We’ve been given a lot of public health messages over the course of the pandemic, from Boris Johnson’s OG mantra, “Stay Home, Protect The NHS, Save Lives” to its much mocked replacement “Stay Alert”, and perhaps the simplest of them all, as introduced last summer – “Hands, Face, Space”.

That last one morphed into cries of “Hands, Face, Dance” on Sunday night as party-goers flocked back to nightclubs to see in so-called “Freedom Day”.

But despite the easing of almost all remaining Covid-19 restrictions on July 19, there are many people who want – or very much need – to remain cautious.

As Covid cases continue to rise and the government pushes a new message of personal responsibility, England’s deputy chief medical officer, Professor Jonathan Van-Tam, had the following advice on Monday.

“I’ll just go back to what I’ve said at this podium more than once,” said Professor Van Tam at the Downing Street press conference.

“The principles of how Covid and how other respiratory viruses spread follow the Japanese three Cs, which the Japanese government have used to advise their citizens from the outset of this pandemic.”

So, what are the Japanese Three Cs?

It’s the health message Japan’s government have been promoting since March 2020, which is to avoid three key overlapping conditions. As Professor Van Tam explained on Monday (and not for the first time), these are:

“C number one: closed settings, where the ventilation is relatively low.

“C number two: crowded settings, where there are a lot of people per square metre.

“C number three: close social contact, if that’s the purpose of why you’re there and particularly if it’s with strangers or people you don’t normally mix with.”

As Professor Van Tam made clear: “Those are the things as scientists we are concerned about, wherever they occur and under whatever circumstances.”

His reminder came amid questions around the Covid safety of nightclubs and the government’s announcement that from September, all people going clubbing or to large events will need to present a vaccine passport, proving they have either been double jabbed or have recently tested negative for Covid 19.

“I don’t think it’s particularly helpful to pick out a particular kind of building or a particular kind of business [that has risk],” Professor Van-Tam said on Monday. “I could create the Japanese three Cs by inviting a load of strangers to a garden shed and sitting around having a beer with the door shut. That would do it.”

So, the message to the public: continue to be cautious in your own interactions to reduce your personal risk of catching – or transmitting – Covid-19. Bearing the Japanese Cs in mind and avoiding situations where they overlap may help.

How Japan will be implementing their own public health guidance at the Tokyo Olympics – set to be attended by thousands of athletes – remains to be seen.