There may be a second wave of coronavirus coming next year, one of the world's top health officials has warned.
Dr Robert Redfield, director of the Centers for Disease Control and Prevention (CDC) in the US, says even if the world can get a handle on COVID-19 this year, the outbreak could crop up again in 2021.
The reason for this, Dr Redfield explained to Good Morning America on Wednesday (local time), is that most respiratory illnesses follow a seasonal pattern, which means they show up more aggressively in winter.
As the vast majority of people live in the Earth's Northern Hemisphere - about 90 percent, according to a graph by Big Think - this makes the Northern Hemisphere winter a particularly worrisome time for the world's health officials.
"I think we have to assume this is like other respiratory viruses, and there will be a seasonality to it," Dr Redfield told host George Stephanopoulos.
"The CDC is science-based [and] data-driven, so we don't know for certain until we see it - but it is critical that we plan that this virus is likely to follow a seasonality pattern similar to flu.
"We're going to have another battle with it, up-front and aggressively, next winter."
There is some debate about whether colder weather causes COVID-19 to become more prevalent, however. Recent research out of China suggests the SARS-CoV-2 virus actually spreads just as easily in hot, humid weather as it does in the cold.
While this might mean bad news for Northern Hemisphere, it means New Zealand's coming winter might not exacerbate the outbreak, should the lockdown fail.
Later in the interview, Dr Redfield also admitted that the COVID-19 outbreak had "got ahead" of the US, and that they were under-prepared when it hit.
The US now has more than 643,000 cases of COVID-19, and more than 28,000 people have died with the disease there. That's despite President Donald Trump vowing in February that he would get the number of cases, which was 15 at the time, down to zero within a week.
On Tuesday (local time), President Trump withdrew his country's funding of the World Health Organization, accusing it of covering up the true threat of COVID-19.
