Food Born Diseases

1. Prepared By
Dr. NABIL AL-HAJJ
Department of Therapeutic Nutrition
Science and Technology University,
Yemen, Aden
Food Born Diseases

2. FOOD BORNE DISEASES
➢ Food borne diseases is any diseases resulting from
the consumption of contaminated food, pathogenic
bacteria viruses or parasites that contaminate food,
as well as chemical or natural toxins such as
poisonous mushrooms.
How chemicals enter foods
➢ Accidental contamination by Heavy metals which come to the food from
food preparation tools, Pesticides, and radionuclides.
➢ Intentional addition e.g preservatives such as nitrite and sodium
nicotinate for color preservation and fungicides used for during storage.
➢ Zinc, copper surfaces, lead pipes, asbestos roofs.

3. Observations of FBD
✓ WHO estimates that one in teen people worldwide suffer from a food-
borne disease every year,
✓ Half million die from severe food and waterborne diarrhea ,related illness
✓ Most of these illnesses are due to microorganisms and chemical
contaminants, which may occur naturally or be introduced at some point
along the food chain.
✓ Campylobacter and Salmonella species account for over 90% of all
reported cases of bacteria related to food poisoning worldwide.
✓ As most cases of food borne disease are not reported, the true dimension
of the problem is unknown.
✓ Today food safety is one of WHO’s top eleven priorities

4. Food Borne infection
• It is an illness caused by bacteria present in food or other microbes which
infect the body after it is eaten.
Food Borne intoxication
• It is an illness caused by toxin present in food, including bacterially
produced exotoxins, which can happen even when the microbe that
produced the toxin is able to cause infection.
What is the difference between food infection and food intoxication?
• Foodborne infection is caused by the ingestion of food containing live bacteria
which grow and establish themselves in the human intestinal tract.
• Food borne intoxication is caused by ingesting food containing toxins formed by
bacteria which resulted from the bacterial growth in the food item.
Classification of Food Borne Disease

5. Con. Food borne infections
• Bacterial food borne infections include Cholera,
salmonellosis, typhoid fever, shigellosis, Escherichia coli
infection,
Campylobacteriosis, Vibrio parahemolyticus and Listeriosis
• Mycotic food borne infections include, Aspergillus, Candida
spp., Viral food borne infections include hepatitis A ,as well
as parasites.

6. Salmonellosis
• The salmonellae are a group of organisms with over 2000 species.
• These organisms are capable of causing disease in animals and human
when taken into the body in sufficient numbers.
• Many salmonella species have a wide host range. These are the
organisms which commonly cause food poisoning.
• some salmonella species are associated with human disease and are
not known to affect animals e.g. S. typhi and Salmonella paratyphi.
• People who are carriers of the salmonellae contaminate the food.
• A heavy dose up to 10,000 -1,000,000 organisms per gram of food is
required to cause infection
• Salmonellae grow well on food and can live or exist for period in feces,
and on pastures.

7. Common food poisoning types of Salmonella
• Some of the salmonella species involved in food poisoning
include; Salmonella typhimurium, Salmonella enteritidis,
Salmonella dublin, Salmonella softenburg, Salmonella
virchow, Salmonella montevideo, Salmonella infantis, and
salmonella newport.
• These species are also involved in causing diarrhoea in
animals.

8. Salmonella food poisoning outbreaks
Outbreaks occur in different forms:
a). Sporadic cases involving only one or two persons in a household
b). Family outbreaks in which several members of the family are
affected.
c). Large outbreaks caused by a widely distributed infective food item
d). Institutional outbreaks which may be caused by a contaminated
single food item.

9. Factors associated with Salmonella food poisoning outbreaks
• Consumption of inadequately cooked or thawed meat or poultry,
• Cross-contamination of food from infected food handlers.
• Presence of flies, cockroaches, rats, in the food environment that
act as vectors of the disease.
Transmission to the food
• Salmonellae reach food in many different ways;
a) Directly from slaughter animals to food.
b) From human excreta, and transferred to food through hands,
utensils, equipment's, flies etc.
• Food poisoning is more likely to occur if the total number of
microorganisms present is high, A smaller number may have no ill
effect.

