This is a regular verb. It follows the conjugation pattern of the verb falar.
Present:
A Ana vacina pacientes na clínica.
Ana vaccinates patients at the clinic.
Preterite:
O Miguel vacinou o cachorro dele na semana passada.
O Miguel vacinou o cão dele na semana passada.
Miguel vaccinated his dog last week.
Conditional:
A Clara vacinaria todos se fosse possível.
Clara would vaccinate everyone if possible.