Who Should Stay Home From School and When? by Mark B. Levin, M.D. The Pediatric Group, P.A., Princeton

This is the twelveth article in a series written for Princeton Online. Click here for an archive of other articles.

We are often asked by parents and school personnel when a child may return to school after a contagious disease. The Academy of Pediatrics Committees on Infectious Diseases and School Health have compiled a list of the familiar diseases our children encounter. The compendium includes disease transmitted by the respiratory, gastrointeastinal and direct contact routes. The following is a modification of their work. We hope it will aid parents in deciding when to send their children back to school, preschool or day-care. Parents should contact their own child’s physician if they have specific questions regarding which illness a child has, whether their child fits the criteria for school exclusion and management of any underlying or comlicating situations.

Communicable diseases are easily transmitted in schools since children are brought together in groups of various sizes. This has long been a cause for concern for parents as well as for schoolteachers and administrative personnel. The control of these diseases in the school setting is multifaceted and requires the close collaboration of parents, school personnel, and health care professionals to institute a rational common-sense approach. In general terms, control may involve antimicrobial therapy or prophylaxis, exclusion, or cohorting. Closing of an educational facility for the purposes of communicable disease control is almost never required.

Mild illnesses are very common during the school years. However, there are very few illnesses that mandate exclusion from participation in school. Children with minor illnesses should not be excluded from school unless:

1. The illness prevents the child from participating in school activities.
2. The child requires more care than the school staff can provide.
3. Fever, lethargy, irritability, persistent crying, difficulty breathing, or other signs suggesting severe illness are present.
4. There are mouth sores associated with inability to control saliva, unless medical authority states that the child's condition is noninfectious.
5. There is rash with fever or behavior changes (until illness is determined by a physician not to be communicable).
6. As indicated in the discussion of specific diseases in the following section. There is no evidence that the incidence of acute common respiratory diseases such as the common cold, croup, bronchitis, or pneumonia can be reduced by exclusion; thus, exclusion is not recommended for these diseases. Our general recommendation is for children to remain out of school until they are fever-free for 24 hours (temperature under 100 oF) and feeling well. Specifics for certain diseases are listed below.

The following diseases are spread primarily by the respiratory route.

1. Erythema infectiosum (Fifth Disease)

a. Description of clinical disease: Erythema infectiosum (fifth disease) is a mild infectious disease with fever in only 15% to 30% of cases. It is characterized by a distinc- tive rash that begins with red cheeks and progresses in 1 to 4 days to a lacy flat or slightly raised rash on the arms that spreads centrally to involve the trunk. The rash recurs and fluctuates in intensity over a 1- to 3-week period.
b. Age group most commonly affected: School-age children.
c. Seasonal incidence: Highest incidence is in the winter and spring.
d. Incubation period: Most commonly 4 to 14 days to development of rash, but can be as long as 20 days.
e. Period of communicability: Not well delineated, but greatest just before onset of rash and probably not thereafter.
f. Exclusion: Children are most infectious before the onset of illness and unlikely to be infectious after the onset of rash and other associated symptoms. So, exclusion is not indicated.

2. Measles (Most U.S. children have been immunized for this disease.)

a. Description of clinical disease: Measles is a very contagious disease, with a 1 to 2 day prodrome of malaise and fever followed by the onset of runny nose, conjunctivitis, a dry cough, and the appearance of a flat to slightly raised rash. Characteristically, the rash starts on the head and neck, spreads over the rest of the body, and disappears 5 to 7 days after onset.
b. Age group most commonly affected: Most cases occur in preschool children. However, currently more than 40% of cases occur in those older than 10 years.
c. Seasonal incidence : The peak incidence of infection is during the winter and spring.
d. Incubation period: 8 to 12 days from exposure to onset of symptoms with an average interval of 14 days to appearance of rash.
e. Period of communicability: 1 to 2 days before the onset of symptoms, or 3 to 5 days before the appearance of rash until 4 days after rash appearance.
f. Exclusion: Children should be excluded from school at least 4 days after the onset of rash.

