1. Water and Health Research Centre, University of Bristol, Merchant Ventures Building, Woodland Road, Bristol, BS8 1UB, UK
2. Department of Geography, University of Southampton, Highfield, Southampton, SO17 1BJ, UK
3. Department of Epidemiology and Preventive Medicine, Royal College of Surgeons in Ireland, Mercer Building, Dublin 2, Ireland
4. Natural Resources and the Environment, CSIR, PO Box 395, Pretoria, 0001, South Africa
5. Natural Resources and the Environment, CSIR, PO Box 320, Stellenbosch, 7599, South Africa
6. Institute of Water and Sanitation Development, PO Box MP 422 Mount Pleasant, Harare, Zimbabwe
7. Department of Animal Science, University of Zimbabwe, Mount Pleasant, Harare, Zimbabwe
8. Department of Microbiology, University of Venda, Thohoyandou, Limpopo Province, South Africa