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Fecal oral infection:
Food-borne infection (ingestion infection). Contaminated food: vehicles are milk & any food that may be contaminated by handling, flies, water, or dust, & sewage-polluted water.
Fecal oral infection:
Food-borne infection (ingestion infection).
Contaminated food: vehicles are milk & any food that
may be contaminated by handling, flies, water, or
dust, & sewage-polluted water.
Mode of transmission
• Health promotion
• Case finding &
• Isolation &
• ttt & release
• Prevent complications
& care of
A) General Sanitation of Environment:
Safe water supply,
Sanitary wastes disposal (refuse & sewage),
Insect control (flies & cockroaches).
Food sanitation includes control of food handlers
B)Health education :
proper clean habits (including clean hands)
I. Control of Cases “FNIDTRR”:
Case-finding: needs efficient medical care (clinical & lab
Notification to the LHO.
Isolation: allowed at home when sanitary requirements are
fulfilled, otherwise must be at fever hospital.
Disinfection: - concurrent: excreta (1% crude phenol), articles
- terminal for objects & cleaning of the room.
Treatment: general & specific chemotherapy.
Polio Hepatitis A Hepatitis E
IP 7- 14 d 15- 50 d 21- 42 d
water or food
Infectivity From IP to
Last week of IP till Jaundice
Agent -Polio virus Picorna virus
An Egyptian stele shows a
priest with a deformity of
his leg characteristic of the
flaccid paralysis typical of
Acute viral infectious disease may lead to flaccid
Poliomyelitis may be near worldwide eradication.
Localized outbreaks may occur at any time.
II Oct 1999
Poliovirus has 3 antigenically distinct types.
• Polioviruses have affinity to the nervous system.
• Relatively resistant & survive for long time under suitable
Boiling of milk
Cases: all clinical forms
Carriers: all types (incubatory. Convalescent, healthy & contact who
are temporary carrier .
In endemic area health carrier are most frequent due to polluted
Contact & healthy
• About 2weeks.
• Last days of IP.
• Temporary, for some
• Infectious for about 6-8
weeks (clinical period).
Age: incidence usually from 6 Ms-5 Ys. By compulsory vaccination
programs there is age shift to adolescents & young adults
Sex: Paralytic polio is more in males than females.
Immunity: a- Naturally acquired Immunity Maternally
acquired persists for 6 Ms. Exposure to infection by any form
of clinical disease gives lasting, type-specific immunity. 2nd
attack rarely occurs, from type-different poliovirus infection.
b- Artificially induced immunity: by immunization.
• Throat washing or stools
• Serological (neutralizing Ab): rising titer
In the abortive stage, is practically impossible.
Diagnosis is suspected only when non-paralytic or
paralytic picture appears.
Differential diagnosis: Other causes of acute flaccid
paralysis as Gillian-Barrie syndrome & transverse myelitis.
• Passive immunization (Sero-prophylaxis):
Normal human Ig (0.3 ml/kg BW)
Exposed susceptible (pre exposure – rapidly post
• Active immunization:
Sabin & Salk
• Oral, live attenuated trivalent vaccine made of
the 3 types, of polioviruses.
• 2, 4 and 6 Ms of age
• 3 drops orally on the tongue.
• Recently a zero dose is giving after birth as
• Booster Immunization: a booster dose is
given at 9 Ms, 18-24 Ms, and school age.
Live attenuated viruses of the vaccine invade
& multiply in the intestinal cells, stimulating
humoral & local cellular immunity:
Humoral immunity: by neutralizing antibodies in
serum. It protects the CNS Against invasion by
Cellular immunity: local tissue immunity in the
intestinal mucosa so prevents establishment of
infection in the intestine, and so prevent a carrier.
Gives humoral & tissue immunity
Excreted in stools, disseminate infection in community
Used in mass immunization.
Protective value up to 95%,
Life long immunity.
regenerated below 4 C
Paralysis: very rarely (1/5 million)
Trivalent vaccine, inactivated (formalin).
