Infection Exposure Questions - Contagiousness
- This topic includes information about the transmission of common infections, including how long to stay out of school or child care.
- Incubation Period: Time interval between exposure to the infection and onset of symptoms.
- Contagious Period: Time interval during which a sick child's disease is contagious to others. With precautions, children sometimes can return to child care and school before this period is over.
- Infections that are not Contagious: Many common bacterial infections are not contagious (e.g., ear infections, sinus infections, bladder infections, kidney infections, and pneumonia). Sexually transmitted diseases are not contagious to children unless there is sexual contact or shared bathing.
Infection Exposure Table
|Chickenpox||10-21||2 days before rash until all sores have crusts (6 - 7days)|
|Fifth disease (Erythema infectiosum)||4-14||7 days before rash until rash begins|
|Hand, foot, and mouth disease||3-6||Onset of mouth ulcers until fever gone|
|Impetigo (strep or staph)||2-5||Onset of sores until 24 hours on antibiotic|
|Lice||7||Onset of itch until 1 treatment|
|Measles||8-12||4 days before rash until 4 days after rash appears|
|Roseola||9-10||Onset of fever until rash gone (2 days)|
|Rubella (German measles)||14-21||7 days before rash until 5 days after rash appears|
|Scabies||30-45||Onset of rash until 1 treatment|
|Scarlet fever||3-6||Onset of fever or rash until 24 hours on antibiotic|
|Shingles (contagious for chicken pox)||14-16||Onset of rash until all sores have crusts (7 days) (Note: No need to isolate if sores can be kept covered.)|
|Bronchiolitis||4-6||Onset of cough until 7 days|
|Colds||2-5||Onset of runny nose until fever gone|
|Cold sores (herpes)||2-12||Footnote 1|
|Coughs (viral) or croup (viral)||2-5||Onset of cough until fever gone|
|Diphtheria||2-5||Onset of sore throat until 4 days on antibiotic|
|Influenza||1-2||Onset of symptoms until fever gone over 24 hours|
|Sore throat, strep||2-5||Onset of sore throat until 24 hours on antibiotic|
|Sore throat, viral||2-5||Onset of sore throat until fever gone|
|Tuberculosis||6-24 months||Until 2 weeks on drugs (Note: Most childhood TB is not contagious.)|
|Whooping cough||7-10||Onset of runny nose until 5 days on antibiotic|
|Diarrhea, bacterial||1-5||Footnote 2 for Diarrhea Precautions|
|Diarrhea, giardia||7-28||Footnote 2 for Diarrhea Precautions|
|Diarrhea, traveler's||1-6||Footnote 2 for Diarrhea Precautions|
|Diarrhea, viral (Rotavirus)||1-3||Footnote 2 for Diarrhea Precautions|
|Hepatitis A||14-50||2 weeks before jaundice begins until jaundice resolved (7 days)|
|Pinworms||21-28||Minimally contagious, staying home is unnecessary|
|Vomiting, viral||2-5||Until vomiting stops|
|Infectious mononucleosis||30-50||Onset of fever until fever gone (7 days)|
|Meningitis, bacterial||2-10||7 days before symptoms until 24 hours on IV antibiotics in hospital|
|Meningitis, viral||3-6||Onset of symptoms and for 1-2 weeks|
|Mumps||12-25||5 days before swelling until swelling gone (7 days)|
|Pinkeye without pus (viral)||1-5||Mild infection, staying home is unnecessary|
|Pinkeye with pus (bacterial)||2-7||Onset of pus until 1 day on antibiotic eyedrops|
Cold sores: Less than 6 years old, contagious until cold sores are dry (4-5 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.
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.
Barton D. Schmitt, M.D.
Swedish Kids Symptom Checker is designed especially for these times. The interactive iPhone application can help you make appropriate decisions on what level of care, if any, is needed and how to provide symptom relief for minor illnesses and injuries you can manage on your own.