3. Mumps (Most U.S. children have been immunized for this disease.)

a. Description of clinical disease: Mumps is an acute contagious disease, with onset of low-grade fever, headache, loss of appetite, and malaise followed in 24 to 48 hours by swollen, painful, tender salivary glands, primarily the parotid (behind the jaw and under the ear). In about 25% of cases the swelling is unilateral. The salivary gland involvement lasts 7 to 10 days and the lack of a prodrome is not unusual. Approximately one third of cases of mumps infection are not characterized by glandular swelling.
b. Age group most commonly affected: Infection occurs throughout childhood with infection in the older patient being more likely to result in severe disease.
c. Seasonal incidence: Mumps is more common during late winter and spring.
d. Incubation period: 16 to 18 days, but cases may occur as early as 12 or as late as 25 days after exposure.
e. Period of communicability: Usually 1 to 2 days. However, the period may be as long as 7 days before onset of parotid swelling and occasionally as long as 9 days after onset.
f. Exclusion: Children should be excluded from school until 9 days after the onset of parotitis (inflammation of the parotid glands).

4. Pertussis (Whooping Cough) (Most U.S. children have been immunized for this disease.)

a. Description of clinical disease: Pertussis (whooping cough) is a contagious disease that begins with mild upper respiratory tract symptoms and proceeds to severe cough paroxysms with the characteristic inspiratory "whoop," often followed by vomiting. Fever is not a prominent feature, and the total course of the disease is usually 6 to 10 weeks.
b. Age group most commonly affected: Approximately 30% of cases occur in infants younger than 6 months, and 75% of cases occur in children younger than 5 years. Recently, pertussis in adolescence, ranging from a mild illness to the full-blown syndrome has been increasingly frequent.
c. Seasonal incidence: There is little seasonal variation in the occurrence of pertussis.
d. Incubation period: 6 to 20 days, but usually 7 to 10 days and rarely longer than 2 weeks.
e. Period of communicability: Most common during the early runny nose stage before paroxysms, and extending until 3 weeks after this onset of paroxysms of coughing. When treated with erythromycin, the period of infectiousness is usually limited to the 5 days after onset of therapy.
f. Exclusion: Cases should be excluded from school until 3 weeks after onset of the paroxysmal stage or until on erythromycin therapy for 5 days.

5. Rubella (Most U.S. children have been immunized for this disease.)

a. Description of clinical disease: Rubella is usually a mild illness with a minimal fever and a flat or slightly raised rash that usually starts on the face or upper trunk and extends over the rest of the body The rash usually lasts about 3 days and is often accompanied by swollen glands behind the ears and at the rear of the skull. As many as half of rubella infections do not manifest a rash.
b. Age group most commonly affected: In the pre-vaccine era, rubella was primarily a disease of childhood: Today, infections in adolescents have become important.
c. Seasonal incidence: Rubella is more common during late winter and early spring.
d. Incubation period: 16 to 18 days, with outside limits of 14 to 21 days.
e. Period of communicability: One week before until 5 to 7 days after onset of rash
f. Exclusion: Children should be excluded from school for 7 days after onset of rash

6. Streptococcal pharyngitis

a. Description of clinical disease: Streptococcal pharyngitis is a contagious disease usually characterized by fever, sore throat, tonsillitis with pus, and tender lymph nodes in the front of the neck. However, symptoms may be minimal.
b. Age group most commonly affected: The 3- to 15-year age group is most commonly affected.
c. Seasonal incidence: The highest incidence is during late fall, winter, and spring.
d. Incubation period: The incubation period is short, usually 2 to 5 days, occasionally longer.
e. Period of communicability: The period of communicability is 10 to 21 days in untreated cases. Transmissibility usually ceases 24 to 28 hours after institution of adequate therapy. Untreated persons may carry the organisms in their throats for weeks to months, most commonly in decreasing numbers. The contagiousness of these carriers is markedly reduced after 2 to 3 weeks.
f. Exclusion: Children should be excluded from school until they are afebrile and at least until 24 hours after the institution of appropriate antimicrobial therapy.

