Tri-county COVID update shows growth rate ‘way down’ – but will three-month pattern show up here?

September 24, 2020
Graph showing decrease in COVID cases
This graph from the MUSC COVID-19 Epidemiology Intelligence Project shows the number of confirmed COVID-19 cases in Charleston County.

The leader of the MUSC COVID-19 Epidemiology Intelligence Project is pleased to see that the coronavirus growth rate shrank to 0.2% in the latest situation assessment for the Tri-county area. 

“We’re way down,” said Michael Sweat, Ph.D. “I think we’re at the lowest growth rate we’ve had to date. It’s been very consistently low this week.” That keeps it in the green on his team’s green, yellow, red scale.

The situation assessment also shows a sustained reduction in new cases for Berkeley, Charleston and Dorchester counties over a 14-day period, another key metric that has gone green.

And while the number of reported COVID-19 infections per 10,000 people per week in the Tri-county area is still in the red category, it may not stay there for long. It plunged from more than 1,000 the first week of September to 396 in the latest assessment. If it gets below 388 cases in the coming week, that indicator will turn yellow. 

“That’s really good. But I don’t think the message ought to be, ‘Things are so good, now we can relax.’ We need to stick with it,” Sweat said.

Here’s why.

“There’s a three-month pattern. It’s so striking when you look at what’s going on in Europe.”

Graph showing increase in COVID cases in Europe .

Sweat charted the virus’ trajectory in Spain, France, the United Kingdom, Italy and Germany. “This was Spain when they had their massive outbreak before we had ours,” he said, pointing to a light blue line showing a peak in mid-March.

“They drove their rates to almost zero at the beginning of summer. Then they said, ‘We’ve done so great, we’re going to move into containment and relaxation mode.’ They opened restaurants, allowed people to travel. They went out and started visiting family. And now, Spain, within a matter of weeks, is worse off than they were at the peak of their terrible epidemic.”

The number of COVID cases in France is now higher than its previous peak, too. And Sweat said the U.K. is on track to follow suit. “They’re all instituting major lockdowns.” 

The number of cases in Italy and Germany is up, too, although not as dramatically.

“I think it’s a combination of fatigue and people being smart enough to see things aren’t so risky because the numbers are low. They go back to their old ways – a little bit, even – and the numbers go back up again. You see it in country after country, this three-month undulation.”

So if the Tri-county area follows that three-month pattern, it could be in for a COVID bump this fall. “It puts you into some time in October, potentially seeing another rise here,” Sweat said.

“I think the consensus among really good epidemiologists and public health experts is you can’t relax and assume the worst is behind you. You really have to keep the vigilance up. That being said, we are learning a lot about how to make things work and not work. Society is functioning pretty well with the current situation,” Sweat said. 

“If we could just get everybody to keep doing what we’re doing, we could keep this at a very low level. And not have many hospitalizations, et cetera. But there are signals coming out from other places that we should be worried about.”

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