Used in non-endemic areas & with Sabin vaccine in
4 doses, 1.0 ml each, IM, starting at 4 months of age.
1st 3 doses 6-8 weeks apart, 4th dose 7 months later.
Booster dose : at school age, and whenever an epidemic
or outbreak threatens.
Action: Salk vaccine gives humoral immunity.
No cellular immunity
Protective Value: prevents <90% of paralytic
cases & lowers severity of paralytic effect.
Salk is given in Egypt as quadruple Salk DPT,
IM, 2 doses at 4 &6 Ms
Due to the preventive value of polio vaccines & reluctance of
some parents to take their children for immunization, or missing
1-2 doses of 1ry immunization, periodic polio vaccination
campaigns are arranged, for better coverage & complete
immunization of infants & young children <5 ys.
Booster v. or sero-
Mass oral v.
• Definition: communicable food borne acute viral disease
involving the liver endemic in developing countries, and
gives sporadic cases, usually in outbreaks in confined
groups (camps, military units, boarding school& daycare
• Causative agent: viral hepatitis A virus: RNA virus,
relatively resistant outside the body
• Reservoir: man as incubatory carriers and cases (mild or
• Mode of transmission:
1-faeco-oral 2-parenteral rarely during viraemia
• IP: average 4 weeks (15-50 days)
• Clinical Picture:
1- In apparent cases: mild an-icteric cases “influenza-like picture
(non-specific syndrome) & pass unnoticed”.
2- Classical disease.
3- Severe fulminate rapidly fatal disease.
• Dark urine
• IgM in
• ↑ liver enz.
• Active immunization
• Case Finding.
• Notification: LHA.
• Isolation: at home
• Disinfection: feces, urine &
• Specific ttt: No
• Enlistment & Immunization:
within 2 weeks of exposure.
• Surveillance: for 6 weeks
• Food sanitation
• Epidemiologic study.
• Inactivated vaccine
1 ml IM(deltoid) “2 doses, 4 weeks apart”
• 1- At risk: Ch. Liver Dis., travelers, lab workers.
• Human Ig
Before or few days after exp
• 1- Contacts (within 2 wks)
2- At risk: travelers (before or within 2 wks)
• Occurrence: It is a newly identified zoonotic disease. It 1st
appeared in England 1989 among cows that were fed by animal
meat of carcasses of died animals after their crushing. The
change in the food of the cow (herbivorous animal) into feeding
by animal tissues induced a pathological condition in the cow.
• Causative agent: Proteinaceous non-living infectious particle
that is devoid of nucleic acid (not virus or viroid)
• Modes of transmission: Ingestion of infected meat of diseased
• Management: No specific ttt is known.
• Control measures:
1. Prevent feeding of living animals (as cattle) by died animal
tissues or bony meals.
2. At the international level:
a) All countries must ensure condemning & safe disposal of
all BSE affected animals & prevent their entry into free
b) Surveillance & compulsory notification for BSE disease.
3. Research for finding rapid diagnostic methods &
management in both animals & man.
Salmonellae have more than 2000 serotypes, of which
pathogens of Human disease is:
*Typhoidal salmonellae: S. typhi, & S. paratyphi A, B, C.
*Nontyphoidal salmonellae: Food poisoning &
• Typhoid: Salmonella typhi (typhoid bacillus), with a big number of
3 serotypes “A, B, C”
B is the most common
C is rare.
• It can remain viable in the environment (water, ice, milk, milk products,
ice-cream and other foods) for weeks.
• But it is readily destroyed by heat & disinfectants.
Last days of IP
Contact 2 wks
Fecal carriers:more common than urinary
Urinary: more frequent in endemic Schistosomiasis
Small intestine (Peyers
patches) & gall-bladder Feces Fecal carrier
Kidney Urine Urinary carrier
• 10-30 ys
• Markedly ↓ with ageAGE
• Male > Female
• Females: fecal carriers 5 times > males
• Significant ↑ during summer.SEASON
• Repeated subclinical infection (mainly), clinical
attack, or active immunizationIMMUNITY
Period of Infectivity:
Infectious from the last days of IP (incubatory carriers),
throughout disease, and for varied period (months, years or
lifetime) in a percent of convalescents (convalescent carriers).
