When to keep your sick child home from school

April 4, 2017

Swedish Blogger

If you’re a parent, it’s probably safe to assume that you have at one time or another received the dreaded call. You know the call. You get it while you’re in a meeting or getting coffee. You look down at the caller ID. “Kid’s school.” You let it go to voicemail so you have time to mentally prepare yourself for explaining why your child thought giving the class hamster a mohawk was a good idea. You press “play” on the voicemail and you hear, “Good afternoon. Please come pick up your child. She came to the nurse’s office, and she has a fever.” First, you sigh with relief that the hamster still has its luscious locks. Second, and more importantly, you ask yourself: When can my kiddo go back to school?

Incubation and contagious periods

The answer depends on what’s causing your child to feel sick. Every cough, cold, rash and upset stomach has unique characteristics for diagnosis and treatment. And when you ask your child’s doctor when your little one can return to a play group or school, your doctor is thinking about two specific characteristics of the pathogens that make kids sick:

Incubation period: The time between exposure to an illness or infection and the start of symptoms. Each cold or rash has a different incubation period.
Contagious period: The interval during which a child’s illness is contagious to others.

No one size fits all

Sometimes incubation and contagious periods overlap, and sometimes they don’t. For instance, erythema infectiosum, known as fifth disease or “slapped cheek” rash, is contagious from about halfway through its incubation period until you see the characteristic cheek rash on your child.

In comparison, hand, foot and mouth disease has an incubation period of up to one week, but it isn’t contagious until its symptoms -- mouth sores and a rash on the hands and feet -- are noticeable.

The list below gives the incubation and contagious periods for many common childhood illnesses.

Disease, Incubation period, and Contagious period

Skin infections/rashes

Chickenpox 10-21 days; Two days before rash until all sores have crusts (Six to seven days)
Fifth disease (erythema infectiosum) 4-14 days; Seven days before rash until rash begins
Hand, foot and mouth disease 3-6 days; Onset of mouth ulcers until fever gone
Impetigo (strep or staph) 2-5 days; Onset of sores until 24 hours on antibiotic
Lice 7 days; Onset of itch until one treatment
Measles 8-12 days; Four days before rash until four days after rash appears
Roseola 9-10 days; Onset of fever until rash is gone (two days)
Rubella (German measles) 14-21 days; Seven days before rash until five days after rash appears
Scabies 30-45 days; Onset of rash until one treatment
Scarlet fever 3-6 days; Onset of fever or rash until 24 hours on antibiotic
Shingles (contagious for chicken pox) 14-16 days; Onset of rash until all sores have crusts (seven days) (Note: No need to isolate if sores can be kept covered.)
Warts 30-180 days; Minimally contagious

Respiratory infections

Bronchiolitis 4-6 days; Onset of cough until seven days
Colds 2-5 days; Onset of runny nose until fever gone
Cold sores (herpes) 2-12 days; Footnote 1
Coughs (viral) or croup (viral) 2-5 days; Onset of cough until fever gone
Diphtheria 2-5 days; Onset of sore throat until four days on antibiotic
Influenza 1-2 days; Onset of symptoms until fever gone
Sore throat, strep 2-5 days; Onset of sore throat until 24 hours on antibiotic
Sore throat, viral 2-5 days; Onset of sore throat until fever gone
Tuberculosis 6-24 months; Until two weeks on drugs (Note: Most childhood TB is not contagious.)
Whooping cough 7-10 days; Onset of runny nose until five days on antibiotic

Intestinal infections

Diarrhea, bacterial 1-5 days; Footnote 2 for diarrhea precautions
Diarrhea, giardia 7-28 days; Footnote 2 for diarrhea precautions
Diarrhea, traveler's 1-6 days; Footnote 2 for diarrhea precautions
Diarrhea, viral (Rotavirus) 1-3 days; Footnote 2 for diarrhea precautions
Hepatitis A 14-50 days; Two weeks before jaundice begins until jaundice resolved (seven days)
Pinworms 21-28 days; Minimally contagious, staying home is unnecessary
Vomiting, viral 2-5 days; Until vomiting stops

Other infections

Infectious mononucleosis 30-50 days; Onset of fever until fever is gone (seven days)
Meningitis, bacterial 2-10 days; Seven days before symptoms until 24 hours on IV antibiotics in hospital
Meningitis, viral 3-6 days; Onset of symptoms and for one to two weeks
Mumps 12-25 days; Five days before swelling until swelling is gone (seven days)
Pinkeye without pus, viral 1-5 days; Mild infection, staying home is unnecessary
Pinkeye with pus, bacterial 2-7 days; Onset of pus until one day on antibiotic eye drops

Notes

1. Cold sores: Less than 6 years old, contagious until cold sores are dry (four to five days). No isolation if sores are on part of body that can be covered. More than 6 years old, no isolation necessary if beyond touching, picking stage.

2. Diarrhea Precautions: Contagious until stools are formed. Stay home until fever is gone, diarrhea is mild, blood and mucus are gone, and toilet-trained child has control over loose stools. Shigella and E. coli 0157 require extra precautions. Consult your child care provider regarding attendance restrictions.

Mystery illness?

A lot of childhood fevers aren’t easily categorized, or children may have vague symptoms and “just don’t feel good.” What we like to tell parents is that their child is most likely not contagious and is safe to return to school -- hamster haircuts and all -- if the child:

Is fever-free for 24 hours
Has enough energy and willingness to go to school
Can stay well hydrated
Is able to tell a teacher or the school nurse if they aren’t feeling well

Save the information provided here for future reference. It’s bound to come in handy.

If your child is sick and you aren’t sure of a diagnosis, call Swedish Pediatrics at 800-793-3474 to schedule an appointment. You can find a primary care clinic here.