The Terence Higgins Trust have put a page about the coronavirus on their website. Their advice is keep calm and carry on:
Am I at greater risk if I’m HIV positive?
There’s currently no evidence that people living with HIV are any more likely to catch COVID-19 than anyone else and you should follow the advice being given to the general population.
If you are on treatment, with an undetectable viral load and a good CD4 count (e.g. over 400), then there should be no greater risk.
If you’re living with HIV and do not have an undetectable viral load or have a low CD4 count, it will be more important to avoid situations where you may get infected if the virus becomes more widespread.
You can read the full article here.