2-Contact & healthy carriers:
Infectious about 2 weeks.
Incubation Period: 8-14 days
• Onset is usually gradual.
• Picture of disease varies whether
chemotherapy is given or not.
• Treated Cases:
Chemotherapy: ↓ Disease duration
& incidence of complications.
• FHMA (stepladder, evening, low pulse)
• Rash (macular rosy spots , abdomen,7th day , 25%)
• High fever, worse physical & mental condition,
• Abdominal distension & tenderness
• Gradual improvement
• Drop of temperature
Convalescence • Relapse(s) after 1-2 weeks: 10-20%, usually mild.
Infection by antimicrobial resistance strains & in children
(respiratory symptoms & diarrhea)
15-30% in untreated cases & ↓ with ttt to 1-2%.
of femoral vein
• Agglutination test (rising titer)
• High titer O & low titer H → Recent infections
• High titer H & low titer O → Past Infections
culture 2nd &
• Should be repeated for 3 times
• Practically valuable to detect carriers, rather than diagnosis
TAB (TABC) vaccine
•Adults: 2 doses of 0.5 & 1.0 ml SC, 4 weeks apart.
•Booster Dose: adult “1.0 ml” every 3 ys.
•Children >2 years can be given smaller dosage.
•Protective Value: 50-75% & may not be protective on
exposure to heavy infection
Typhoid Oral Vaccine
• Protective value: 65%
• 4 oral doses on alternate days
• Parental vaccine containing Vi Ag in single dose
Vaccination in endemic areas is given to
Occupational groups at-risk: Food handlers, Lab workers, HCW, waste
Camps & other closed communities.
At-risk communities during epidemics & outbreaks.
Travelers to endemic areas & pilgrims.
• Case-finding - Notification: LHO. - Isolation
• Disinfection - TTT - Release
• Food handlers “pre-employment”
• Chronic gall-bladder carrier
• Family & Household contacts
• Nursing personnel
• Sanitary measures - Heath education
• Epidemiologic study
3 -ve cultures of stools & urine, 24 or more hours apart.
1st sample: 2 weeks after drop of temperature to normal (to
exclude possibility of relapse).
• Diagnosis especially among food handlers & during pre-
Widal test for Vi antigen, if +ve: stool & urine culture can be
done (repeated cultures are indicated).
• For chronic gall-bladder carrier:
Ampicillin for 1-3 Ms until 3-ve successive samples.
cholecystectomy is indicated.
• For chronic urinary carrier:
Foci surgical removal.
Enlistment & Active immunization:
Mainly during seasonal spread or
Surveillance for 2 weeks, from
date of last exposure to the case.
Food handlers: excluded from work &
bacteriologically examined until prove
not to be carriers.
Precautions on nursing & not
to handle or serve food to the
Brucella organisms are relatively resistant in the environment.
Boiling of milk
Endemic in Egypt even with increasing incidence because of
animals' importation from different countries.
IP: varies, usually 6-60 days.
Case fatality of untreated cases is 2% or less & usually
results from endocarditis
Fever of unknown
ID hypersensitivity test (survey studies).
Milk & Meat
Sanitary disposal of
Increased bowel motions
than usual own pattern
Passage of ≥3 abnormal
loose stools that may
be associated with
fever, vomiting &
change in color &
presence of blood, pus
Etiology: infective & no infective.
2-Infectious food poisoning
3-Infective diarrheal disease of children (GE)
The organisms liberate potent exotoxins (enterotoxins). That
remain in intestine causing destruction of mucosa.
Current 7th pandemic: O1 sero-groups El-Tor biotype.
• V. cholera O1 & O139 can persist in water for long periods &
multiply in moist leftover food.
