Thread by @IHME_UW

📄📌PRESS RELEASE: Our new COVID-19 forecasts show the possibility of a spring spike in United States deaths if variants spread widely and people let down their guard.

Details in the thread ⤵️

Our #COVID19 forecasts, which you can find in the link below, now incorporate two new virus variants:

B.1.351 (first detected in South Africa)
B.1.1.7 (first detected in the UK)
covid19.healthdata.org/global

In a worst-case scenario, with widespread transmission of the B.1.351 variant and mobility returning to pre-pandemic levels in the vaccinated, the US is predicted to see approximately 654,000 total deaths by May 1.

These states include California and Florida. Keeping mobility low and maintaining social distancing could reduce that number by approximately 30,000 according to our model's latest estimates.

Our Director, Dr. Christopher J.L. Murray, said that getting vaccines out quickly is essential and that masks are still one of the best tools we have to keep transmission low and avoid the worst possible outcome.

"People will need to continue taking precautions even once they are vaccinated because of the potential for more contagious variants to spread," Dr. Chris Murray said.

"What we’re seeing is sobering and will require us to continue taking this pandemic very seriously."

All scenarios in the new forecasts include vaccine distribution and the presence of the B.1.1.7 COVID-19 variant where it is currently detected.

Without transmission of B.1.351 our COVID-19 forecast for the US drops to 595,000 deaths by May 1, an increase of about 26,000 from last week’s predictions.

This increase is driven by taking into account that some states are not re-imposing social distancing mandates even when daily death rates are high.

Instead of assuming that decision-makers will re-impose social distancing mandates when deaths reach a threshold of 8 per million, all scenarios now assume that if mandates are not imposed promptly at that point, they will not be imposed until deaths reach 15 per million.

“We have not been seeing governments taking action to apply cautionary measures as quickly as expected, and have incorporated that information into the modeling,” said Dr. Chris Murray.

Herd immunity is unlikely to be a factor in slowing #COVID19 transmission in the coming months, even with vaccination campaigns ramping up.

That's because higher levels of immunity are needed with a more contagious COVID-19 variant during the winter months, and vaccine hesitancy is an obstacle to achieving herd immunity.

As important is the fact that we do not know if the vaccines work to block infection even though they prevent severe disease – our COVID-19 model currently assumes that vaccines’ effectiveness in blocking infection is only 50% of their effectiveness in preventing severe disease.

In the United States, approximately 25% of people have indicated they would reject a vaccine.

Another 25% are unsure.

Our COVID-19 forecasts predict only 38% of people in the US will be immune by May 1.

In a worst-case scenario according to our model, there is the possibility of a third wave next winter.

“Governments and the public need to plan for the real prospect that COVID-19 must be managed on an ongoing basis,” Dr. Murray said.

“It’s critical to vaccinate as many people as possible and to prepare for long-term behavior change. It’s likely that wearing masks and taking other measures to prevent transmission, especially in the winter months, will become an ongoing part of our lives," said Dr. Murray.

A copy of this press release is available on our website, right here ⤵️ healthdata.org/news-release/n…