AUGUSTA – Dr. Nirav Shah, director of the Maine Center for Disease Control and Prevention, said Wednesday, Jan 19, testing municipal wastewater is a better way to detect COVID-19 at the community level than daily case counts.

Twenty wastewater systems across the state will soon be tested and results will be posted on the Maine CDC dashboard showing how much of the virus is in communities. Shah said COVID-19 levels in wastewater precede illness in communities by “a couple of days” and can be used to warn hospitals before a spike starts.

By comparison, case counts are a reflection of how many cases can be processed by the Maine CDC lab in a 24-hour period and not how many people caught COVID-19 in that time. 

In order for a positive result to become a case, Shah explained, someone has to review it and make sure it is not a duplicate, and then the data must be entered into a U.S. CDC website. “That process takes us, and every other state and large city, time,” he said.

In light of what he called “the tsunami of omicron cases,” this process of converting a positive result into a case “has been even harder,” he said. Over the last seven days, Shah said, his agency has received on average 3,172 positive PCR and antigen tests every day. As of Dec. 30 of last year, less than three weeks ago, Maine CDC was receiving a combined total of 957 positive results daily. In less than three weeks the number of positive results has more than tripled, he said, a function of the omicron variant.

The massive increase in positive results has led to a backlog of 46,000 positive lab results waiting to be reviewed. Shah noted that the people to whom those positive lab results belong have received notification, perhaps from their health care provider or the lab, that they tested positive and should be isolating.

The popularity of home tests also means the case count data is an undercount, he said, because people do not notify Maine CDC of positive test results. “That’s OK,” he said, and added it is important to stay home and isolate upon receiving a positive test result.

With omicron symptoms being milder than the delta variant, some people might not even test at all, but are still spreading the disease, he said. Even though omicron is considered a milder strain on an individual level, on a community level, he said, the sheer number of hospitalizations can easily overwhelm a health care system. “It (omicron) is still significant,” he said.

The seven day positivity rate rose to 21.2% from 19.76% last week, and the number of PCR tests administered rose to 877 per 100,000 people from 825 last week. Currently there are 411 people in the hospital with the disease, up from 382 two weeks ago. As of today there are 102 people in intensive care units, down from 117 two weeks ago; 53 people are on ventilators, down from 59 two weeks ago.

While hospitalizations are up, the severity of cases has decreased, he said. Recent research shows 80% of new cases are of the omicron variant, with some studies showing 85% to 90% of cases attributed to omicron.

Overall, 76.8% of Mainers are fully vaccinated, with 49.4% of the population also being boosted. Maine CDC reported 30 additional COVID-19 related deaths in the state, including 13 women and 17 men ranging from under 20 to over 80. Out of the 30 deaths, 17 were identified through researching vital records from Nov. 15, 2021 to Dec. 29, 2021.

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