Zoonoses 4th year 23-4-2017 Dr.Osamah Muwaffag
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Tuberculosis
Mycobacteum spp. (M. farcinum, M. avium, M. bovis, M. tuberculosis)
Human:
1. Pulmonary
a. Productive cough, fever, weight loss, fatigue, night sweats,
chest pain, hemoptysis.
2. Extrapulmonary:
b. Cervical lymphadenitis (scrofula),
c. meningitis,
d. osteomyelitis,
e. pericarditis;
f. also associated with infection of most other organs.
g. Typically, encapsulated inflammatory nodules (tubercles) with
epithelioid and giant cells surrounding caseous or liquefied
center.
Incubation period:
1. 4-12 weeks for observable lesion (e.g., lung nodule)
Case fatality rate:
1. Severe outcome more likely with primary infection in young or
immunodeficient (e.g., AIDS).
Confirmatory tests:
1. Direct microscopic examination (presumptive)
2. aerobic culture of lesion material (pus, sputum).
Occurrence:
1. Worldwide.
Transmission:
2. Primarily inhalation of infectious droplets or droplet nuclei from
pulmonary lesion.
Zoonoses 4th year 23-4-2017 Dr.Osamah Muwaffag
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3. Ingestion , particularly raw milk from cow with mammary lesion.
4. People are reservoir and main source for M. tuberculosis; cattle for
M. bovis.
CONTROL AND PREVENTION
1. Prolonged
therapy
(several
months)
with
isoniazid,
dihydrostreptomycin, ethambutol, rifampicin, pyrazinamide.
2. Surgical excision of affected lymph nodes may be needed.
3. Pasteurize milk.
4. Immunize high-risk groups with BCG.
5. Find cases with use of tuberculin test (cattle, people, primates).
6. Slaughter tuberculin reactor cattle.
7. Depopulate Tuberculous poultry flocks.
8. Screen radiographically tuberculin-positive people.
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CIostridium Perfringens Food Poisoning
Clostridium perfringens, commonly type A, types C and D unusual.
Human:
1. Sudden onset, nausea, diarrhea, cramps,
2. gas formation with distention of large and small bowel
3. afebrile, rarely vomiting.
4. Necrotic enteritis (type C), or gastroenteritis (type D).
Incubation period: 5-24 hours, usually 10-12 hours.
Case fatality rate: Usually benign, may be fatal in debilitated individuals.
Confirmatory tests:
1. Microscopic examination (presumptive)
2. Quantitative culture (confirmatory, > ld/gm) of suspect food or
3. patient feces (> 106/gm).
4. Serotyping has been a useful epidemiologic tool in some areas.
Zoonoses 4th year 23-4-2017 Dr.Osamah Muwaffag
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Occurrence:
1. Worldwide.
2. Reservoir is soil,
3. source of food contamination usually intestinal flora of herbivores.
4. Restaurant and institutional outbreaks associated with improper
cooking and storage of meat foods. in food.
Transmission: Ingestion of large numbers of viable vegetative organisms
CONTROL AND PREVENTION
1. Supportive treatment.
2. Vaccinate pregnant ewes and nursing lambs with polyvalent toxoid.
3. thoroughly cook foods containing meat to destroy vegetative (often
heat-resistant) cells.
4. Rapidly cool and refrigerate food if not to be eaten immediately.
5. Reheat stored foods rapidly.
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Staphylococcosis
Stuphylococcus ureus, 6 enterotoxin types
Human:
1. Predominantly subclinical infections.
2. Gastroenteritis (enterotoxin food poisoning): sudden onset,
salivation, nausea, abdominal cramps, vomiting, diarrhea;
prostration common.
3. Suppuration: in any tissue, but usually skin (impetigo, boils),
lung (pneumonia), mammae (mastitis or abscess), endocardium,
or periosteum.
4. Toxic epidermal necrosis: noninflammatory separation of
epidermis, especially in newborn.
