Can geospatial mapping fill in the gaps in areas lagging behind in global efforts to end the HIV epidemic?
That’s what Diego Cuadros, PhD, assistant professor of health geography and disease modeling at the University of Cincinnati, set out to learn using geospatial data combined with prevalence data to identify the most underserved areas in Sub-Saharan Africa (SSA) for HIV services.
Study findings, which were published Nov. 24 in PLOS Global Public Health, highlight that as many as 1.5 million people living with HIV (PLHIV) in SSA have more than an hour’s motorized travel time both ways to access care, while roughly 3 million must set aside, at minimum, 30 minutes. When the only mode of transportation is walking, as much as 95.3% of underserved areas are faced with at least 30 minutes travel time.
This is simply the tip of the overall problem, Dr. Cuadros told this news organization.
“We are able to estimate how many people [whose] quality of life is being affected by HIV because they are not on treatment and most probably, HIV incidence is high in those areas. But [it’s not as simple as just] increasing the number of health care facilities,” he said. “We need to find strategies to be able to cover this population.”
Dr. Cuadros also noted that the problem goes both ways. “It’s hard for them to move, and it’s [also] hard to reach them,” he explained.
Mapping care, or lack thereof
Dr. Cuadros and team used two primary sources of data to generate high-resolution maps of underserved SSA areas: estimated number of PLHIV between the ages of 15 and 49 years in 47 SSA countries paired with population density and global map of travel time to the nearest health facility by motorized and nonmotorized (that is, walking) transportation. Combining these data allowed them to then detail the distance from access to care for every 5 km².
The mapping exercise showed that 90.5% of the total territory, in which about 7 million PLHIV resided, had more than 10 minutes motorized travel time to the nearest health care facility, while 74.6% were within 30 minutes, and 58.9% were within 60 minutes. Increases in threshold travel times (from 10 to 60 minutes) corresponded directly to declines in the average proportion of underserved areas (from 80.9% to 42.6%). However, in certain countries like Sudan and Mauritania, 99.4% of the areas were underserved at the 10 minute threshold, while more than 90% were underserved at the 60 minute threshold.
Corresponding rates for nonmotorized access to health services were similar: 88.7% (~17.6 million) PLHIV had 10 minutes walking time to health care services, while 57.8% (~11.5 million) had at least 30 minutes, and 33.0% (~6.6 million), at least 60 minutes. Likewise, as threshold times increased from 10 to 60 minutes, the percentage of affected PLHIV declined (to roughly 50% in two-thirds of the countries). But more than 70% of PLHIV resided in underserved areas in countries like Equatorial Guinea, Eritrea, South Sudan, and Sudan.
Geographical allocation of health service facilities underscores treatment gaps
“We think that most PLHIV live in urban areas or close to urban areas, and most of the health care facilities in Africa are concentrated in those areas. But [roughly 8 million people with HIV] are living in rural areas, and for most, movement is very difficult,” explained Dr. Cuadros, meaning that the majority are not on treatment despite the high incidence of HIV.
Inarguably, the pandemic has interrupted HIV services and treatment substantially on the African continent, further challenging any efforts to translate these study findings into actionable strategies.
“We’ve known for quite a while that distance and travel times and travel expenses are known risks for nonadherence, for lack of access to diagnostics, for people at risk for exposure,” Chris Beyrer, MD, MPH, Desmond M. Tutu Professor of Public Health and Human Rights at the Johns Hopkins Bloomberg School of Public Health, Baltimore, said in an interview. (Dr. Beyrer was not involved in the study.)
“What’s new is the ability to really look at this across geographies and really home in on how many people face very long times and distances for travel. That’s a really important contribution,” he said.
Dr. Cuadros pointed out that these hard-to-reach populations are key to achieving the UNAID’s HIV elimination targets. “We’re going to have these pockets of transmission that are going to be really important for epidemic control,” he explained.
Toward that end, the onus appears to extend well beyond solutions that emphasize difficulty in reaching people from the provider perspective. “There’s quite a lot of what you might want to think of as blaming the victim for when people miss appointments, don’t appear to be adherent, [or] can’t stay reliably suppressed,” said Dr. Beyrer.
“It’s really important for providers in general to include in history and intake how far people have come, what their challenges are with travel, to really pay attention to those issues. Having this elegant analysis, this level of detail, is an important first step,” he added.
Dr. Cuadros has disclosed no relevant financial relationships. Dr. Beyrer reports a consulting agreement with Merck.
A version of this article first appeared on Medscape.com.