Environmental Transmission of Pathogenic Microbes why they

Environmental Transmission of Pathogenic Microbes – why they are where they are when they are Part 2 Dr. Julie Ann Kase Public Health Scientist – Bioterrorism and Emerging Pathogens Unit NC State Laboratory of Public Health Julie. Kase@ncmail. net

Environmental Monitoring of Pathogenic Microbes : Water, Soil, Air • Improve microbiological water quality, reduce diarrhea morbidity and mortality associated with waterborne disease • Standards for water quality – EPA – World Health Organization (WHO) • Total and fecal coliforms

Environmental Monitoring of Pathogenic Microbes : Water, Soil, Air Methods to measure water quality – Accurate and reproducible – Rapid – Relatively simple techniques, applicable to most laboratories – Common reagents, inexpensive

Environmental Monitoring of Pathogenic Microbes : Water, Soil, Air Detection of infectious agents in water – Many are difficult to detect/quantify • May require expensive equipment • Complex techniques – specialized reference laboratories – Newly recognized agents, methods are still being developed – Pathogen occurrence surveys and special studies

Environmental Monitoring of Pathogenic Microbes : Water, Soil, Air Detection of infectious agents in water – Laboratory investigations of disease outbreaks often never detect the etiologic agent • Contamination was temporary (e. g. problem was discovered and fixed before investigation) • Microbe died off or flushed away • Sensitivity/specificity of methods • Size of event

Environmental Monitoring of Pathogenic Microbes : Water, Soil, Air Detection of infectious agents in water – Microbial Indicator Organism • 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; surrogates for pathogens, especially bacterial • May not be reliable indicators of viruses and parasites

Environmental Monitoring of Pathogenic Microbes : Water, Soil, Air 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 "after growth" 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 are associated with risks of enteric illness in consumers (dose-response relationship)

Environmental Monitoring of Pathogenic Microbes : Water, Soil, Air 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 • Current microbial indicator criteria do not address those pathogens that are not associated with fecal contamination

Environmental Monitoring of Pathogenic Microbes : Water, Soil, Air Current and Candidate 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

Environmental Monitoring of Pathogenic Microbes : Water, Soil, Air 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

Environmental Monitoring of Pathogenic Microbes : Water, Soil, Air 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.

Cary residents told to boil water (Aug 18, 2006) http: //rdu. news 14. com/content/story_links/? Ar. ID=89457&Sec. ID=231 Town of Cary Press Release CARY, N. C. -- Officials told the approximately 100, 000 residents of the Wake County town of Cary to boil their water and they closed restaurants because fecal coliform was found Friday in a sample from one home. Results of the Town of Cary’s routine sampling and testing of its water supply has revealed the presence of E. coli on Coronado Way in the Coronado Village subdivision in central Cary. Water Contamination In Cary Costs Restaurants Millions August 22, 2006 http: //www. wral. com/apncnews/9718848/detail. html CARY, N. C. -- The restaurant shutdown ordered here over the weekend after E. coli was found in the water supply may have cost owners and employees some $6 million. Health officials ordered the town's 115, 000 residents To boil tap water and forced restaurants to close Friday night after the bacteria was detected.

Cary has 'weird' water mix-up News and Observer July 25 2007 "In a place like Cary, it never even occurred to me that this might even be a possibility, " Vinay Jain said Tuesday as Cary workers walked through his house testing taps. "This gives the impression of a Third World country. At least in India, we knew the water was bad, and we boiled it. " Cary Families' Faucets Delivered Treated Wastewater www. wral. com July 25 2007 N. C. family drinks lawn water for 5 months www. sciencedaily. com July 26 2007

Environmental Monitoring of Pathogenic Microbes : Water, Soil, Air Sources of drinking water • Surface water – Widely used as a supply for municipal DW – Need to protect from sources of contamination (land run -off, wildlife, recreational activities) • Ground water – Comprises 95% of water serving rural populations in US (>100 million people) – Assumed that soil will filter out most microbes – Rarely are private wells treated, also public H 2 O supply

