Typhoid Fever

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Typhoid Fever

• Reportable Diseases
• Surveillance Investigation
• Louisville Metro Health Department
• Louisville, Kentucky, 40202

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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

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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

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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

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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

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• 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

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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

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Interviews conducted

• We conducted interviews to collect information
  regarding
• clinical data
• demographic information
• complications and treatment
• epidemiological information

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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)

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Patient 1

• 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

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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

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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

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Restaurant A (Employer of Patient 2)

• Upon being notified of Pt. 2s 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

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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 As
  corporate office that all employees in Pt. 2s
  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.

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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

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Clinic Planned at Restaurant B.

• Arrangements made for LMHD to arrive at
  Restaurant B. in the early morning in order to
  finish prior to restaurants opening for lunch at
  1100 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

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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

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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

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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 EDs to
  encourage increased index of suspicion for
  typhoid in patients with fever of unknown origin
  and rigors with or without GI symptoms

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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

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Investigation Results

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

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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
  daughters 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

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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.