Chickenpox (Varicella) and Shingles (Herpes Zoster)
What is Chickenpox?
Chickenpox (varicella) is a highly contagious illness caused by the varicella-zoster virus (VZV). The virus remains inactive in the person’s nerve cells after chickenpox resolves, and reactivation can occur later in life resulting in shingles. A vaccinated person may get chickenpox as a mild illness with fewer lesions that might not be blister-like.
Chickenpox: Signs and symptoms
- Rash (small red spots/bumps developing into small fluid-filled sacs over three to four days then forming scabs or “crusts” over four to seven days)
- Crops of lesions appear over several days resulting in rash in various stages
- Rash may appear inside mouth, ears, genital areas, and scalp
- Fever, runny nose, cough
- Loss of appetite
- Headache
- Fatigue
Shingles: Signs and symptoms
Itchy or painful rash of red bumps or blisters, usually in a narrow area on one side of the body.
Incubation period
Ranges from 10-21 days (usually 14-16 days).
Contagious period and spread
- A person is contagious with chickenpox one to two days before the rash appears and until all the blisters have crusted over (usually five days after rash onset). A person
with shingles is contagious until all blisters have scabbed or crusted over. - Chickenpox is spread through the air when a person with infection coughs and/or sneezes, or by direct contact with the rash of a person with infection.
- Direct contact with a shingles rash (prior to crusting) can cause chickenpox in people not immune to chickenpox.
Public health reporting requirements
- Report cases of chickenpox to the state or local public health agency within four days of a suspected or confirmed diagnosis. Shingles does not need to be reported.
- Report outbreaks of chickenpox with three or more cases within 21 days.
- A notification letter can be used to notify parents/guardians of exposed children. Unvaccinated children who receive a dose of the vaccine within 3 to 5 days are less likely to become seriously ill. A sample letter to notify parents and additional resources are available on the CDPHE varicella website.
- Notify those who might be pregnant or have a problem with their immune system to check with their health care providers.
Control of spread
- Varicella vaccine administered to people without evidence of varicella immunity within three to five days of exposure may prevent the disease.
- Properly dispose of articles soiled with nose/throat discharges.
- Use good surface-sanitation technique and good hand-hygiene technique at all times.
- Exclusion of individuals with contagious chickenpox infection.
- Varicella Zoster Immune Globulin (VariZIG) is recommended for contacts whom the vaccine is contraindicated and has a high risk for complications. VariZIG can be given up to 10 days after exposure.
Vaccination
Routine child/adolescent recommendations:
- Chickenpox (varicella) vaccines are routinely given to children at 12-15 months of age with a second dose at 4-6 years of age. Children may develop a rash after varicella vaccination. This rash usually occurs withing 5-26 days after vaccination and occurs around the injection site.
Colorado school-required vaccines:
- Child care/preschool: One dose of varicella for children who are 16 months of age and older and two doses of varicella prior to kindergarten entry.
- School (K-12): Two doses of varicella is required.
- A provider’s diagnosis of varicella, a lab-confirmed history of varicella, or a complete school-required vaccine exemption provided to the child/adolescent’s school may be accepted in place of documentation of an age-appropriate varicella vaccination series.
Routine adult/other recommendations:
- Varicella vaccine is recommended for some adults in special situations.
- A vaccine for the prevention of shingles is routinely recommended at 50 years of age or between 19-49 years of age with risk.
Treatment
- Antiviral medication may be used for people at increased risk of severe disease. Consult with a doctor for treatment options.
- Acetaminophen (Tylenol®) may be used to lower fever and reduce discomfort. Aspirin should be avoided because it increases the risk of Reye's Syndrome, a serious disorder that can lead to coma and death.
Exclusion
- Exclude all children, students, and/or staff with chickenpox until all vesicles have scabbed or crusted over (usually within six days after rash onset). Immunized children with mild infection with no crusts can be readmitted once no new red bumps have appeared for at least 24 hours.
- People with shingles or post-vaccination rash may attend school and child care if the rash is covered.
Role of teachers, caregivers, and family
- Encourage routine vaccination.
- Report the infection to the staff member designated by the child care program or school for decision-making and action related to the care of ill children.
- Notify staff members, students, and parents if a case is detected.