According to the American Academy of Dermatology, herpes zoster results from reactivation of the virus that causes chicken pox within clusters of sensory nerve roots called ganglia. People with herpes zoster can spread the virus to non-immune people, resulting in chicken pox. The Centers for Disease Control and Prevention recommend airborne precautions under certain circumstances to control the spread of the virus to non-immune individuals through infectious aerosols created when an infected person talks, breathes or coughs. Due to the requirement for specialized equipment, airborne precautions can only be completely observed in health care settings.
Airborne precautions shouldn't be applied to all patients with herpes zoster, notes the Centers for Disease Control and Prevention. The indications for airborne precautions include immune system problems, such as AIDS or leukemia, and widespread rash. People with one or both of these conditions are presumed to circulate the virus through their respiratory and salivary secretions, hence the need for airborne precautions. Airborne precautions can be discontinued when skin lesions due to herpes zoster crust because, according to the CDC, crusting signals that a person is no longer contagious.
N95 Respirator Masks
The CDC recommends a mask with a rating of "N95" or higher to control the spread of the virus that causes herpes zoster and chicken pox. Non-immune caregivers and contacts should wear the mask when entering the sick room. Sick people should wear the mask when they leave the sick room. Since the effectiveness of any respirator depends on the seal between the skin and the mask, the CDC recommends "fit-testing" to assure a good fit and provide training on the proper application of the mask. An infection control nurse will typically perform the training using non-infectious scent molecules that cannot be detected if the mask fits properly.
Airborne Infection Isolation Room
The CDC defines an airborne infection isolation room, or A.I.I.R., as a single patient room equipped with air handling and ventilation features that meet standards set forth by the American Institute of Architectects' Facility Guidelines Institute. Specifically, the room must be designed to maintain air pressure that is less than that of surrounding rooms and hallways, so that air is drawn in when the door is opened, rather than out. Air must exchange six to 12 times each hour, either with fresh, outdoor air or air circulated through a special filter. When an A.I.I.R. is not available, the CDC stipulates that a patient must be transferred to a facility that does have an A.I.I.R.
Some of the infections, including herpes zoster and chicken pox, that necessitate airborne precautions can't be transmitted to people who are already immune due to previous exposure or vaccination. Where possible, the CDC recommends designating these immune personnel to care for patients. In the case of herpes zoster, the CDC requires health care workers to document immunity through pre-employment blood tests for antibodies, followed by vaccination in those who aren't immune. So, designated personnel is rarely a problem in the case of airborne precautions for herpes zoster.