An 85-year-old woman from Carmarthenshire with Alzheimer’s disease who was plagued by nuisance callers and sometimes left in tears isn’t any more after a call screening device was installed on her phone.

The woman is one of many in the county who has had the call-blocking device fitted, and Carmarthenshire County Council chiefs said the initiative has stopped hundreds of thousands of nuisance calls and prevented vulnerable people parting with a lot of money since it was introduced in 2014.

A report before a council scrutiny committee said the 85-year-old’s niece arrived at her home one day last year to find her “desperately looking” for her bank card while on the phone to a scam caller.

The niece told the council’s Trading Standards department that her aunt was receiving dozens of nuisance calls a day and that she’d find her distressed and in tears unable to understand why she was receiving so many.

Trading Standards installed the device, called trueCall, and programmed it to “trusted caller only” after some callers had managed to bypass an initial “filter only” setting.

According to the report the niece said her aunt was now only receiving calls from people on the truster caller list and that it was working brilliantly.

The report said trueCall devices in Carmarthenshire had blocked 230,029 nuisance calls including 49,762 known scam numbers since being introduced in 2014 and resulted in estimated savings of more than £1.3m for residents and over £805,000 for the police, NHS and social care.

Speaking at a place, sustainability and climate change scrutiny committee meeting, councillor and cabinet member Aled Vaughan Owen said: “Behind these numbers are real people – families who are dealing with distress, confusion and relentless harassment.”

Trading Standards meanwhile has developed monitoring technology of its own to complement the devices, generating 155 alerts since 2022, investigations of suspicious numbers and visits in person to people’s homes. This monitoring technology is being used in three other local authority areas in the UK.

The report said the benefit overall for residents was reduced exposure to “aggressive and distressing” calls, leading to measurable improvements in well-being and peace of mind. The service, it said, hasn’t been rolled out to all elderly and vulnerable residents but demand remained strong.

A council officer said trueCall was working on a mobile phone version of the call-blocking device.

Committee chairman, Cllr Kevin Madge, said he welcomed the report and said many people were bothered by calls of the type being discussed. “Let’s be honest, the nuisance calls, we all experience them now,” he said.