Food

FOODBORNE INTOXICATIONS(Food poisoning)

Dr. Nadia Aziz
F.A.B.C.M. Lecturer
Department of community medicine
Medical college, Baghdad University

1-Define what is food intoxication.

2-describe types of food poisining.
3-discuss clinical features,diagnosis,occurrence & measures of control of food intoxication.
objectives

Including foodborne intoxications and foodborne infections, are terms applied to illnesses acquired through consumption of contaminated food
also include those caused by chemical contaminants such as heavy metals and organic compounds.

Foodborne diseases

The more frequent causes are:
1) Toxins elaborated by bacterial growth in the food before consumption
Like : Clostridium botulinum, Staphylococcus aureus and Bacillus cereus
or in the intestines Clostridium perfringens
Foodborne diseases


2) bacterial, viral, or parasitic infections (brucellosis, Escherichia coli, hepatitis A, salmonellosis and infection with vibrios etc…)
3) toxins produced by harmful algal species (ciguatera fish poisoning, paralytic, neurotoxic, diarrhoeic or amnesic shellfish poisoning).

Foodborne diseases

Foodborne disease outbreaks are recognized by the occurrence of
illness within usually short time period (a few hours to a few weeks)
after a meal, among individuals who have consumed foods in common.

Foodborne diseases

Prompt and thorough laboratory evaluation of cases and implicated foods is essential.

Single cases of foodborne disease are difficult to identify unless, as in botulism, there is a distinctive clinical syndrome.

Foodborne diseases

Ultimately, prevention depends on educating food handlers about proper practices in cooking and storage of food and personal hygiene.

Prevention

1. Keep Clean.

2. Separate raw and cooked.
3. Cook thoroughly.
4. Keep food at safe temperatures.
5. Use safe water and raw materials.

WHO Five Keys to Safer Food

An intoxication (not an infection) of
abrupt severe nausea, vomiting ,
cramps,and prostration,
often accompanied by diarrhea and sometimes with subnormal temperature and lowered blood pressure.
Deaths are rare
illness commonly lasts only a day or two

STAPHYLOCOCCAL FOODINTOXICATION ICD-10 A05.0

In outbreak:
Recovery of staphylococci (105/g of food) on culture media
Detection of enterotoxin from food item.
Absence of staphylococci on culture from heated food does not rule out the diagnosis
Diagnosis


A Gram stain of the food may disclose the organisms that have been heat killed.
Isolation of organisms from stools or vomitus of 2 or more ill persons

Diagnosis

Several enterotoxins of Staphylococcus aureus, stable at boiling temperature.
Staphylococci produce the toxins at levels of water activity too low for the growth of many bacteria.
Occurrence
About 25% of people are carriers of this pathogen.

Toxic agent

Reservoir
Humans in most instances; occasionally cows with infected udders, as well as dogs and fowl.

STAPHYLOCOCCAL INTOXICATION

Ingestion of a food containing staph enterotoxin like salad dressings, sandwiches, meat products & cheese.

When these foods remain at room temperature for several hours before being eaten, toxin-producing staphylococci multiply and elaborate the heat-stable toxin.


Mode of transmission

Organisms may be of human origin from purulent discharges of an infected finger or eye, abscesses, acne form eruptions, nasopharyngeal secretions,
or of bovine origin, such as contaminated milk or milk products, especially cheese.

Mode of transmission

Incubation period
30 minutes to 8 hours, usually 2–4 hours.

STAPHYLOCOCCAL INTOXICATION

A. Preventive measures:
1) Educate food handlers about:
(a) Strict food hygiene, sanitation and cleanliness of kitchens, proper temperature control, handwashing, cleaning of fingernails
(b) The danger of working with exposed skin, nose or eye infections and uncovered wounds.

Methods of control

2) Reduce food-handling time (from initial preparation to service), no more than 4 hours at ambient temperature.
(above 60°C) or cold (below 4°C) in shallow containers and covered.
3) Temporarily exclude people with boils, abscesses and other purulent lesions of hands, face or nose from food handling.


