1. Salmonella species
Prof. Dr. Abbas Hayat

4. Non Lactose fermenters
Colorless colonies on Mac Conkeys
• Shigella species:  (diarrhea dysentery)
• Salmonella species:  ( enteric, typhoid fevers,
enterocolitis and septicemia)
• Proteus species wound infections, UTI's in
anatomically obstructed urinary tract otitis media,
surgical infections )
• Pseudomonas species: wound infections, UTI's
in anatomically obstructed urinary tract, otitis media,
surgical infections )

5. EWINGS CLASSIFICATION
• Salmonella typhi: TYPHOID
• Salmonella enteritidis: Gastroenteritis
• Salmonella Para typhi A,B,C 1800 serovars.
Para typhoid Fevers
• Salmonella cholerasuis: Septicemia

6. GENERAL CHARACTERISTICS
Gram-negative rods, Motile,
peritrichous flagella produce abundant
Hydrogen sulfide.
Surface antigens "O", "Vi", "H"
Phase variation seen in ("H" ) or
Flagellar antigen.
Endotoxin – Lipopolysaccharide,
Exotoxins & Enterotoxins

15. Pathogenesis of Salmenollosis

16. Scheme of Pathogenesis
Enterocolitis and Diahorrea

20. Epidemiology
• Non-typhoid Salmenollosis worldwide
disease of humans and animals.
• Animals main reservoir,
• Usually food borne,
• Spread `` Person to Person ``.
• Salmonellae that cause Typhoid fever and
other enteric fevers spread mainly by fecal-
oral route.
• Asymptomatic human carriers ("Typhoid
Mary’s") may spread the disease.
• Contaminated food: Major mode of
transmission for non-typhoid salmonellae,

25. W 1 Poster

27. Salmenollosis a zoonosis.
• Animal reservoirs : chickens, turkeys, pigs, and
cows; dozens of other domestic and wild animals
also harbor these organisms.
• Animal meat etc. not properly cooked are the main
vehicle of transmission.
• Reptile’s House hold lizard important reservoirs
in homes and hospitals.
S. typhmurium isolated from CHIP KALI`S of
Paeds ward H.F.H in 1987 unpublished data .
• Frozen eggs. ( Siachin outbreak Pak. Army)

28. DISEASES
A. Enteric Fever or Typhoid.
• S. typhi S. paratypi A B & C
• CLINICAL FINDINGS:
40 days illness.` BARRA BUKHAR`
• Temp. Increases in step ladder fashion.
• High grade fever with constipation
• Rose spots, high fever, enlarged Spleen,
Abdominal tenderness by end of first week.
• Intestinal Hemorrhage or perforation leading to
peritonitis can occur by third week.
• Untreated patient dies in 40 days or so, or
recovers.
Salmonella is the most common causative
organism in Sickle cell disease > 80 %.

29. • Rose spots in Typhoid Fever

30. LAB. DIAGNOSIS
Specimen Collection:
• BLOOD CULTURE. 90 % isolation in first
week, Bone Marrow culture 100% in First
week .
• Adults 8 ml to 10 ml. Children 3 ml to 4
ml.
• METHOD: Site of Venupuncture swabbed
with 70% Alcohol and 1% Iodine for 03
minutes.
• 5-10 cc blood collected in Syringe is
injected through the stopper aseptically in
Blood culture bottle with 50 ml. of BHI (Brain
Heart infusion).

31. • Incubated for 07 days at 37 o C. Subculture on
Mac Conkeys medium when turbidity appears or
after 3 days to look for. Non Lactose fermenting
colorless colonies.
• Presumptive identification by T.S.I. medium
ALKALINE SLANT ACID BUTT With GAS AND H2S.
• Final identification by specific antiserum.
• Apply Sensitivity and report organism. With
sensitivity results to commonly used antibiotics.

32. Salmonella enteritidis (serotype typhimurium) can
ferment glucose but not lactose as carbon source and
produces both hydrogen sulfide and gas.

