Their website says "You must go to jury service unless the court agrees to put off (defer) your jury service or excuses you. If you don’t attend, you can be fined up to $1000." I would say go down and cough on them for the stupidity of their policies, but you'd get arrested, so don't do that. Instead you're probably best to stay home and call in the morning, tell them you're going to get a covid test. No-one will want you anywhere near them.

Their website says "To find out more about putting off your jury service to a later date or being excused from jury service, read your jury summons response form and the information that comes with it.". Does the summons or the information that comes with it say anything about this? It has to be quite common that people get sick and can't make it.

Update two: The Justice website says "If you're unwell, please don't attend court. Please call 0800 COURTS (0800 268 787) for further instruction."

Cool thank you I will call tomorrow before going and get instruction from them.