Food Borne Diseases

1
Food Borne Diseases Food Microbiology

• Dr Karven J Cooray
• Consultant Microbiologist, M.R.I

2
Different types of microbes
3
Waterborne pathogens

• Viruses
• Rotavirus, Adenovirus, HAV, HEV, Poliovirus
• Bacterial
• Shigellosis, Vibrio cholarae, Enteric Fever,
• Leptospirosis, Legionellosis
• Parasitic
• Entamoeba histolitica
• Giaradia lambia

4
Foodborne Pathogens

• Bacteria
• Salmonella Staphylococcus
  aureus Clostridium perfringens Campylobacter
• Bacillus cereus Vibrio species
• Listeria monocytogenes Escherichia coli
  O157H7 Yersinia enterocolytica Clostridium
  botulinum
• Brucella
• Viruses
• Calicivirus Norwalk Norwalk-like viruses. 
• Parasites
• Fungi

5
Food Waterborne diseases Year 2002

• Disease Cases a Notified b Confirmed c
• Shigellosis 11335 9220 2923
• Enteric Fever 6786 2854 882
• Viral Hepatitis 5260 2847 1048
• Food Poisoning 4976 1045 185
• Leptospirosis 2748 950 355
• Cholera 157 NA NA
• Source
• a Indoor morbidity register IMR NA- Not
  available
• b Weekly epidemiological report
• c Annual Health Bulletin 2003

6
Diarrhoeal Pathogen Profile MRI 2004 Viruses
Parasites not included
7
Microbes Food

• Microorganisms are ubiquitous
• Air, water, soil, in and on animals, plant
  surfaces including food
• Every Food has its own micro flora
• Most of them are not pathogenic
• When given a chance they multiply in food
• Post harvest mishandling of vegetables ?
• Highly enriched food ? Spoilage, Decomposition

8
Factors affecting Microbial Quality of food

• Raw material quality and Storage
• Factory Layout
• Work Surfaces and cleanliness
• Water Quality
• Temperature and other Conditions applied in
  processing
• Personnel Hygiene
• Packaging
• Transport Storage
• Shelf life

9
Factors affecting Microbial Growth in food

• Nutrient Content
• pH
• aW Water Activity
• Oxidation Reduction Potential
• Growth of Growth Inhibitors
• Temperature

10
Pathogenic Microorganisms

• Some times food is contaminated with pathogens.
• Virus, Bacteria, Fungi, Parasites
• When consumed, likely to get food born disease.

11
Type of Samples in QC

• Final Product
• On line Sampling
• Raw Material

Auto florescence for Screening Aspergillus
12
Quality of milk Milk Products
13
Types of tests Pour Plate Method

• Aerobic Plate Count
• Yeasts Moulds Count
• Enterobactericae count

14
Indicator Organsims

• Coliform count
• E.coli count
• Faecal Streptococci
• Clostridium perfringens

15
Presumptive Coliform countMPN Method
16
E.coli count - MPN Method
17
Surface Spread Method Staphylococcus, Listeria,
B.cereus, C. Perfringens
18
SLS Specifications for Ice cream

• n c m M
• APC 5 2 50000 250000
• Coliforms 5 2 100 1000
• Salmonella 10 0 0 -
• n No of sample units to be tested
• C maximum allowable units of defective sample
  units
• m limit under which a count is acceptable for
  any sample unit
• M limit above which a count is unacceptable for
  any sample unit

19
Scale of Sampling Ice cream

• No of units No of units
• in the lot to be selected
• Up to 300 11
• 301 to 500 12
• 501 to 1200 13
• 1201 to 3000 15
• 3001 to 10000 18
• 10001 and above 21

20
Response to a food poisoning out break

• Chemical
• Microbiological
• Plant Products Poisons
• Animal products Poisons

21
Response to a food poisoning out break

• Point source out break - Common experience of
  food ingestion
• Notification Poor and delays
• By the time notified, food samples are
  unavailable for analysis
• Patient samples most important
• Laboratory facilities - MRI

22
Three groups of Health Personnel

• Need to communicate among each other
• Curative
• History
• Sample collection Transport
• Patient Management
• Notification
• Preventive Health Sector
• Collecting data Inward Community
• Data analysis
• incriminating food - Retrieve any food proved to
  be
• Mean Incubation period
• Signs symptoms
• Facilitate sample transportation for analysis
• Prevention of further episodes
• Food retrieval Health Education