33. WIDAL TEST: 2nd week onwards,
• 3 cc clotted blood is taken serum separated.
Antibodies in patient’s serum against O, H,
and Vi (virulence antibody) are looked for by
an agglutination reaction known as WIDAL
TEST.
• ANTIGENS USED ARE: TO, TH.
AO, AH. BO, BH.
• Serial dilution in 07 test tubes are made of
the patients serum: and mixed with antigen to
look for agglutination reaction

34. Patient
serum
1:20 1:40 1:80 1:160 1:320
Antigen
TO
- - - ++ ++
TH _ _ _ _ ++
AO _ _ _ _ _
AH _ _ _ _ _
BO _ _ _ _ _
BH _ _ _ _ _

35. Interpretation of Widal test:
Titer : reciprocal of the dilution.
• A significant titer is a titer => 1:160 or a
rising titer.
• Increase in O titer means active infection.
• Increase in H titer means Past infection or
vaccination.
• In tropical countries H titer arises earlier
than the O titer.
• Vi antibody is present in carriers.

36. Faeces & Urine Culture: In 2nd and 3rd week
Culture on Mac Conkeys medium,
use Enrichment medium like tetraethionite broth
or a
Selective medium like Salmonella Shigella agar.
Isolate organism and report sensitivity.
I_______2______3________4_______weeks
,________ Blood
________________________ ______ widal
_____________________________
urine and feces.
• OTHER TESTS: TYPHIDOT Ig G and Ig
M are looked for.

37. Treatment: Ampicillin/ Amoxil ,
Chloramphenicol , Trimethoprim-
Sulfamethoxazole
• Quinolones like Ofloxacin
Ciprofloxacin ceftizadime, cefspspan
etc. Preferred
• Treatment required for at least 10
days to prevent relapse.
• Response gradual ~3 to 4 weeks with
Ampicillin 4 gm daily may be required
•Chronic Carriers may
require gall bladder removal

38. • Resistant to Sulphamethaxazole-
Trimethoprim
Ampicillin/Amoxil and
Chlorophenicol first reported from
Pakistan in 1989 from this
department.
• Drug of choice became Quinolones
like Ofloxacin, cannot be safely
used in children for reports of
cartilage damage so I.V Clafron or
Rosephin had to be given.

39. Non typhi Salmonellae (N.T.S)
Bacteraemia, resistant salmonella
strains in Rawalpindi
Balouch AH, Akhtar MJ and Karamat
KA/ Rawal Med J 1989; 17:AFIP,
Rawalpindi
2. Multiple Drug Resistant
Salmonella Typhi in Northern
Pakistan. Pakistan Journal of
Pathology vol. 2. No. 1 Jan-June 1991. Abbas et al

40. B. GASTROENTERITIS.
• Salmonella enteritidis 1,500 serotypes
• Poultry, Meat, Dairy Products
• Contaminated food > 1000 organisms/ml.
• Acid-killed
• Some penetration of intestinal mucosa
• Enterotoxin (Similar to E. coli LT toxin)
• Diarrhea and inflammation of intestinal
wall
• Occasional septicemia

41. Investigation of Outbreaks
• Food and Water Samples
• Human carriers esp. Food handlers in
kitchens of canteens , hostels, hotels and
food caterers.
• Specimens of food, water or ice
cream are tested, if considered to be
implicated in outbreak.

42. Treatment of Gastrenertis caused by
Salmonells species.
• Fluid replacement.
• Antibiotics not effective rather
eradicate protective normal flora
leading to overgrowth of resistant
and pathogenic bacteria.
• Probiotics ( Healthy bacteria)
promising results, recent findings.

43. C. Septicemia
• Salmonella cholerasuis
• Diagnosis: Blood Cultures.
• Treatment: Same as for Typhoid
fever.

44. VACCINATION
• Vaccines are available for typhoid fever
and are partially effective, especially in
children.
• Initially TAB Acetone killed vaccine Now
oral live attenuated vaccine by brand
name VIVOTIF
• 4 tabs on alternate days. Protect for 2-3
years.
Rx: Advised for all of you and family members.

45. 19th century epidemic of typhoid
fever

46. PREVENTION AND CONTROL.
• Public Health and Personal Hygiene.
• Proper Sewage treatment and Chlorination of
water supplies.
• Salmonellae are difficult to eradicate from the
environment. .
• Major reservoir for human infection is poultry and
livestock.
• Animal feed treated with Antibiotics.
• .Providing training in hygienic practices for all
food-handlers and their routine screening.
•"Boil it, cook it, peel it,
or forget it"

48. Spread

50. Fever pattern of Typhoid
Feverpattern of Brucellosis

51. Fever pattern of Brucellosis

52. Pattern of Fever in malaria

53. Person to person spread esp. in
children is very common

54. Thanks