Enteric (Typhoid) Fever

Enteric (Typhoid) Fever: 

Enteric (Typhoid) Fever

PowerPoint Presentation: 

Typhoid fever Salmonella Typhoid fever is the results of systemic infection mainly by salmonella Typhi found only in man

PowerPoint Presentation: 

Typhoid fever , also known as "enteric fever" is a collective term that refers to typhoid and paratyphoid. it is a common in worldwide. Transmitted by the ingestion of contaminated food or water with Salmonella Typhi. The bacteria then perforate through the intestinal wall and are phagocytosed by macrophages.

PowerPoint Presentation: 

Coliform bacilli (enteric rods) Motile gram-negative facultative anaerobes Non-lactose fermenting Resistant to bile salts H 2 S producing The organism is motile due to its peritrichous flagella. General Characteristics of Salmonella

PowerPoint Presentation: 

This is a highly adapted, human-specific pathogen occurring more frequently in underdeveloped regions of the world where overcrowding and poor sanitation are prevalent. According to the best global estimates, there are at least 21 million new cases of typhoid fever each year, with 6,00,000 deaths (Ivanoff, 2004). Between 1 - 5% of patients with acute typhoid infection have been reported to become chronic carriers of the infection, depending on age , sex and treatment regimen. Furthermore this chronic carrier state has also been implicated in causation of carcinoma of the gall bladder . Epidemiology :

Antigenic structure of Salmonella: 

Antigenic structure of Salmonella Two sets of antigens present Somatic or 0 Antigens contain long chain polysaccharides ( LPS ) comprises of heat stable polysaccharide commonly. Flagellar or H Antigens are strongly immunogenic and induces rapid antibody formation. High titers following infection or immunization

Agent factors: 

Agent factors S. typhi and para typhi A & B Man is the only Reservoir of Infection Cases Carriers (convalescence, Incubatory and chronic) Source of infection Primary Feces and urine of cases and carriers Secondary contaminated water, food, fingers & flies

Host factors : 

Host factors Age – 5-19 years Sex – Males > Females Carriers Females > Males Immunity – all age groups are susceptible. Second attack may occur Environment:- July- Sept IP – 10 to 14 days Mainly by faecal - oral, urine-oral route

PowerPoint Presentation: 

Clinical Fetures of Salmonella Prodromal stage: malaise, headache, cough, sore throat abdominal pain and constipation fever ascends like step ladder pattern After 7- 10 days fever reaches plateau and looks toxic with pea soup diarrhoea, Nausea, vomiting, cramps, myalgia and headache. Spleenomegaly abdominal distention and tenderness Relative bradycardia, dicrotic pulse. Rose spots commonly appear in the second week

Diagnosis: 

Diagnosis Blood culture is usually positive in only half the cases. . Bone-marrow culture increases the diagnostic yield to about 80% of cases Stool culture is not usually positive during the acute phase of the disease WIDAL Test land Mark In Diagnosis: WIDAL Test land Mark In the Diagnosis typhoid fever. Widal test is an old serologic assay for detecting IgM and IgG antibodies to the O and H antigens of Salmonella . The test is unreliable, but is widely used in developing countries because of its low cost. Newer serologic assays are somewhat more sensitive and specific than the Widal test, but are infrequently available IDL Tubex test with in few mints can detect IgM09 Typhidot -3hrs IgM and IgG against 50 KD antigen

Control of typhoid fever: 

Control of typhoid fever Control of reservoir- cases and carriers Improve the sanitation Immunization

Control of reservoir: 

Control of reservoir Cases – Early diagnosis Notification Isolation – atleast three bacteriologically negative stools and urine Treatment Disinfection Follow up Carriers- identification Treatment Surgery Surveillance Health education

Immunization: 

Immunization It is not 100% protection but it decrease both incidence and seriousness of the infection Those living in endemic areas Household contacts Groups at risk such as school children and hospital staff Travelers proceeding to endemic areas Those attending melas and yatras

Vaccines: 

Vaccines Vi polysaccharide vaccine Sub unit vaccine Vi capsular polysaccharide from the Ty2 S. typhy No use for less than 2yrs old children Single dose SC or IM 25micrograms of Antigen Revaccination required once in every three years

Vaccines con..: 

Vaccines con.. Ty21a Vaccine Live attenuated Ty2 strain of S. typhi Oral administration Two forms Capsular used above 5 years age and liquid form used above 2 years Three doses – 1, 3, and 5 th days immunity develops after 7 days of last dose revaccination required once in every three years Can administer HIV positive, asymptomatic individuals (T cell count CD4 >200/mm3)