FOOD BORNE DISEASES

 

Food borne illnesses are conditions of distress following the ingestion of food or drink. Such illnesses may strike one person or hundreds of persons in a single outbreak, and may be only mildly and temporarily unpleasant, or fatal. They are microbial and non – microbial in origin.

There are 11 major types of food borne illnesses: -

1. Indigestion

2. Food intolerance or food sensitivity

3. Algae toxins

4. Metal poisons

5. Phyllotoxins

6. Manufactured agricultural & household chemicals

7. Zootoxins

8. Protozoan disease

9. Infestation

10. Microbial infections

11. Bacterial & fungal food intoxications.

1. INDIGESTION: - is acute food borne distress which follows wilful neglect or violation of good eating habits. Symptoms of distress, acute abdominal pains, and vomiting.

2. FOOD INTOLERANCE OR SENSITIVITY: - food sensitivities are the food related reactions termed allergy, immunological hypersensitivity – i.e., manifestation of the antigen – antibody reactions following ingestion or contact with food hypersensitivity to milk, wheat flour & eggs is common.

3. ALGAE TOXINS: - Three divisions of algae namely: -

• Pyrrophyta (dinoflagellates) e.g., Gonyaulax Catenella, G. monilata.

• Cyanophyta (blue – green algae) e.g., anabaena flos – aquae, microcystis aeruginosa.

• Chrysophyta (golden brown algae) e.g., prymnesium parvum. All the organisms occur both in fresh & marine waters, but almost invariably incidents of shellfish poisoning occur in seawater.

4. METAL POISONS: - Both mineral and organic material toxic to man & animals are widespread in environment. They occur in foods, often as normal constituents. The prominent intoxicating mineral elements are arsenic, lead, mercury, and selenium

5. PHYLLOTOXINS: - many plants produce substances with pharmacological and toxic effects on humans and animals e.g.

• ANTIENZYMES: - plant - soya beans, legumes, potato. Action – trypsin.

• CARCINOGENS: - plant – senecio. Action – liver damage.

• GOITROGENS: - plant – cabbage and some fruits. Action – enlargement of thyroid.

6. Manufactured agricultural & household chemicals: - insecticides, pesticides, growth regulators, fungicides, and growth simulators e.g. cryolite, lead arsenate, DDT(dichloride – diphenyl – tri – chloroethane). Most chemicals are looked upon as adulterants of food. Regulatory control dictates the care that must be exercised in their handling & use, time of application & residues permitted.

7. ZOOTOXINS: - Zootoxins are associated only with freshwater & marine foods. It is microbial deterioration of the fish after capture.

8. PROTAZOAN DISEASE: - e.g., Amebiasis – or amoebic dysentery. Its prevalence is influenced by cultural practicelike by disposal of human waste in such a way that food & water are contaminated. Effective sanitation is necessary to control amebiasis.

9. INFESTATIONS: - Helminthic infestations are illness caused by cestodes (parasitic, highly segmented flat – worms), trematodes (parasitic, unsegmented flatworms) and nematodes (long, cylindrical, unsegmented worms). Many infestations are associated with foods characteristic of specific geographic areas. all food borne infestations entre the human through food & water, it is also transferred during the handling of the meat. E.g., Ascariasis, enterobiases, taeniasis.

10. MICROBIAL INFECTIONS: -

INTESTINAL ILLNESSES

I. streptococci: - it is caused by streptococcus phylogenies. It is responsible for acute, pus forming infections. Common vehicles for spreading the disease are raw milk & cream contaminated by infected farmers.

II. Salmonella: - caused by Salmonella. Salmonella, or enteric fever lies affected humans for centuries. The symptoms are fever, septicemia, and gastroenteritis. The agent of thyroid is Salmonella typhi. Symptoms – high fever incidence occur through contamination of well water, milk & foods.

III. Shigellosis: - shigellosis of bacillary dysentery is caused by organism belonging to genus shigella. Commonly associated with milk & ice cream.

IV. Cholera: - it is transmitted by contaminated water, fruits, vegetables, raw/ half cooked fish. Caused by vibrio cholera

NON-INTESTINAL ILLNESSES

(i) Tuberculosis: caused by Mycobacterium tuberculosis. Sputum, nasal exudates, unpasteurized milk, uninspected meat & poultry. Food related TB is less often respiratory than gastrointestinal, skeletal, and glandular. & Muscular.

(ii) Listeriosis: - caused by listeria, monocytogenes.

(iii) Q fever: - caused by Coxiella Burnette. Out breaks seen in meat packaging plants. Causes fever, severe pneumonia.

11. BACTERIAL & FUNGAL FOODBORNE INTOXICATION: - Although many different organisms can grow in foods, only few produce toxins that make the food dangerous to eat among bacteria e.g., are staphylococcus aureus, clostridium perfringens, c. botulinum & bacillus cereus. Among fungi e.g., Claviceps purpurea fusarium, aspergillus penicillium.

(i) S. Aureus – it resides in the mucous of nose & throat region. The bacteria leave the nose & month in nasal secretions. During coughing & sneezing. It causes osmoles, boils, abscesses, meningitis, and pneumonia. S.A. produces enterotoxins (toxins). It causes irritation of intestinal tract, cramps, coma, and death.

(ii) Botulism: - It is neuroparalytic disease causes by consuming foods contaminating toxin of clostridium botulinum. Faulty vegetable processing, fish & FP, fruits, milk & MP.

(iii) Ergotism: - Caused by Claviceps purpurea, a fungal pathogen of rye, barley, wheat and produces a toxic product called ergot. Fungal tissue grows on the grains having alkaloids which have toxic characteristics.

(iv) Aflatoxins: - Caused by mold aspergillus flowers. A wide variety of commodities. Like almonds, bakery products, millet, peanuts, wheat flour etc. symptoms are jaundice, hepatitis, hypertension, carcinogenic in nature.