They're now being tested for HIV and

Dozens of co-workers are being screened for HIV and hepatitis after a nurse was found reusing a syringe to administer flu shots.

Employees at Otsuka Pharmaceutical, who received the vaccination at their offices in Princeton, New Jersey on September 30, have been warned they may have been exposed to 'infected blood.'

Almost 70 patients have now been called in for testing but face a long, anxious wait as it can be months before serious infections such as HIV show up in blood work.

Healthcare provider TotalWellness confirmed that the nurse contracted to carry out the flu shots had 'failed to follow proper medical procedures and safeguards.'

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Dozens of co-workers are being screened for HIV and hepatitis after a nurse was found reusing a syringe to administer flu shots

Employees at Otsuka Pharmaceutical (pictured) in Princeton, New Jersey, who received the vaccination on September 30 have all been warned they may have been exposed to 'infected blood'

Officials have not yet revealed whether disciplinary action will be taken against the nurse.

The New Jersey Department of Health sent out letters to the 67 pharmaceutical co-workers two days after the vaccinations to warn them that the syringe 'was reused multiple times', NBC 10 reported.

While the letter said the risk of contamination was low, it urged those affected to seek testing for hepatitis B, hepatitis C and HIV.

'Syringe reuse may have exposed you to infected blood,' the letter stated. 'At this time NJDOH is not aware of any disease transmission, but you may be at risk for developing an infection as a result of this improper practice.'

Courtesy NBC10

TotalWellness, who contracted the nurse to carry out the flu vaccinations, confirmed that the nurse had 'failed to follow proper medical procedures and safeguards'

The company, which states that it runs onsite flu shot clinics which mean less doctor visits and sick days for staff, are now offering free blood tests

The Department of Health said that the nurse had changed the needle between each injection, but re-used the same syringe each time.

Both the needle and syringe should be only ever be used once and disposed of, added Jill Swanson, West Windsor Health Officer.

Free blood tests are now taking place for the employees at the West Windsor Township Senior Center, run by the Centers for Disease Control and Prevention (CDC), in partnership with the Health Department and TotalWellness.

Patients must then be re-tested in four to six months before they can be given a clean bill of health.

One Otsuka Pharmaceutical employee told NBC News that having to wait so long for the results was giving her 'incredible anxiety.'

Officials investigating the incident also found that the nurse also gave less than the recommended dose of flu shot at the Mercer County clinic.

The Department of Health warned that anyone wanting to be protected against flu this winter would need to have another vaccination.

Dozens of co-workers are being screened for HIV and hepatitis after nurse was found re-using a syringe to administer flu shots. Jill Swanson, West Windsor Health Officer, (pictured) warned both the needle and the syringe should only ever be used once and disposed of during vaccinations

Free blood tests are now taking place for the employees at the West Windsor Township Senior Center, run by the Centers for Disease Control and Prevention (CDC) , in partnership with the Health Department and TotalWellness

A spokesperson for TotalWellness said the company was 'dedicated to ensuring all participants receive any and all appropriate screenings, care and counseling until this matter is resolved.'

Otsuka Pharmaceutical were unavailable for comment.

It is not the first time a medical blunder has potentially put lives at risk.

In 2014, more than 4,000 patients were warned they could have been exposed to HIV and hepatitis at a New York hospital after insulin pens used to treat diabetes were reused on more than one person.

South Nassau Communities Hospital in Oceanside on Long Island, near New York City, said 4,200 patients may have received insulin from the pens - not a single-use disposable needle - that could have been used on more than one patient from as far back as 2011.

'The risk of infection from this is extremely low,' the hospital said in a statement, adding it was recommending patients 'be tested for hepatitis B, hepatitis C and HIV.'

When asked if anyone was confirmed to have been infected a hospital spokeswoman said 'not to my knowledge.'