Provider-to-patient HIV transmission remains rare

CDC to release needle safety guidelines as well

While legislative and regulatory bodies focus on transmission of HIV from patients to health care workers, the public and media often have paid more attention to cases in which health care professionals infected patients with HIV, such as the 1990 case when a Florida dentist with AIDS infected six of his patients with HIV.

Despite the flurry of media attention that results when such cases occur, they remain very rare. In fact, the Atlanta-based Centers for Disease Control and Prevention (CDC) acknowledges only two instances worldwide when this has happened: the Florida dentist, and an HIV-infected French surgeon who evidently infected a patient during orthopedic surgery, according to a recent report in the Annals of Internal Medicine.1

It’s more common for patients to transmit the virus to providers. The CDC estimates that a health care worker’s risk of contracting HIV from a needle that contains the blood of an infected person is one in 200.

The CDC plans to release guidelines this fall that focus on prevention of needlestick injuries. The guidelines won’t offer advice about specific safety devices, but they will give providers some strategies to follow in developing their own prevention standards, says Denise Cardo, MD, chief of the CDC’s HIV Infection Branch and Hospital Infections Program.

"We’re trying to make a document to guide hospitals in how to select, implement, and evaluate prevention strategies," Cardo says. "We’ll give them a comprehensive plan for how to do that, including eliminating unnecessary use of needles, using devices with safety features, and educating staff on work procedures and prevention practices."

The guidelines also will provide background information on needlestick injuries, and they will show providers how to use their own surveillance data to make decisions about safety devices and practices.

"There are a lot of injuries occurring that could be prevented," Cardo says. For example, one study found that health care workers sometimes don’t know how to use new safety devices because hospitals haven’t properly trained staff in how to use the safety equipment.

Cardo says providers who want more information before the CDC’s guidelines are released can check with the Chicago-based American Hospital Association to see their guidelines, released in May, titled "Sharps Injury Prevention Program."

By focusing on preventing needlestick injuries, providers also will cut down on health care workers’ exposures to hepatitis, which lately has caused clinicians great concern because that virus is easier to transmit than HIV, says Julie Gerberding, MD, MPH, director of the hospital infections program for the CDC.

CDC statistics confirm 1,000 health care worker hepatitis B infections resulting from needlestick injuries and 54 health care worker HIV infections through occupational exposure. According to Gerberding, there have been 53 HIV-infected U.S. health care providers evaluated in retrospective studies, and these providers treated 22,759 patients — none of whom were determined to have acquired HIV from the infected provider.2

On the other hand, providers must protect themselves from needlestick injuries, which place them at risk of contracting HIV or other viruses, Gerberding says.

"I think the basic bullet message is this: Most exposures that lead to bloodborne pathogens are preventable, and the highest priority should be prevention," Gerberding says. "If the goal is to protect both patients and providers, the only situation [in which] the provider is likely to come into contact with the patient’s blood is through a needlestick injury."

The CDC doesn’t promote specific needle products, but safer needles clearly should play a role in preventing HIV transmission, Gerberding says. <3>Phlebotomist reused disposable needles

The possibility of providers transmitting HIV to patients has again jumped to the forefront of national concern because of an incident in which a phlebotomist at a SmithKline Beecham lab in Palo Alto, CA, admitted reusing disposable needles while working at the lab between June 1997 and March 1999. SmithKline Beecham officials sent letters to some 3,600 patients encouraging them to be tested for HIV and hepatitis. Patients already have begun filing lawsuits against the lab.3

The French case, by contrast, provided the first solid example of how a surgeon could transmit the virus during an operation. The French surgeon had apparently been infected with HIV from a needlestick injury while performing surgery in the early 1980s at a hospital in the Paris suburbs. His patient’s HIV status was unknown, and the patient later died. But the physician suffered a febrile illness of fatigue, weight loss, and rash shortly after that event.

The surgeon learned he was HIV-positive in 1994 after he was found to have HIV encephalo pa thy. Then, in 1995 — at the surgeon’s request — the French Ministry of Health offered HIV testing to patients on whom the surgeon had operated. Investigators used a CDC risk ascertainment questionnaire to interview the surgeon. They also reviewed the surgeon’s operating room practices and compared them with his peers. The surgeon had never received specific training about universal precautions, and he reported frequent opportunities for blood exposures, such as tightening suture wires with his fingers and tying sutures with the needle still attached.

Investigators found one of the surgeon’s former patients, a 70-year-old woman, who was HIV-positive. She had undergone a total hip prosthesis with bone graft in 1992. She tested negative for HIV prior to the surgery, and tested positive in 1994. There were no needlestick injuries or other potential exposures recorded in reports of her procedure. The woman’s viral sequences were significantly similar to the surgeon’s, and investigators concluded that she had been infected by the surgeon, probably due to some of his risky habits, including palpating sharp tips or pins.

[Editor’s note: To obtain a copy of the American Hospital Association’s 77-page book titled "Sharps Injury Prevention Program, a Step by Step Guide," contact AHA at P.O. Box 92683, Chicago, IL 60675; telephone: (800) 242-2626; fax: (312) 422-4505. The book costs $25 for AHA members and $75 for nonmembers.]

References

1. Lot F, Sequier JC, Fegueux S, et al. Probable transmission of HIV from an orthopedic surgeon to a patient in France. Ann Intern Med 1999; 130:1-6.

2. Gerberding J. Provider-to-provider HIV transmission: How to keep it exceedingly rare. Ann Intern Med 1999; 130: 64-65.

3. HIV, hepatitis tests urged for thousands after stunning admission of needle reuse. Hospital Infection Control 1999; 26:73-78.