A blue-line Valley Transit Authority (VTA) light rail arrives at the San Antonio Station in San Jose, Calif., on Oct. 6, 2021. (Harika Maddala/ Bay City News)

The Santa Clara Valley Transportation Authority will require its employees and contractors to prove that they have completed their initial vaccine series, the agency said Thursday.

The policy requires the VTA’s more than 2,000 employees and contractors to prove by April 29 have at least received their first two mRNA vaccine doses or single Johnson & Johnson vaccine dose.

According to the VTA, workers will not be required to prove that they have received a booster dose, which health officials have argued is necessary to bolster immune response against COVID-19.

“We have a responsibility to protect our employees and the public and help bring an end to this devastating pandemic,” VTA General Manager and CEO Carolyn Gonot said in a statement.

Roughly 60 percent of the VTA’s workforce has already voluntarily confirmed their full vaccination status, according to the agency. That figure does not include employees hired after Aug. 1, 2021, who are required to be vaccinated.

Unvaccinated employees will be allowed to request a medical or religious exemption to the vaccination requirement.

Those with approved exemptions will be required to test weekly for COVID. All others whose exemptions are not approved must complete their first vaccine series by the April 29 deadline.