Environmental Transmission of Pathogenic Microbes –

why they are, where they are, when they are

Dr. Julie Ann Kase Public Health Scientist – Bioterrorism and Emerging Pathogens Unit NC State Laboratory of Public Health [email protected]

• • • • • •

1976 Legionnaires' disease

– Outbreak of pneumonia occurred among persons attending a convention of the American Legion in Philadelphia – ~ 8,000 to 18,000 cases in the US each year; 5% to 30% die

1981 AIDS

– report in MMWR of 5 CA men with severe immunodeficency (1983 HIV recovered from lymph node)

1993 Cryptosporidiosis

– 400,000 people sick and killed more than 100 – worst waterborne disease outbreak in the United States

1995 Ebola Hemorrhagic Fever

– Ebola Virus initial recognition in 1976 – Occurred in Kikwit and surrounding area – 315 cases 81% death of cases

2002 (November) Severe acute respiratory syndrome (SARS)

– Viral respiratory illness that was recognized as a global threat in March 2003 – first appearing in Southern China in November – November 2002 - July 2003, a total of 8,098 people worldwide became sick; 774 died – By late July 2003, no new cases, and WHO declared the global outbreak to be over

Late 2003 and Early 2004 Avian influenza

– Outbreaks of influenza H5N1 occurred among poultry in eight countries in Asia (Cambodia, China, Indonesia, Japan, Laos, South Korea, Thailand, and Vietnam) – By March 2004, the outbreak was reported to be under control until late June 2004 – Human infections (H5N1) have been reported in Thailand, Vietnam and Cambodia

E. coli O157:H7 Outbreak Case Counts by State

(As of October 6, 2006)

www.cdc.gov

Cases infected with the outbreak strain of

Salmonella

Saintpaul, United States, by state, as of August 25, 2008 9pm EDT

www.cdc.gov

Seek and Ye Shall Find

• Environmental Transmission

– Presence • Cover our planet – Several 100m deep in glacial ice sheets – Deep-ocean thermal vents – Survival and transport • Media – Water – Soil – Air • Natural fate + influence of man’s actions

Microbial

Survival

in the Environment

• Pathogen survival Differs widely among microbes: – Bacteria: • Spores survive better than vegetative cell – Viruses: • non-enveloped viruses survive better than enveloped viruses under most environmental conditions – Envelopes are relatively fragile compared to outer capsids (protein coats) – Parasites: • protozoan (oo)cysts and spores and helminth ova survive better than active life stages of these parasites or than those with no resting or special environmental forms – Fungi: • spores survive better than other forms

Environmental

Factors

Influencing Survival or Proliferation of Infectious Agents

• Temperature – Greater inactivation/death rates at higher temps – Environmental temperatures influence pathogen spread by insect vectors • pH – Extreme pH inactivates microbes – Important exceptions: enteric pathogens survive pH 3.0 • Moisture content – Drying or low moisture inactivates /kills some microbes – Ex. Preserving food by desiccation • Sunlight (UV) – Nucleic acids absorb the UV energy and is damaged

Environmental

Factors

Influencing Survival or Proliferation of Infectious Agents

• Pressure (atmospheric & hydrostatic) – Typical atmospheric pressure – Use of high hydrostatic pressure in shellfish • Weather – Microbes levels may increase or decrease – Warmer weather increases some microbes (ex. Vibrio bacteria in NC coastal waters during warmer months) and vectors, like mosquitoes – Wet weather carries microbes also resuspension in water resources • Chemicals & nutrients – Levels influence microbe survival – Ex. Lack of nutrients (e.g. carbon, nitrogen) will limit proliferation • Biological factors – Predation, vectors, reservoirs (animals), microbe species/type

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air • Microbes can be found anywhere in which water is maintained in a liquid state • Human illness associated with water – usually acute in nature but some have chronic sequelae (e.g. stomach cancer (

