3 theories why Covid-19 shows signs of 'decelerating' in Wisconsin from MCW's Dr. John Raymond
The evidence is mounting emerging that the Covid-19 pandemic in Wisconsin is decelerating — including avoiding a post-Thanksgiving surge — and Medical College of Wisconsin president and CEO Dr. John Raymond Sr. says there are three possible reasons.
Raymond noted in remarks on webinars Monday and Tuesday that Covid-19 hospitalizations, which is the most objective measure of the disease’s severity, have continued a downward trend the past four weeks. Also, the number of new cases diagnosed has plummeted and the number of deaths is beginning to decline, he said.
Public health experts in Wisconsin and elsewhere had warned that with more people visiting friends and relatives over the Thanksgiving weekend, there was a high risk of a spike in cases. In response to a question Tuesday from Metropolitan Milwaukee Association of Commerce president Tim Sheehy, Raymond said: “We haven’t seen a surge” in cases since Thanksgiving.
The most plausible cause for Wisconsin’s improving Covid-19 statistics is that Wisconsinites are practicing safety measures, including wearing masks and social distancing, Raymond told the MMAC audience Tuesday and the Greater Milwaukee Committee on Monday.
He believes more people became concerned about hospitals and intensive care units filling up and changed their behaviors.
“First and foremost is that people are being more diligent about protecting themselves — especially when they saw their ICUs were 95 percent full five weeks ago,” Raymond said during the MMAC webinar. “This is most likely a contributing factor.”
The other two hypotheses are more speculative, Raymond said.
The first is “the low hanging fruit hypothesis," he said.
This theory holds that the people who are most susceptible to the novel coronavirus already have been infected. These individuals include those who engage in less-cautious behaviors or are in higher-risk groups, including older people, Raymond said.
The second theory relates to social networks. The idea is that “key people who sit at connecting points” of their social networks already have been infected and now are in the hospital or quarantining, thus slowing the spread, Raymond said.
“We still know that the large majority of cases that are occurring in the community are in small gatherings within people’s households,” he said. “That doesn’t mean there aren’t transmissions in nursing homes and places of work.”
There are two possible factors that definitely are not causing the deceleration, Raymond said.
The first is herd immunity, which is the prediction that if 70% to 75% of the population becomes immune, the spread will stop. Raymond said the highest immunity estimates he has seen for Wisconsin are “hovering around 30%.”
The second is the decrease in the number of people getting tested. Raymond said while fewer people are getting tested, that is not a factor because the number of hospitalizations and deaths remain at very high levels and above previous peaks in spring and summer.
Wisconsin is running three to four weeks ahead of the rest of the United States in terms of its improving pandemic conditions, Raymond said.
Despite the fact that the pandemic is decelerating, people need to practice the Covid-19 safety guidelines over the holiday season to avoid an uptick in cases and hospitalizations, Raymond said. Hospitalizations in Wisconsin have dropped steadily from their peak of 2,277 on Nov. 18 to 1,471 on Monday, Raymond said. ICU censuses also have declined to more manageable levels from their peak on Nov. 16, he said. While those figures are much improved from a month ago, they remain much higher than where they were during the low points this summer when hospitalizations fell to 235, Raymond said. The seven-day Covid-19 death rate in Wisconsin has started to drop but remains high at an average of 47 the past seven days, Raymond said. He anticipates the death rate will remain high the remainder of 2020 and possibly into January 2021. “It appears that deaths are plateauing and may be continuing to trend downward,” he said.