Humans who contract rabies may be in a tight spot for the near-term.

The supply of human rabies vaccine for post-exposure prophylaxis (PEP) is severely limited and is now only available through Sanofi-Pasteur, according to a notice on the U.S. Centers for Disease Control and Prevention’s website.

The CDC issued a notice on its website in late August saying that the supply of human rabies vaccine for PEP is “being used at a higher rate than expected, which may affect the near-term availability of [the] vaccine.”

Originally, Novartis, which manufactures the RabAvert rabies vaccine, was the only company that had any of the PEP vaccine available. But in a letter to its customers dated Aug. 28, Novartis now says it will not accept new orders for RabAvert except under certain conditions.

“Over the past several weeks, there has been further constraint to the nationwide supply of rabies vaccine as the other manufacturer for the U.S. market was unable to supply vaccine,” the letter says.

Sanofi Pasteur announced in August that its IMOVAX rabies vaccine would not be available at all until later this month or even into October.

Although Sanofi Pasteur has resumed shipping the vaccine, it is requiring medical care providers get a “pass code” from their rabies state health official in order to secure an order. The code will ensure that adequate local exposure assessment has taken place.

“If your Rabies State Health Official determines that post-exposure prophylaxis is required, they will provide you with a pass code to place on the Sanofi Pasteur Rabies Post-Exposure Form,” the CDC notice says.

Novartis said it anticipates RabAvert will be available again in October. Until then, the vaccine is only available for lab-confirmed cases of rabies, and those orders also require a pass code from the rabies state health official.

Until now, Sanofi Pasteur had not been able to keep up with demand for its IMOVAX vaccine, in part due to decreased production caused by renovations to its facility in France, according to the CDC. The new facility is expected to be ready in mid- to late-2009.

In addition to the PEP vaccine shortage, the supply of pre-exposure prophylaxis (PrEP) rabies vaccine is also very limited. The CDC says the rabies PrEP vaccine “will be distributed on approval from state and federal public health authorities for those first responders with a critical need and in consideration of available supplies.”

Until vaccine supplies are back up to normal, veterinarians and their staff should take extra precautions to avoid exposure to rabies, and make sure to educate their clients who might be at risk. If human exposure is suspected, according to the CDC, treatment “can be delayed until animal rabies testing or clinical observation is completed. This approach not only limits administration of PEP to persons with confirmed rabies exposure, but it is also cost-saving and conserves limited resources.”

In other rabies news

A horse that was shown at the Missouri State Fair died of rabies Aug. 19, according to a state news release. The two-year-old bay gelding died two days after he began showing signs of the disease. The Missouri Department of Health and Senior Services said people who attended the fair and may have had contact with the horse should see their doctor.

The second annual World Rabies Day is Sept. 28. World Rabies Day is an initiative by the Alliance for Rabies Control, a global group of researchers and professionals who want to promote rabies awareness. Events are planned around the globe, including free vaccinations, education programs and footraces to benefit the organization.