Methods of control

B. Control of patient, contacts and the immediate environment:

1) Report to local health authority: Class 4.
Control is of outbreaks, single cases are rarely identified.
2) Specific treatment: Fluid replacement when indicated
Methods of control

C. Epidemic measures:

1) Conduct an epidemiological investigation including interviews of ill and well persons to determine the association of illness with consumption of a given food.
2) Inquire about the origin of incriminated food
STAPHYLOCOCCAL INTOXICATION

C. Epidemic measures:

3) Search for food handlers with skin infections, Culture all purulent lesions and collect nasal
swabs from all foodhandlers.

STAPHYLOCOCCAL INTOXICATION

An intestinal disorder characterized by sudden onset of colic followed by diarrhea, nausea is common.
Generally a mild disease of short duration, 1 day or less,
rarely fatal in healthy people.
Outbreaks of severe disease with high case-fatality rates associated with a necrotizing enteritis
CLOSTRIDIUM PERFRINGENS INTOXICATION ICD-10 A05.2


In outbreak :
Diagnosis is confirmed by demonstration of
Clostridium perfringens in anaerobic cultures of food (105/g) or patients’ stool (106/g).
Detection of enterotoxin in patients’ stool also confirms the diagnosis.

Diagnosis

Infectious agent
Type A strains of C. perfringens (C. welchii)
cause typical food poisoning outbreaks
Type C strains cause necrotizing enteritis.

CLOSTRIDIUM PERFRINGENS INTOXICATION

Reservoir
GI tract of healthy people and animals (cattle, fish, pigs and poultry).

CLOSTRIDIUM PERFRINGENS INTOXICATION

Ingestion of food containing soil or feces and then held under conditions that permit multiplication of the organism.
Almost all outbreaks are associated with inadequately heated or reheated Meats.
Spores survive normal cooking temperatures
Incubation period
From 6 -24 hours, usually 10–12 hours.


Mode of transmission

An intoxication characterized by:

sudden onset of nausea and vomiting
in others by colic and diarrhea.
Illness generally persists no longer than 24 hours and is rarely fatal.

BACILLUS CEREUS FOOD INTOXICATION ICD-10 A05.4

In outbreak, diagnosis is confirmed through cultures
of suspected food (more than 105 - 106 organisms per gram of food).
Enterotoxin testing is valuable but may not be widely available.

Diagnosis

Bacillus cereus, an aerobic spore former.
Two enterotoxins have been identified:
1-Heat stable causing vomiting, is produced in food when B. cereus levels reach 105 colony /g of food.
2-Heat labile causing diarrhea, formed in the small intestine of the human host.

Toxic agent

Reservoir
A ubiquitous organism in soil and environment
Mode of transmission
Ingestion of food kept at ambient temperatures after cooking.
Outbreaks associated with vomiting have been most commonly associated with cooked rice.

BACILLUS CEREUS INTOXICATION

Incubation period
From 0.5 to 6 hours in cases where vomiting is the predominant symptom
From 6 to 24 hours where diarrhea predominates.
Preventive measures:
Foods should not remain at ambient temperature after cooking

BACILLUS CEREUS INTOXICATION

Human botulism is a serious but relatively rare intoxication caused by potent preformed toxins
produced by Clostridium botulinum.
There are 3 forms of botulism:
1- foodborne (the classic form)
2-wound
3-intestinal (infant and adult) botulism.


BOTULISM ICD-10 A05.1

All types share the flaccid paralysis that results from botulinum neurotoxin.

Foodborne botulism is a severe intoxication resulting from ingestion of preformed toxin present in contaminated food.

BOTULISM

The characteristic early symptoms and signs are:
Marked fatigue, weakness and
Vertigo, usually followed by
Blurred vision, dry mouth, and difficulty in swallowing and speaking.
Vomiting, diarrhea, constipation and abdominal swelling may occur.

BOTULISM

Neurological symptoms always descend through the body
Paralysis of breathing muscles can cause loss of breathing and death.
There is no fever and no loss of consciousness.
The case-fatality rate is 5%–10%.


BOTULISM



Infant botulism has in some cases been associated with ingestion of honey contaminated with botulism spores.
It may cause an estimated 5% of cases of sudden infant death syndrome (SIDS).

