Waterborne Cryptosporidium and Giardia in South Africa: A Critical Public Health Review

Waterborne protozoan pathogens, particularly Cryptosporidium and Giardia, remain significant public health concerns in South Africa, disproportionately affecting children, immunocompromised individuals, and rural populations. This review synthesises recent epidemiological, environmental, and diagnostic evidence, critically examining the occurrence, transmission pathways, and public health implications of these parasites. The widespread detection of (oo)cysts in drinking, recreational, and informal water sources highlights the limitations of conventional water treatment and monitoring systems, given the environmental persistence of both organisms and their resistance to chlorination. Although advanced molecular and immunological diagnostic methods are available in selected reference laboratories, their limited integration into national surveillance programmes contributes to underreporting and fragmented disease data. Key challenges include insufficient epidemiological information across many regions, inadequate diagnostic capacity, and the limited incorporation of protozoan monitoring into water quality regulation and public health policy. Addressing these gaps requires interdisciplinary approaches that integrate molecular epidemiology, environmental health, and social science perspectives to elucidate transmission dynamics and inform targeted interventions. Priority actions include strengthening protozoan surveillance, revising water quality standards, expanding the adoption of multi-barrier and advanced treatment technologies, and implementing a national One Health framework. Sustained collaboration among government, researchers, and communities is essential to improve water safety and protect vulnerable populations.