7. Tuberculosis

a. Description of clinical disease: Primary tuberculosis is almost always a disease of the lungs. Most children are asymptomatic when first infected and early clinical manifestations, which may include swollen lymph glands in the chest, involvement of a lung segment, partial lung collapse, or fluid around the lung, may not be apparent for 1 to 6 months. Fatigue, fever, and weight loss may occur early while cough, chest pain, coughing up blood and hoarseness may follow.
b. Age group most commonly affected: All ages are susceptible, but infants and pubertal children are at higher risk
c. Seasonal incidence: No increased seasonal incidence has been identified.
d. Incubation period: The incubation period from infection to development of a positive skin test is 2 to 10 weeks. After infection, the maximum risk of disease is during the first year. Months to years may elapse between infection and development of disease. Usually infection does not progress to clinical disease.
e. Period of communicability: In adults on therapy, the period of infectivity is a few days to a few weeks. In contrast, if lung cavity formation is not present, children are generally not infectious.
f. Exclusion: Until the child's physician or local health department authority states that the child is noninfectious. Children with primary tuberculosis may attend school if they are on antibiotic therapy.

8. Varicella-zoster (chickenpox) (Many, but not all, U.S. children have been immunized for this disease.)

a. Description of clinical disease: Primary varicella (chickenpox) is an acute, very contagious disease having an onset with low-grade fever and malaise and accompanied by a generalized blister rash, which usually starts on the scalp or upper trunk. Characteristically, the lesions are in different stages of evolution and there is very little subclinical disease. Following primary infection, the virus may remain latent in the cells along the spine. Reactivation of the latter results in herpes zoster (shingles) with its characteristic distribution along the path of the infected nerve.
b. Age groups most commonly affected: Prior to the advent of varicella vaccine, most cases of chickenpox occurred in children between 5 and 10 years of age. Disease in the older patient tends to be more severe.
c. Seasonal incidence: Chickenpox is more common during late winter and early spring.
d. Incubation period: 11 to 20 days.
e. Period of communicability: 1 to 2 days before and shortly after onset of rash, but contagiousness may persist as long as 5 days after the appearance of lesions.
f. Exclusion: Children should be excluded from school until the 6th day after onset of rash, but may return sooner if lesions are dry or crusted. Children with zoster may return to school when the lesions have crusted.

The following diseases are spread primarily by the fecal-oral route.

1. Acute gastroenteritis (vomiting/diarrheal disease; coxsackie infections = hand-foot- mouth):

a. Description of clinical disease: Gastroenteritis is primarily a disease of infants and young children characterized by fever and vomiting, followed by watery diarrhea that occasionally may be severe. Symptoms last 2 to 5 days.
b. Age group most commonly affected: Disease most commonly occurs in infants and young children.
c. Seasonal incidence: Cases occur at all times of the year, but rotavirus infections, the most common cause of diarrhea in children, occur more commonly in the colder months. Coxsackie infections occur mostly in the warm weather months. d. Incubation period: 24 to 72 hours.
e. Period of communicability: During the acute stage of the illness and for a short time thereafter while the infectious agent is still being excreted.
f. Exclusion: Vomiting two or more times in the previous 24 hours should result in exclusion from school unless disease is determined to be noncommunicable and the child is not in danger of dehydration. Children in whom stool cannot be contained by toilet use also should be excluded until the diarrhea is resolved (that, is a return to the normal stooling pattern for the child). Children with active oral lesions should be excluded. Handwashing after toileting, after diaper changes and before eating is essential.

2. Hepatitis A

a. Description of clinical disease: Hepatitis A usually has an abrupt onset with malaise, fever, appetite loss and nausea, followed by the onset of jaundice in a few days. The illness ranges from very mild to very severe and disabling. Many infections in children are asymptomatic or mild.
b. Age group most commonly affected: The disease is most common among older schoolchildren and young adults.
c. Seasonal incidence: There is no appreciable seasonal variation in the incidence of disease.
d. Incubation period: 15 to 50 days, with an average of 25 to 30 days.
e. Period of communicability: Period of contagiousness is about 1 to 3 weeks, with the highest amount of virus being present in stools 2 weeks before the onset of illness. The infectivity risk then diminishes and is minimal 1 week after the onset of jaundice.
f. Exclusion: Children should be excluded from school for 1 week after the onset of the illness and until jaundice, if present, has disappeared or until gamma globulin has been administered to appropriate children and staff as directed by the health officials.

The following diseases are spread primarily by direct contact.

