A police force is to introduce spit guards after the number of assaults against officers doubled.
Avon and Somerset Police will roll out spit guards to all operational officers from January next year, following training.
Four officers were spat at last week, while 79 assaults against officers at the force since April have involved spitting.
The spit guards will only be used when a person threatens to spit, has attempted to spit or has already spat.
Spit guards - already used in 25 other forces - will only be used when an officer's body worn camera is switched on.
Assistant Chief Constable Stephen Cullen said: "The increase in reports of spitting against our officers has convinced us that we need spit guards to protect ourselves.
"Each day we face being spat at, putting us at risk of HIV, hepatitis and tuberculosis and the degrading assault can have a lasting psychological impact.
"Only last week a woman with hepatitis C was spitting infected blood and saliva at four female officers as they looked after her for 11 hours in custody.
"The only protection currently available was riot helmets to protect their faces.
"We believe our officers should have the right kit to do their job and this includes spit guards. We also hope their introduction will deter people from spitting at police officers in the first place."
Use of spit guards will be recorded and the data will be made public.
The Police and Crime Commissioner's Scrutiny of Police Powers Panel - made up of local people - will also review the use of spit guards as part of their quarterly meetings.
A spokesman for Avon and Somerset Police said spit guards will be rolled out once officers have completed their training.
The decision to introduce the device is part of the force's support for the Police Federation's proposed Assault on Emergency Workers (Offences) Bill.
Vince Howard, chairman of Avon and Somerset Police Federation, said: "We are pleased to see the introduction of spit guards for front line officers.
"This option affords those officers, who are increasingly subject to this abhorrent act, the opportunity to protect themselves from the risks of serious communicable diseases.
"This is a protection and prevention measure and we welcome the support offered by the Constabulary in making this equipment available."
Data for spitting incidents reported on the Welfare Information Form shows that there have been 79 spitting incidents out of 487 recorded assaults since April.
A force spokesman said this was a large increase on previous reports, adding that the number of assaults on officers doubled between 2014 and 2017.