Moving homeless in Tijuana may boost HIV risk-taking

The removal of homeless people from a section of Tijuana, Mexico, ostensibly for public safety purposes, may have increased high-risk behavior for HIV transmission in the area, researchers suggested.

After being forced by police from their usual dwellings near the United States border, homeless residents and people who inject drugs (PWID) increased risky behavior such as needle sharing, leading to HIV transmissions, the researchers wrote in Clinical Infectious Diseases.

“While well-intentioned, these changes in policy toward high-risk homeless and PWID living in the border region, and efforts to relocate and involuntarily commit individuals to rehabilitation, [have] driven some high-risk behaviors underground, where neither the government nor nongovernment organizations are able to provide adequate harm-reduction support such as needle exchange services,” researcher Sanjay R. Mehta, MD, of the University of San Diego departments of medicine and pathology, and colleagues wrote. “We believe these shifts led to increased risk-taking behavior, such as needle sharing, resulting in the observed outbreak.”

In 2015, Mexican authorities started to expand the San Ysidro border crossing. They began removing homeless people from the nearby area, known by locals as “El Bordo,” via police raids and patrols. They also demolished dwellings the inhabitants had built.

Many of those who were moved were placed in rehabilitation facilities against their wills, whereas others found new places to occupy and at times inject drugs, the researchers said.

To assess how the El Bordo removal may have affected HIV transmission, Mehta and colleagues analyzed data from eight studies conducted in Tijuana between 2004 and 2016. The studies involved HIV screening of 2,759 people. The populations included male clients of female sex workers (FSW), people in Tijuana with HIV, FSW themselves, FSW who injected drugs, PWID, FSW along with their noncommercial partners, prison inmates and men who have sex with men (MSM).

To establish HIV transmission patterns, the researchers analyzed HIV gene sequencing performed with blood samples from participants who were infected.

Interviews with recent seroconverters — those with a HIV seropositive test during study follow-up — were also conducted to gather information on risk behaviors before they seroconverted, as well as HIV treatment and challenges to accessing care.

According to Mehta and colleagues, 288 unique HIV gene sequences were obtained from individuals in Tijuana between 2004 and 2016, including 46.4% from MSM, 42.1% from individuals who reported transactional sex, and 27.8% from PWID. Some individuals had more than one risk factor, the researchers noted.

The researchers said that 42.4% of the sequences were linked to at least one other sequence, and 37 transmission clusters were formed.

Thirty-two individuals seroconverted during the observation period, the researchers said, including eight who seroconverted between April and July 2016. Three of these individuals were linked together, according to the results. Through qualitative interviews, the researchers found that changes in policing caused individuals to shift locations of residence and injection drug use, and increased their risk-taking.

“While only an association, we suspect that some of this mobility was reflective of the policing environment and more specifically, the policy shift toward removing the homeless from El Bordo and known shooting galleries,” Mehta and colleagues wrote.

They added that Mexico in 2014 switched from Global Fund aid of its HIV programs to government support as a middle-income country.

“This has led to widespread reports of shortages in sterile syringes and fewer condoms available to high-risk populations,” the researchers wrote. “The implications of such policy changes need to be carefully considered as significant downstream effects, such as increased HIV transmission, may occur.” – by Joe Green

Disclosures: The authors report no relevant financial disclosures.