|
| Epidemiological indexes |
| Population age |
| Gender |
| Individual immunological status |
| Geographical distribution and ethnic group |
|
| Human activities |
| Hygienic and diet practices |
| Rural and urban settings |
| Human waste contamination |
| Livestock pollution |
| Water treatment systems; food preparation styles and procedures |
| Travels, immigration |
|
| Environmental and social affecting factors |
| Animal pollution |
| Famine, malnutrition, dehydration |
| Geography, international adoptions |
| Calamities (typhoons, local wars, floods, etc) |
| Climate variation, pollution, deforestation and seasonal rains |
|
| Under-ascertainment factors in surveillance |
| Improper sampling of contaminated water systems and food |
| Difficulty to identify the likely source of infection |
| Misidentification of outbreak sources |
| Multiple protozoan coinfections |
|
| Under-ascertainment factors in clinics and diagnosis |
| Poor or diversified symptom presentations and low clinician’s sensitivity to consider protozoa as agents of gastrointestinal infections |
| Limited inclusion of protozoan searching in operational diagnostic workflows |
| Self-limiting infection course in immunocompetent adults and children |
| Low inclusion of advanced molecular tools for routine diagnosis |
|
