Detecting HIV in the acute stage is important because patients are highly infectious at that time and may spread the infection unknowingly. “Diagnosing HIV at the acute stage can also lead to earlier treatment, which in turn can improve patient health and decrease risks for further transmission,” says Michael S. Lyons, MD, MPH. However, it can be difficult to detect HIV in the acute stage because symptoms do not stand out. In addition, the least expensive and most commonly used HIV tests often miss acute HIV.

Research indicates that screening for HIV in EDs is important but controversial. This is because EDs are already overwhelmed and do not historically participate in prevention interventions. Resistance to adding HIV screening services in the ED is likely to be greatest in geographic areas of low HIV prevalence. “If acute HIV is seen more commonly than expected in EDs—even in areas of lower prevalence—then we should be motivated to do more HIV screening,” says Dr. Lyons. “We should also strive to use the best screening technology that is currently available.”


Exploring the Issue

For a study published in the American Journal of Public Health, Dr. Lyons and colleagues sought to better understand how many ED patients have undiagnosed HIV in the acute stages of infection. A cross-sectional seroprevalence study was conducted, enrolling 926 randomly selected adults (ages 18 to 64) from an urban ED in an area of low-to-moderate HIV prevalence.

According to the results, the overall prevalence of undiagnosed HIV was 0.76%, amounting to seven cases in total. While there were few cases overall, a surprisingly high percentage of these—nearly half—were in the acute stages of infection before the subjects had developed an antibody response. This means that they would not have been detected by usual antibody tests and could only have been detected with more advanced tests that can detect virus particles. “Because we’re located in a lower prevalence area and because the duration of acute infection is very short,” says Dr. Lyons, “we expected that we wouldn’t find any cases of acute HIV, but we essentially found the opposite.”

Significant Implications

The high proportion of acute HIV cases seen in the study suggests that EDs may be even more important for HIV screening than previously thought, says Dr. Lyons. “The identification of acute HIV in ED settings should be a greater priority, even in regions of lower HIV prevalence. There is still work to be done to balance the tradeoffs for screening in low prevalence areas, but missed opportunities are particularly damaging to patients and overall public health. Our findings point to the urgent need for growth in large-scale ED screening practices and warrant further investigation.”