Varicella Guidelines

General Guidelines

Individuals with varicella should not return to work until all lesions have dried and crusted, or if lesions do not crust, until no new lesions appear within a 24-hour period, as recommended by the Advisory Committee on Immunization Practices (ACIP) 1
Healthcare workers with active varicella must be excluded from duty until all lesions have dried and crusted, as per the ACIP guidelines 1
Healthcare workers exposed to varicella without immunity must be excluded from the 8th day after first exposure through the 21st day after the last exposure, as recommended by the ACIP 1

Immunocompromised individuals may have prolonged viral shedding and require longer exclusion, although the exact duration is not specified in the provided references
More extensive rash involvement may require longer isolation, although the exact duration is not specified in the provided references
Breakthrough varicella in vaccinated individuals is typically milder with fewer lesions but remains contagious, as noted by the CDC 1, 2

All lesions must be fully crusted, not just some, before returning to work to minimize the risk of transmission, as emphasized by the ACIP guidelines 1
Individuals with shingles are contagious from the appearance of the first vesicles until all lesions have dried and crusted, and no new lesions appear within a 24-hour period, which typically occurs 7-10 days from the onset of the rash, as stated by the Centers for Disease Control and Prevention (CDC) 1
The contagious period for varicella typically lasts from 1-2 days before the onset of the rash until all lesions are crusted, usually 4-7 days after the onset of the rash, according to the CDC and the American Academy of Pediatrics (AAP) 1, 2, 3

Healthcare workers with localized zoster and contained/covered lesions, who have been vaccinated against varicella, may return to work with lesions completely covered, as recommended by the CDC 1
Healthcare workers with localized zoster and unvaccinated against varicella must restrict from patient contact until all lesions are crusted, according to the CDC guidelines 1
Students with shingles should follow the same criteria as the general population, and all lesions must be dried and crusted before return, as noted by the CDC 1
For school-age children with lesions that can be completely covered, return may be permitted with strict adherence to keeping lesions covered, as recommended by the CDC 1

The CDC Advisory Committee on Immunization Practices recommends keeping all lesions covered with a bandage or clothing, avoiding direct contact with pregnant women who have never had chickenpox, and washing hands frequently to prevent transmission of the virus 1
The CDC Advisory Committee on Immunization Practices recommends the recombinant zoster vaccine (RZV) for immunocompetent adults aged 50 years or older, as well as for immunocompromised patients 19 years and older 4
Antiviral medications, such as acyclovir and valacyclovir, started within 72 hours of rash onset, can shorten healing time for herpes zoster, with a moderate strength of evidence, as recommended by the CDC 5
Early treatment with aciclovir, initiated within the first 24 hours after the onset of the rash, can reduce the duration of illness in immunocompromised patients, as recommended by the Infectious Diseases Society of America (IDSA) 6

The varicella rash appears after an average incubation period of 14-16 days (range: 10-21 days) following exposure, and infected individuals are contagious from 1-2 days before the onset of the rash until all lesions are crusted, typically 4-7 days after the onset of the rash, as recommended by the CDC and the AAP 1, 2, 3
The varicella rash progresses through a characteristic pattern, starting as macules that quickly progress to papules, vesicles, pustules, and finally crusts, with lesions more concentrated on the trunk and head than on the extremities, as reported by the AAP 2, 3
Varicella breakthrough disease (previously vaccinated individuals who develop varicella) has a milder clinical presentation, with a shorter duration (4-6 days), less fever, and typically less than 50 lesions, as recommended by the CDC 1, 2