Almost three quarters of health charities across Scotland have warned they have no funding beyond this month and may have to close. According to a survey of 65 local and national voluntary organisations such as DeafBlind Scotland, some 72% expect to shut their doors within weeks.

The study warns that unless the funding issue is resolved hundreds of jobs and thousands of services for some of the most vulnerable people in the most disadvantaged communities will be lost.

Among those who will lose services are 100 people with Hep C or HIV, 300 children and parents and 400 mental health clients.

Around 189 staff in 20 organisations have already lost jobs or been given redundancy notices. A further 11 organisations facing closure have not yet issued redundancy notices so the total jobs lost is expected to be higher. It is the first concrete evidence of the squeeze on the voluntary sector predicted last year following the Scottish Government's concordat with local authorities, which delivered a key SNP manifesto pledge to freeze council tax.

Charities claim to have seen delays and decreases in funding from the NHS and local authorities partly as a result of the concordat, which means that traditional "ring-fencing" of money for certain areas has been scrapped.

The Herald reported earlier this year the concerns of the Prince's Trust which said the new arrangements would jeopardise services.

The survey, compiled by Community Health Exchange (Chex) which represents some 300 organisations, indicates that those concerns are now coming to pass.

DeafBlind Scotland works with 700 people and estimates there are 5000 sufferers of dual sensory loss across the country.

"We are suffering because of the changes to the funding structure," said Drena O'Malley, acting chief executive of the charity.

"At best we are heading for a neutral budget next year. We are at a loss as to know what to do."

Helen Tyrrell, of Voluntary Health Scotland, which provides support for health-related charities and community groups, said: "NHS Boards and local authorities must commit identifiable funds to local voluntary and community sector groups. At present, the expenditure that we know about is derisory."

Elspeth Gracey of Chex, who compiled the study, said it was the most difficult time for funding in the past 15 years.

"One National charity spoke of losing 100 staff which would affect hundreds of families across Scotland," she said.

Of the 16 organisations with funding to continue beyond this month, 11 have money for less than the next 12 months. Of those surveyed some 36% have reduced services in the last year and 50% of the surviving organisations said they will have to reduce their services after this month.

The most commonly cited causes of funding loss are from the NHS, local authorities and delays in access to community planning funds.

Robin Harper, the Green MSP, has raised a number of questions in parliament. "The NHS gets huge benefits from the work done by voluntary health organisations, but we don't think they get enough recognition or enough financial support," he said.

A spokesman for the Convention of Scottish Local Authorities said the majority of the examples given by the Community Health Exchange appeared to relate to NHS funding issues, and that councillors had worked to assist projects supporting the vulnerable in their communities.

He said: "The end of ring-fencing does not justify the doomsday scenario that the likes of the SCVO seem so keen to portray."

A Scottish Government spokeswoman said: "It is not the role of central government to fund local community health initiatives. This should be addressed by local funders as they are best placed to determine needs and priorities."

Dr Margaret Douglas, Consultant in Public Health Medicine at NHS Lothian, said: "In 2006-07 NHS Lothian provided funding of over £8.9m to voluntary sector organisations.

"We are undertaking a review of funding of voluntary and community health initiatives in Edinburgh in conjunction with City of Edinburgh Council and voluntary organisations. The purpose is to help us take a more strategic and sustainable approach to funding these initiatives."