Acute Typhoid Fever ◊

 

Literature Recommendations

Exclusion-Case in SOS*
(Symptomatic)

Yes ◊[1,2,3,4,5,9,11]
Grade III-A

Exclusion-Case in SOS*
(Asymptomatic or previously symptomatic but now recovered)

Yes ◊ [1, 2, 3a, 11, 14, 23]
Grade III-A

Clearance-Case in SOS*

Yes [1, 2, 3a, 4, 8, 9, 11, 14, 23]
Three negative stools, 1 week to 1 month apart for clearance
except for food handlers. See preventive measure #3 and #4.
Grade III-A

Exclusion of Contact
(Symptomatic)

Yes ◊ [1, 2, 3a, 5, 23]
Grade III-A

Exclusion of Contact
(Asymptomatic)

Yes ◊ [1-{preventive measure #5}, 14, 23]
Grade III-B

Exclusion-Case in Children
(Group setting with children ≤ 5 years of age)
(Symptomatic)

Yes [2, 3, 8, 9, 23]
Grade III-A

Exclusion-Case in Children
(Group setting with children ≤ 5 years of age)
(Asymptomatic or previously symptomatic but now recovered)

Yes [8, 9a, 23]
See b below. The majority of sources require clearance with three
negative stools prior to return, regardless of symptoms in an
infected individual.
Grade III-A

◊ Applicable Code

CCR 2628
* SOS (Sensitive Occupations or Situations) is not defined precisely in either the Code of Regulations or Health & Safety Code. See Attachment 2 for the definition of food workers.
◊ See California Code of Regulations, Attachment 1, for details.
+ Local health departments may elect to follow more restrictive exclusion and clearance criteria

a Sources indicate to culture contacts and exclude if culture positive.
b One source suggests only two negative stools (see preventive measure #2) be required prior to returning a child who was symptomatic and is now asymptomatic to the day care setting. The majority of sources state three negative stools required for clearance (see Preventive measures 1, 7, 11).

Disease Trends in the U.S.:

In 2000 there was an outbreak of domestically acquired typhoid fever that involved seven people. The source of this outbreak was an immigrant employee who worked at the implicated restaurant (19).

According to Olsen et al (2003), there were a total of 60 outbreaks of S. Typhi from 1960-1999. In fifty-four outbreaks the exposure occurred inside the U.S. and caused a total of 957 cases (15). An asymptomatic carrier was the cause in 21 of the 60 outbreaks and in 16 of them food preparation had been provided by the asymptomatic carriers (15). Each year the CDC receives approximately 250 (can be as high as 445) reported cases, most of which are acquired outside the US (15, 16).

According to Mermin et al. (1998), from 1985 to 1994 there were 4408 cases recorded in MMWR; the most sizable outbreak during this time frame was due to a carrier who worked as a food handler. He contaminated orange juice causing 47 culture confirmed cases (17).

In 1986 an asymptomatic food handler was implicated in an outbreak of 10 cases in Maryland. She had emigrated to the U.S. from an endemic area. No secondary transmission occurred from the 10 cases to their household contacts (21).

Organism: Typhoid fever is caused by the bacterium Salmonella enterica, subspecies enterica, serovar Typhi that belongs to the family Enterobacteriaciae. It is spread primarily through contaminated food and water (1, 6, 18). It can produce a mild febrile illness or a severe clinical disease (1, 11). If a person is employed in a setting where they handle food or care for small children, they may be barred legally from going back to work until it has been determined that they no longer carry any typhoid bacteria. (10)

Reservoir of infection: Humans are the only natural host and reservoir (11). S. Typhi can be found in the GI tract, including the gallbladder and bloodstream of infected humans.

Modes of transmission: Fecal-oral route via person-to-person, contaminated food, contaminated water, contaminated fresh fruits and vegetables fertilized with night soil and eaten raw, contaminated shellfish from sewage contaminated areas (1, 7, 9).

Attack rates: The total number of organisms taken in and the vehicle that they are ingested in will influence the attack rate and the incubation period (11). From 1960-1999 the attack rate in reported outbreaks the U.S. was 23% (15).