23
Three groups of Health Personnel

• Need to communicate among each other
• Laboratory Sector Analysis of samples
• samples
• Patient, stools, vomitus
• Food Water
• Food preparation environment
• Identification of the pathogen
• Epidemiological typing

24
Clinical Features of Bacterial Food Poisoning
25
Clinical Features of Bacterial Food Poisoning
26
Clues to the agent

• Type of Food
• Signs Symptoms
• Mean Incubation period
• Occurrence of secondary cases
• Nawalk

27
Water Quality Data in Year 2007 at MRI
28
PREVENTING FOODBORNE ILLNESS

• Clean Wash hands and surface often. Bacteria can
  spread throughout the kitchen and get on to
  cutting boards, knives, sponges and counter tops.
  
• Wash hands in hot soapy water before preparing
  food and after using the bathroom, changing
  diapers and handling pets. For best results,
  consumers should use warm water to moisten their
  hands and then apply soap and rub their hands
  together for 20 seconds before rinsing
  thoroughly.

29
Clean .

• Wash cutting boards, knives, utensils and
  counter tops in hot soapy water after preparing
  each food item and before going on to the next
  one.
• Use plastic or other nonporous cutting boards.
  Cutting boards should be run through the
  dishwasher or washed often in hot soapy water
  after use.
• Consider using paper towels to clean up
  kitchen surfaces. Or, if using cloth towels,
  consumers should wash them often in the hot cycle
  of the washing machine.

30
Separate

• Dont cross-contaminate. Cross-contamination is
  how bacteria spread from one food product to
  another. This is especially true for raw meat,
  poultry and seafood. Keep these foods and their
  juices away from ready-to-eat foods.
• Separate raw meat, poultry and seafood from
  other food in the grocery cart.
• Store raw meat, poultry and seafood on the
  bottom shelf of the refrigerator so juices dont
  drip onto other foods.

31
Separate .

• If possible, use one cutting board for raw
  meat products and another for salads and other
  foods that are ready to be eaten.
• Always wash cutting boards, knives and other
  utensils with hot soapy water after they come in
  contact with raw meat, poultry and seafood. Then
  sanitize with 1 teaspoon liquid chlorine bleach
  per quart of water.
• Never place cooked food on a plate that
  previously held raw meat, poultry or seafood.

32
Cook

• Cook to proper temperatures. Foods are properly
  cooked when they are heated for a long enough
  time and at a high enough temperature to kill the
  harmful bacteria that causes foodborne illness.
• Use a meat thermometer, which measures the
  internal temperature of cooked meat and poultry,
  to make sure that the meat is cooked all the way
  through.
• Cook roasts and steaks to at least 145 ºF.
  Cook pork to 160 ºF and poultry to 165 ºF

33
Cook

• Cook ground beef, where bacteria can spread
  during grinding, to at least 160 ºF. Dont depend
  on color changes to indicate safety! Ground beef
  may turn brown before it has reached a
  temperature at which bacteria are destroyed.
  Information from the Centers for Disease Control
  and Prevention (CDC) links eating undercooked
  ground beef with a higher risk of illness.
• Cook eggs until the yolk and white are firm,
  not runny. Dont use recipes in which eggs remain
  raw or only partially cooked.

34
Cook

• Cook fish until it is opaque and flakes easily
  with a fork.
• Make sure there are no cold spots in food
  (where bacteria can survive) when cooking in a
  microwave oven. For best results, cover food,
  stir and rotate for even cooking. If there is no
  turntable, rotate the dish by hand once or twice
  during cooking.
• Bring sauces and gravy to a boil when
  reheating. Heat other leftovers thoroughly to 165
  ºF.

35
Chill

• Refrigerate promptly. Bacteria multiply rapidly
  between 40 ºF and 140 ºF. Refrigerate foods
  quickly because cold temperatures keep most
  harmful bacteria from growing and multiplying.
  Public health officials recommend setting the
  refrigerator at 34 to 38 ºF and the freezer unit
  at 0 ºF and occasionally checking these
  temperatures with an appliance thermometer

36
Chill.

• Refrigerate or freeze perishables, prepared
  food and leftovers within two hours.
• Never defrost (or marinate) food on the
  kitchen counter. Use the refrigerator, cold
  running water or the microwave.
• Divide large amounts of leftovers into small,
  shallow containers for quick cooling in the
  refrigerator.
• With poultry and other stuffed meats, remove
  the stuffing and refrigerate it in a separate
  container.
• Dont pack the refrigerator. Cool air must
  circulate to keep food safe.

37
Thank You !