Even as cases continue to trend upward in central and western Maine, the tri-county area has thus far avoided triggering the state’s new masking recommendations that say that all people, regardless of vaccination status, wear a mask indoors.

State health officials Saturday reported 91 new cases of COVID-19 in Maine, including three in Androscoggin County, one in Franklin County and four in Oxford County.

The Maine Center for Disease Control and Prevention no longer updates case data on Sundays and Mondays.

There was one additional death, a man in his 50s from Waldo County.

As of Saturday, Oxford County saw an average of 0.52 new cases per 10,000 residents within the past seven days, a fourfold increase compared to where it stood four weeks prior, when it stood at 0.1 cases per 10,000 residents. The average Saturday was a 133% increase from July 24, a week earlier.

As of Saturday, there was an average of 0.29 cases per 10,000 residents of Androscoggin County and an average of 0.38 cases per 10,000 residents of Franklin County.

Unlike Androscoggin and Oxford counties, as well as the state, Franklin County’s numbers were lower than where they stood at the start of the month. And for the first time in several months, the rolling averages of new cases in the tri-county area were lower than statewide averages during the month of July, an indication that the region is not the leading cause for the surge of cases across the state.

Maine officials announced last week that it would follow the U.S. CDC’s latest guidance that all people, regardless of vaccination status, should wear masks indoors in areas with substantial or high transmission rates.

The U.S. CDC designates counties as having low, moderate, substantial or high levels of transmission according to two metrics: the number of cumulative cases per 100,000 residents and the percentage of positive tests within a seven-day period.

As of Saturday, Somerset County and Waldo County saw substantial and high levels of transmission, respectively. The rest of the state had moderate levels of transmission.

The latest masking recommendations have caused some confusion in Maine. A county’s transmission designation may change from day-to-day, while some vaccinated people have expressed their frustration that unvaccinated people are driving the number of new cases.

They are also recommendations and not mandates. All state-enforced mandates related to COVID-19 ended June 30 when the state’s civil state of emergency expired.

The U.S. CDC and the Maine CDC have pointed to the delta variant, the highly contagious strain of the COVID-19 virus, as one of the primary factors that drove the decision to reinstate masking recommendations for vaccinated people.

“Based on what we know today, the delta variant is more wily and more formidable,” Maine CDC Director Dr. Nirav Shah said at a media briefing last week.

The state’s report on genome surveillance testing published Monday said that 75 cases of the delta variant have been identified in Maine, an increase of 46 cases from the July 23 report.

The delta variant was present in about 61% of all samples collected in July, the report said.

Since testing began in April, two cases each have been identified in Androscoggin and Franklin counties and three in Oxford County.

York County had the highest number of cases out of Maine’s 16 counties, with 11 total. Seven of those cases were identified in July alone.

The delta variant is “roughly twice as contagious as other strains” of the virus, Shah said.

“On top of all this, in rare situations, even people who are fully vaccinated can transmit COVID-19 to other people,” he said.

Internal documents from the U.S. CDC obtained by The Washington Post last week said that vaccinated people infected with the delta variant may spread the virus as easily as unvaccinated people compared to other strains of the virus.

Still, these so-called breakthrough cases are exceedingly rare. According to the latest data, 99.9% out of nearly 810,000 individuals have not become infected with COVID-19 after being fully vaccinated. In other words, the 656 breakthrough cases recorded in Maine shows that the risk to fully vaccinated individuals is extremely low.

Though the delta variant appears to be more deadly than other strains, the vaccines provide high levels of protection against severe illness in breakthrough cases, Shah said.

“The bottom line is simple: vaccines are still protecting us against severe illness,” Shah said. “But we’re seeing an increase in the rate of breakthrough cases nationwide. And one of those breakthrough cases could affect somebody who hasn’t been vaccinated.”

Transmission is largely being driven by unvaccinated people, Shah said.

“In fact, the vaccines can help prevent the delta variant from spreading even further,” he said. “Most of the spread that’s happening around the country is among unvaccinated individuals and in areas of low vaccination rates.”

U.S. CDC Director Dr. Rochelle Walensky in July called the latest surge in cases the “pandemic of the unvaccinated.”

As of Monday morning, 69% of all eligible Mainers – those 12 years and older – have received their final COVID-19 vaccine shots. Androscoggin, Franklin and Oxford counties have trailed behind the state since the beginning of the vaccine rollout late last year.

Out of eligible residents of Androscoggin County, 62% are fully inoculated. Franklin and Oxford counties are both behind, with 58% and 59% vaccination rates, respectively.