Coronavirus pandemic won't be controlled until two-thirds of the population has immunity: experts

Government leaders and public health officials need to prepare the public to deal with COVID-19 for the long haul, according to a new report that says the pandemic will likely last two years, Bloomberg reported.

"Risk communication messaging from government officials should incorporate the concept that this pandemic will not be over soon, and that people need to be prepared for possible periodic resurgences of disease over the next two years," the report from the University of Minnesota said.

What's the story? According to a report by experts at the Center for Infectious Disease Research and Policy at the University of Minnesota, the pandemic caused by the novel coronavirus that originated in Wuhan, China, will not be under control until 60%-70% of the population is immune to it.

"Whichever scenario the pandemic follows (assuming at least some level of ongoing mitigation measures), we must be prepared for at least another 18 to 24 months of significant COVID-19 activity, with hot spots popping up periodically in diverse geographic areas," the report says.

Three scenarios: The researchers anticipate the virus to progress one of three ways over the next two years:

• First wave in spring 2020; repetitive smaller waves through the summer that continue over a two-year period (may require some social distancing/isolation policies in some areas)
• First wave in spring 2020; larger wave in fall/winter 2020; smaller wave(s) in 2021 (would require reinstitution of mitigation policies in the fall)
• First wave spring 2020 followed by continuous slow burn without a distinctive wave pattern (would not require mitigation policies)

There is still uncertainty about COVID-19, including the level and duration of immunity people have after recovering from the virus, and when (or whether) an effective vaccine will be developed. From the report:

This may be complicated by the fact that we don't yet know the duration of immunity to natural SARS-CoV-2 infection (it could be as short as a few months or as long as several years). Based on seasonal coronaviruses, we can anticipate that even if immunity declines after exposure, there may still be some protection against disease severity and reduced contagiousness, but this remains to be assessed for SARS-CoV-2. The course of the pandemic also could be influenced by a vaccine; however, a vaccine will likely not be available until at least sometime in 2021. And we don't know what kinds of challenges could arise during vaccine development that could delay the timeline.