• Killed within 30 min. by heating at 56 C & within few seconds by boiling.
• Less resistant
• More virulent
• More severe
• More resistant
• Less virulent
• Mild cases,
• High carrier rate
Reservoir: Man is the only source of infection either case or
1-Cases: inapparent, subclinical or clinical.
2-Carriers: incubatory, contact & convalescent. Usually
temporary but in El-Tor biotype tend to be more chronic.
Exit: Stool & vomitus of cases. Stool of carriers.
1. Ingestion of contaminated water or food.
2. Beverages prepared with contaminated water, ice & even
commercial bottled water have been incriminated
• All ages are affected
• Attack rate is highest among childrenAGE
• Both sexes are affected.SEX
• Significant ↑ during summer & autumnSEASON
• Infection either clinical or sub clinical gives type
• Most cases: Asymptomatic or mild diarrhea, especially with El-Tor.
• Profuse painless watery stool (rice water stool).
• Nausea & profuse vomiting early in the course of illness.
Case-Fatality is high
But greatly ↓ (<1%)
due to better
• Heat killed phenol preserved
• 2 Doses (0.5&1 ml) 4 wks apart-
booster every 6 ms.
• Partial protection (50% efficacy)
• Short duration (3-6 months)
• Only antibacterial & not antitoxic
• Not prevent asymptomatic
infection & carrier state.
• Associated with adverse effect .
• Not recommended by WHO
• Significant protection for
• One is a single dose live
• Other is a killed vaccine
consisting of in-activated
vibrios + B-subunit of the
cholera toxic, given on a 2-
• 500 mg/6
hours for 3
• Single dose
• ½ dose for
of 300 mg
for 3 days
1- Notification to WHO.
2-Chemoprophylaxis: Tetracycline or Doxycycline
for travelers coming from endemic or infected
Vaccination certificate is not required
internationally since the vaccine is not
Early case finding and confirm diagnosis.
Report to LHO & WHO.
Isolation in fever hospital, quarantine or cordon.
Disinfection: Concurrent disinfection of all soiled articles
& fomites, stool and vomitus using heat & carbolic acid.
Terminal cleaning is sufficient.
Treatment: Adequate dehydration therapy using OR in mild
cases, IV rehydration in severe cases. Treatment of
Release after 3-ve successive stool sample.
• Enlistment by age, sex, occupation and residence.
• Isolation for 5 days calculated from the day of exposure.
• Release after 3 -ve successive stool sample.
• Education, Case finding & repeated stool culture to prevent
Of the public & population at risk about mode of transmission
and preventive measures:
• Ensure safe water supply and chlorination
• Provide appropriate safe sewage disposal
• Control of house flies.
• Ensure sanitary preparation & supervision of food & drinks.
• Investigate the situation to find the epidemic variables (TPP).
• Presence of bacteria or
other microbes which infect
body after consumption.
• Shigella spp.
• Camplobacter jejuni.
• Yarsinia enterocolitis.
• Ingestion of toxins
contained within food,
• Staphylococcus aureus.
• Clostridium botulinum.
• Clostridium perfringens.
• Bacillus cereus.
- Sporadic cases
Exotoxin of Cl .
- Man: Cases
of cattle, pigs&
- Man :Case or
carrier(skin or resp.
infec) >5% of
population having foci
of skin or nose
- Ingestion of food from
infected cattle or swine.
-Ingestion of food
excreta of animals or
- Water polluted with
excreta of man or
- Hand to mouth
Ingestion of food
packed or canned meats
or sausages or fish)
*packing of salted raw
Ingestion of enterotoxin
contaminated food or
milk by resp. discharge
of food handlers
Favored by: much
handling& sufficient time
& consumption without
38 hs12-36 hs2-6 hsI
Paralysis of occulo-motor &
other cranial ns causing visual
disturbances as diplopia, loss
of accommodation, dysphagia,
dysphonia & resp. paralysis
case-fatality is high (70%) in
few days due to resp. failure
Abrupt onset of GE
(for hours then
- Slight or no fever
- Case-fatality is
- Mainly Clinically
- Culture: Stool, Vomitus& Food remains (-ve results not exclude staph. as
organism may be destroyed while the enterotoxin is not).