BOTULISM

demonstration of botulinum toxin in serum, stool, gastric aspirate or incriminated food, or through culture of C. botulinum from gastric aspirate or stool of the patients
Clostridium botulinum, a spore-forming anaerobic bacillus, isolated from soil, seafood and meat from marine mammals.
Toxin is produced in canned, low acid or alkaline foods.
Toxin is destroyed by boiling

Diagnosis & Infectious agent

Reservoir
Spores, ubiquitous in soil, honey & in the intestinal tract of animals.

Incubation period
usually within 12–36 hours


BOTULISM

1) Report to local health authority: Class 2

2) Specific treatment: Intravenous administration of 1 vial of polyvalent (AB or ABE) botulinum antitoxin as soon as possible,
Antibiotics do not improve the course of the disease.

Control of patient, contacts and the immediate environment

A bacterial disease manifested by:
Acute enterocolitis, headache, abdominal pain, diarrhea, nausea and sometimes vomiting.
Dehydration, especially among infants or in the elderly, may be severe.
Fever is almost always present.
Deaths are uncommon, except in the very young, the very old, the debilitated and the immunosuppressed.

SALMONELLOSIS ICD-10 A02

Salmonella isolated from feces during acute stages of enterocolitis.
In the recently proposed nomenclature for Salmonella the agent formerly known as S. typhi is called S. enterica
Salmonella enterica serovar Typhimurium (commonly S. Typhimurium) and
Salmonella enterica serovar Enteritidis (S. Enteritidis) are the most commonly reported
Diagnosis & Infectious agents


Occurrence
Worldwide, contaminated food, mainly of animal origin, is the predominant mode of transmission.
The incidence rate of infection is highest in infants and young children.
person-to-person spread can also occur

SALMONELLOSIS

Reservoir
Domestic and wild animals, including poultry, swine, cattle, rodents and pets such as iguanas, turtles, chicks, dogs and cats; also humans, i.e. patients,
convalescent carriers
Chronic carriers are rare in humans
but prevalent in animals and birds.

SALMONELLOSIS

Ingestion of the organisms in food from infected animals or contaminated by feces of an infected animal or person. This includes eggs, raw milk, contaminated water, meat & poultry.
Maternity units with infected (at times asymptomatic) infants, are sources of further spread.

Mode of transmission

Incubation period
From 6 to 72 hours, usually about 12–36 hours.
Period of communicability
Throughout the course of infection.
A temporary carrier state occasionally continues for months, especially in infants.

SALMONELLOSIS

Increased by:
Achlorhydria, antacid treatment, gastrointestinal surgery,
broad-spectrum antibiotherapy, neoplastic disease, immunosuppressive treatment and other debilitating conditions including malnutrition.

Susceptibility

A. Preventive measures:
1) Educate all food handlers about the ways of proper preparation & handling of food.
2) Exclude individuals with diarrhea from food handling and from care of hospitalized patients, the elderly and children.
Methods of control

Specific treatment:

rehydration and electrolyte replacement Antibiotics may not eliminate the carrier state
ciprofloxacin is highly effective ampicillin or amoxicillin may also be used.
Patients infected with HIV may require lifelong treatment to prevent Salmonella septicemia.


B. Control of patient, contacts and the immediate environment

• Organism

• Incubation period
• Signs & Symptoms
• Duration
• Food Sources
• Staphylococcus aureus
• 30 min- 8 hrs
• Sudden onset of severe nausea and vomiting.
• 24-48 hours
• meats, egg, salads, cream pastries
• Clostridiumperfringens
• 8–24 hours
• Intense abdominal cramps, watery diarrhea
• 24hours
• Meats, poultry
• Bacillus cereus
• 6 -24 hrs
• Abdominal cramps, watery diarrhea,
• 24-48 hours
• Cooked rice
• Clostridiumbotulinum
• 12-36 hours
• Vomiting, diarrhea, blurred vision, muscle weakness, respiratory failure and death
• Variable
• Improperly canned foods, especially home-canned vegetables
• Salmonella
• 6-72 hours
• Diarrhea, fever, abdominal cramps, vomiting
• 4-7 days
• Eggs, poultry, meat, unpasteurized milk or juice, cheese


Thank you
&
Good Luck
With Quiz

1. Mention 3 organisms cause food intoxication.

2. Mention 3 documents of WHO for safe food.