Helicobacter pylori

), myocarditis & diabetes (coxsackieviruses )) • Highly effective means of introducing an infectious microbe to a large population – Person-to-person not efficient in reaching a large population

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air Reservoirs for pathogenic microbes found in water:

humans, animals, environment

– Source tracking – Human sources – important contributor of pathogens in water • Recreational activities (e.g. water theme parks) • Domestic wastewater – Discharge of wastewater into surface waters – Aquifer contamination

Infectious Disease Water Transmission Model

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air

Microbial agents associated with waterborne diseases

– Enteric, non-enteric,and aquatic bacteria – Enteric viruses – Enteric protozoa

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air Enteric bacteria – Shigellosis:

Shigella spp.

• occur around the world, with most victims being children in developing countries • 300,000 cases of shigellosis are reported in the United States (not all confirmed) (classical bacillary dysentery) •

Shigella dysenteriae

type 1 – deadly epidemics in dev. world • Spread can be via vector, food, water, and fomites – Cholera:

Vibrio cholerae

serogroup O1 or O139 (1992) that produces toxin • Endemic poverty, summer rains, poor health & living conditions • 56 countries, 101,383 cases (2345 deaths) in 2004 • Africa - 94% cases in 2004 • No major outbreaks of this disease have occurred in the United States since 1911 • Easily treatable – Infectious dose variable: 10 - 500 orgs http://www.cfsan.fda.gov

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air

Aeromonas hydrophila

• Commonly found in water but recently implicated as a cause of GI illness, also wound infection • Potential to grow in water distribution systems, especially in biofilms, where it may be resistant to chlorination • EPA list (candidate contaminant list) for drinking water

Legionella pneumophila

• • Ubiquitous in water, aerosol transmission Proliferate at high temperatures (hot water systems, cooling towers and evaporative condensers) • Etiologic agent of Legionnaires’disease, Pontiac fever • • •

Leptospira spp.

Species not enteric or aquatic - Urine from dom. & wild animals Outbreak during Eco-Challenge - grueling 2-week contest in late Aug and early Sept [2000] island of Borneo http://www.youtube.com/watch?v=RMIFu5qWjSU&feature=related

Leptospirosis

• Reports of outbreaks occurring following flooding, tropical storms, hurricanes – all can increase the exposure to contaminated water • Asymptomatic, high fever, severe headache, muscle aches • LA- found in cattle, skunks, rodents • Most common in tropic climates • Recent outbreaks of leptospirosis in the US have occurred in Illinois and Florida (CDC, unpublished data), while leptospirosis is endemic to Hawaii • According to the Centers for Disease Control and Prevention (CDC), between 100 and 200 cases of leptospirosis are reported in the United States each year as of the early 2000s. http://www.cdc.gov/ncidod/dbmd/diseaseinfo/leptospirosis_t.htm

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air Enteric viruses – Generally more persistent than enteric bacteria but can not multiply in environment – Survival influenced by physical, chemical, and microbial factors as well as virus type • Non-enveloped viruses most persistent – protein coat offers stability and resistant barrier to stressors • Majority of enteric viruses are non-enveloped – Require more sophisticated detection methods • Tissue cultivation, electron microscopy, molecular techniques (e.g. PCR, nucleic acid hybridization) • Limit microbe ID from clinical & environmental samples • Distinguish between infectious/non-infectious - MAYBE

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air Implicated in majority of AGI outbreaks in US based upon clinical & epidemiological evidence • •

Rotavirus

– – the virus is stable in the environment, transmission can occur through ingestion of contaminated water, global problem – Rotavirus is the most common cause of severe diarrhea among children, resulting in the hospitalization of approximately 55,000 children each year in the United States and the death of over 600,000 children annually worldwide

Norovirus

– – Among the 232 outbreaks of illness reported to CDC from July 1997 to June 2000, 3% were waterborne; in 23% of outbreaks, the cause of transmission was not determined – Waterborne outbreaks of norovirus disease in community settings have often been caused by sewage contamination of wells and recreational water.

