VICTORIAN Premier Daniel Andrews must protect regional communities from the threat of COVID-19 by closing holes in his "mythical ring" around Melbourne and the Mitchell shire.

That is the message from Member for Northern Victoria Wendy Lovell, who said workers from Melbourne and a lack of screening of passengers on public transport pose a risk to regional communities while the virus spreads in the metro area.

Regions like Mildura have not had a new active case for months, and the biggest threat remains people from Melbourne visiting.

"It is understandable that some exceptions need to be made to allow for the delivery of essential supplies and for those who provide critical services," Ms Lovell said.

"However the government must do more to ensure those moving between the lockdown and non-lockdown areas are doing so for essential reasons, that they are screened for risk and that their movements are limited to avoid unnecessary contact with the local community.

"Regional V/Line services also pose a risk to the regions with many passengers reporting they were not screened in anyway or asked for proof of residency or reason for travelling to regional areas."