1-some type of microorganism
2-Conditions for Food Borne Illness
3- overview
4-Causes of Food-Borne Diseases
5-food-borne infection
6-food-borne intoxication
7- major food-borne infections
8-Toxin
9-Detection of food-borne pathogens
10-preventions
3. Beneficial microorganism may be used in
the process of making new foods, cheese is
made with microorganisms which convert
the milk sugar to an acid.
Spoilage microorganisms cause load to spoil and are not harmful
to humans. A spoilage microorganisms is responsible for souring
milk.
Pathogenic microorganisms are disease-causing microorganisms.
The living microorganism or a toxin(microbial metabolic product
or waste products) must be consumed to cause symptoms
associated with specific pathogenic microorganisms.
4. The microorganism or its toxin must be present in food.
The food must be suitable for microorganisms to grow.
The temperature must be suitable for microorganisms to
grow
Enough time must be given for the microorganism to
grow(and to produce toxin).
The food must be eaten.
5. • WHAT IS FOODBORNE ILLNESS?
Foodborne disease (also referred to as foodborne illness or food poisoning) is any illness that results
from the consumption of contaminated food, contaminated with pathogenic bacteria, viruses, or
parasites.
• HOW IS IT CAUSED?
Many outbreaks and individual cases of foodborne illness result from consuming the two most common types
of foodborne pathogens:
Bacteria, like Salmonella, Listeria, Campylobacter , Shiga toxin-producing Escherichia coli
Viruses, such as norovirus or hepatitis A.
• WHO IS AT RISK?
Anyone can get a foodborne illness. But, some people have a higher risk, such as pregnant women, young
children, older people, and those with weak immune systems.
• WHAT ARE THE SYMPTOMS?
Symptoms range from relatively mild discomfort to very serious, life-threatening illness(flu-like symptoms
such as nausea, vomiting, diarrhea, or fever).
• HOW MANY FOODBORNE ILLNESSES ARE THERE IN THE US?
The Centers for Disease Control and Prevention (CDC) estimates that there are about 48 million cases of
foodborne illness every year
6. Bacteria
Salmonella, Campylobacter, E.coli, Vibrio cholerae, Listeria,
Staphylococcus, Clostridium perfringes and botulinum, Bacillus cereus
Virus
Norovirus, Rotavirus, Hepatitis A and E virus.
Parasites
Entamoeba Histolytica, Giardia lamblia, Taenia solium.
Toxins Mycotoxins, enterotoxin, cytotoxins, algal toxins, neurotoxins
Chemicals • Pesticides, Polychlorinated Biphenyls(PCBs),
• Heavy metals(lead, cadbium, mercury), Nitrites
7.
8. Food poisonings can be the result of either chemical poisonings or
the ingestion of a toxicant (intoxications).
There are two primary types of food-related diseases:
1. Food-borne infections - Direct involvement of microorganism.
2. Food intoxications- Indirect involvement of microorganisms or in
some cases microorganisms are not involved.
9. A food-borne infection involves the ingestion of the pathogen, followed by
growth in the host, including tissue invasion and/or the release of toxins.
Live organism must be consumed.
Examples –
• Salmonellosis caused by enterotoxin and cytotoxin of Salmonella spp.
• Clostridium perfringens illness by enterotoxin of C.perfringens.
• Bacillus cereus gastroenteritis: exoenterotoxin
• E.coli infection- some invasive and enterotoxigenic
Incubation period- Hours to days
Symptoms- Diarrohea, nausea, vomiting,abdominal pain and/or fever
Transmission- can spread from person to person via faeco-oral route.
Factors for food contaminations- inadequate cooking, cross
contamination, poor personal hygiene
10. Major Food-Borne Infections
Disease Organism Incubation
-Period
Symptoms Food
Involved
Control
Measures
Clostridium perfrinegens
gastroenteritis
C.Perfringens (Gram(+)ve, nonmotile,
aerobic)
8-24 hrs. Abdominal pain,
diarrhea, and gas,
fever, nausea.
Meat products,
especially poultry
Adequate and rapid
cooling of cooked
meats and food;
reheating of leftover
foods and good
personal hygiene
Enteropathogenic E.coli
infections
E. coli both enterotoxigenic and invasive
strains
8-44 hrs. Fever, chills,
headache, abdominal
cramp, watery
diarrhea ,
dehydration
Undercooked ground
beef, raw milk
Chills foods rapidly in
small quantities,
practice personal
hygiene
Salmonellosis S. enterica serovars, Typhimurium and
Enteritidis
8–48 hr
Enterotoxin and
cytotoxins
Fever, headache,
vomiting,
dehydration,
abdominal pain
Meats, poultry, fish,
eggs, dairy
Destruction of
microorganism in
food by heat;
prevention of
salmonella in foods
by adequate
refrigerations.
Vibrio parahaemolyticus
gastroenteritis
V. parahaemolyticus 16–48 hr Nausea, vomiting,
chills, mild fever,
headache
Seafood, shellfish Cooks foods
thoroughly, prevent
cross contamination
from saltwater fish.
11. Food borne intoxications is caused by ingesting food containing
toxins formed by bacteria which resulted from the bacterial
growth in the food item.
Sources of toxins are bacteria and fungi, some sea foods itself have a
toxin.
Examples-
• Staphylococcal food intoxication caused by Staphylococcus aureus
• Clostridial food intoxications caused by Clostridium botulinum
Incubation period- minutes to hours
Symptoms- vomiting, nausea, diarrhea, weakness, numbness, and
motor dysfunction.
Transmission- not communicable
Factors for food contamination- inadequate cooking and improper
holding temperatures
12. Staphylococcal
intoxications
Caused by ingestion of the enterotoxin formed in food during
growth of certain strains of Staphylococcus aureus.
Food intoxication is caused by Type A ( S.aureus produces six
serologically distinct enterotoxin A,B,C1,C2,D,E).
Temperature- 04-46o C.
Minimal pH for growth is:
4.8- under aerobic conditions
5.5- anaerobic conditions
Water activity
0.86- aerobic
0.90- anaerobic
Incubation period- 2-4 hrs.
Symptoms- salivation, nausea, vomiting ,chills , sweating ,
abdominal cramp.
Food involved- custard cream-filled bakery, ham and poultry.
13. Botulism
Botulism is a disease caused by the ingestion of food containing the
neurotoxin produced by Clostridium botulinum.
Seven types of C.botulinum (A,B,C,D,E,F,G) are distinguished on the
basis of the serological specificity of their toxins.
Type A is most potent.
A pH nears neutrality favors growth. pH 4.5 or lower prevent toxin
production in most foods.
Max. growth temperature- 48o C.
Min. temperature for growth- 3.3o C.
Incubation period- 12-36 hrs.
Symptoms- nausea, vomiting, fatigue, dizziness, headache.
Food involved- preserved meat and fish, inadequately home canned
foods.
14. • Intoxications- diseases that results from a specific toxin.
• Toxin- is a substance, such as a metabolic product of the organism that
alters the normal metabolism of host cells.
• Toxemia – conditions caused by toxins that entered the blood of the
host.
Organism Toxin
Bacteria Neurotoxin- C.botulinum
Enterotoxin- S.aureus
Fungi Afalatoxin- A.flavus
Patulin- A.clavatus
Algae Okadaic acid
Natural toxins Histamine, glycoalcoloids
16. Preventions
Key recommendations for food safety
Keep clean
Separate raw and cooked food
Cook food thoroughly
Keep food at safe temperatures
Use safe water and raw materials