More than 2,500 people in Wiltshire have been referred to a special medical unit dealing with long Covid and its mental health impacts.
Carol Langley-Johnson, from Wiltshire Health and Care partnership, said people's health has been severely impacted by the pandemic and lockdowns.
The unit opened two years ago and serves Bath, Swindon and Wiltshire.
In a 2020 survey, 55% of Swindon residents reported worsening of mental health as a result of the pandemic.
Ms Langley-Johnson told councillors on Swindon Borough Council's adults' health, care and housing overview and scrutiny committee that this rose by another 2% in 2021, according to the Local Democracy Reporting Service (LDRS).
She said: "We now have two years of data, and the unit has seen about 2,500 people, including 635 people in Swindon, and is getting about 25 referrals a month from the borough."
Ms Langley-Johnson added that in both surveys carried out younger people, people who lost their job or were unemployed, people with long term health conditions, those who were classified as clinically extremely vulnerable or were living with someone classified as clinically extremely vulnerable were more likely to report a worsening of their mental health.
Loneliness, uncertainty, anxiety and depression all took their toll during the years 2020 and 2021, she said.
In Swindon a six week programme designed to target common symptoms of long Covid, such as cognitive dysfunction, fatigue, breathlessness and pain, has been set up.
The programme includes activity management and energy conservation, managing unhelpful thoughts that impede rehabilitation and recovery, stress management and relaxation training.
"Uncertainty for the future was a cause of concern for many respondents in the survey," Ms Langley-Johnson added.
"The impact of isolation and loneliness were juxtaposed with the threat of getting ill or spreading the virus through resuming normal activities and socialising with others."
She added that Covid-19 also affected people's cognitive ability.
"We see a large proportion of people come in with "brain fog" presenting almost like a brain injury not just anxiety and depression."
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