Cryptosporidium

	Literature Recommendations
Exclusion-Case in SOS* (Symptomatic)	Yes [1, 2, 3a, 4a, 5a, 6, 7, 8, 10, 17, 20] Grade II-A
Exclusion-Case in SOS* (Asymptomatic or previously symptomatic but now recovered)	No [1, 2, 3a, 4a, 17] Grade II-A
Clearance-Case in SOS*	Not required [1, 2, 3, 4, 9, 17] Grade II-A There is only one source that disagrees [5b]
Exclusion of Contact (Symptomatic)	Yes [1, 2, 3a, 4a, 5a, 8, 10, 17] Grade II-A
Exclusion of Contact (Asymptomatic)	No [1, 2, 3a, 4a, 17] Grade II-A
Exclusion-Case in Children (Group setting with children ≤ 5 years of age) (Symptomatic)	Yes [1, 2, 3a, 4a, 5, 9] Grade III-A
Exclusion-Case in Children (Group setting with children ≤ 5 years of age) (Asymptomatic or previously symptomatic but now recovered)	No [1, 2, 3a, 4a, 5c, 17c] Grade II-A
◊ Applicable Code	None
* 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 If person had diarrhea the recommendation is exclusion until after 48 hours from first normal stool.
b Recommending 2 normal stool samples: taken 24 hrs apart at least 48 hrs after first normal stool or last dose of therapy, for food handlers and health care workers. This however is a generalized statement by an article that is a review of literature and evidence from outbreaks making specific recommendations on several organisms.
c Acceptable to cohort asymptomatic cases and contacts at day-care.

Disease Trends in the U.S.:

From 1999-2002 there were 9572 cases reported; while from 2003-2005 there were 15685 cases reported in the U.S. The majorities of cases were associated with recreational water exposure and affected those ages one-nine and 30-39, which follows the trends in outbreak transmission from children to their caretakers (15, 16).

Food Associated Outbreaks:
Food associated cryptosporidiosis is rare and Quiroz et al. (2000) had only identified four such instances in the United States. In 1998 there was an outbreak “on a Washington, D.C. university campus and a case control study was undertaken that identified 88 cases and 67 controls. One ill food worker had handled raw produce and was identified as the likely source through epidemiological and molecular evidence (7).”

In 1997 there was an outbreak of gastrointestinal illness among those attending a banquet in Spokane, Washington with eight of ten fecal specimens submitted from those attending positive for Cryptosporidium. No single food item could be identified as associated with the outbreak; however green onions were implicated as being eaten in dishes by all 51 case patients. Two of fifteen food workers also tested positive. One had been symptomatic and the other asymptomatic while working at the banquet but both had also eaten food items containing the onions. There is no stated cause for the outbreak (6).

In 1995 there was an outbreak of gastrointestinal disease among 50 attendants of a social gathering in Minnesota. Fifteen of twenty-six people who attended the event and finished the interview had diarrhea start within 24 hours of the event. The case control study that was done as part of the investigation implicated the chicken salad that had been prepared by the hostess of the event. She also ran an out of home day-care and had changed diapers prior to making the salad, although she denied any diarrheal symptoms in herself or children attending her daycare. She refused to give a stool sample and no salad was available to test. This is therefore a potential outbreak from an asymptomatic carrier (14).

Outbreaks in Day Care Settings:
In 1998 there was a reported outbreak of cryptosporidiosis in a hospital day care center in Lisbon, Portugal. Twenty-eight attendees and one staff were infected. The index case was likely a 17-month old girl who had exhibited diarrheal illness for two days twelve days prior to when the outbreak was detected (18).

In 1984 an outbreak occurred in a hospital-associated day care with 27 children having cryptosporidium in their stool out of 54 infants and toddlers in the room of exposed individuals. The first case of cryptosporidiosis in the day care was discovered two weeks prior to the outbreak in a staff member who was a float staff in the center. It was not completely determined if she was the source of the outbreak or not. In total, three staff members were infected and secondary infections occurred in seven families with symptomatic children and two families with asymptomatic children associated with the outbreak (19).

Outbreaks in Hospital Setting:
In 1989 an outbreak of cryptosporidiosis occurred in a hospital in Denmark. There were a total of 20 secondary cases identified and the source of the outbreak was a symptomatic HIV patient who had been admitted to a closed psychiatric ward. Ice from the ice machine was identified as the most likely vehicle responsible for transmission, as it was the primary link of exposure between the index case and many of the secondary cases that had no direct contact with the patient. The index case had been seen picking ice out of the machine with his hands on several occasions and he was known to be “grossly negligent” about washing his hands (21).

In 1988 an HIV infected infant with Cryptosporidium diarrhea was identified as the common source of an outbreak in a pediatric hospital in Mexico. The likely vehicles of transmission for the outbreak were the hands of the staff (23).

In 1985 an HIV infected patient admitted to a hospital in the U.S. for a three-month history of diarrhea infected the intern taking care of him and eight other hospital personnel. The intern’s husband also became infected one week after the onset of his wife’s diarrhea (22).