– Infectious dose: typically low, maybe 1 to 10 infectious units – Developing countries: Hepatitis A virus, Hepatitis E virus

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air • Proposed EPA drinking water contaminant list The Safe Drinking Water Act directs that periodically publish a CCL • 2003 - regulatory determinations for nine contaminants from the first CCL (60 contaminants in March 1998) • Summer of 2005 - second cycle of preliminary regulatory determinations - continue research on the list of contaminants on the first CCL – – – –

Adenoviruses Helicobacter pylori Noroviruses Aeromonas hydrophila Coxsackieviruses Cyanobacteria Echoviruses

• February 2008 = Draft CCL 3 efforts to expand and strengthen the CCL listing process –

Caliciviruses

– –

Campylobacter jejuni Entamoeba histolytica

– – – – –

Escherichia coli (0157) Helicobacter pylori Hepatitis A virus Legionella pneumophila Naegleria fowleri

– – –

Salmonella enterica Shigella sonnei Vibrio cholerae

“Payment Intervention Studies”: References •

Payment P., et al, (1991).

A Randomized Trial to Evaluate the Risk of Gastrointestinal Disease due to Consumption of Drinking Water Meeting Current Microbiological Standards. American Journal of Public Health 81 (6) 703-708.

•

Payment P., et al (1997).

A prospective epidemiological study of gastrointestinal health effects due to the consumption of drinking water. International Journal of Environmental Health Research. 7(1). 1997. 5-31

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air

Payment et al. intervention studies

Wanted to know risk of GI illness associated w/consumption of municipal drinking H 2 O – Municipal H 2 O source = river polluted with human sewage – 1 st study: 606 households; ~half had RO filters, others no intervention; 15mo • 35% higher rate of GI symptoms households w/o intervention; symptoms & serologic evidence pointed to enteric viruses – 2 nd study: 1400 households; 3 groups w/tap H 2 O, 1 group purified bottle H 2 O; 16 mo • ~20% more GI illness in tap H 2 O consumers

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air Enteric protozoa – Recently recognized as water borne pathogens – Thick-walled protozoan cysts and oocysts are environmentally resistant – Recovery and detection technically challenging • Filtering liters of water • Immunofluorescence microscopy • May not distinguish between nonviable/viable orgs – Infectious dose is low •

C. parvum

~ 100 oocysts

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air Enteric protozoa (cont.) – Ex.

Cryptosporidium, Giardia

• Size: C

ryptosporidium

oocysts (4-6 µm)

Giardia

cysts (7-14 µm) • Animal reservoirs • Size limits movement thru soil, thus surface waters contamination mostly (esp. unfiltered) • Greater than half of 300 surface water supplies in US contained C

ryptosporidium

oocysts – Ex.

Toxoplasma gondii

– Matures only inside cats and spreads through their feces – Lethal parasite that has infected or killed hundreds of California sea otters – Parasite can concentrate inside clams and other bivalves, favorite of otters – Flushable cat litter runoff from land, affecting the ecosystem, including the clams that otters eat

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air • • • Other aquatic microbes • Cyanobacteria – algal blooms, dermatitis

Naegleria fowleri

– meningoencephalitis, usually fatal – small, free-living amoeba – occ. infects humans & other mammals

N. fowleri

can invade the CNS via the nose & nasal tissues – 2003 case in North Carolina – In August 2008, a 9-year-old boy was killed after having been exposed to the amoeba while swimming several times in Lake Elsinore in CA

Acanthamoeba species

– subcutaneous abscesses, conjunctivitis – Contact lens wearers, EPA published warning:

Acanthamoeba Guidance Document EPA-822-B-04-001

– Amoebae invades the cornea of the eye – EPA determined not to regulate because “regulation would not present a meaningful opportunity for health risk reduction”

