Avon and Somerset Police has been accused of stigmatising people with HIV - after announcing it was going to issue spit guards to officers from the beginning of next year.
Senior officers - including the force's Assistant Chief Constable Stephen Cullen - said officers were at risk of contracting HIV, hepatitis and tuberculosis when they were spat at.
He made the comments last week, when the force announced there have been 79 assaults involving spitting since April.
From January officers will be able to use guards on suspects when they believe there is a risk of spitting.
A number of Bristol-based HIV support groups said they were upset by the comments made by the police at the launch of the scheme.
"It must be understood that HIV and Hepatitis C cannot be transmitted through spitting"
A spokesperson for , which has been campaigning on behalf of people with HIV for more than 20 years, said: "While we understand that being spat at can be distressing and supports the protection of police officers working on front lines, it must be understood that HIV and Hepatitis C cannot be transmitted through spitting. Suggestions to the contrary are not only incorrect, but are hugely damaging as they reinforce existing stigma and misconceptions that surround both viruses.
"Such falsehoods also cause unnecessary alarm to police staff. Given the significant challenges faced by police officers in the line of duty, causing them to fear they have been put at risk when they have not places an undue burden upon them, and must not go unchallenged. While the debate around the use of spit hoods is an important one for the police, policy-makers and the public, hepatitis C and HIV are of no relevance to it and should not be used as justification for their use."
The group went on to call for a public apology from the police, saying: "The largest challenges people living with HIV face are stigma, discrimination and misinformation about their condition which can often leave someone living with HIV feeling isolated and at worst can result in hate crime and violence.
"We are deeply concerned that a trusted source such as Avon and Somerset Police are publicly using such damaging falsehoods and about the negative affect that this will have on people living with HIV. We ask Avon and Somerset to make a public apology for using incorrect information to justify the use of spit guards."
"It takes me back almost 30 years when people were stigmatised for being HIV"
John, who was diagnosed as HIV 28 years ago, said: "The police must make a full public apology. It is simply not true to say that officers are at risk of contracting HIV or Hepatitis through saliva. That has never happened.
"It takes me back almost 30 years when people were stigmatised for being HIV. This is misleading information put out by the police - and can make people think they can catch things through saliva".
Avon and Somerset Police have Tweeted in response to the concerns.