Organism: Cryptosporidium parvum is a coccidian protozoa and an obligate intracellular parasite. It is associated with human and zoonotic infections. Molecular techniques revealed two genotypes of C. parvum: Type I only infects humans (anthroponotic genotype) and Type 2 (bovine or zoonotic genotype) infects cattle and other animals but also can infect humans. (1, 6, 7, 8, 10)

Reservoir of Infection: humans, cattle and other animals. (1, 6, 7, 8, 10, 11)

Modes of transmission: Fecal oral route resulting from ingestion of Cryptosporidium oocysts: human-to-human contact, human-to-animal contact, drinking contaminated water, eating contaminated food. Oocysts can produce an infection immediately after excretion (1, 6, 7, 8, 10, 11, 12, 15, 16).

Attack Rates: In day care environments can be 30-60% (11). Forty percent of household contacts of a symptomatic child may get infected, but fewer than 10% of those in contact with an asymptomatic carrier (12). When adults are infected the risk of secondary infection in family members is five percent (12).

Infectious Dose: Ten or fewer organisms however, even one organism can initiate an infection (12, 15, 16). Those infected can release up to 1000000000 organisms in a single stool (16).

Incubation Period: Seven days (3, 12, 13)

Infectious Period: The oocyst is present in the stool at symptom onset and excretion can last for several weeks after symptom resolution (1, 15, 16), with the longest cited period being 60 days (6). According to the CDC (2007), those who are at greatest risk for infection include persons who come into close contact with those infected (immediate family, those who share living quarters with them and those around them in child care settings) (16).

Carrier State: Asymptomatic infection and excretion after resolution of diarrhea (convalescent excretion) do occur (15, 17). Outbreak examination in day care centers revealed 3.7-22.9% of oocyst-positive children may be asymptomatic and prevalence investigations undertaken in non-outbreaks conditions reveal 55.6-75% of oocyst-positive children were asymptomatic (17). According to Chen et al (2002), “There are 4 common clinical disease presentations in HIV patients: 1. Asymptomatic infection where patient has less than 3 stools daily and no change in bowel habits (occurs in 4%). 2) Transient infection where diarrhea lasts 2 months and then stops and absence of cryptosporidium in stool specimen (29%). 3) Chronic diarrhea last longer than two months and cryptosporidium persist in stool (60%). 4) Fulminant infection infected individual passes 2 liters or more of watery stool each day (8%) (23).”
Diagnosis: Via identification of oocyst in fecal smear with acid-fast stain (auramine-rhodamine) (1, 10, 11, 14), also a more sensitive ELISA test is available (1, 10, 11, 14) and PCR can be used to identify exact species of parasite (7, 13).  According to the CDC (2007), “confirmed cryptosporidiosis is defined as the detection (in symptomatic or asymptomatic persons) of Cryptosporidium

• oocysts in stool or intestinal fluid by microscopic examination with or without staining (e.g., modified acid-fast) or by fluorescent antibody assays, either direct (DFA) or indirect (IFA); or
• oocyst or sporozoite antigens in stool or intestinal fluid by immunodiagnostic methods (e.g., enzyme immunoassay [EIA]); or
• Parasite DNA in stool, in intestinal or other bodily fluids (e.g., bile or sputum), or in tissue samples by polymerase chain reaction techniques when available; or life-cycle stages (e.g., trophozoites or merozoites) in tissue samples (16).”

Preventive Measures
Exclusions:

1. Exclude infected food handlers from work that places them in contact with food that will subsequently not be cooked (1 Guidelines and Consensus document). {Grade III-A}
2. Exclude all infected children who are symptomatic from day care setting until diarrhea resolves (1, 2, 3a, 4a, 5, 9, 17) Okay to cohort (keep convalescing children grouped together, and separated from others) asymptomatic cases and contacts at day-care (9, 17). Collection of guidelines and evidence based reviews. {Grade III-A}
3. Exclude all symptomatic individuals from direct patient care of hospitalized and institutionalized patients and return person to work when asymptomatic, but stress need for proper hand hygiene (1, 2, 3a, 4a, 5a, 6, 7, 8, 10) Collection of guidelines and evidence based reviews. {Grade III-A}
4. Given the fact that an adult asymptomatic carrier of this disease has only a 5% chance of spreading infection, the literature seems to favor them returning to work; however they must be unrelenting in their practice of proper hand hygiene (all sources in #3 above and 12, 17). Collection of guidelines and evidence based reviews. {Grade II-A}
5. According to Cordell RL & Addis (1994), “although the likelihood of transmission is probably greater if stools are watery and not contained by the diaper, at least two reports have suggested that children with asymptomatic Cryptosporidium infection are able to transmit infection to household contacts (17 Evidence Based Literature).” {Grade II-A}
6. According to Cordell RL & Addis (1994), if a cryptosporidiosis outbreak is suspected in day care contemplate screening those employees, children and home contacts of immunocompromised persons. Wider screening may be employed if infected and uninfected attendees are cohorted in the facility. It is permissible to cohort children with mild or controlled diarrhea in facility (17 Evidence Based Literature). {Grade II-A}
7. According to Cordell RL & Addis (1994), “the practice of excluding asymptomatically infected persons with Cryptosporidium or requiring those whose diarrhea has resolved to have a negative test for re-entry has not been evaluated as a control measure. As Cryptosporidium can be excreted for weeks, prolonged alternative childcare could result in spread to the broader community. In facilities where cohorting is not possible careful attention to hand-washing, diaper practices, use of diaper overclothes and periodic disinfection of the environment with hydrogen peroxide should be practiced (17 Evidence Based Literature).” {Grade II-A}
8. According to CDC (1998), “Food workers should not work when experiencing a gastrointestinal illness (6 Review of Outbreaks and Epidemiology)" {Grade II-A}
9. According to the CDC (2002) with respects to HIV infected persons “Cryptosporidium-infected patients should not work as food handlers, including if the food to be handled is intended to be eaten without cooking. Because the majority of foodborne outbreaks of cryptosporidiosis are believed to have been caused by infected food handlers… (20 Guidelines and Consensus document)” {Grade III-A}