1. Conjunctivitis

a. Description of clinical disease: Infection begins with bloodshot eyes and increased tears, followed by swollen eyelids and discharge of pus. The infection may last from 2 days to 2 to 3 weeks.
b. Age group most commonly affected: All ages can be infected, but incidence decreases as children grow older.
c. Seasonal incidence: There may be some seasonal predilection depending upon the organism, but, in general, occurrence is year-round.
d. Incubation period: Approximately 24 to 72 hours to 14 days , depending on the organism.
e. Period of communicability: Children are infectious during the course of active infection.
f. Exclusion: Children should be excluded from school while there is a discharge of pus and until they have been treated with antibiotic eye drops for at least 24 hours.

2. Impetigo

a. Description of clinical disease: A superficial skin infection that commonly proceeds through blister, pus-head, and scab stages.
b. Age group most commonly affected: Incidence of impetigo is highest in young children.
c. Seasonal incidence: Disease is most common in late summer and fall.
d. Incubation period: Usually 7 to 10 days.
e. Period of communicability: Disease is transmissible when lesions are active by draining or until 24 hours after institution of therapy
f. Exclusion: Children should not attend school until at least 24 hours after institution of therapy, and they are without fever.

3. Pediculosis capitis (head lice)

a. Description of clinical disease: Pediculosis is an infestation of the head with lice, and nits, resulting in severe itching and excoriation
b. Age group most commonly affected: Infestations are most common in child care and school-age children.
c. Seasonal incidence: There is no appreciable seasonal variation.
d. Incubation period: 7 to 14 days.
e. Period of communicability: Disease transmission may occur as long as lice or eggs are viable on the infested person or clothing.
f. Exclusion: Children should be excluded from school until the morning after the first treatment.

4. Scabies

a. Description of clinical disease: Scabies is caused by mites whose skin penetration is characterized by red bumps, small blisters, or red lines, commonly contain- ing the mites and their eggs. Frequently involved areas include finger webs, wrists, elbows, front of the armpits, beltline, thighs, and buttocks. Itching is prominent, particularly at night. Lesions may become infected secondary to scratching.
b. Age group most commonly affected: All age groups are affected.
c. Seasonal incidence: There is no significant seasonal variation in disease.
d. Incubation period: In persons without previous exposure, 4 to 6 weeks before onset of itching; in re-exposure, 1 to 4 days.
e. Period of communicability: Communicable until eggs and mites are destroyed by therapy.
f. Exclusion: Infected individuals should be excluded from school until the day after therapy is completed. Many schools have a “no-nit policy”.

5. Tinea (ringworm)

a. Description of clinical disease: Ringworm begins as a small papule and spreads outward resulting in scaly patches that are pink or red at the edge and normal skin color centrally. On the scalp, infected hairs become very brittle and have a tendency to break off causing an area of baldness. Boggy lesions with pus under the scalp known as kerions may develop.
b. Age group most commonly affected: All ages are susceptible, but particularly children between the ages of 2 and 10 years.
c. Seasonal incidence: No particular seasonal predilection has been noted. d. Incubation period: 10 to 14 days.
e. Period of communicability: Communicable as long as fungi can be cultured from the infected area or demonstrated by fluorescence (glowing greenish under a purple light, or until treated for at least 24 hours.
f. Exclusion: Children should be excluded from school until 24 hours after initial treatment.

The following diseases are spread primarily by body fluids such as saliva, urine, blood, and semen

1. Acquired immunodeficiency syndrome (AIDS)

a. Description of clinical disease: AIDS is a severe, life threatening disease that progressively damages the immune system. The onset of clinical illness is usually insidious and characterized by nonspecific symptoms such as malaise, appetite loss, fatigue, diarrhea, weight loss, swollen glands, and fever. Eventually the patient is afflicted with serious infections, frequently with germs that are normally harmless.
b. Age group most commonly affected: Young adults.
c. Seasonal incidence: There is no evidence of seasonal predilection.
d. Incubation period: Variable. Antibodies are usually detectable 1 to 3 months after infection. Period from infection to detection of disease ranges from 2 months to 10 years or longer.
e. Period of communicability: Unknown, but presumed to extend from shortly after infection through life.
f. Exclusion: Since human immunodeficiency virus (HIV) infection or AIDS is not acquired by casual contact, children and adolescents infected with HIV should be allowed to attend school without restriction unless they manifest severe aggressive behavior; such as biting, or have weeping skin sores that cannot be covered.

