Drinking water can carry invisible threats harmful microorganisms that cause diseases ranging from mild diarrhea to life-threatening infections. In this article, we explore the main microbial contaminants found in drinking water, their health effects, and why understanding their behavior is crucial for public health.
Key Types of Microbial Contaminants
🦠 Bacteria
- Escherichia coli (E. coli) – an indicator of fecal contamination.
- Salmonella – causes diarrhea, fever, and cramps.
- Legionella – thrives in warm water systems, causing Legionnaires’ disease.
- Campylobacter – common in surface water, linked to gastrointestinal illness.
🧫 Protozoa
- Giardia intestinalis – leads to giardiasis, with prolonged diarrhea.
- Cryptosporidium parvum – highly resistant to chlorine, causes cryptosporidiosis.
- Naegleria fowleri – a rare but deadly brain-infecting amoeba.
🦠 Viruses
- Hepatitis A – affects the liver; spreads via contaminated food/water.
- Norovirus – highly contagious, causes vomiting and diarrhea.
- Enteroviruses – linked to polio-like symptoms and other infections.
Comparative Table of Waterborne Pathogens: Infectious Dose, Incidence, and Survival Strategies
Understanding the risks associated with microbiological contaminants in drinking water involves more than just identifying the pathogens. Key factors include their infectious dose, how frequently they cause illness in the population, how long they can survive in water, and the strategies they use to persist in harsh environments like treatment systems.
Here is a summarized version of data adapted from Ford (1999):