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 2001:32:331-350. Evidence based reviews with guidelines formed out of reviewed literary sources
6. CDC. Foodborne Outbreak of Cryptosporidiosis—Spokane Washington, 1997. MMWR 1998; 42(27); 565-567. Review of Outbreaks and epidemiology.
7. Quiroz ES, Bern C, Mac Arthur JR, et al. An Outbreak of Cryptosporidiosis Linked to a Food Handler. The Journal of Infectious Disease 2000; 181:695-700. Review of Outbreaks and Epidemiology
8. Insulander M, Lebbad M, Stenstrom TA, et al. An outbreak of Cryptosporidiosis associated with exposure to swimming pool water. Scandinavian Journal of Infectious Disease 2005; 37:354-360. Review of Outbreaks and Epidemiology
9. 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. Guidelines and Consensus Document
10. CDC: Cryptosporidium and Water: A Public Health Handbook. Atlanta, Georgia: Working Group on Waterborne Cryptosporidiosis.1997. Pgs 68-71. Guidelines and Consensus Document
11. Dennehy PH, Acute Diarrheal Disease in Children: Epidemiology, Prevention, and Treatment. Infectious Disease Clinics of North America 2005 19: 585-602. Evidence Based Literature.
12. Musher, DM & Musher, BL. Contagious Acute Gastrointestinal Infections. NEJM 2004; 351; 23: 2417-27. Evidence Based Literature
13. Stroup SE, Roy S, Michele J, et al. Real Time PCR detection and Speciation of Cryptosporidium Infection using Scorpion Probes. Journal of Medical Microbiology 2006 55; 1217-12.Evidence Based Literature
14. CDC. Foodborne Outbreak of Diarrheal Illness Associated with Cryptosporidium Parvum—Minnesota 1995. MMWR 1996; 45(36): 783-784. Review of Outbreaks and Epidemiology
15. CDC. Cryptosporidiosis Surveillance - United States 1999-2002. MMWR 2005; 54(SS01); 1-8. Review of Outbreaks and Epidemiology
16. CDC. Cryptosporidiosis Surveillance - United States 2003-2005. MMWR 2007; 56(SS07); 1-10. Review of Outbreaks and Epidemiology
17. Cordell RL & Addis DG. Cryptosporidiosis in Child Care Settings: a Review of the literature and recommendations for Prevention and Control. Pediatric Infectious Disease Journal 1994; 13(4): 310-317. Evidence Based Literature.
18. Melo Cristino JA, Carvalho MI & Dalgado MJ. An outbreak of cryptosporidiosis in a hospital day-care. Epidemiology and Infection 1988; 101:355-359. Review of Outbreaks and Epidemiology.
19. Combee CL, Collinge ML & Britt EM. Cryptosporidiosis in a hospital associated day care center. Pediatric Infectious Disease Journal 1986; 5:528-532. Review of Outbreaks and Epidemiology
20. CDC. Guidelines for Preventing Opportunistic Infections among HIV-Infected Persons --- 2002
    Recommendations of the U.S. Public Health Service and the Infectious Diseases Society of America. MMWR 2002; 51(RR08): 1-46. Guidelines and Consensus Document
21. Ravn P, Lundgren JD, Kjaeldgaard P. et al. Nosocomial Outbreak of Cryptosporidiosis in AIDS Patients. British Medical Journal 1991; 302:277-280. Review of Outbreaks and Epidemiology
22. Koch KL, Phillips DJ, Aber RC et al. Cryptosporidiosis in Hospital Personnel Evidence for Person-to-Person Transmission. Annals of Internal Medicine 1985; 102:593-596. Review of Outbreak and Epidemiology
23. Chen XM, Keithly JS, Paya CV et al. Cryptosporidiosis. New England Journal of Medicine 2002; 346(22): 1723-1731. Evidence Based Literature

 

---