British Columbia鈥檚 top doctor says the surge in COVID-19 cases is fuelled by those between the ages of 20 and 40 who are unvaccinated or have only had one dose.

The latest daily case count reached 342 on Wednesday, a figure not seen since late May, but Dr. Bonnie Henry says clusters of infections were expected.

Henry says the key is that health officials aren鈥檛 seeing widespread transmission to at-risk groups such as seniors because they have a high rate of immunization.

She says pandemic modelling shows the Delta variant is more transmissible, which means immunization rates must go up, and even a small increase in vaccinations makes a difference.

Health Minister Adrian Dix says people aren鈥檛 obliged to get vaccinated, but warns that the unimmunized might face consequences at work and certainly if they hope to travel outside of the country.

The government鈥檚 promotion of 鈥淲alk-in Wednesday鈥� saw more than 16,500 people go to clinics across the province without an appointment to get vaccinated, with more than 6,000 going for their first shot.

鈥擳he Canadian Press