Each day, Carrizo Springs city manager Terry McCalpin boils orange and lemon peels in a pot to make a supposed coronavirus preventative that’s been touted on social media. He drinks a tablespoon of the concoction, chasing it down with zinc, the blood pressure drug reserpine, and vitamin D3. McCalpin, a 58-year-old former police officer who describes himself as a “high-risk candidate for the virus” because of health problems, estimates that he’s been in close proximity to eight people with COVID-19 over the past year and a half without falling ill. 

Like most residents of rural Dimmit County, where Carrizo Springs is located, McCalpin is fully vaccinated. But a steady diet of online misinformation, and the continued proliferation of the virus, has convinced him the vaccine doesn’t work. “I did some research and started taking a couple supplements, and I believe this is why I’ve never contracted the virus,” he recently told me. (There is no evidence that McCalpin’s regimen has any efficacy against COVID-19.)

McCalpin’s fear of the virus is understandable. One in three Dimmit County residents have contracted COVID since the pandemic began—the highest case rate in Texas. Fifteen new cases are reported every day in the rural South Texas county of 10,124 people, and the test positivity rate is 23 percent, suggesting that the Delta variant is spreading rapidly. Around a third of the patients at Dimmit Regional Hospital have tested positive for COVID. But unlike in other parts of Texas, where the virus is surging and vaccination rates remain stubbornly low, Dimmit County residents, by and large, are fighting back. 

South Texas counties have embraced the COVID vaccines with more enthusiasm than any other part of Texas, and that’s true of Dimmit. Ninety-eight percent of its residents above the age of twelve have received at least one shot, and 66 percent are fully vaccinated—the fourteenth-highest rate in the state. From January to April, the Dimmit County Regional Hospital operated one of the state’s first major vaccination hubs, delivering more than 21,000 doses. Visitors came from other states, or crossed the border from Mexico, to get the jab. “People were going anywhere they could to get an appointment,” said hospital CEO John Graves. “If people wanted a vaccine, we gave it to them.”

Dimmit, like most other South Texas counties, is majority Hispanic and got hit hard early in the pandemic. Peter Hotez, dean of the School of Tropical Medicine at the Baylor College of Medicine, explained that many in the region are essential workers and live in multigenerational dwellings where the virus spreads more easily. Getting walloped by the first waves of COVID may have made those communities especially eager to get the vaccine. While the national vaccination rate among Hispanics slightly lags that of non-Hispanic whites (48 percent vaccinated versus 52 percent), the demographic is quickly catching up—Hispanics and Latinos account for more than a quarter of the Americans who have received their first shot in the past two weeks, according to CDC data, despite making up just 19 percent of the U.S. population. 

With its high infection and vaccination rates, Dimmit may be as close as any county in Texas to “herd immunity,” the point at which, in theory, a virus will no longer readily spread through a community. At the beginning of the pandemic, health experts said that America would need a 70 to 80 percent vaccination rate to reach herd immunity. Unfortunately, according to Hotez, the virulence of the delta variant means that communities now need a roughly 88 percent vaccination rate—a figure that will require that almost everyone twelve and older be vaccinated. 

Of course, no county is an island. Dimmit’s vaccination rate is high, but the majority of residents in nearby counties such as McMullen, two counties to the east, and Frio, which neighbors Dimmit to the northeast, are still unvaccinated. “What happens with this kind of infection is that it can really plow through adjacent areas, even if people are pretty well vaccinated,” Hotez explained. “If nearby areas have really high transmission, that’s going to affect you, unless you’ve got something like a ninety percent vaccination rate.” 

As the county waits to hit that threshold, some residents, such as McCalpin, have turned to unproven measures, while others are relying on standard mitigation strategies. Perhaps owing to the high infection rate, residents seem to have generally accepted masks, despite the skepticism of officials, including McCalpin, who doesn’t believe they work. Last month, the board of trustees of the Carrizo Springs Independent School District unanimously approved a mask mandate for all students, teachers, and staff, defying Governor Greg Abbott’s executive order banning such mandates. During my recent visit to Carrizo Springs, around two thirds of shoppers at H-E-B and Walmart were wearing face coverings. 

Tim Jarrett, the owner of Carrizo Springs Furniture, said around 90 to 95 percent of his customers wear masks. At the beginning of the pandemic, Jarrett installed hand sanitizer stations and plexiglass sneeze guards in his warehouse-like showroom. His employees regularly wipe down counters, doorknobs, and other touch points with Clorox. “We’ve had customers who have passed due to the virus,” Jarrett told me. Jarrett is fully vaccinated, as are all of his employees. “I didn’t make it mandatory, because I don’t feel like that’s my right. But I didn’t have any employees who were hesitant.” 

The small county is using its limited resources to fight the pandemic as best it can. Lacking a local public health department, it relies on Public Health Region 8 medical director Lillian Ringsdorf, who is based in San Antonio. (Ringsdorf is currently on leave and was unavailable for an interview.) Carrizo Springs, the county’s largest town, operates a free COVID-19 test site at a courthouse annex. 

On a recent Monday, I decided to get my own COVID test there. The annex was empty except for Ashley Mize, a 38-year-old pharmacy technician and Carrizo Springs resident who sat in front of a MacBook Air at a large desk, wearing a surgical mask and nurse’s scrubs. As I swabbed my mouth, Mize told me she’s been administering tests since the beginning of the pandemic, most recently for a company called All American Testing, which has contracted with Carrizo Springs. She spends Mondays, Tuesdays, and Fridays at the makeshift clinic, giving as many as a hundred tests a day.

Just that morning, Mize learned that her cousin, who also lived in Carrizo Springs, had died from COVID-19. “It’s hit home personally,” she said. “It’s definitely affected my family.” Still, Mize is one of the few eligible in the county who refuses to get the vaccine, which she believes hasn’t yet been proved safe. “I’m not trying to push anything into my body that doesn’t need to be there.” 

As I walked out of the clinic, I ran into a 76-year-old woman named Herlinda Perez sitting on a metal folding chair, wearing a mask and waiting for her turn to get tested. Perez is the pastor of Swindall Memorial United Methodist Church in nearby Crystal City. She typically leaves the senior care facility where she lives only to go to church or get groceries. During the pandemic she has limited services to no more than ten parishioners, who spread out on the pews; so far, nobody in her church has died of COVID. 

Despite receiving both doses of the Moderna vaccine in June, Perez had recently started experiencing worrisome symptoms: watery eyes, sneezing, coughing. It was probably allergies, but she decided to get a COVID test just in case. Dimmit County might be closer than anywhere in Texas to herd immunity, but residents continue to live in uncertainty. “My daughter said it’s the flu, but maybe it’s COVID,” Perez told me. “I hate that word.”