Flashcards in Lecture 17: Waterborne and Foodborne Diseases Deck (31)
What are the characteristics of waterborne and foodborne diseases?
bacterial pathogens that cannot be eliminated
Reservoir is food/water and not transmitted from human to human
What kinds of epidemics can food/waterborne diseases cause?
common source epidemics
What is the single most important factor for public health?
Clean water w/ no iological/chemical contamination
What is monitored in maintaining water quality?
Chemicals, radioactive substances, microorganisms
What is GenX?
Industrial chemical used in teflon
produced by chemours (DuPont) companies
GenX is unregulated y EPA, what is the criteria for regulation?
1. Adverse effect on public
2. High risk to occur in public H2O
How are we studying GenX in Wilmington?
Cross sectional study w/ 400 residents
1. Blood and urine
2. Household drinking water
What are some water purification methods?
-effective + expensive
-effective + inexpensive
How do we monitor microorganisms when monitoring water?
Look for Fecal Coliforms
-bacteria present in intestines of humans
-indicator of water contamination not quality
What are the rules of the revised total coliform rule for monitoring water quality?
1. Sites representative of system
2. Collection occurs at regular time intervals
3. Number of collections depends on population size
4. Each positive result is retested
What are some waterborne diseases?
Drinking water outbreaks
-contaminated drinking water
Recreational water outbreaks
-contaminated pools and lakes
What is cholera?
pathogen - vibrio cholera
Is vibrio cholera Gram (+) or (-)? What is its reservoir?
reservoir - coastal + marine habitats
What is the pathogenesis of cholera?
caused by ingestion of contaminated water
-attached to wall of small intestine and produces cholera toxin
How is cholera diagnosed?
presence of V. cholera cells in feces
How is cholera prevented?
Vaccine for some strains
maintain adequate sewage treatment and safe drinking water
How is cholera treated?
fluid replacement and antibiotics
What is legionnaires disease?
-gram (+) or (-)
-pathogen: Legionella pneumophila
-reservoir: lakes and streams
What is the pathogenesis of legionairres disease?
airborne transmission and infection in lungs
-mild infection = pontiac fever
-severe infection = pneumonia
How is legionairres disease diagnosed?
cultures from body fluids
How is legionairres disases prevented and treated?
air conditioning maintenance and hyperchlorination
Treated with antibiotics
What is the first line of defense against foodborne diseases?
What are the major food categories?
1. perishable - fruit
2. semi-perishable - potatoes
3. nonperishable - flour
How do we reduce microbial growth on food?
1. Low temp - refrigeration
2. Low pH - pickling
3. Low water - drying
4. Low Oxygen - vacuum
What are chemical preservatives used for
increase shelf life and perceived quality of food
What are some other preservation methods for food?
High pressure processing
-high hydrostatic pressure kills microbes
-ionizing radiation kills microes
What is the difference between food poisoning and food infectIon?
-ingestion of food containing microbial toxins
-ingestion of food containing vialbe pathogens
-takes longer for symptoms to appear
What kinds of bacteria cause food poisoning?
-reservoir=meat, poultry, cream
-reservoir= raw meat
-improper garlic canning
What are some treatment and prevention of food poisoning?
supportive treatment (fluids)
sanitation in food production