Infectious dose: ID 50 is 100000 or 10000000 organisms (7) and some sources place it as low as 1000 organisms (18). Volunteers were given various doses of S. Typhi in 45 ml of skim milk and in those who ingested 1000000000 and 100000000 pathogenic S. Typhi, clinical infection occurred in 98% and 89% respectively. A dose of 100000 caused typhoid fever in 28% to 55% of volunteers, but a dose of 1000 caused none of 14 persons to become clinically ill (11).

Incubation Period – depends on host factors and size of inoculum: can be 3-60 days, with the normal range being 5-14 days (1, 7, 9, 15, 18).

Infectious Period: is 2-6 weeks (7). Ten percent of untreated typhoid patients shed bacilli for at least 3 months after onset of symptoms and 2-5% become carriers (1, 11, 18).

Diagnosis: The diagnosis of typhoid fever depends upon the isolation of S. Typhi from one of the following sources: stool, urine, bone marrow or a specific anatomical lesion (9, 11). Organism can be isolated from blood cultures and are positive in 60-80% of typhoid patients (18). Stool cultures can be performed but are positive in only about 30% of acute typhoid patients. Sensitivity increases with amount of feces cultured and increasing length of illness (15, 18). Fresh stool specimens are preferred over rectal swabs (1, 11). Blood culture is a diagnostic mainstay for typhoid fever (1, 11, 13) however, results depend on several factors: blood volume, method of culture, and prior use of antibiotics by patients (11, 13). Bone marrow culture provides the gold standard for diagnosis of typhoid fever especially in patients who have already received antibiotics (1, 11).

Preventive Measures
Exclusions:

  1. According to a joint collaborative project of The American Academy of Pediatrics, American Public Health Association & National Resource Center for Health and Safety (2002), in child care settings, caregivers with “diarrhea defined as three or more stools in 24 hr or blood in stool shall be excluded from childcare. Exclusion for acute diarrhea shall continue until diarrhea stops or stools are deemed non-infectious by appropriate health official. Children who develop diarrhea should be isolated from other children pending arrival of parent who should remove them from the facility. Children and caregivers who excrete intestinal pathogens but no longer have diarrhea generally may be allowed to return once diarrhea stops, except in those with Shigella, E. Coli O157:H7 or Salmonella Typhi. In the case of S. Typhi, three negative stool cultures are required before return to school setting (2- Guidelines and Consensus Document).” {Grade III-A}
  2. According to the American Academy of Pediatrics (2005), “Temporary exclusion is recommended when a child has diarrhea: defined as more watery stools, decreased form of stool that is not associated with dietary changes and increased frequency of passing stool that is not contained by the child’s ability to use the toilet. Exclusion until diarrhea resolves, except in the case of Toxin producing E. coli or Shigella which require two negative stool cultures after resolution and S. Typhi requiring three negative stool cultures and clearance from health professional or health department(8- Guidelines and Consensus Document).” {Grade III-A}
  3. According to the Public Health Laboratory Service (2004), “for clearance, negative fecal cultures are required for clearance (6 consecutive cultures for those whose work involves preparing or serving unwrapped foods not subject to further heating and three consecutive stools for all other SOS. Each stool must be obtained one week apart starting three weeks after treatment is completed (in cases, carriers and excreters). For contacts to a case two negative stools 48 hours apart after a case has commenced treatment (3- Guidelines and Consensus Document).” An excreter is defined as an individual who has no symptoms but sheds the organism in their stool or urine for less than 12 months. This individual may have been an asymptomatic case or a case that symptoms have resolved in (3). {Grade III-A}