Incubation period
1. Gastroenteritis: 0.5-7 hours, usually 2-4 hours.
Zoonoses 4th year 23-4-2017 Dr.Osamah Muwaffag
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2. Suppuration: 4-10 days.
Case fatality rate:
1. Gastroenteritis: deaths only in the debilitated or those with cardiac
problems.
2. Suppuration: unusual, following septicemia.
Confirmatory tests:
1. Culture lesion material (suppuration) or vomitus, feces, and food
(gastroenteritis).
2. Demonstrate enterotoxin if food poisoning.
3. Bacteriophage typing and antibiogram are epidemiologic aids.
Occurrence:
1. Worldwide.
2. All species susceptible to infection,
3. Greatest risk of suppuration in neonates, new mothers, the debilitated,
surgical patients, those on extended steroid or antibiotic therapy.
4. Poor personal hygiene predisposes.
Transmission:
1. Gastroenteritis: usually by ingestion of heat-stable toxin preformed in
food, but toxin may form in intestine of severely stressed or heavily
exposed person.
2. Suppuration: direct contact or fomites; airborne common (hospital
problem); infective dose fairly high in most healthy subjects.
CONTROL AND PREVENTION
Practice personal hygiene.
1. Ensure aseptic surgery.
2. Use antibiotics judiciously.
3. Cover draining lesions.
4. Use triple dye (brilliant green, proflavine hemisulfate, crystal violet)
on umbilicus of newborn.
Zoonoses 4th year 23-4-2017 Dr.Osamah Muwaffag
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5. Ensure proper food hygiene.
6. Constantly control food temperature.
7. Pasteurize milk.
8. Detect and eliminate reservoir in outbreaks.
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Streptococcosis
Streptococcus spp., Lancefield groups A (S. pyogenes), B (S. agalactiae),
C (S. equi), D (S. bovis), F, G, H, L, and M
Human:
1. Suppurative disease
2. Septicemia
3. pneumonia
4. puerperal fever
5. endocarditis,
6. arthritis
7. rash (scarlet fever)
8. pharyngitis
9. impetigo
10. Rheumatic fever or nephritis delayed sequelae of
11. group A.
Animal: Bovine mastitis and equine abortion.
Incubation period: 1-3 days.
Case fatality rate: 20%-50% in neonates, increasing with immaturity and
earlier age at onset.
Confirmatory tests:
1. Culture lesion material
2. hemolysin test isolate.
3. Lancefield grouping or CAMP test may be epidemiologic aid.
Zoonoses 4th year 23-4-2017 Dr.Osamah Muwaffag
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Occurrence:
1. Worldwide.
2. Neonates, immunocompromised individuals at greatest risk.
3. Crowding, poor hygiene, hot humid climates, skin trauma predispose.
Transmission:
1. Inhalation
2. direct contact
3. ingestion
CONTROL AND PREVENTION
1. Treat patients with penicillin or erythromycin
2. Practice personal hygiene.
3. Culture human pharyngitis and treat group A infections promptly to
prevent
4. delayed sequelae.
5. Screen pregnant women for group B genital carriage so can initiate
newborn therapy.
6. Use bacterins against S. equi in foals.
7. Avoid crowding.
8. Pasteurize milk.
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Colibacillosis
1. Escherichia coli, multiple somatic (0), capsular (K), and flagellar (H)
antigens.
2. Some strains produce heat-labile (LT) and/or heat-stable (ST)
enterotoxins.
Human:
1. Diarrhea, which may be complicated by other syndromes often
associated with certain specific serotypes
2. hemolytic uremic syndrome (0157H7).
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3. Enteroinvasive strains cause fever, dysentery.
4. Enterotoxigenic strains may cause dehydration and shock.
5. Enterohemorrhagic strains may cause HUS, hemorrhagic colitis, or
thrombotic thrombocytopenic purpura ('ITP).
Incubation period: 0.5-5 days, usually 12-72 hours.
Case fatality rate: May be high in neonates with diarrhea, otherwise low
unless underlying disease or develops nonenteric syndrome such as
HUS or 'ITP with brain damage.
