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A transplant patient who took medication to suppress his immune system said he felt worried about staying safe from Covid as the world opened back up.
Hal Cohen had a second kidney transplant 18 months ago and spent a year shielding during lockdown.
He had both his coronavirus jabs but because of his condition doesn't know how well they have worked.
"I have to take a lot of medication that suppresses the immune system so I have to be really careful about getting infections," Hal told ITV News London.
"It's really unclear to me what I can do. Can I go to things with my kids and wife that are indoors? Can I get on public transport? Can I go to work?
"It seems right now from those two jabs that I don't have an antibody response so it's really unclear for me whether I've got any protection from coronavirus," he added.
Hal believes transplant survivors should be prioritised for trials looking at the effectiveness of having a third vaccine dose.
But experts said that antibody levels are not the only way of measuring whether or not the first two have worked.
"Just because someone didn't respond quite as well with a an antibody level in their second dose doesn't mean they'll do any better in their third dose," said Professor Robert Read from the Joint Committee on Vaccination and Immunisation.
"The other thing that just measuring antibodies doesn't give you necessarily the whole story, there may be other things that need to occur in the body to give you natural protection," he added.
Charity Kidney Care UK said protection also needs to come from the Government.
"First of all the clarity of the messaging to people, the continuing need to take care. Second, advice to employers so that even if social distancing finishes after June 21st, to continue to be able to protect and mitigate for people," said the charity's Fiona Loud.
The Government says it has now fully vaccinated 65% of clinically vulnerable people.But Hal and his family say they still don't know whether he is protected enough.