  4. According to Heymann (2004), “typhoid carriers should be excluded from food handling and from patient care. They should not be released from restriction from occupation until local or state regulations are met. This often is a requirement of three consecutive negative stools cultures (and urine cultures in areas endemic for schistosomiasis) at least one month apart and at least 48 hours after therapy has stopped (1- Guidelines and Consensus Document).” {Grade III-A}
  5. According to Heymann (2004), “household contacts should not be employed in SOS until two consecutive negative stool & urine cultures taken 24 hours apart have been obtained (1- Guidelines and Consensus Document).” {Grade III-A}
  6. According to the Public Health Laboratory Service (2004), “stool specimen for culture should be collected for all contacts to a case and from anyone assessed to have had similar exposure to the case in the month preceding the onset of disease in the case (3 Guidelines and Consensus Document).” {Grade III-A}
  7. According to Stephens (2002), “when a child or staff member of an out of home child care setting is identified to be infected with S. Typhi he/she should be excluded from attending until three consecutive stool cultures are negative. Specimens from all other attendees and staff should be cultured and if positive, exclude until three consecutive negative results post treatment (9- Evidence Based Literature). {Grade III-A}
  8. According to Cruickshank (1990), “a food handler who is symptomatically ill with a gastrointestinal illness presents a real hazard and should be excluded from work. …with S. Typhiand S. Paratyphi there has been clear evidence that excreters without symptoms have been responsible for transmitting infection through food to other people. (14 Evidence Based Literature).” {Grade III-B}
  9. According to Richardson et al. (2001). “Our guidelines differ on bacterial gastrointestinal infections, such as salmonellosis, shigellosis, typhoid and paratyphoid. Some authorities suggest children should be excluded from school until negative stool samples are obtained. We could find no evidence to support this practice and suggest that these schoolchildren should be excluded only while they have diarrhea. For children younger than 5 years old child should be excluded from school setting until a negative stool culture is obtained. Those who are older than 5 years old they recommend to return them to school setting 24 hours after first normal stool (20 Evidence based reviews with guidelines formed out of reviewed literary sources).” {Grade III-A}
  10. According to Bolyard et al. (1998), “Restriction from patient care and the patient’s environment, or food handling is indicated for personnel with diarrhea or acute gastrointestinal symptoms, regardless of the causative agent (22 pg. 308). Evidence based reviews with guidelines formed out of reviewed literary sources).” {Grade III-A}
  11. According to American Academy of Pediatrics in the Red Book (2006), “when S serotype Typhi infection is identified in a symptomatic child care attendee or staff member, stool cultures should be collected from other attendees and staff members, and all infected people should be excluded. The recommended length of exclusion varies with the infected person's age; for children younger than 5 years of age, three negative stool specimens are recommended for return. For people 5 years of age and older, 24 hours without a diarrheal stool is recommended before return to a group setting (23 Guidelines and Consensus Document).” {Grade III-A}

