waterborne infectious diseases david l. taylor, phd infection preventionist dept of clinical...
Post on 31-Dec-2015
217 Views
Preview:
TRANSCRIPT
WATERBORNE INFECTIOUS DISEASES
David L. Taylor, PhDInfection Preventionist
Dept of Clinical EpidemiologyThe Ohio State University Medical Center
Discussion:
• Sources and microbial etiologies of waterborne infections• Interesting outbreak associated with contaminated water
WHO GETS INFECTED?
• All of us• Normal, healthy people• Adults• Kids – worldwide (2 million deaths)• Sick people
FROM WHERE?
• Normal water microbes• Fecal contamination of water• Animals• Wild animals• Farm animals• People
• Feces• Vomitus• Hands
WHAT ARE THE WATER SOURCES?
• Surface water• Well water• Recreational water
- lakes, pools, hot tubs, etc• Cruises• Healthcare facilities
- Droplets, Rinse water, Hydrotherapy, Birthing, Warming baths, Holy water
WHAT MICROBES?(# OF CASES, OHIO, 2002)
• Bacteria ParasitesSalmonella (1400) Giardia (1000)Escherichia coli (200)
Cryptosporidium(120)Shigella (600) Viruses
Campylobacter(1300) NorovirusLegionella (26) Hepatitis A ((1400)Mycobacterium
COMMON INFECTIONS & CHARACTERISTICS
Incub SickSalmonella 12-48 hr 4-7 dE. coli 12-48 hr 2-7 dShigella 12-96 hr 2-7 dCampylobacter 2-5 d 7 dGiardia 1-2 wks 2-6 wksNorovirus 12-48 hr 12-24 hr
HOW ARE INFECTIONS TREATED?
• Salmonella – not generally treated – prolongs “carrier state”• E coli – generally not treated• Shigella – frequently treated – questioned: develop resistance?• Campylobacter – not treatedGiardia – treated• Norovirus – no antiviral therapy available
HOW ARE THE INFECTIONS PREVENTED?
• Don’t drink contaminated water• Treat water• Boil water• Point-of-use filter• Bleach• Hand hygiene • Prevent contamination of water
OUTBREAKSDrinking Water, ’91-’92
• 17 states - 34 outbreaks - 17,464 people• 11 outbreaks with identified agent
7 of 11, Giardia or CryptosporidiumSurface-influenced groundwater
Shigella & Hep A – contaminated well water• 68% no etiology; 1 outbreak of 9,847 people• 76% involved well water
OUTBREAKSRecreational Water, ’91-’92
• 21 states - 39 outbreaks - 1,825 people• 12 outbreaks - Pseudomonas dermatitis - hot tubs• 11 outbreaks – swimming
6 Giardia or Cryptosporidium1 E coli enterotoxigenicAmoebic meningoencephalitis - 6 deaths
SOUTH BASS ISLAND OUTBREAK – an interesting
outbreak here in Ohio
• History of travel to So Bass Island• History of gastroenteritis• ODH notified August 3, 2004• May 30 – Sept 10 (3 ½ months)• Sporadic cases June, peaked in July & Aug, decreased after August 19• Over 1450 people
SOUTH BASS ISLAND OUTBREAK (2)
• Case-control study• Questionnaires:
Initially generalThen more specific - water
• Sources of water:Municipal water & well waterTreated water from Lake Erie to Put-in-
BayWells on western side of islandWells supplement municipal water
SOUTH BASS ISLAND OUTBREAK (3)
• Cases “more likely to drink tap water than were controls.”• Difficult to tell where water came from
Wells supplement municipal water at various times
Drank from different sites (business, home, motel, etc)
Where did they drink when they acquired the microbe?
SOUTH BASS ISLAND OUTBREAK (4)
• Confirmed positive specimens (of 155):15 Campylobacter9 Norovirus1 Salmonella1 Giardia
• Difficult to get specimensCalifornia, CanadaShort illness, better before getting
specimen
SOUTH BASS ISLAND OUTBREAK (5)
• Cases peaked at beginning of week (Mon, Tues)• Only 155 specimens• Investigated by CDC, state and local (Ottawa County) health departments, EPA• 42 wells tested - 32 positive for “coliforms”
SOUTH BASS ISLAND OUTBREAK (6)
• EPA Orders (issued 9/3/04)- “No Use Orders” – for drinking, preparing food, washing dishes, hand washing,
showering, or oral care- Facilities with no results returned –
inspect water treatment equipment & test more frequently
- To Put-in-Bay – ensure compliance with drinking water regulations and inspect
every service for presence of auxiliary wells
SOUTH BASS ISLAND OUTBREAK (8)
• Safe Drinking Water Guidelines- With wells – consider drinking bottled
water or water that has been at a rolling boil for at least one minute
- Use disinfected, bottled or boiled water for drinking, cooking, making prepared drinks, or brushing your teeth
- Practice thorough & frequent hand washing
top related