The husband of a woman who was injected with a used needle while getting her Covid vaccine has spoken out about the ordeal. 

On Friday, a needle previously used to vaccinate one person was used again. 

Canterbury DHB senior responsible officer for the Covid-19 response, Dr Helen Skinner, said once staff at the Christchurch Hospital clinic realised the mistake, they immediately advised the second person. 

She said a comprehensive investigation into how the incident occurred is currently under way. 

The woman's husband, who wishes to remain anonymous, says they were both shocked. 

He said after the nurse administered the vaccine to his wife, she apologised saying she had realised it was a used one. 

The wife then waited the standard 30 minutes at the booth before her husband picked her up to go home. 

"When she told me, I was a bit confused. That normally never happens, how come this has happened?" 

She and her husband were nearly home when they received a phone call from the clinic saying they need to return to the hospital for a blood test. 

The blood tests came back clear yesterday afternoon. 

The husband says the news is a big relief for them both, as she was really stressed. 

He says they were told to expect the blood test results on Monday, yet the delay caused further concern for the family. 

"We're both really shocked. It shouldn't happen, the vaccination booth wasn't busy at all. I don't know how they made such a big mistake. 

"I am also really worried. We don't know what's going to happen and what problems could come with the situation." 

Skinner said the DHB is in contact with all three people involved and blood samples have been taken from those who received the injection. 

The DHB has apologised to both people. 

"We are doing everything we can to support all three people involved in this incident. We will continue to communicate with the person injected with a pre-used needle, supporting them and sharing any new information we receive. 

"We would like to thank the staff involved for their quick actions, open communication with everyone affected and their co-operation in the current investigation into this issue," she said. 

"If there are improvements we can make to our systems to reduce the chance of this happening anywhere else, we will certainly be implementing them."