Albury now has the second-highest number of active cases out of all NSW local government areas, and Wodonga's tally is the fastest-growing in Victoria.
However, health officials are confident additional resources from each state and high vaccination rates will keep our outbreak contained.
Thirty-four new cases yesterday brought Albury's active case count to 296; second only to Canterbury-Bankstown in Sydney with 345 cases.
Wodonga recorded 46 cases, which has made the city home to the fastest-growing outbreak in Victoria.
The state's COVID Commander Jeroen Weimar described the outbreak as "well contained".
"We're seeing again a large number of unvaccainated people who are catching COVID and spreading it in their networks and that's why our action plan up there is around trying to minimise that," he said.
An infectious disease modeller at Monash University felt it was too early to quantify the effective reproduction number for the outbreak, but noted transmission may have gone undetected.
As more exposure sites are added and day-13 testing approaches, a multi-lane drive-through testing clinic is being planned for Albury-Wodonga.
Extending hours of Albury Wodonga Health's three testing clinics is also being considered.
AWH public health executive director Lucie Shanahan said while clinics did not reach capacity early today, she expected sites "would remain at capacity for some time".
"One of the key reasons ... is because of the population group that we're seeing this outbreak occur in, which is primarily school aged children, given that young people aged 12 years and above have had access to the vaccine for the shortest amount of time," she said.
"We know that there are a large number of school students who have not yet been fully vaccinated, so we're really pushing for particularly high school aged kids who are eligible for vaccine to come forward and get vaccinated.
"We are seeing the majority of the cases continue to appear in the five to 30 year age group.
"We're working with both Albury and Wodonga councils to look at alternative testing sites and to look at where we may be able to establish a multi-lane drive through on the Victorian side of the border."
Close to 900 tests were done through three AWH sites yesterday and well over 1000 were completed at Albury sites, as new high-traffic venues were made tier one exposure sites.
"If you have been at the sites during the times and the date specified, we ask you to come forward for testing," Ms Shanahan said.
"We also ask you to come forward for testing if you're symptomatic or if you've been contacted by the Department of Health or your school and asked to come forward for testing.
"If you don't fall into those categories, we ask you to please not come forward for testing at this time.
"We're always thankful for people that come forward for testing, but at the moment with rolling exposures through our school communities, we're seeing a lot of people come forward for testing because they are anxious and nervous.
"We completely understand that, but our three priority groups ... are who we ask to come forward for testing at this time."
When asked about the discrepancy in support given to Albury-Wodonga compared to Shepparton in their recent outbreak, Ms Shanahan said testing teams from Melbourne had already been deployed.
"We've had really fantastic support from the Department of Health in understanding the current outbreak in Albury-Wodonga and the resourcing and support that's required," she said.
"We do have a really good sense now of the main population groups that have been impacted by this by this particular outbreak.
"We had a Deputy Chief Health Officer on site with us across the course of the weekend ... and we have had direct contact with Jeroen Weimar.
"One of the key differences between what we're experiencing here in Albury-Wodonga as an outbreak and what other regional centres across Victoria have seen is that we're sitting at an 80 per cent vaccination rate, and that is a huge thing that is in our favour."
Ms Shanahan did not dispute Mr Weimar's characterisation of the outbreak as "contained", saying the increasing new case tallies did not come as a surprise.
"It doesn't mean to say that we're not concerned; we are concerned about the spread of the virus and about the the frequent increase in numbers that we're seeing," she said.
"It's why we're asking people to help us out and take some really, really simple steps that is to get vaccinated, to wear a mask and to minimise social gatherings.
"We know it's really hard - we've got beautiful weather in the North East at the moment and the state is opening up, but we are asking people just to think about the size of the social gathering that you're attending.
"It is possible over the next little while, certainly as the regions open up ... that we may well see more tier one exposure sites."
Albury Wodonga Health has provided Beechworth Health Service with support, who were praised for acting quickly and "absolutely have the situation in hand", and a forum was held with St Monica's last night to address concerns.
"It was a great opportunity to talk directly with parents about what we're seeing in this current outbreak, which is primarily occurring in school aged children and young people," Ms Shanahan said.
"Anyone aged 12 and above can come forward for a vaccine; we are continuing to run our after-hours session on a Thursday evening and the hub will also be open on Saturdays as well which will make things a little bit easier for families to be able to access the vaccine.
"One of the other key messages for the community at the moment is, generally in children and young people, we don't see significant illness or severe illness.
IN OTHER NEWS:
"None of the people who are currently admitted to Albury Hospital are children or adolescents.
"We know that children and young people do become unwell, but often ... what they're experiencing is not is not as significant or or requires hospitalization."
There are seven people in hospital but none are requiring intensive care.