staff and auxiliary workers were united in this common effort. Indeed, this was a critical deployment for HUGS to ascertain current levels of schistosomiasis (re)infection in Mthawira and Samama villages. This was some 12-months after a community-wide distribution of praziquantel immediately after our baseline inspection. The delivery of medicines was in close association with the national control programme.

Prior to this follow-up, pre-survey HUGS teams, led by Peter Makaula, undertook numerous community sensitisation visits alongside preparatory steps in liaison with village health surveillance assistants. As this annual follow-up was to conduct our most detailed clinical surveys for female genital schistosomiasis (FGS) and male genital schistosomiasis (MGS), respectively, detailed reconsenting of selected participants was needed. Our clinical surveillance procedures included ultrasonography, clinical colposcopy and microscopy of semen, requiring specialist equipment alongside more demanding on-site needs for electricity to run these power-hungry machines.

 

With the hard work of the Nsanje and Mangochi field teams, upon completion of these surveys, HUGS achieved a project milestone. We were able to reexamine over 85% of the baseline study group, totalling over 2,100 individuals. Moreover, we undertook our first detailed clinical examinations of adults, some 50 women for female genital schistosomiasis (FGS) and some 30 men for male genital schistosomiasis (MGS). Despite prior praziquantel treatment, levels of egg-patent infection in urine remained substantial although some declines in the intensity of schistosome infection were noted.

Nevertheless, current prevalence of infection which was approaching 50% in each community, was higher than we would have wished. On the basis of our results, and upon ongoing discussions with the national control programme, we will conduct biannual treatment with praziquantel in the coming year. With this in mind, we remain hopeful to see some tangible parasitological gains in control at our second annual follow-up scheduled for June 2024. 

Scientific highlights included the demonstration of viable schistosome eggs in cervicovaginal lavage (CVL), as well as hatching miracidia in CVL as well as in semen, for later genotyping. Analyses of preliminary results are revealing the presence of S. mattheei in these samples, incriminating this schistosome in genital tract disease in both genders. This annual follow in Mangochi also provided a training window for two LSTM MSc students to join the field team – Christine Rice and Lenon Turner – who were each tasked with a project on human and animal schistosomiasis. 

Chrissie writes - I went to Mangochi for three weeks in July to investigate the presence of urogenital schistosomiasis – specifically FGS. Working with the HUGS clinician and nurses, I had the opportunity to observe gynaecological examinations and to help look for the presence of the telltale signs of FGS on the cervix/vaginal wall of patients, as well as analyse CVL by microscopy. Looking ahead, I hope to be able to continue doing work on schistosomiasis, whether it be at LSTM or elsewhere, as the control of FGS interests me greatly.   

Lenon writes – Part of the HUGS investigation is to characterise schistosomiasis in local livestock. Even though the main team was deployed on the human cohort inspection, I was able to work with Alex Juhasz and Ruth Cowlishaw on a small sub-study tracking schistosomiasis in local cattle, goats and sheep. While in Mangochi, I helped analyse faecal samples using the modified Pitchford and Visser funnel technique. I also undertook malacological surveys to search for shedding Bulinus snails. Our study demonstrated infections in cattle, goats and sheep, with hatched miracidia shown to be S. mattheei. Finding shedding snails also demonstrated the pervasive nature of this parasite in this lakeshore setting.