Five children received incorrect immunizations during a "Shots for Tots" clinic that was operated by the Salem County Health Department at Memorial Hospital of Salem County in Salem, N.J.
Officials were executing an annual audit of the program, which provides vaccines for the uninsured, when it found the irregularities, according to a NBC10 report.
In one of the instances, a nurse was fired after giving a toddler a high dose of a cervical cancer vaccine.
Another instance involved a toddler receiving an expired vaccine, and another child received an immunization despite being younger than the drug's recommended age, according to CBS Philly.
Additionally, the audit found that $20,000 worth of vaccines had to be thrown away after not being refrigerated properly at the event.
The two registered nurses who ran the clinic through the county have resigned.
Memorial Hospital of Salem County released a statement to CBS Philly, saying the hospital "has no medical oversight of the clinic and the vaccinations. The hospital only provides space for the monthly event free of charge" to the county.