That's the promise of a new first-of-its-kind, statewide N.C. Department of Health and Human Services effort that may become a model for cutting HIV transmission and saving lives across the nation. A news report on the program appears in this week's (May 28) issue of the Journal of the American Medical Association.
Designed and tested by University of North Carolina at Chapel Hill medical scientists together with state public health officials at HHS, the Screening and Tracing Active Transmission (STAT) program began quietly in November, its developers say, and is only now being publicly announced.
"Testing strategies employed in the program are already used by the nation's blood banks for screening donated blood," said Dr. Christopher Pilcher, chief program developer. "When used to enhance testing, the procedures are proving to be a distinct improvement over standard antibody tests. This is because antibody assays cannot detect the virus for up to two months post-infection and therefore miss the earliest, most infectious period when carriers can spread the virus before they even know they have it.
"The acute stage of the infection is almost never diagnosed in clinical practice and is always missed by routine antibody tests," said Pilcher, assistant professor of medicine at the UNC School of Medicine. "So we have always missed the diagnosis at the time when we know that people have by far the most virus in their blood and are at their most infectious. In fact, when these patients got tested in the past, they would receive a falsely reassuring negative test result. If we can catch infected people during the first weeks when routine antibody tests are still negative, the recently infected men and women can then avoid unknowingly spreading HIV to their husbands, wives, unborn children or other intimate partners."
In the program's first six months, the very recent HIV infections identified in North Carolina's health departments and public testing sites have resulted in a 4 percent increase in the total number of new HIV diagnoses made in the state, Pilcher said. Overall, 17 cases of acute HIV have been identified by the STAT program, and the majority have been successfully entered into care.
Costs associated with the added testing are low -- about $2 per test, or a little over $4,000 for each new case diagnosed, figures that pale by comparison with the financial and human burden of missing a case or missing the opportunity to prevent further HIV transmission.
An additional feature of the program is a rapid response team of about a dozen public health specialists deployed across North Carolina and responsible for contacting, counseling and getting patients into care and prevention services.
"The ability to get people in for urgent evaluation is a really important part of the overall program," Pilcher said. "You can't have testing without the counseling."
A pilot study demonstrating the approach's preliminary success and promise appeared in JAMA last year. Besides Pilcher, UNC authors of the pilot study were Drs. Peter A. Leone and Joseph J. Eron of medicine, Marlene Smurzynski of epidemiology and Drs. Amy L. Peace-Brewer and Susan Fiscus of microbiology and immunology. Other authors were J. Todd McPherson and Juanita Harris of the N.C. State Laboratory of Public Health's Serology/Virology Laboratory, Leone and Judy Owen-O'Dowd of the N.C. Department of Health and Human Services' HIV/STD Prevention and Care Branch and Dr. Charles B. Hicks of Duke University's Department of Medicine.
Under the STAT program, patients asking for an HIV test still receive a routine antibody test. Specimens also are tested individually through what's called polymerase chain reaction (PCR).
"So far, we have tested about 50,000 patients, and the most important thing we have observed is that a significant number of very contagious infections are right now being missed by routine antibody testing," Pilcher said.
In addition, he said, patients can potentially benefit themselves if doctors know to start them quickly and aggressively on anti-retroviral treatment. Several preliminary studies have shown recently that early treatment may improve their long-term prognosis.
The detection of acute HIV infections can have important public health benefits as well, Pilcher said.
"Having the means to distinguish newly infected from long-ago infected individuals can reveal actual populations getting infected in something like real time and can provide guidance and feedback to the state's HIV prevention efforts."
Other medical scientists had suggested that the pooling technique could uncover individual new acute HIV cases among large groups of at-risk people, but the UNC investigators and their colleagues were the first to try the idea.
Other states have expressed interest in conducting similar screening. According to the JAMA article, the U.S. Centers for Disease Control and Prevention will award grants before long to study the feasibility of wider RNA screening across the country.
Note: Pilcher can be reached at (919) 966-2536 or (919) 216-3692 (pager).
Contact: David Williamson, (919) 962-8596
By DAVID WILLIAMSON
UNC News Services
Journal
JAMA