General preventive measures of food borne diseases
In case of botulism:
1.Proper processing, packing, canning of food after sterilization
2. Food preservation at home
3. Suspected canned food to be spoiled (bulged from gas formation)
4. Specific prevention: Trivalent Botulism antitoxin
As food borne infection & investigation of outbreak
1. Sero-therapy by Trivalent Botulism antitoxin :limited value
(irreversible effect of exotoxin on CNS)
2.Seroprophylaxis for person sharing food with diagnosed cases but
3. Food remnants: destroyed after sampling for bacteriological
(Cl.Perfrinqens type A)
Anerobic spore forming
Aerobic spore forming 2
enterotoxins “heat labile (diarrhea)
& heat stable (vomiting)”.
Animals (cattle, poultry &fish)
Man (cases &carriers).
Spores found in the soil “rice”.Reservoi
Ingestion of spore-contaminated
Ingestion of spore-contaminated
6-24 hours.1-6 hours in emetic
6-24 hours in diarrheal cases.
- Intensive diarrhea, no vomiting
- Necrotizing enteritis “highly fatal
in the elderly”
GIT manifestations either Emetic or
Incubation period < 6 hours
Lasts 1-6 hours
Incubation period > 6 hours
Lasts 6-24 hours
EMETIC FORM DIARRHEAL FORM
Measures for cases:
Enlistment & distribution of cases by TPP.
Proper history taking & examination.
Culture of faeces & vomitus of cases.
Look for other cases.
Attack rate for food items eaten =
no. of cases among those ate certain food x100
all who ate the same food
Food items: Greatest difference in attack rates between
those ate this food and did not eat
Measures for food items:
1. Food handlers examination e.g. staph. infection:
nose & throat swabbing for carriers & skin & nails
2. Other sources of contamination e.g. rodents & their
Diarrheal Disease Of Children
Gastro-enteritis is diarrheal disease of
children below 5 years (infants & young
Reservoirs of Infection:
1- Man (cases or carrier)
2- Animals: non-typhoidal Salmonellae, Campylobacter jejuni, E.Histolitica,
Lack of effective
infection “chronic otitis
media & bronchitis”.
Sporadic cases all the
Monthly distribution of
cases in developing
countries shows 2
peaks: A high peak in
summer & fall.
A small peak, during
of acute respiratory
Epidemic diarrhea of
the newborn “E-coli”
Rapid multiplication of
organisms in milk &
secretion of stomach
infection, specially the
respiratory & urinary
IP: Vary according to the causative agents usually hours to 2-4 days.
Moderate & Severe cases
Abrupt onset, fever (usually high), frequent liquid or rice-water stools (≥20/day), vomiting
Mild diarrhea (>5 times/day), No or mild fever, No vomiting, No or insignificant
dehydration, and No or mild systemic manifestations (self-limited & clears up within days)
• Efficient health services
• Health education for
Management of case
• Mild: outpatient service
“Started under medical
supervision &Continue at
• Sever: Hospitalization.
1st line to replace loss of fluid & electrolytes & restores fluid-electrolyte balance.
a) Oral Rehydration Therapy (ORT): 5.5gm of NaCl, NaHCO (correct acidosis), KCl
(correct hypokalaemia) & glucose. Dissolved in 200 ml water.
b) Nasogastric Rehydration: repeated uncontrolled vomiting.
c) IV fluid Rehydration: hospitalized severe cases
- Cases having no dehydration: usual feeding & sufficient fluid & Supplementary vit.
- Cases with dehydration:
Mild cases: ORS & milk, alternating, until cured.
Moderate cases: initially given rehydration, with fasting (water if necessary) for some
hours until dehydration improves, then milk, then other foods can be given.
Inflammation of the colon (large intestine).
stools “Bl. &
Acute infectious inflammatory bacterial disease of the colon.