Environmental Monitoring of Pathogenic Microbes : Water, Soil, Air • Traditionally, more than half waterborne disease outbreaks – groundwater responsible – From 1997 -98 15/17 (88%) reported outbreaks groundwater responsible – Most common pathogens identified = Shigella spp. and Hepatitis A virus – 2/3 of the time no etiologic agent identified

Environmental Transmission of Pathogenic Microbes : Water, Soil, Air • Soil microbial communities – Complex set of natural communities – 10, 000 species per gram of soil • Traditionally soil microbiology has focused on metabolic activities of microbes (e. g. biogeochemical cycles – nitrogen fixation) • Concern when pathogens on/in soil reach surface/ground waters or are disturbed (transmitted via air)

Environmental Transmission of Pathogenic Microbes : Water, Soil, Air • Sources of pathogenic soil microbes – Domestic drainage/septic systems – Land applied municipal sewage – Land applied agricultural waste – Landfills • Disposable diapers and animal waste– untreated waste penetrating subsurface – Naturally occurring

Environmental Transmission of Pathogenic Microbes : Water, Soil, Air • Although most of us don’t routinely ingest soil… – Infiltrated ground water – Surface of raw fruits & vegetables • Sampling – Surface soils – Subsurface soils • Horizontal and vertical variations • Perturbation of site, contamination • Specialized technologies for drilling and coring – Cost and expertise

Environmental Transmission of Pathogenic Microbes : Water, Soil, Air Survival and persistence of soil microbes • Some things to consider … – Soil type • Texture: sand>silt>clay • Moisture content: below 10% is biocidal – Adsorption to soil (esp. viruses) – Migration of microbes thru soil layers • Type and species of microbe (physiological & morphological characteristics) – Smaller microbes penetrate soil better – Virus>bacteria>protozoa

Environmental Transmission of Pathogenic Microbes : Water, Soil, Air Ground water recharge • Lack of water in arid SW US has prompted actions such as the land application or injection of treated wastewater to recharge subsurface aquifers • Movement of viruses (small size=greatest potential to be transported) thru soil mostly studied – In one study, indigenous enteroviruses were found in 9 m deep well, 14 m from recharge basin – Movement of larger microbes (bacteria and protozoans) theoretically less

Environmental Transmission of Pathogenic Microbes : Water, Soil, Airborne transmission • Bioaerosol – – “collection of airborne biological particles” – Droplets or particles 0. 5 to 30 μm diameter – Composition will vary with source & environmental conditions • Airplane

Environmental Transmission of Pathogenic Microbes : Water, Soil, Air Sources: any object that can produce droplets or aerosols – Humans and other animals (cough, sneezes) – Mechanical ventilation system – Fresh and marine surface waters, showers, whirlpool baths, toilets • Splash/wave action : microbes enclosed within droplet – Soil, plants • associated with particles, dust; act as “raft” • spores – US postal letters – mail-borne attack Oct. 2001

Environmental Transmission of Pathogenic Microbes : Water, Soil, Air Type of microbes found in bioaerosols: – Viruses, bacteria, fungi (spores & hyphae) – Generally protozoans are too large to remain airborne

Some Examples of Bioaerosols Living Source Examples Microorganisms (microbes): • Bacteria Legionella, Anthrax, endotoxins • Fungi Histoplasma, Cyptococcus, Pencillium, Aspergillus, Stachybotrys aflatoxins, • Protozoa Naegleria, Acanthamoeba • Viruses Rhinoviruses (colds), Influenza (flu), Coronaviruses (SARS), Hantavirus • Algae Chlorococus • Green plants Ambrosia (ragweed) pollen • Arthropods Dermatophagoides (dust mites)

Environmental Transmission of Pathogenic Microbes : Water, Soil, Airborne Microbes and their Reservoirs – Bacteria Legionella pneumophila • Reservoirs and amplifiers: – Hot water systems, circulating water ventilation systems (cooling towers), plumbing (e. g. , shower heads), hot tubs, whirlpools, produce fresheners • Legionnaire's disease: – A bacterial pneumonia that affects the lungs and may also affect the stomach and intestines, kidneys, and central nervous system – Frequently requires hospitalization

