People must be acutely aware that their everyday actions have an impact on the course of the pandemic, World Health Organisation chief Tedros Adhanom Ghebreyesus says as the global case count climbs above 15 million.
"We are asking everyone to treat the decisions about where they go, what they do and who they meet with as life-and-death decisions - because they are," the UN health chief told a press conference in Geneva on Thursday.
"It may not be your life but your choices could be the difference between life and death for someone you love or for a complete stranger," he added.
Tedros said people in countries that have already brought infections rates down should be especially vigilant about keeping up to date on the latest infection trend where they live, about keeping physical distance, about hand hygiene and about following public health advice.
Tedros also said the WHO was recording intense transmission of the coronavirus in relatively few countries.
"Two-thirds of all cases are from 10 countries. Almost half of all cases reported so far are from just three countries," he said, referring to the United States, Brazil and India.
US coronavirus cases exceeded 4 million on Thursday, with more than 2600 new cases every hour on average - the highest rate in the world, according to a Reuters tally.
Tedros also said that just because cases may be at a low level where someone lives, it doesn't mean they should let down their guard.
"Know your situation - do you know how many cases were reported where you live yesterday? Do you know how to find that information? Do you know how to minimise your exposure?"
The small, neighbouring sheikhdoms of Bahrain and Qatar appear to have among world's highest per capita rates of confirmed coronavirus infections, according to studies,
This is thought to be because of extensive testing and the rapid undetected spread through camps housing healthy and young foreign labourers.
In Qatar, a new study concluded that nearly 60 per cent of those that tested positive showed few or no symptoms at all.
Qatar had 37.4 coronavirus cases per 100,000 people, the highest rate of confirmed cases in the world, according to figures from the University of Oxford.
Bahrain, at 22.1 confirmed cases per 100,000, is second.
Other countries with high confirmed rates per population include San Marino, Chile, the Vatican, Kuwait, Oman, Panama and Armenia while the US is tenth on the list.