Worldwide disease. Usually sporadic cases. Outbreaks
occasionally in confined groups.
Incidence is higher with seasonal breeding of flies (spring,
early summer & fall).
Relatively resistant outside the
body, but readily destroyed by
heat & disinfectants.
Locally: the exotoxin is
enterotoxic, causing dysentery.
Toxaemia: exotoxin is a
neurotoxin, may be fatal
More than 1 attack may occur, due to different groups & serotypes.
Infection is usually followed by type-specific immunity.
• Reservoir of Infection: Man “cases & carriers”.
• Carriers: number is several times cases & forms the main reservoir of infection.
They are contact, healthy & convalescent carriers.
• Exit: faeces
• Infectivity: usually for few weeks, sometimes longer, and rarely for one or more years.
IP: 1 -7 days (usually less than 4).
Mild disease that may pass unnoticed.
• Sudden onset
• Vomiting & dysentery “May be”
• Usually self-limited
• Recovery in few days.
Severe fulminate disease
• Systemic manifestations
• Dehydration & complications
(uncommon) due to exotoxin
• Fatal (May be in young, elderly &
Dysentery: tenesmus, squeezing pain of lower abdomen & frequent
loose scanty stools, mainly made of fresh blood, pus & mucus.
Amoebiasis Giardiasis Balantidiasi
Entamoeba Histolytica “Endemic in
Egypt & many parts of the world”
Quadri-nucleate cyst “Resistant
outside body, but destroyed by heat,
desiccation & UVR”.
Cyst: passed with faeces
“remain viable in the
environment for months”.
Reservoir Man: chronic cases, or asymptomatic
cyst-passers. “Acute cases: non-
infectious, as they pass the fragile
vegetative form that perishes rapidly.
Even if ingested, it is destroyed by
gastric acidity & digestive enzymes”.
Man & mammals
(e.g. dogs, cats,
Man & Swine
Mode of 1. Food borne infection: ingestion of food or water contaminated
IP 3-4 weeks 1-2 weeks 3-4 days
C/P “Colon, with invasion of intestinal
1ry amoebiasis “Dysentery”:
2ry amoebiasis: other parts of
-Intestinal: severe ulceration
“may cause perforation of colon
& intestinal hemorrhage” and
abscesses, especially in the liver,
causing amoebic hepatitis
“Duodenum & Ilium,
without invasion of
-Gastro-enteritis of infants
ileum & Colon”
Ascaris Enterobius vermicularis Hymenolepis nana
Ascaris Lumbricoides “Ascariasis” “Oxyuriasis pinworm
Disease” most widespread
Prevalence Worldwide distribution “Preschool & school children are frequently, and may be heavily, infected
Embryonated egg “resistant to
desiccation & disinfectants, and remains
viable & infective, under favorable
environmental conditions, for 3
How Ascaris eggs reach food?
-Using fresh human fertilizer.
-Flies may have potential, least role.
Egg, deposited by migrating
gravid female worm in the
Eggs are relatively resistant
outside the body
Eggs passed in faeces, are
Reservoir Man Man & Rats “occasionally’
Ascaris Enterobius vermicularis Hymenolepis nanaModeoftransmission
Food borne Infection. Hand-to-mouth infection
No Auto-infection: eggs in
faeces are not infective,
except after developing into
embryonated egg “infected
food handlers do not spread
-Auto-infection: fingers &
nails contaminated with eggs
on scratching the anal region.
-Hands contaminated with
* Playing with the case.
* Handling soiled fomites.
*Touching soiled toilet
-Hand contaminated with
eggs when playing in rat
Internal Autoinfection: ova
invade the intestinal wall.
ASCARIS ENTEROBIASIS HYMENOLEPIS NANA
IP 2 months 1-2 months 2-4 weeks
C/P -Mild infection may be in apparent.
-Abdominal discomfort & colic.
-Restless sleep & grinding of teeth.