10. Foods involved
• Any food contaminated with salmonellae may be involved.
• However, foods commonly involved are animal derived foods such
as:
a. meat and meat products,
b. milk and milk products,
c. egg and egg products
Clinical symptoms
• The ordinary symptoms include abdominal pain, headache, diarrhea,
fever, vomiting, and malaise.
• In severe cases there is septicaemia with leucopeni
• Severe cases in babies, young children , the sick and in elderly
persons. The mortality is upto 13 %.

11. Control measures
• Efficient refrigeration and hygienic handling of food.
• Consumption of properly cooked meat,
• Complete thawing of frozen meats and adequate cooking,
• Heat processing of meat, milk , fish and poultry to destroy
salmonella organisms in food.
Campylobacteriosis
• Campylobacter are a group of spiral organisms.
• Campylobacter jejuni occur in large numbers in cattle feces, and
poultry as normal flora.

12. Disease in human
• Campylobacter jejuni and C. coli cause illness characterized by
diarrhoea, abdominal pain, fever, nausea, vomiting.
control measures
• Thorough cooking of all foodstuffs derived from animal
sources.
• Prevention of re-contamination after cooking.
• Proper refrigeration of foods.
• Recognition, control and prevention of campylobacter
infections in animals, and Maintenance of high standard of
hygiene.

13. Escherichia coli food borne infection
• Escherichia coli are potential food poisoning pathogens
which are widely distributed in low numbers in food
environments.
• E. coli strains involved in food borne infection fall into the
following group:
1. Enteroinvasive E. coli (EIEC) and
Enteroinvasive E. coli
• EIEC strains cause illness that is characterized by watery
diarrhea in most patients.
• In addition, there is fever, nausea, and abdominal cramps.
• Bloody diarrhea may occur in fewer than 10 % of patients.

14. Enteroinvasive E. coli
• A relatively high dose (108 cells) is necessary to produce
disease in volunteers.
• The incubation period is 18 hours (range 2-48 hrs).
• Food borne spread is the usual way of transmission.
• The organism E. coli is heat sensitive, but resistant to freezing.
• • It grows poorly at 44 C-45 C, with no growth at 45.5 C.
Control measures
• Proper cooking of hamburger and other meats.
• Avoidance of cross-contamination of foods in the kitchen, and
• Good personal hygiene.

15. Shigellosis (Bacillary dysentery)
• Shigellosis is caused by members of the genus Shigella.
• The species involved include Shigella dysenteriae, Shigella flexneri,
Shigella boydii and Shigella sonei.
• All strains of shigella posses potent exotoxins which are
carbohydrate-lipid protein complexes.
• The infective dose is smaller than that of salmonellae, except S.
typhi.
Clinical symptom
• The illness begins 1 to 4 days after ingestion of bacteria and may
last 4 to 7 days, Symptoms include, watery or bloody diarrhea,
fever, stomach cramps, nausea or vomiting, dehydration in severe
cases and convulsions in young children.

16. Transmission
• Human cases and carriers are the only important sources of infection.
• Spread is by fecal-oral route, and person-to person transmission is
common.
• The bacteria leaves the body in stool of an infected person and infects
another person through contaminated hands, food, water, or objects
(toys, pens etc).
• Any type of food can transmit the shigella pathogens to cause disease
in man.
• Flies can spread shigella germs when they get into contact with
infected stool and then contaminate drinking water or food.
• Shigella organisms may remain viable in tap water for as long as 6
months, and in sea water for 2 to 5 months.

