Infection Exposure Questions
Definition:
- This guideline includes information about the transmission of common infections
- 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 day care and school before this period is over
- Infections that are not Contagious: Many common bacterial infections are not contagious (eg otitis media, sinusitis, urinary tract infection, pneumonia, and bacteremia). Sexually-transmitted diseases are not contagious to children unless there is sexual contact or shared bathing
Skin Infections/Rashes:
| DISEASE | INCUBATION PERIOD (DAYS) | CONTAGIOUS PERIOD (DAYS) |
|---|---|---|
| Chickenpox | 10-21 | 2 days before rash until all sores have crusts – (6-7 days) |
| 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 rash gone (7 days) |
| Roseola | 9-10 | Onset of fever until rash gone (2 days |
| Rubella (German measles) | 14-21 | 7 days before rash until rash gone (4 days) |
| 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.) |
| Warts | 30-180 | Minimally contagious |
Respiratory Infections:
| DISEASE | INCUBATION PERIOD (DAYS) | CONTAGIOUS PERIOD (DAYS) |
|---|---|---|
| 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 cough until fever gone |
| 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 |
| *see footnote 1 at bottom of the page |
Intestinal Infections:
| DISEASE | INCUBATION PERIOD (DAYS) | CONTAGIOUS PERIOD (DAYS) |
| 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) |
| Hepatitis B | 50-180 | 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 |
Other Infections:
| DISEASE | INCUBATION PERIOD (DAYS) | CONTAGIOUS PERIOD (DAYS) |
|---|---|---|
| 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 |
| 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 |
*Footnotes:
- Cold sores: younger than 6 years, 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 BMs. Shigella and E-coli 0157 require extra precautions.