Perianal pruritus &
disturbed sleep and
Asymptomatic, mild or
abdominal pain &diarrhea
Stools examination: eggs. -Worms in anal region &
-Perianal swab to
demonstrate eggs (using
-Stool examination: not
Stools examination: eggs.
T.solium (pork tapeworm) & T.saginata (beef
Prevalence Worldwide. Man is usually infected with one worm only. Endemic in Egypt around Lakes Manzala
Cysticercus bovis in beef & Cysticercus cellulosa in
Encysted metacercaria in muscles of
infected brackish-water fish (e.g. Mugil
cephalus & Tilapia nilotica)
Reservoir Man: definitive host “discharges detached gravid
segments which rupture to liberate eggs in faeces”. Egg
is infective to the intermediate host (cattle for T.saginata
& pig for T. Solium) where it hatches in the intestine of
the animal & the embryo penetrates the intestinal wall
and then carried by the circulation to various tissues
(especially skeletal muscles where it becomes
Period of communicability so long the worm remains in
the intestine “sometimes >30 years”. T.saginata is not
directly transmitted from person to person.
Man: infected individuals pass eggs in
faeces. Fishermen in endemic areas are
particularly important for pollution of
brackish water channels where
intermediate hosts “Pyrenella conica” of
the parasite are found.
Fish-eating animals (e.g cats & dogs)
are potential reservoirs.
Man is infected by ingestion of raw or under cooked infected
beef or pork containing the infective stage. In the intestine
the scolex (in the cysticercus) evaginates, attaches to the
mucosa and develops into mature worm.
Ingestion of the infective stage in
muscles of infected brackish-water
fish when eaten raw, or
insufficiently cooked or grilled
(Salted raw Mugil fish "fessikh",
eaten before 10 days of pickling).
IP 2-3 months. 1-15 days
C/P -Asymptomatic “except annoyance from having segments of
worms emerging from the anus”.
-Nervousness, insomnia, anorexia, weight loss, however the
disease is non-fatal.
Chronic intermittent diarrhea, with
blood and mucus in stools,
abdominal discomfort and colicky
Diagnosis Stools examination: Gravid segment or eggs Stools examination: ova
Fasciola hepatica & less commonly F.
Echinococcus granulosus “Cystic echinococcosis”
Prevalence Worldwide especially in sheep or cattle
raising areas. “F.hepatica: Europe, America,
Australia &Middle East”,
“F.gigantica:common in Egypt”
Endemic in the Middle East and Arab North Africa
Encysted metacercaria on aquatic plants Echinococcus eggs
Reservoir Sheep (f. hepatica), cattle (f. Gigantica),
and other large herbivorous animals. The
infection is maintained in a cycle between
animals, water, snails and aquatic plants.
Man is an accidental host “no direct man to
Dog is the definitive host. “Pass Eeggs in faeces”.
Intermediate Host: Sheep, cattle&other
herbivorous animals. They ingest egg-
contaminated food, to form hydatid cysts in
different organs, specially lung and liver. Dogs
infected on ingesting hydatid cyst in animal organs.
Man:Occasionally infected with eggs from dogs.
Food-borne infection: Eating uncooked aquatic
plants such as water cress bearing encysted
Hand-to-mouth infection: usual method of infection,
when the hand gets contaminated with eggs, from
contact and playing with infected dogs.
Food-borne infection: ingestion of food or water
contaminated with excreta of infected dogs
- During liver invasion: Right upper quadrant
pain, hepatomegaly, liver function abnormalities
-After migration to biliary ducts: biliary colic or
No specific picture, but manifestations of slowly
growing tumor, according to location of hydatid cyst.
Viable eggs in faeces or in bile aspirated from
the duodenum “detection of non-viable eggs in
faeces occurs after eating liver from infected
* Clinical examination & X-ray: nonspecific cystic
tumor “not diagnostic, but suggestive”.
* Biopsy or aspiration of cyst: is avoided, for the risk
of anaphylaxis and secondary infection.
* Casoni test “intradermal hypersensitivity test”.