WATER, SANITATION,
& HYGIENE
Empowering communities with WASH
for a healthier, sustainable future

Enteropathogen exposure: Ingestion or contact with pathogenic microorganisms such as bacteria, viruses, and parasites that infect the gastrointestinal tract and cause illnesses, particularly diarrheal diseases. These pathogens are commonly transmitted through contaminated water, food, poor sanitation, and inadequate hygiene practices.

Health Impact: Leads to gut pathology.

Helminth infection: An infestation by parasitic worms, commonly found in contaminated soil, water, and food, affecting the gastrointestinal tract, lungs, and other organs. These infections are prevalent in tropical and subtropical regions.

Environmental Enteric Dysfunction (EED): is a chronic inflammatory condition of the small intestine caused by continuous exposure to contaminated food, water, and poor sanitation.

Key Characteristics of EED:

• Damage to the intestinal lining allows toxins and pathogens to enter the bloodstream, leading to chronic inflammation.
• The damaged gut lining impairs the absorption of essential nutrients, contributing to malnutrition and stunting in children.
• Persistent exposure to bacteria and enteropathogens leads to low-grade inflammation, weakening the immune system and increasing the risk of infections.
• Disruptions in the gut microbiota reduce the body's ability to digest and absorb nutrients properly.

Bacterial Enteric Infections: Caused by pathogenic bacteria that infect the intestines, leading to inflammation, diarrhea, and other gastrointestinal symptoms.

Common Bacterial Pathogens:

• Escherichia coli (E. coli) causes diarrhea
• Salmonella spp. – Causes foodborne illness and typhoid fever (Salmonella Typhi).
• Shigella spp. – Causes bacillary dysentery (Shigellosis), leading to bloody diarrhea.
• Vibrio cholerae – Causes cholera, characterized by severe watery diarrhea.
• Campylobacter jejuni – A common cause of bacterial diarrhea
• Helicobacter pylori – Associated with gastric ulcers but also linked to enteric infections

Viral Enteric Infections: Caused by viruses that primarily infect the intestines, leading to acute gastroenteritis. Viral infections are highly contagious and often spread rapidly in communities.

Common Viral Pathogens:

• Rotavirus – A leading cause of severe diarrhea in children under five.
• Norovirus – Highly contagious; responsible for outbreaks in crowded places.
• Adenovirus – Can cause gastroenteritis, respiratory illness, and conjunctivitis.
• Astrovirus – Affects young children and the elderly, causing mild diarrhea.

Protozoal Enteric Infections: Caused by single-celled parasites (protozoa) that infect the intestines, often leading to prolonged diarrhea and malabsorption.

Common Protozoal Pathogens:

• Giardia lamblia – Causes giardiasis, leading to chronic diarrhea and malnutrition.
• Cryptosporidium spp. – Causes cryptosporidiosis, a severe diarrheal disease, especially in immunocompromised individuals.
• Entamoeba histolytica – Causes amoebiasis, leading to bloody diarrhea and liver abscesses.
• Cyclospora cayetanensis – Causes cyclosporiasis, leading to prolonged diarrhea, often linked to contaminated fresh produce.

Iron Malabsorption Due to Gut Inflammation: Chronic gut inflammation from EED reduces iron absorption, even when dietary intake is adequate. Hepcidin, a liver-produced hormone, increases in response to inflammation, blocking iron uptake in the intestines.This results in iron-deficiency anemia, a condition where the body lacks sufficient iron to produce red blood cells.

Parasitic Infections and Blood Loss: Helminth infections (hookworms, schistosomiasis, Trichuris trichiura) cause intestinal bleeding and chronic blood loss, leading to severe anemia.

Diarrhea, Malnutrition, and Micronutrient Deficiencies: Recurrent diarrhea from enteric infections reduces nutrient retention, leading to iron, folate, and vitamin B12 deficiencies, all essential for red blood cell production.

Zinc Deficiency and Impaired Growth: Zinc is essential for cell division, protein synthesis, and immune function. Low zinc levels weaken intestinal integrity, leading to poor nutrient absorption. Zinc deficiency increases infection risk (e.g., diarrhea), further impairing nutrient uptake and slowing growth.

Iron Deficiency and Growth Delays: Iron is crucial for oxygen transport, muscle development, and brain function. Anemia (iron deficiency) reduces oxygen supply to tissues, leading to fatigue, weakness, and slowed physical development.

Vitamin A Deficiency and Immune Suppression: Vitamin A supports bone growth, immune response, and vision. Deficiency increases susceptibility to infections (e.g., diarrhea, measles), which divert energy away from growth. Repeated infections in early childhood contribute to growth failure and stunting.

Iodine Deficiency and Brain Development: Iodine is essential for thyroid hormone production, which regulates growth and metabolism. Severe iodine deficiency during pregnancy and infancy leads to cretinism (severe stunting and cognitive impairment). Mild deficiencies cause suboptimal growth, delayed puberty, and learning difficulties.

Protein and Energy Malnutrition (PEM): Macronutrients (carbohydrates, proteins, and fats) fuel growth and tissue development. Protein deficiency disrupts muscle formation, bone strength, and immune responses, leading to stunting and wasting.

Impact on School:

• Delayed school enrollment.
• Repeated absenteeism.
• Lethargy and social withdrawal.
• Delayed motor development including fine motor skills.
• Minimal exploration of environment.
• Low academic performance.
• Leading to increase in school dropout rate.