Schistosoma species

– dermatitis, swimmer’s itch – Debilitating (liver and intestinal damage) illness that results from infection of the blood with a parasitic flatworm (schistosome) – Found in Asia, Africa, and South America, especially in areas with water that is contaminated with fresh water snails, which contain the parasite

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air Categories of water-related infectious hazards – Waterborne – Water contact – Water related – Water washed

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air

Waterborne

– Physical contact w/microbially contaminated H 2 O – Bathing, recreational activities, ingesting water (also ice) – Example: cholera

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air Water Contact – Infections caused by aquatic organisms • Pathogenic microorganisms or macroorganisms (worms) • Naturally spend part of life cycle in aquatic envr or within a host that resides in water – Ingestion or immersion in water – Example: Schistosomiasis

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air Water Related – Disease as a consequence of being bitten by an invertebrate vector whose life cycle requires access to H 2 O – Influences of season, rain events (monsoon, flooding) – Example: Malaria (parasite) and yellow fever, west nile infection (viruses)

Environmental

Transmission

of Pathogenic Microbes :

Water

,

Soil, Air Water Washed – Infections associated with inadequate hygiene – Eliminate hazard by using microbe-free water for cleaning of eating and cooking utensils, plates, self, etc.

– Example: Shigellosis

Environmental Transmission of Pathogenic Microbes – Part 2

Dr. Julie Ann Kase Public Health Scientist – Bioterrorism and Emerging Pathogens Unit NC State Laboratory of Public Health [email protected]

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 specific 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

especially bacterial for pathogens, • 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

Contamination Indicators of Fecal • 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

Environmental

Monitoring

of Pathogenic Microbes :

Water

,

Soil, Air Microbial Indicators of Fecal Contamination and Treatment Efficacy for Enteric

Protozoan

Pathogens •

Clostridium perfringens spores

protozoan parasites may be useful indicators of enteric – Plentiful in feces, raw sewage, treated effluents and receiving waters and soils –

Spores of aerobic bacilli

water treatment efficacy (

Bacillus

spp.) may be useful indicators of – 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

OF WATER INDICATORS OF FECAL CONTAMINATION

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.news14.com/content/story_links/?ArID=89457&SecID=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

CARY, N.C. --

http://www.wral.com/apncnews/9718848/detail.html

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 – EPA estimates: 185,000 viral illnesses/yr from ground water

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 thru soil mostly studied – Small size = greatest potential to be transported – In one study, enteroviruses were found in 9m deep well, 14m from recharge basin

Environmental

Transmission

of Pathogenic Microbes :

Water, Soil,

Air

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

• Bacteria • Fungi • Protozoa • Viruses • Algae • Green plants • Arthropods • Mammals

Legionella, Anthrax, endotoxins Histoplasma,Cyptococcus, Pencillium, Aspergillus, Stachybotrys aflatoxins, Naegleria, Acanthamoeba Rhinoviruses (colds), Influenza (flu), Coronaviruses (SARS), Hantavirus Chlorococus Ambrosia (ragweed) pollen Dermatophagoides (dust mites) Horse or cat dander

Environmental

Transmission

of Pathogenic Microbes :

Water, Soil,

Air

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 Aug 2008 – Elmira (NY) Housing Authority said they suspended the use of hot water in the senior housing complex. Tests revealed Legionella pneumophila in the hot water system

–

10 cases & health officials have been advising residents to take sponge baths instead of showers to avoid breathing in water vapor

Environmental

Transmission

of Pathogenic Microbes :

Water, Soil,

Air

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 • BioWatch 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,

Air

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 (~ 3ft) – 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,

Air

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 1950s, took outbreak in “four corners” area of US to be recognized – 15 Aug 2008: A policeman, 34, died at Yakima Valley Memorial Hospital Wa, barely 48 hours after suffering symptoms

Environmental

Transmission

of Pathogenic Microbes :

Water, Soil,

Air

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