1. Typhoid Fever Reportable Diseases Surveillance & Investigation
Louisville Metro Health Department
Louisville, Kentucky, 40202

2. Typhoid Fever Outbreak
On Monday, May 3,2004, a positive blood culture for Salmonella typhi in a 12 y.o. female was reported by a local hospital
Due to the uncommon occurrence of typhoid fever in the community an investigation was initiated to identify the source of infection as well as any activities associated with the spread of the infection
State Health Dept. notified. Sporadic cases occasionally occur and are not considered a cause for alarm unless additional cases are identified

3. Second Case Reported
On Tuesday, May 4, Salmonella (serotype unknown) cultured from the blood of a 39 yo male at a local hospital
Clinical presentation consistent with typhoid fever (fever 103, headache, mild diarrhea)
Newly employed as a manager-in-training at a local restaurant (Restaurant A)
Specimen sent to state lab for serotyping
Investigation started on the assumption that possible typhoid outbreak (2 or more cases associated by time and place) in progress

4. Clinical Manifestations of Salmonella typhi Disease (Typhoid fever)
Clinical course : a gradual onset of illness with fever, headache, malaise, anorexia, lethargy, abdominal pain, hepatomegaly, splenomegaly, and possibly a “rose spot” rash on the trunk or a nonproductive cough

5. Epidemiology of Typhoid Fever
Bacterial disease-Salmonella typhi
Humans are the only source of infection
Asymptomatic carrier state may follow illness, including subclinical infection
Occurrence
Estimated 17 million cases annually with approx. 600,000 deaths worldwide
Fewer than 500 cases annually in US
Fewer than 5 cases annually in Kentucky

6. Mode of Transmission Fecal-oral
By food and water contaminated by feces and urine of patients and carriers (shellfish, raw fruits and vegetables, milk products)
Incubation period 3 days-1 month with a usual range of 8-14 days

7. Salmonella typhi Case Definition
a case that meets the clinical case definition and is confirmed by isolation of S. typhi from blood, stool or other clinical specimens

8. Interviews conducted
We conducted interviews to collect information regarding:
clinical data
demographic information
complications and treatment
epidemiological information

9. Results of Epidemiologic Investigation
Cases were investigated thoroughly to assess risk factors for acquiring illness, similarities in activities and risk of spread to the community
Onset dates (4/18/04 and 4/12/04)
Occupation (1 student, 1 food handler)
Travel (both denied personal travel , but had recent contact with immigrants)
Restaurant patronage (1 facility identified by both patients- Restaurant B)

10. Patient 1 The interview process revealed:
An interview was conducted with the mother of the 13 yo female
The interview process revealed:
a recent history of aiding Somolian refugees re-settle through church program
Stool specimens were negative
Ate at Restaurant B every Friday night

11. Patient 1 (cont.) Attends a local middle school
LMHD issued an advisory to the school about Salmonella (did not specify type) and the importance of hand hygiene
A team of LMHD nurses visited the school to assess the hand washing facilities and procedures of the kitchen staff as well as the students and teaching staff

12. Patient 2 An interview was conducted with the 39 yo male
Interview process revealed
Employed as a manager-in-training at a local restaurant-Restaurant A. Notified the environmental health/food hygiene office of LMHD to notify employer of exclusion from work until released by LMHD
Many co-workers in restaurant are recent immigrants from Senegal
Identified Restaurant B as a frequent choice for dining

13. Restaurant A (Employer of Patient 2)
Upon being notified of Pt. 2’s exclusion from work due to illness, restaurant obtained a contract physician to evaluate risk to the business
Contract physician (Dr. C.) obtained a consent for release of information from Pt. 2, and obtained hospital record
Dr. C. felt clinical presentation consistent with typhoid fever. Inquired about testing all restaurant staff. Decision made by KDPH to wait until serotype confirmed

14. Second Case Confirmed
Contract physician for Restaurant A notified that their employee (Pt. 2) confirmed to have S. typhi
Dr. C. recommends (as does CDC) to Restaurant A’s corporate office that all employees in Pt. 2’s store be screened for typhoid
Dr. C. travels to Louisville to personally instruct restaurant staff on stool specimen collection and to instruct staff about hygiene and the importance of reporting any illness
Specimens are sent to a private lab for evaluation per choice of Restaurant A.

15. Restaurant B. Investigated
Owner of Restaurant B. contacted and advised that his facility was identified as the only link between two ill citizens (exact nature of illness not revealed to prevent information leak and public panic)
Requested he arrange for staff to be present for lab specimen collection to screen for the source of illness
Assured that no mention of the situation will be made to the press at this time

16. Clinic Planned at Restaurant B.
Arrangements made for LMHD to arrive at Restaurant B. in the early morning in order to finish prior to restaurant’s opening for lunch at 11:00 a.m.
Supplies and staff organized to collect blood specimens and to distribute stool specimen collection kits
Health history questionnaire developed to screen for symptoms of typhoid fever as well as travel history and work history for past 2 years
Translators acquired as most of the staff at Restaurant B. spoke little English

17. Results of Restaurant Investigations
Restaurant A: Total of 86 staff
55 voluntarily provided stool specimen
All specimens negative for S. typhi
Decision was made not to “require” staff to comply

18. Restaurant Results (Cont.)
Restaurant B: Total of 25 staff
22 presented at on site clinic for health history and blood specimen collection
Stool collection kits distributed with instructions
All specimens negative for typhoid Vi antibody
8 stool specimens returned- negative

19. Public Health Decisions
LMHD consulted KDPH throughout the course of the investigation
KDPH consulted CDC Enteric pathogens branch for advice about outbreak investigation
CDC recommended extensive histories on both patients as well as screening of employees at both restaurant facilities involved
Public Health Advisory issued to local ED’s to encourage increased index of suspicion for typhoid in patient’s with fever of unknown origin and rigors with or without GI symptoms

20. Laboratory Services
CDC made arrangement for serum of Restaurant B.’s employees to be tested for Typhoid Vi antibody at their lab, as well as PFGE testing of the cases’ specimens
KDPH made arrangements for stool specimens of Restaurant B.’s employees to be cultured at the state lab

21. Investigation Results
No source of infection for patients 1 or 2 was identified
No further cases of S. typhi reported

22. Lessons Learned
Use of Environmental Food Hygiene staff was beneficial due to established relationship with restaurant managers
Confidentiality was extremely difficult to maintain due to large number of people involved
Mom of patient 1 told several people her daughter’s diagnosis
A physician who is friend of mom informed her that he had seen another case of typhoid recently
Pt 2 discussed his diagnosis with others

23. Lessons (cont.)
Immigrant status of employees of Rest. B contributed to a fear of cooperating
Payment for laboratory services needs to be pre-arranged
100% management/employee cooperation necessary in order to identify carrier or exclude facility as a possible source
Although no source was found, attempt was necessary for public safety.