PATHOGEN ANALYSIS, MONITORING AND SURVEILLANCE

1. PATHOGEN ANALYSIS, MONITORING AND SURVEILLANCE Pathogen detection is technically demanding, often tedious, slow to produce results, unreliable and expensive. • Done routinely in the health care field (clinical diagnostic microbiology): • often essential to patient treatment and care. • provides national surveillance of infectious disease epidemiology • Rarely done for monitoring or managing water quality • pathogen occurrence surveys and special studies: • survey (18 months) for Giardia, Cryptosporidium and enteric viruses in larger drinking water supplies using surface water sources: ICR (Information Collection Regulation) • survey for enteric viruses in ground water sources of drinking water (data base for Ground Water Disinfection Rule) • investigation of waterborne outbreaks

2. MICROBIAL INDICATORS OF FECAL CONTAMINATION • Traditional approach to protect/assess the "sanitary" quality of water (food) with respect to fecal contamination. • Quantify bacteria commonly present in intestines of warm blooded animals; high numbers; easy to measure; surrogates for pathogens, especially bacterial pathogens. • May not be reliable indicators of viruses and parasites.

3. Criteria for an Ideal Indicator of Fecal Contamination Applicable to all types of water (and other relevant samples). Present in feces, sewage and fecally contaminated samples when pathogens are present; numbers correlate with amount of fecal contamination; outnumber pathogens. No "aftergrowth" or "regrowth" in the environment. Survive/persist > than or = to pathogens. Easily detected/quantified by simple lab tests in a short time. Constant characteristics. Harmless to humans and other animals. Numbers in water (food, etc..) are associated with risks of enteric illness in consumers (dose-response relationship).

4. The Quest for The Ideal Indicator(s) • No single indicator (so far discovered) meets all of the criteria of an ideal indicator. • It is unlikely that a single organism or (taxonomic) group will meet all of the indicator criteria when applied to viruses, bacteria and parasites. • Furthermore, current microbial indicator criteria do not address those pathogens that are not associated with fecal contamination.

5. Current and Candid Bacterial Indicators of Fecal Contamination • Total coliforms: standards for drinking, bathing and shellfish • harvesting waters; not feces‑specific (environmental sources). • Fecal ("thermotolerant") coliforms: ditto for total coliforms. • E. coli: the "fecal" coliform; may occur naturally in tropics. • Fecal streptococci: another group of enteric, fecally excreted bacteria; not feces‑specific (environmental sources). • Enterococci: Streptococcus faecalis and S. faecium; a sub‑set of the fecal streptococci considered more feces‑specific; EPA guide-line for bathing water quality used as standards in some states. • Clostridium perfringens: anaerobe; ?feces‑specific?; very (too?) resistant spores; candidate indicator for protozoan cysts.

6. Current and Candid Bacterial Indicators of Fecal Contamination • Other Enteric, Anaerobic Bacteria: Bacteroides spp. and Bifidobacteria spp.; plentiful in feces (outnumber coliforms and fecal streptococci by 10-1000X); poor survival; poor detection and assay methods. • Some species of Bacteriodes may be unique to human or non-human fecal contamination • Indicators of Animal Fecal Contamination: • Rhodococcus coprophilus and similar ruminant bacteria • Unique to ruminants

7. Microbial Indicators of Fecal Contamination and Treatment Efficacy for Enteric Protozoan Pathogens • Clostridium perfringens spores may be useful indicators of enteric protozoan parasites • Plentiful in feces, raw sewage, treated effluents and receiving waters and soils. • Spores of aerobic bacilli (Bacillus spp.) may be useful indicators of water treatment efficacy • Plentiful in water and other environmental media • But, not feces-specific • Spores are reduced less than are conventional vegetative indicator bacteria by water and sewage treatment processes. • Spores of C. perfringens and Bacillus spp. superficially resemble enteric protozoan parasite cysts and oocysts.

8. CANDIDATE VIRAL INDICATORS OF FECAL CONTAMINATION OF WATER Coliphages: viruses (bacteriophages) infecting E. coli and perhaps other coliforms; attach directly to cell wall (somatic) heterogeneous group; may not be feces-specific; host-dependent detection. Male-specific (F+) coliphages: coliphages infecting "male" strains of E. coli (posses pili); may be feces-specific. May distinguish human from animal fecal contamination by group classification (II & III human; I & IV animal); but, pigs may harbor groups II & III, too. Bacteroides fragilis phages: may be human feces specific; USA studies do not show human-specificity; concentrations too low. Salmonella phages: in human and animal feces; may indicate presence of Salmonella bacteria; concentrations too low.

9. Male-specific and Somatic Coliphage Hosts and Phages Male-specific host Somatic host E. coli Famp Somatic Coliphage F+ E. coli C Somatic Coliphage F+ Coliphage F+ Coliphage

10. Pathogen Concentrations in Wastewater (Raw Sewage) • Highly variable and influenced by many factors: • Types and prevalence of enteric infections in the population. • Geographic, seasonal and climatological factors, • "Strength" and age of the sewage. • More water use, weaker sewage. • "Guesstimated Worstcase" Pathogen Concentrations in U.S. Raw Sewage (No./L): • -Enteric Viruses and Protozoan Cysts: ~ 10,000 of Each Group/Liter. • -Enteric Bacteria: ~100,000/Liter.