Recommendations for Prevention of HIV Transmission in Health-Care Settings [MMWR Vol. 36. No. 2S]

August 21, 1987 - Supplement

Instruments or devices that enter sterile tissue or the vascular system of any
patient or through which blood flows should be sterilized before reuse. Devices or
items that contact intact mucous membranes should be sterilized or receive highlevel disinfection, a procedure that kills vegetative organisms and viruses but not
necessarily large numbers of bacterial spores. Chemical germicides that are registered with the U.S. Environmental Protection Agency (EPA) as "sterilants" may be
used either for sterilization or for high-level disinfection depending on contact time.
Contact lenses used in trial fittings should be disinfected after each fitting by using
a hydrogen peroxide contact lens disinfecting system or, if compatible, with heat
(78 C-80 C [172.4 F-176.0 FJ) for 10 minutes.
Medical devices or instruments that require sterilization or disinfection should be
thoroughly cleaned before being exposed to the germicide, and the manufacturer's
instructions for the use of the germicide should be followed. Further, it is important
that the manufacturer's specifications for compatibility of the medical device with
chemical germicides be closely followed. Information on specific label claims of
commercial germicides can be obtained by writing to the Disinfectants Branch, Office
of Pesticides, Environmental Protection Agency, 401 M Street, SW, Washington, D.C.
20460.
Studies have shown that HIV is inactivated rapidly after being exposed to
commonly used chemical germicides at concentrations that are much lower than
used in practice (27-30). Embalming fluids are similar to the types of chemical
germicides that have been tested and found to completely inactivate HIV. In addition
to commercially available chemical germicides, a solution of sodium hypochlorite
(household bleach) prepared daily is an inexpensive and effective germicide. Concentrations ranging from approximately 500 ppm (1:100 dilution of household
bleach) sodium hypochlorite to 5,000 ppm (1:10 dilution of household bleach) are
effective depending on the amount of organic material (e.g., blood, mucus) present
on the surface to be cleaned and disinfected. Commercially available chemical
germicides may be more compatible with certain medical devices that might be
corroded by repeated exposure to sodium hypochlorite, especially to the 1:10
dilution.
Survival of HIV in the Environment
The most extensive study on the survival of HIV after drying involved greatly
concentrated HIV samples, i.e., 10 million tissue-culture infectious doses per
milliliter (31). This concentration is at least 100,000 times greater than that typically
found in the blood or serum of patients with HIV infection. HIV was detectable by
tissue-culture techniques 1-3 days after drying, but the rate of inactivation was rapid.
Studies performed at CDC have also shown that drying HIV causes a rapid (within
several hours) 1-2 log (90%-99%) reduction in HIV concentration. In tissue-culture
fluid, cell-free HIV could be detected up to 15 days at room temperature, up to 11 days
at 37 C (98.6 F), and up to 1 day if the HIV was cell-associated.
When considered in the context of environmental conditions in health-care
facilities, these results do not require any changes in currently recommended
sterilization, disinfection, or housekeeping strategies. When medical devices are
contaminated with blood or other body fluids, existing recommendations include the
cleaning of these instruments, followed by disinfection or sterilization, depending on
the type of medical device. These protocols assume "worst-case* conditions of

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