The kids, all from Tijuana, bused to the Mexican consulate in San Diego where they received the Pfizer vaccine from county nurses.

The goal of the pilot program, put on by a group in San Diego working with the San Diego County, is to vaccinate 450 adolescents ages 12 to 17 before ending in late December, according to The Associated Press. The children were chosen by Mexican social service organizations, like those that work with children whose parents were deported from the U.S.

Mexico has refused to vaccinate minors ages 12 to 17 partially because the government focused on older adults thought to be more vulnerable. The nation also has little vaccine supply for its minors. This month, the country is starting to prepare to vaccinate teens ages 15 to 17. Youths currently make up one-third of Mexico’s population.

Leslie Flores, 14, was one of the children who received a shot Thursday. She said although she was nervous, she is also happy about being vaccinated, the AP reported.

“Because this way I can protect myself and my family,” Flores said.

The county donated the vaccinations. In three weeks, the children will return for their second dose.

Carlos González Gutiérrez, the Mexican consul in San Diego, said that despite possessing a U.S. visa or passport, the minors couldn’t come to the U.S. for the vaccine until now because they had no adult to cross the border with.

Evaluation for the program will be conducted in early 2022 and officials will then determine if it is necessary to continue.

For more reporting from the Associated Press, see below.

Adrian Medina Amarillas, Baja California’s secretary of health, praised the effort.

“Baja California is experiencing a third wave” of infections, he said. “There is no doubt that this will help.”

Hundreds of parents in Mexico have taken legal action against the Mexican government to demand the right to be able to give the vaccine to their children. Overall, about 84 percent of Mexico’s adult population has had at least one dose of the vaccine.

The effort comes less than two weeks after the United States fully reopened its borders, and Mexican officials see it as another step toward ensuring the border stays that way. Border businesses were decimated by the 18-month closure to tourists and shoppers.

About 80 percent of the adult populations in both San Diego County and in Baja California have received at least one dose of the vaccine.

The first mass vaccination of Mexican minors happened last month along the Texas border when more than 1,000 children from the Mexican border state of Coahuila were bused to Eagle Pass, where they got their first shot of the Pfizer vaccine administered by members of the Texas National Guard. The youths ages 12 to 17 are the children of workers at border assembly plants known as maquiladoras.

In May and early June, more than 26,000 maquiladora workers in Baja California were vaccinated at the San Ysidro border crossing in San Diego.