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Medics and volunteers are working all across the county to encourage those without a fixed address to protect themselves against the virus.
Sessions have been taking place at the headquarters of the charity Shelterbox in Truro.
Gill Emerson, from the NHS vaccination team, said: "A lot of people are frightened of the vaccine, frightened of needles. So we just work to put them at ease, and provide the service we can for them.
"We cannot coerce them, we will never force anybody into having a vaccine. That's not what we're here for."
The sprawling geography of Cornwall means some people can be hard to get to - and not just physically.
"Some of the more vulnerable people in west Cornwall, in places like Camborne where we know there is a vast proportion of the population who haven't obtained the vaccine, we are doing outreach work to those areas as well.
"But it's a service, we're not going round dragging people out of houses and vaccinating them.
"Some people just need a bit of reassurance. It is a safe vaccine or we wouldn't be providing it."