Confirmatory tests:
1. Culture of fresh feces (diarrhea) or acute blood (systemic).
2. Serotyping aids in identifying potentially pathogenic strains as well as
the possible source.
Occurrence:
1. Worldwide.
2. More common with poor hygiene, fecal contaminated raw or
undercooked food.
Transmission:
1. Ingestion via fecal-oral cycle; often foodborne.
2. animal reservoirs important for spread via milk and meat.
CONTROL AND PREVENTION
1. Treat patients
2. Practice good personal hygiene
3. Thoroughly cook food.
4. prevent fecal contamination.
5. Pasteurize milk.
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Zoonoses 4th year 23-4-2017 Dr.Osamah Muwaffag
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Vibriosis
Aeromonas hydrophila, Vibrio spp.
Human:
1. Gastroenteritis: diarrhea, occasionally bloody; abdominal pain,
vomiting, fever.
2. Wound infection: a variety of skin lesions, including cellulitis and
necrosis, usually progressing to systemic involvement.
3. Septicemia: systemic illness, fever, or hypotension, no wound
preceding.
Incubation period 4-96 hours, usually 12-24 hours.
Case fatality rate: Septicemia: may exceed 50%; wound infection: up to
25%; gastroenteritis: fatality unusual. Risk greater in those with
underlying debility, e.g. liver disease.
Confirmatory tests: Culture feces (diarrhea), blood (septicemia), or
lesion material.
Occurrence:
1. Worldwide
2. more often in coastal areas.
3. More frequent in warm months in temperate regions.
Transmission:
A. Ingestion of raw or undercooked shellfish (oysters), freshwater or
marine fish.
CONTROL AND PREVENTION
1. Supportive therapy
2. surgical debridement of wounds.
3. Treat severely affected with tetracyclines, aminoglycosides.
4. Cook all fish and shellfish just before consumption.
Zoonoses 4th year 23-4-2017 Dr.Osamah Muwaffag
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5. Ensure hygiene in fish markets and kitchens.
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Salmonellosis
Salmonella spp. (approximately 2,000 serotypes)
Human:
1. Most infections subclinical.
2. Usual clinical signs are diarrhea, vomiting, low-grade fever.
3. Sometimes progresses to dehydration, prostration, death, especially in
very young or very old.
4. Septic syndrome (enteric fever) has high-spiking fever, septicemia,
splenomegaly, headache.
Incubation period 6-72 hours, usually 12-36.
Case Stality rate: 1%-2% with most serotypes, particular risk in very
young, aged, and debilitated.
Confirmatory tests:
1. Culture feces, affected tissue, or fluid.
2. Bacteriophage typing aids in epidemiologic investigation.
3. Agglutination test of serum
Occurrence: Worldwide.
Transmission:
1. Ingestion, usually through variations of the fecal-oral cycle,
2. S. dublin in raw milk from cow with udder infection.
CONTROL AND PREVENTION
1. Treat patients symptomatically, including fluids and
2. electrolytes
3. Sanitation very important.
4. Cook food thoroughly.
Zoonoses 4th year 23-4-2017 Dr.Osamah Muwaffag
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5. Control rodents, birds, insects.
6. Practice personal hygiene.
7. Avoid stress.
8. Use Salmonella-free feed for livestock, poultry, and pets.
9. Adequately heat meat, bone, and fish meal to be used in animal feed.
10. Obtain hatching eggs from Salmunella-free flocks.
11. Pasteurize milk.
12. Prohibit sale of pet turtles and other Salmonella carriers.
13. Educate food handlers.
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Shigellosis
AGENT
Shigella spp.
Human:
1. Bloody diarrhea
2. tenesmus
3. fever
4. nausea.
Incubation period: 1-4 days.
Case fatality rate: Insignificant, except may be up to 20% for debilitated
Occurrence: Worldwide
Transmission: Via fecal-oral route with some mechanical vectors (e.g.,
flies).
CONTROL AND PREVENTION
1. Treat patients
2. Personal hygiene.
3. Good sanitation practices
4. fly contro