2. Cytomegalovirus

a. Description of clinical disease: Congenital infection is usually asymptomatic, but unusually can result in mild or severe mental retardation or even death. Acquired infection is usually asymptomatic but may unusually cause a disease similar to Epstein-Barr virus- induced mononucleosis (infectious mono) in young adults. Immunodeficient or immunosuppressed patients may develop severe disseminated infection.
b. Age group most commonly affected: In highly developed countries, serum antibody prevalence in young adults approximates 40%, while in developing countries it is almost 100%. Acquisition of antibody is inversely related to socioeconomic group.
c. Seasonal incidence: There is no seasonal predilection.
d. Incubation period: Incubation period for acquired disease varies from 3 to 12 weeks.
e. Period of communicability: Months to years as virus is excreted in urine and saliva for prolonged periods.
f. Exclusion: Exclusion from school is not indicated.

3. Hepatitis B

a. Description of clinical disease: Hepatitis B usually has an insidious onset with appetite loss, vague abdominal pain, nausea and vomiting, and, occasionally, joint pain and rash. Jaundice is often present, but fever may be absent or mild. Clinical presentation ranges from inapparent to fulminant. The disease is milder in children than in adults and often lacks jaundice .
b. Age group most commonly affected: In North America, infection is most common m young adults.
c. Seasonal incidence: Very little seasonal variation.
d. Incubation period: Incubation period is 45 to 160 days, with an average of 120 days.
e. Period of communicability: Blood from infected persons is infectious many weeks before onset of symptoms through the clinical course of the acute disease and during the chronic carrier state, if such ensues.
f. Exclusion: There is no reason to exclude from school unless there is unusually aggressive behavior, such as biting.

4. Hepatitis C

a. Description of clinical disease: Hepatitis C, like hepatitis B, is characterized by an insidious onset of malaise, appetite loss, nausea, vomiting, and abdominal pain. Jaundice is less likely than with hepatitis B, and severity ranges from inapparent infection to fulminant disease.
b. Age group most commonly affected: Disease is most frequently recognized in adults, and reported cases in children younger than 15 years are uncommon.
c. Seasonal incidence: There is no seasonal predilection.
d. Incubation period: 7 to 9 weeks, with a range of 2 to 12 weeks.
e. Period of communicability: From 1 or more weeks before onset of symptoms through the acute disease and into the carrier state, if such ensues.
f. Exclusion: There is no reason to exclude from school unless very aggressive behavior, such as biting, is present.

5. Herpes simplex, oral (cold sores)

a. Description of clinical disease: Herpes simplex is a viral infection characterized by localized blistered lesions with a tendency to latency and recurrence (fever blisters or cold sores). The primary illness may be mild or inapparent, or may manifest with extensive lesions accompanied by fever and malaise lasting a week or more.
b. Age group most commonly affected: Initial infection usually occurs before age 5 years, with recurrent disease covering many subsequent years.
c. Seasonal incidence: No seasonal variation has been noted.
d. Incubation period: 2 to 14 days.
e. Period of communicability: As long as 7 weeks after recovery from disease.
f. Exclusion: Exclusion of children from school is not indicated, unless control of saliva is not possible (preschoolers). Once lesions are scabbed, a child should no longer be excluded.

10/98: Modified and adapted from School Health: Policy and Practice, 5th Edition, Committee on School Health, American Academy of Pediatrics, 1993 and Red Book, Report of the Committee on Infectious Diseases, 24th Edition, American Academy of Pediatrics, 1997.

All Rights Reserved 11/98 The Pediatric Group, P.A.

Dr. Levin has been a member of the staff at The Pediatric Group since 1977. Currently an attending Pediatrician at the Medical Center at Princeton, he has been Chairman, Department of Pediatrics, Medical Center at Princeton, 1984 to 1986, 1989 to 1992, and past President, Medical and Dental Staff, Medical Center at Princeton, 1987 to 1988. Dr. Levin has served on numerous Departmental and hospital committees. He has published original articles both while at Upstate Medical Center in Syracuse and at The Pediatric Group. He has a wife and three children. Dr. Levin enjoys alpine skiing, jogging, hiking and camping, travel, computers and racquetball.