They are entitled to SSP (if they are eligible) for the first 14 days of self-isolation – anything after that 14 day period needs a sick note/isolation note to cover it and enable them to claim SSP. They can obtain an isolation note here: https://111.nhs.uk/isolation-note/
Your Personal Assistant (PA) will only be eligible to received SSP if they earn over £118 per week. If your PA hours vary – work out an average of their pay over the last 12 weeks – if this is £118 or over, they are eligible for SSP. If it is less than £118 per week, they are not eligible for SSP and it would therefore be UNPAID or could discuss a period of Annual leave.
Any changes to payroll including SSP needs to be reported to your payroll provider asap.
You can keep up to date on Gov.uk Website – SSP – https://www.gov.uk/statutory-sick-pay
https://www.gov.uk/statutory-sick-pay/eligibility
If your PA is not entitled to SSP:
An Employers must fill in the SSP1 form when an employee is not entitled to Statutory Sick Pay (SSP) or when their SSP is ending. More information on the link below: