TYPHOID FEVER

MADE BY SANA AJMAL

TYPHOID FEVER

• SALMONELLA TYPHOID• It is due to INTESTINAL infection, characterized by

continuous fever for 3-4 weeks with bradycardia and involvement of lymphoid tissues.

• Disease occurs sporadically, endemically and epidemically in humans.

EPIDEMIOLOGY• July to September• Occurs in overcrowded and poor sanitary places.• All ages are equally affected but peak occurrence is at 5 to 19 years.DETERMINANTS

• PRIMARY: Salmonella typhi• Salmonella paratyohi A&B• S.typhi is the major cause and it has three antigen

1. O ANTIGEN: somatic antigen2. H ANTIGEN: Flagella antigen3. Vi ANTIGEN: Virulence antigen and has 80 phage types for determining epidemic phage

• SECONDARY:RAINY SEASON, contaminated water supplies, open air defecation.

FREQUENCY• Occurs all over the world where poor water sanitation is present.• In Pakistan it is hyper-endemic.

SOURCE OF INFECTION OF TYPHOID FEVERPRIMARY SOURCES

SECONDARY SOURCES

Feces and urine of cases and carriers

Contaminated • Food• Water• Milk• Flies• finger

MODE OF TRANSMISSION• Feaco-oral route• Urine oral routeRESEVOIR OF INFECTION• Man is the only reservoir and may exist as a case or a

carrier INCUBATION PERIOD10 -14 days

CLINICAL FEATURES:• INVASIVE (1ST WEEK):

• Onset with pea soup diarrhea• Headache, body ache, anorexia• Raw coated tips and edges of tongue.• STEP LADDER FEVER: low in the morning and gradually gets high at night. It is worse at the start

of the week but gets better later on. • Bronchitis• Bradycardia• Constipation at the end of the week

• ADVANCED (2ND WEEK):if untreated case• Splenomegaly• Rose spots on the abdomen and back which disappear on pressure and ultimately heals after 3-4

days.• DECLINE (3RD WEEK):• Serious complication;

• MILD CASE: gradual fall in temperature• SEVERE CASE: increased toxemia, intestinal hemorrhage.

CONVALESCENCE:in uncomplicated cases the fever subsides in 4 weeks.

DIAGNOSIS• WBC count: leukopenia• Blood culture• Stool culture• Typhoid test• Felix-Widal test

(unknown antibody and known antigen)During 2nd and 3rd week of inf. Agglutinating antibodies rise. Serum is tested againt known antigen of representative Salmonella.Results:

• Titers of antibody against O antigen shows active infection (6-7days of inf.)• Titers of antibody against H antigen shows past immunization (10 to 12 days of inf.)• Titers of antibody against Vi antigen shows carriers.

• Other tests: IDL Tubex® Test , Typhidot® , Dipstick test

CONT

ROL CONTROL OF RESERVIOR

Case control:Chloramphenicol, cortimoxazole, amoxicillin

Carrier: ampicillin, probenecid+cholecystectomy

SANITATION CONTROLClean water preservation

Food hygieneHealth education

IMMUNIZATIONGiven at >1 year

Anti-typhoid vaccine:Monovalent( immunity against only 1 antigen

source)Divalent (immunity against both typhi,

paratyphi)TAB VACCINE (Typhi, paratyphiA&B)

DOSE: 2 doses 0.5ml every month subcutaneously

BOOSTER DOSE: after every 3 years

TREATMENT OF TYPHOID FEVER:• Chloramphenicol for 5-7 days• Low caloric diet with soups, vegetables, milk, eggs

and potatoes.• CIPROFLOXACIN is now drug of choice.

CARRIER PRESENCE OF DISEASE

TIME PERIOD

Convalescent carrier After onset of symptoms→50% pt. secrete S.typhi in feces.

3 weeks after onset

Healthy Carrier Clinically unrecognized disease

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Chronic Permanent Carrier

No typhoid fever at the time but still discharge S.typhi

After 12 months of post-infection

TYPES OF CARRIERS IN TYPHOID FEVER