THREE more positive COVID-19 cases were reported in Kerang on Thursday and a Swan Hill resident has tested positive while in Melbourne.

Swan Hill District Health chief executive Peter Abraham said a person with a Swan Hill address had tested positive to COVID in Melbourne.

"It's our belief they're not in Swan Hill or have been during their infectious period," Mr Abraham said.

"It's not known yet if that person has returned to Swan Hill, but our belief is that they haven't."

Mr Abraham said the case would be fully investigated by the Loddon Public Health Unit and the Melbourne COVID-19 contact tracing team.

Investigations were continuing.

The three new Kerang infections were household contacts of the initial case identified on Tuesday, a health-care worker who visited Woolworths.

The Exchange Hotel Kerang has been listed as a tier 1 exposure site after the cases attended the venue from 10.40am to 1.35pm on Tuesday.

Contract tracing interviews were under way.

People who visited the Exchange Hotel should get tested immediately.

A walk-in vaccination clinic is running on Friday from 11am to 2.30pm at W.D. Thomas Activity Centre, Burgoyne Street, Kerang.