Health care providers who prescribe postexposure rabies prophylaxis must confer with public health officials and obtain a confirmation code from the state health department before they can order doses of the vaccine because the only rabies vaccine available is in limited supply, the Centers for

An update on rabies vaccine availability posted on the CDC's Web site on Sept. 4 states that to obtain Imovax rabies vaccine, physicians must first contact a rabies state health official to conduct a risk assessment for the suspected exposure (a list is available online at www.cdc.gov/ rabies/staterabiespoclist.html). If a rabies postexposure prophylards is indicated, the state officials will provide physicians with a code to place on the Sanofi Pasteur rabies postexposure form, along with a required physician's signature. In early August, Sanofi Pasteur had announced that its rabies vaccine, Imovax, would not be available until mid-to-late 2009 because of renovations in its rabies vaccine production facility.

However, as of Aug. 29, Sanofi Pasteur, in coordination with the CDC, has resumed shipping Imovax rabies vaccine for postexposure prophylaxis only.

Novartis, the other leading manufacturer of rabies vaccine, will no longer be shipping supplies of RabAvert, and will be redirecting customers back to their state/local public health authorities to obtain a passcode to process their order through Sanofi Pasteur.

"Judicious and appropriate use of rabies vaccines is crucial to avert a situation in which persons exposed to rabies are put at increased risk due to depleted vaccine supplies," the CDC statement said.

Novartis is requiring that providers obtain the confirmation code to ensure that thorough risk assessments are done before ordering vaccine for postexposure prophylaxis, according to the CDC. "These codes should only be released by a state/local health authority that has reviewed the known facts of a given exposure and determined they indicate a sufficient level of exposure risk" as described in the CDC's Advisory Committee on Immunization Practices (ACIP) recommendations on preventing human rabies. which were updated earlier this year.

The CDC said the new requirements will remain in place until vaccine supplies are adequate.

In May, the CDC announced that vaccine would temporarily be unavailable for preexposure prophylaxis.

The current statement says that until supplies are adequate, distribution of rabies vaccine for preexposure prophylaxis will require approval from state and federal public health authorities, with priority given to workers in rabies laboratories, animal control officers, veterinary staff. wildlife workers, and other people at risk for occupational rabies exposure, according to the CDC.

The CDC statement also points out that while people with a possible exposure to rabies need to be evaluated as soon as possible and that postexposure prophylaxis (PEP) is an "urgent medical issue," it is not considered an emergency, and PEP can be delayed until after the animal has had rabies testing "or clinical observation is completed," an approach that "not only limits administration of PEP to persons with confirmed rabies exposure, but it is also cost saving and conserves limited resources."

A national working group has been formed to monitor the supply situation and provide updated recommendations "as the situation evolves," the CDC said.

ACIP's recommendations are available at www.cdc.gov/mmwr/preview/mmwrhtml/ rr5703a1.htm.

More information on rabies as well as updates on the vaccine supply can be obtained from state or local public health officials, or from the CDC at 800-232-4636 or www.cdc.gov/rabies

BY ELIZABETH MECHCATIE

Senior Writer