    12. References

      1. Heymann, D.L. ed. Control of Communicable Disease Manual, 18th edition.2004. American Public Health Association, Washington, DC. Pgs 139-141. Guidelines and Consensus Document
      2. APHA, AAP, & NRCHS. Exclusion and Inclusion of Ill Children in Child Care Facilities and Care of Ill Children in Child Care. National Health and Safety Performance Standards: Guidelines for Out-of-Home Child Care. Second Edition. 2002. A Joint Collaborative Project of The American Academy of Pediatrics Elk Grove Village, IL., The American Public Health Association Washington, D.C. & The National Resource Center for Health and Safety in Child Care, University of Colorado Health Sciences Center at Fitzsimons Campus Aurora, CO. Guidelines and Consensus Document
      3. Public Health Laboratory Service, Advisory Committee on Gastrointestinal infections. Preventing Person to Person Spread Following Gastrointestinal Infections: Guidelines for Public Health Physicians and Environmental Health officers. Communicable Disease and Public Health 2004; 7(4):362-384. Guidelines and Consensus Document
      4. Communicable Disease Report Review. The Prevention of Human Transmission of Gastrointestinal infection, infestations, and bacterial infestations. A Guide for Public Health Physicians and Environmental Health officers in England and Wales 1995; Volume 5 Number 11: R158-172. Guidelines and Consensus Document
      5. Guerrant RL, Van Gilder T, Steiner TS, et al. Practice Guidelines for the Management of Infectious Diarrhea. Clinical Infectious Disease February 2001; 32:331-350. Evidence based reviews with guidelines formed out of reviewed literary sources
      6. Steinberg E B, Bishop R, Haber P, Et al. Typhoid Fever in Travelers: Who Should Be Targeted for Prevention? Clinical Infectious Diseases 2004; 39:186–91. Evidence Based Literature
      7. Musher, DM. & Musher, BL. Contagious Acute Gastrointestinal Infections. NEJM 2004; 351; 23:2417-27. Evidence Based Literature.
      8. American Academy of Pediatrics. Managing Infectious Diseases in Child Care and Schools: A Quick Reference Guide 2005 Aronson SS and Shope TR eds. Chapter 5. Accessed on 7/30/07 at www.aap.org. Gui Guidelines and Consensus Document
      9. Stephens I and Levine MM. Management of Typhoid Fever in Children. Pediatric Infectious disease Journal 2002; 21(2):157-159. Evidence Based Literature
      10. CDC. Disease information-Typhoid fever accessed on August 21, 2007 at http://www.cdc.gov/ncidod/dbmd/diseaseinfo/typhoidfever_g.htm#how. Guidelines and Consensus Document
      11. WHO. Background document: The diagnosis, treatment and prevention of typhoid fever. 2003 accessed on August 17, 2007 at http://www.who.int/vaccines-documents/DocsPDF03/www740.pdf. Evidence Based Literature
      12. Cote TR, Convery H, Robinson D, et al. Typhoid Fever in the Park: Epidemiology Of An Outbreak At A Cultural Interface. Journal of Community Health 1995; 20(6):451-458. Review of Outbreaks and Epidemiology
      13. Nizami SQ, Bhutta ZA, Siddiqui AA and Lubbad L. Enhanced detection Rate of Typhoid Fever in Children in a Slum in Karachi, Pakistan using Polymerase Chain Reaction Technology. Scandinavian Journal of Clinical laboratory Investigation 2006; 66:429-436. Evidence Based Literature
      14. Cruickshank JG. Food Handlers and Food Poisoning. BMJ 1990; 300(6917):207-208. Evidence Based Literature
      15. Edelman, R, Levine, M. Summary of an international workshop on typhoid fever. Rev Infect Dis 1986; 8:329. Evidence Based Literature
      16. Olsen SJ, Bleasdale SC, Mangano AR et al. Outbreaks of typhoid fever in the United States, 1960-1999. Epidemiology and Infection 2003; 130:13-21. Review of Outbreaks and Epidemiology
      17. Mermin JH, Townes JM, Gerber M. et al. Typhoid fever in the United States, 1985-1994. Archives of Internal Medicine 1998; 158:633-638. Review of Outbreaks and Epidemiology
      18. Perry CM, Hien TT, Dougan G, et al. Typhoid Fever. New England J Med 2002; 347(22):1770-1782. Evidence Based Literature
      19. Yoon J, Segal-Maurer S, and Rahal JJ. An Outbreak of Domestically Acquired typhoid fever in Queens, NY. Archives of Internal Medicine 2004; 164:565-567. Review of Outbreak and Epidemiology.
      20. Richardson M, Elliman D, Maguire H, et al. Evidence base of Incubation Periods, Periods of Infectiousness and Exclusion Policies for the Control of Communicable Diseases in Schools and Preschools. Pediatric Infectious disease Journal 2001; 20(4): 380-391. Evidence based reviews with guidelines formed out of reviewed literary sources
      21. Lin FC, Becke JM, Groves C, et al. Restaurant-Associated Outbreak of Typhoid Fever in Maryland: identification of Carrier Facilitated by Measure of Serum Vi Antibodies. Journal of Clinical Microbiology 1988; 26(6): 1194-1197. Review of Outbreak and Epidemiology.
      22. Bolyard EA, Tablan OC, Williams WW, et al. Guideline for Infection Control in Health Care Personnel, 1998. American Journal of Infection Control 1998; 26(3): 289-354. Evidence based reviews with guidelines formed out of reviewed literary sources
      23. American Academy of Pediatrics. Section 3 Summaries of Infectious Diseases Salmonella Infections In: Pickering LK, Baker CJ, Long SS, McMillan JA, eds. Red Book: 2006 Report of the Committee on Infectious Diseases. 27th ed. Elk Grove Village, IL: American Academy of Pediatrics; 2006: 579-584. Guideline and Consensus Document.