COVID-19 in migrating people at the US-Mexico border during Title 42 immigration restrictions

In March 2020, the US government implemented the policy of 'Title 42,' which restricted entry of asylum seekers on the stated basis of COVID-19 prevention. In the subsequent years, informal settlements for displaced persons developed and increased in size near the US-Mexico border. We sought to determine the risk of COVID-19 in this setting and compare this to nearby communities at the border.

We conducted an observational study of COVID-19 using data from a humanitarian relief operation at informal settlements at the US-Mexico border from March 2020 to March 2021. People who used this clinic had travelled through irregular routes of migration in Latin America. We reviewed patient characteristics, symptoms and point-of-care SARS-CoV-2 test results during the study period. We compared COVID-19 percent positivity in the camp with the surrounding communities in Mexico and Texas, USA, over 4-week periods.

In 6764 clinical encounters, there were 3737 SARS-CoV-2 tests completed with 482 positive results (12.9%, 95% CI 11.8% to 14.1%). Percent positivity was higher in people aged 30-39 years (16.5%) and 40-49 years (16.2%) compared with other age groups (p<0.001) and was 61.5% in pregnant women. Percent positivity was higher in asymptomatic people with suspected close contact exposures than in people with symptoms (15.2% vs 6.9%, p<0.001). Percent positivity was never higher in the camp than in the surrounding community in Matamoros, Tamaulipas, Mexico, and for 8 of the 13 4-week periods, not higher than in Cameron County, Texas.

COVID-19 percent positivity was typically lower or the same in this population of migrating people as in the surrounding communities, which provides further evidence against the use of pandemic-era immigration restrictions through Title 42.