COVID measures in Wales are to be strengthened in an attempt to reduce high levels of the virus.
Infection rates in Wales are currently higher than any other part of the UK.
First Minister Mark Drakeford said COVID-19 cases have "risen sharply to the highest rates we have seen since the pandemic began and more people are falling so seriously ill that they need hospital treatment".
He continued: "All this means that the pandemic is far from over.
"We need to take more action now to strengthen the measures we have in place at alert level zero to prevent coronavirus spreading even further and more people falling seriously ill."
Mr Drakeford expressed his hope that the action would "help to turn the tide".
But he said further restrictions on top of these measures may be needed in order to bring the spread of COVID under control.
"None of us wants to see a return to restrictions but if rates continue to rise, the cabinet will have no choice but to consider raising the alert level at the next review," the first minister said.
Wales is to remain at alert level zero, but extra measures will be introduced to tackle high coronavirus case rates.
Isolation guidance will change - fully-vaccinated adults and children aged five to 17 will be asked to isolate themselves until they get a negative PCR test if someone in their household has symptoms of the virus or tests positive.
Those who are not vaccinated will still have to isolate for 10 days if they come into contact with someone who has tested positive, including close contacts not in their household.
The Welsh government also said it "intends" to extend the use of the COVID Pass to theatres, cinemas and concert halls from 15 November.
This requires people to provide proof of their vaccination status or evidence of a recent negative lateral flow test.
Meanwhile, headteachers will get more support to quickly introduce measures in schools if local rates are high.
Staff and secondary school students will be encouraged to test themselves twice a week using lateral flow tests, the government said.
It said that vaccines "remain the best defence against the virus", adding that talks have been held with the Joint Committee on Vaccination and Immunisation on the best interval between the second dose and a booster jab.
People are being encouraged to keep working from home "wherever possible" and wear a face covering in indoor public places.
Economy minister Vaughan Gething met retailers on Wednesday and encouraged them to do everything they could to raise awareness of this legal requirement.