Stefano Catalano

Project Title: The interplay of wildlife, livestock and humans in novel hybrid zoonotic schistosomiasis transmission dynamics in Africa

ABout Stefano: After graduation in Veterinary Medicine in 2010 with a thesis on gastrointestinal parasite communities of wild hares, my passion for wildlife and their parasites brought me to Canada. There, I had the incredible opportunity to work on coyotes and their role in the transmission cycle of echinococcosis, and to complete a MSc thesis-based program with a project on hookworms and other parasites of grizzly and black bears.

I am delighted to be part of the ZELS studentship programme. This experience will further my training in parasitology at the human-wildlife interface within a One Health initiative, and it will allow me to build experience on the epidemiology and evolution of zoonotic parasites. I look forward to being part of this collaborative research project between the Royal Veterinary College, the Natural History Museum and the Université Gaston Berger. The researchers involved will provide me with all the support necessary not only to further my expertise in the, but also to interact with local communities and raise awareness through public outreach.

Contact Stefano: scatalano@rvc.ac.uk

Project Outline: Schistosomiasis is a Neglected Tropical Disease (NTD) of profound medical and veterinary importance across many parts of the world, with the greatest burden within sub-Saharan Africa (SSA). Anthropogenic changes in selective pressures following, for instance, new dam constructions, altered agricultural practices, and mass drug administration programs, may all impact the availability of suitable definitive and intermediate hosts for schistosomes and the potential for mixed species co-infections within such hosts (1-2). Additionally, within-Genera co-infections can introduce the potential for heterospecific (between-species) pairing in dioceous organisms such as schistosomes, resulting in either parthenogenesis (asexual reproduction where eggs occur without fertilization) or introgression (the introduction of genes from one species into that of another) and the production of hybrid offspring.

Whilst Schistosoma haematobium, the causative agent of urogenital schistosomiasis, was believed to be an exclusively human-specific parasite, our recent molecular studies on parasites obtained from human definitive hosts and snail intermediate hosts in West Africa have confirmed bidirectional hybridization between human urogenital S. haematobium with the animal (cattle, goat and sheep) intestinal schistosome species S. bovis and S. curassoni (3). Identification of such novel zoonotic hybrids have yet, however, to be isolated from within the livestock potential definitive hosts themselves - and is one of the main aims of the ZEL-funded grant to which this studentship is associated. Furthermore, we may also predict the natural hybridization between S. haematobium group parasites of human and their domestic livestock to occur, and potentially establish, within certain wildlife species, in particular rodent and other small mammal schistosome species

This doctoral research project thereby aims to elucidate the potential role of wildlife and livestock in the epidemiology, evolution and potential control of novel zoonotic schistosomes occurring through the viable hybridization of human and animal schistosome species. Focusing within Senegal, this multidisciplinary studentship incorporates tropical parasitological and behavioural field work with molecular diagnostics. The results obtained will be of substantial theoretical and applied importance for understanding multi-host disease transmission dynamics and control.

Supervisors: Prof Joanne Webster (Main supervisor, Royal Veterinary College), Dr Mariama Sene-Wade (Universite de Gaston Berger, Senegal) and Dr David Rollinson (Natural History Museum, UK)