Environmental Transmission of Pathogenic Microbes : Water, Soil, Airborne Microbes and their Reservoirs – Bacteria Bacillus anthracis • Reservoirs and amplifiers: – Herbivores (e. g. , cattle, sheep, goats ) may become infected by ingesting spores while grazing in areas of high soil contamination – Anthrax can be found globally – Endemic to the parts of US (Dakotas, OK, TX) – Spores are extremely resistant, 50 years or more in soil – Animal carcass – vegetative cells will sporolate when exposed to air – Person-person spread unlikely – 2005: South Dakota: 11 counties: 39 outbreaks, 330 head; North Dakota: 13 counties, 86 cases • Anthrax: – Cutaneous: skin lesions from contact with spores or contaminated meat – Gastrointestinal: ingestion of spores or contaminated foods – Inhalation: often fatal, especially with inhalation of weapons-grade spores, symptoms resemble common cold, severe breathing problems, shock

Inhalation Anthrax Associated with Dried Animal Hides --- Pennsylvania and New York City, 2006 (Feb) March 17, 2006 / 55(10); 280 -282 • This report describes the first case of naturally acquired inhalation anthrax in the United States since 1976 • The patient made traditional African drums by using hard-dried animal hides (e. g. , air-dried until brittle enough to crack) obtained in NYC from importers who primarily sold African goat and cow hides. • Making the drums involved soaking hides for 1 hour in water and then scraping hair from the hides with a razor, which reportedly generated a large amount of aerosolized dust in the patient's workspace as the hides dried. • The man did not wear any personal protective equipment (e. g. , mask or gloves) while working.

Cutaneous Anthrax Associated with Dried Animal Hides (Sept 2007) • Two family members in Danbury, CT; on antibiotics and recovering • Goat and cattle hides imported from Africa used in drum making • Wore masks while working • Traffic rerouted around location; FBI, EPA, and other state officials notified • Neighbors evacuated • Samples taken from house, shed and soil • Positive samples from shed, door to shed, and rear entrance of home

Environmental Transmission of Pathogenic Microbes : Water, Soil, Air • Biohazard Detection System (BDS) – Combined automated air sampling w/internal automated testing system – Sampling interval 1. 5 hrs, 30 min analysis – Currently only set-up for B. anthracis spores – Used across the US in USPS PDC • Bio. Watch Program – – – Air monitors set up since 2003; >30 metro areas Goal: detect w/in 36 hrs release of anthrax, sm pox, plague (20) ~10 sensors per city, tested once a day 15 positives Not intended to prevent attack, hundreds of thousands of victims, instead start mass treatment

Environmental Transmission of Pathogenic Microbes : Water, Soil, Airborne Microbes and their Reservoirs – Viruses Coronaviruses (SARS) • Reservoirs and amplifiers: – First reported in Asia 2003, global outbreak-few months spread to two dozen countries – Person-person spread – respiratory droplets travel short distances (~ 3 ft) – Knowledge is still evolving • Morbidity/Mortality: – Flu-like symptoms, most develop pneumonia – 8, 437 people worldwide w/ 813 deaths – US: 192 cases, none died, very little transmission among close contacts and generally did not spread thru community!!? ?

Environmental Transmission of Pathogenic Microbes : Water, Soil, Airborne Microbes and their Reservoirs – Viruses Hantaviruses • Reservoirs and amplifiers: – Wild rodents - pass it in their droppings, urine, or saliva. The common house mouse does not carry hantavirus. – Human exposure - touch rodent urine, droppings, or places where these animals have nested. Most exposed (by inhalation) when sweeping areas with dried droppings or urine • Hantavirus pulmonary syndrome: – Flu-like symptoms, most develop cough and shortness of breath – Person-to-person spread unlikely – Around in US since 1950 s, took outbreak in “four corners” area of US to be recognized

Environmental Transmission of Pathogenic Microbes : Water, Soil, Airborne Microbes and their Reservoirs – Fungi Cryptococcus neoformans • Reservoirs and amplifiers: – Fungal Pathogen – Isolated from the soil worldwide, usually in association with bird droppings – Inhalation of airborne cells and/or spores • Cryptococcosis: – Initial pulmonary infection - usually asymptomatic – Disseminated infection, especially meningoencephalitis – one of the most common life-threatening fungal infections in AIDS patients – In the United States, 85% of cases occur in HIV-infected persons