E coli

E.coli, infections/diseases due to E.coli and diagnosis

1. PRESENTED BY: NOMAN HAFEEZ KHOSA ABDUL SAMI FARHAN MISBAH SADIQ ANUM AJMAL Escherichia coli

2. 2 Esherichia coli Gram-negative rod Facultative anaerobe Named for Theodor Escherich German physician (ca. 1885) Demonstrated that particular strains were responsible for infant diarrhea and gastroenteritis Normal flora of the mouth and intestine Protects the intestinal tract from bacterial infection Assists in digestion Produces small amounts of vitamins B 12 and K Colonizes newborns GI tract within hours after birth There are more than 700 different serotypes of E . coli

3. Morphology usually motile, produce peritrichous flagella some produce polysaccharide capsules grow well on non-selective media, forming smooth, colourless colonies 2-3 mm in diameter in 18h on nutrient agar temperature ( 15-45 ℃ )

4. 4 Many strains O antigen Somatic 171 antigens H antigen Flagella 56 antigens K antigen Capsule and or fimbrial antigen 80 antigens O18ac:H7:K1 18 th O antigen 1 st K antigen 7 th H antigen

5. Diseases caused by E. coli E. coli is responsible for three types of infections in humans: urinary tract infections ( UTI ) , neonatal meningitis , intestinal diseases (gastroenteritis) .

6. 6 Neonatal Meningitis E. coli NMEC Meningitis in an infection of the fluid and membranes that cover the brain and spinal cord Bacteria Viruses Fungi E . coli incites between 1/4 and 1/3 of meningitis cases in newborns Less than 2% of cases of meningitis at all other ages Approximately 1 out of 5 newborns with E . coli meningitis dies Survivors frequently sustain permanent brain damage The majority of cases occur in premature babies K-1 80% of NMEC E. coli strains produce K-1 capsular antigens K1 capsular polysaccharide O18ac:H7:K1 Inhibits phagocytosis Siderophore production Sequesters Fe Endotoxin

7. 7 Enteric / diarrheal diseases E. coli can adhere to the mucosa of the large intestine

8. 8 Transmitted via food Ground beef Raw milk Lamb meat Venison jerky Salami and other fermented dried meat products Lettuce, spinach, alfalfa sprouts Unpasteurized apple cider Transmitted via water Drinking and swimming in unchlorinated water Direct person to person contact Diaper changing Improper sanitation Day care & chronic adult care facilities

9. 9 Identification MacConkey agar (SMAC) Does not ferment sorbitol rapidly Forms colorless colonies on sorbitol containing MacConkey agar Serology Colorless colonies on SMAC are screened for the 0157 antigen

10. Prevention in Humans Good hygiene Hand washing After livestock contact Before eating and drinking After changing diapers Separate contaminated clothing Isolate infected children?

11. Prevention in Humans Don’t cross-contaminate Wash hands, counters, cutting boards, utensils after contact with raw meat Thoroughly cook meats Avoid unpasteurized products Wash fruits/vegetables before eating Keep livestock away from private water supplies Center for Food Security and Public Health, Iowa State University, 2012

12. Treatment treatment is based on symptomatology. fluid replacement is the primary treatmen Antibiotics are generally not used except in severe disease or disease that has progressed to a systemic stage (e.g.hemolytic-uremia syndrome).