17. Control measures
• Practice good hygiene and sanitation.
• Wash hands well with water and soap each time you use the
ablution.
• The home and surroundings should be kept clean to prevent
contamination of food and water supply.
• Proper disposal of human waste or sewage.
• Keep kitchen work surfaces clean.
• Use boiled or chlorinated water
• Eat properly cooked of food,
• Drink properly pasteurized milk and

18. Cholera infection
• Cholera is caused by Vibrio cholera bacterium and that ingested in drink or
food.
• The organism multiply in the small intestine to produce a very potent
enterotoxin.
Transmission
• Man is the only natural host of the cholera vibrios.
• Spread of infection is from person-to-person, through contaminated
water or foods.
• Shrimps and vegetables are the most common carriers.
• Cholera is an infection of crowded poor class communities and it tends
to last in such areas.
• Cholera outbreaks occur either as explosive epidemics usually in non-
endemic areas or as protracted epidemic waves in endemic areas.

19. Clinical symptoms
• Cholera is typically characterized by the sudden onset of
vomiting and profuse watery diarrhea.
• Vomiting is frequently, but very rapid dehydration and
hypovolemic shock.
• Death may occur in 12 to 24 hrs due to rapid dehydration
Control measures
1. Provision of potable water
2. Proper sewage disposal
3. Proper cooking and hygienic handling of food
4. Monitoring of personal hygiene

20. Listeria monocytogenes infection
• Listeria monocytogenes is a gram positive bacterium that is
pathogenic to both animals and human beings.
• The organism is widespread in nature and is a transient constituent
of the intestinal flora excreted by 1-10% of healthy humans.
• It is extremely hardy and can survive for many years in the cold in
naturally infected sources.
Vehicle foods
• Listeria monocytogenese occurs after consumption of raw
vegetables, salads, raw milk, soft cheese, meat and meat products.
• milk, ice cream, cheese, poultry, sauerkraut, sea foods
contaminated by Listeria.

21. Clinical symptoms
• In human, Listeria monocytogenes causes abortion in pregnant
women and meningitis in newborn infants and immuno-
compromised adults.
• Pregnant women, infants and elderly people are particularly at
risk of infection with Listeria monocytogenes.
• The infection is fatal in susceptible individuals with a mortality of
25-30%.

22. Hepatitis A virus
161-34-489
➢Found in human intestinal and urinary tract and contaminated
water
➢Symptoms : Fever, fatigue, headache, nausea, stomach pain, vomiting,
“jaundice”
➢Incubation time: 2-10 months after contaminated food and water is
consumed
➢Food sources : Oyster, raw vegetables
Diseases Caused By Virus

23. ESDISEASE CAUSED BY PARRASIT
161-34-500

24. Giardiasiss
Parasite: Giardia doudenalis
• It A single cell microorganismcalled “protozoa, it looks like a small, hairy round worm.
Symptoms
➢Nausea, vomiting,
➢ abdominal pain,
➢ later stage are fever,
➢ swelling of tissues around the eyes,
➢muscle stiffness
Food Sources
• Undercooked pork
• Sausages
• Ground meats
• contaminated through meat grinders
161-34-500

25. Mycotoxin
• Mycotoxins are naturally occurring toxins produced by certain moulds (fungi)
and can be found in food.
• Exposure to mycotoxins is mostly by ingestion, but also occurs by the dermal.
• Mycotoxins have various acute and chronic effects on humans and animals
Symptoms:
• Dermatitis, memory loss, balance issues, acid reflux, cough, rhinitis, nose
bleeds, cold and flu-like symptoms, headache, bleeding lungs, seizures, and
fever.
Food Source:
• The moulds grow on a variety of different crops and foodstuffs including
cereals, nuts, spices, dried fruits, apples and coffee beans, often under warm
and humid conditions.
Control measures
Can mycotoxins be destroyed by heating or by cooking the product, most
moulds are heat-sensitive and are destroyed by pasteurisation.

26. Some Recommendation
❖ Hand washing is the most effective way to stop the spread of
illness.
❖ Separate raw, cooked, and ready-to-eat foods while shopping,
preparing or storing foods.
❖ Cook foods to a safe temperatureto kill microorganisms.
AVOID.
❖Raw (unpasteurized) milk or milk products
❖Raw or partially cooked eggs and foods containing raw eggs
❖Raw and undercooked meat and poultry
❖Unpasteurized juices
AVOID