Shigellosis (child care and schools)

What is shigellosis? 

Shigellosis is an intestinal illness caused by any bacteria in the Shigella family. While less common than many of the other enteric pathogens, the number of shigellosis cases has been increasing in recent years. A very small dose of Shigella bacteria can cause illness and recreational bodies of water such as lakes and ponds can be a source of infection when contaminated. Humans are the primary reservoir for Shigella; it is uncommon for animals to carry or spread this type of bacteria. The illness is usually self-limiting, lasting four to seven days. 

Signs and symptoms

• Diarrhea (sometimes with blood or mucus)
• Abdominal cramps
• Nausea
• Fever
• Vomiting
• Dehydration, which may be severe especially among infants 

Incubation period

One to seven days (usually one to three days)

Contagious period and spread

• Shigella is spread by the fecal→oral route. People can become ill with Shigella from person-to-person contact, by eating food contaminated by people with infection (in particular foods eaten raw), drinking or swimming in contaminated water, or by coming into contact with contaminated surfaces. Shigellosis is highly contagious and spreads easily from person-to-person, especially in child care facilities. 
• People are contagious as long as the organism is present in the stool, which can be several weeks. People with diarrhea are more likely to spread it than those who are infected but do not have symptoms. 

Public health reporting requirements

• Staff who become aware of illness should report the infection to the facility director or school nurse. 
• The facility should report any confirmed or suspected cases to the local or state health department within four days being notified of the diagnosis.
• If other children or staff are ill with diarrhea, refer them to their health care providers, and contact public health as soon as possible as this could be an outbreak. Generally speaking, it is considered an outbreak if there is an increase from baseline in the number of ill children and/or staff members at the school or child care center.

Control of spread

• When a case of shigellosis occurs in a child care center attendee or worker, immediate involvement of public health authorities is critical. Shigella spreads very quickly through child care centers, but can be controlled if appropriate action is taken.
• Consult with local or state public health with implementation of control measures.
• Encourage and teach the importance of frequent handwashing, especially after using the toilet, changing diapers, and before eating. Directly supervise handwashing of children aged 5 years or younger. Reinforce and teach the importance of meticulous handwashing in school and child care facilities, especially after diapering, using the restroom, or assisting with children with toileting. This should be verified and emphasized by environmental health during inspections. Sample signs showing when and how to wash hands are included on the department’s child care health regulations webpage under “Preventing illness” and in the hand hygiene section of this website section. Post these or similar signs throughout the child care center or school to remind staff and children to wash their hands. 
• Perform more frequent cleaning and disinfection of toys, bathrooms, diapering areas, and food preparation areas during this time. Suspend the use of “play” dough and water tables.
• Promptly sanitize/disinfect contaminated surfaces (like diaper-changing areas) and other commonly touched surfaces (like toys), and discard food or water if it is thought to be contaminated. See Disease Prevention: The Facility Environment.
• Refer to Disease Prevention: Food Safety for information on food safety.
• Alert possibly exposed family and staff members to watch for symptoms and provide them with prevention tips. See recommendations for caregivers and the family section below.
• Refer to Shigellosis Outbreak Investigation & Control In Child Care Centers / Preschools

Treatment

Most shigellosis infections are self-limited, resolve in four to seven days, and do not require antibiotics, but some people can experience symptoms for four or more weeks. Some people can be infected and not show any symptoms. Antibiotics may be effective in slightly shortening the duration of diarrhea and eradicating organisms from feces, although some antibiotics will not eliminate these bacteria. Antibiotic treatment is recommended for cases with severe disease, dysentery, or underlying immunosuppressive conditions. Some Shigella bacteria have become resistant to certain antibiotics. Laboratory tests can determine which antibiotics are effective for a specific Shigella case. 

Exclusion

EXCLUDE all infected children and/or staff until at least 24 hours after diarrhea has resolved, without the use of anti-diarrheal medications, AND 

• Child care and preschool
  • EXCLUDE all children, staff, and caregivers infected with shigellosis until cleared by public health. Clearance by public health may require two consecutive negative stools collected 24 hours apart, 48 hours after completion of antibiotics.
    Ill children should not go to another facility during the period of exclusion.
  • When a case of Shigella is identified in a child attending child care, determine whether additional children have or have recently had diarrhea. Other children with diarrhea should be excluded, seen by their physician, and submit stool for Shigella testing. If other cases in the center are identified, work with public health and consider sending a letter home to parents/guardians/caregivers. 
  • If the case is the only child in the classroom or center who has been ill, no further action is indicated for other children in that classroom or center.
  • Staff with no role in food preparation or feeding (e.g. office staff) may return to work after diarrhea has been resolved for at least 24 hours without follow-up stool testing.
• Primary and secondary school
  • Students or staff with Shigella infection should be excluded until at least 24 hours after their diarrhea has resolved.
  • Children who wear diapers or have developmental delays resulting in fecal incontinence or hygiene concerns should be excluded until cleared by public health, which may require negative testing.
  • Students or staff who handle food and have a Shigella infection must not prepare food until at least 24 hours after their diarrhea has resolved and have two consecutive negative stool tests taken at least 24 hours apart (collected at least 48 hours after completion of antibiotic therapy, if antibiotics are given).

Role of teachers, caregivers, and family

• If your child or a child you care for is infected with Shigella, follow the advice of the child’s health care provider. 
• Practice good handwashing, especially after changing diapers, going to the bathroom or helping a child go to the bathroom, or handling food. Diapering, bathroom, and food preparation areas should be cleaned and disinfected frequently. 
• Ill individuals should not prepare food for other individuals until symptoms resolve. 
• Infected individuals should not swim or wade in pools or other recreational water while experiencing diarrhea.

Resources

Shigella (CDC)