"There's never been a better time for America to get healthy."

That's one of the messages from Dr. David Katz, founding director of Yale University's Yale-Griffin Prevention Research Center, in a 15-minute interview with Bill Maher on HBO.

Katz, a past president of the American College of Lifestyle Medicine, pointed out that it's hard to convince many people to stop drinking and smoking and to eat well because it takes too long for the benefits to become apparent.

"Essentially, heart disease stalks you in slow motion," Katz told Maher. "Type 2 diabetes stalks you in slow motion. Our DNA is wired to fight or flight."

However, according to Katz, the COVID-19 pandemic has turned chronic health liabilities like heart disease and type 2 diabetes into acute threats.

That's because these conditions sharply elevate the risk for those who contract the novel coronavirus.

Katz thinks there should be a national health-promotion campaign to encourage people to improve their diets and lifestyle before they become infected.

https://twitter.com/DrDavidKatz/status/1254398192587849729

He recently volunteered as an emergency doctor in the Bronx, helping other health-care providers in the fight against COVID-19.

This experience, along with his expertise in epidemiology and lifestyle medicine, had led him to conclude that COVID-19 affects different populations differently, based on their age and prior health.

"Currently there is no guidance for what comes after 'flattening the curve'," Katz states on his website. "While flattening the curve as best we can is essential in this initial phase, models show that without a longer-term, risk-based plan, it delays—but does not prevent—a spike in hospital need and mortality, unless maintained until a vaccine is available."

Phase two carries its own set of risks

In his interview with Maher, Katz noted that world-class risk modellers have demonstrated that simply lifting a lockdown won't cultivate immunity to COVID-19.

"The minute you release those clamps and let people back into the world, we're all vulnerable," Katz explained.

He readily acknowledged that most of the models suggest that flattening the curve makes sense in phase one so that medical systems aren't overwhelmed.

"But you've got to have a phase two," he added. "If you don't transition to a phase two, whenever you release the clamps, the virus is out in the world waiting for you.

"Everybody is vulnerable," he continued. "And that big peak in cases and that big peak in deaths that you were trying to avoid really just happens at a later date."

At the same time, Katz doesn't support the approach in Sweden, where bars, restaurants, and hair salons remain open.

He also noted that the media tends to amplify extremes.

In his view, these range from the "hunker into a bunker approach" until there's a vaccine to "throwing everyone in the water, including grandma, and never mind the rip tides and the sharks".

Katz advocates a different path—identifying those who are at risk of a severe infection and those who are not.

"Sweden's approach is a little too close to the 'everybody in the water, don't worry about the rip tide' end of the spectrum for my taste," Katz said. "I think we can do even better."

He prefers "harm minimization".

"The middle path is [that] high risk people are protected from exposure," Katz told Maher. "Low-risk people go out into the world early."

The alternative, Katz said, is wait for a vaccine, which might be ready in 18 months but could take longer.

In the meantime, he said that millions of people's livelihoods will have been destroyed, elevating their risk of dying from other factors.

That's because poverty is strongly linked to early mortality and a range of other health problems.

This is apart from the sharp rise in domestic violence being reported by women's organizations, including Battered Women's Support Services in Vancouver.

Death toll high, but ratio to infections is low

According to Katz, COVID-19's death rate in New York is probably lower than 0.5 percent.

He drew this conclusion based this on widespread testing, which shows that at least 20 percent of New York's population may have antibodies.

If true, it means four million have contracted the virus in New York, where there have been 16,966 fatalities as of April 26.

The fatality rate from COVID-19 is derived by dividing the number of deaths (numerator) between the number of cases (denominator).

"I think the denominator is even larger than that," Katz said.

In effect, he suggested that 98 to 99 percent of infections in New York have been "mild", whereas a small portion of the cases are potentially severe, mostly the old and sick.

But he also cautioned that a lot of young people suffer from coronary disease, obesity, diabetes, and hypertension, so distinctions can't simply be made on the basis of age.

Today, New York's governor. Andrew Cuomo, reported that there were 367 COVID-19 deaths over the past 24 hours, the lowest figure in nearly a month. There were 5,902 new cases, bringing the total to 288,045 in New York.

Cuomo said that because the caseload is dropping, it may be possible to gradually begin restarting the economy by May 15, starting with manufacturing and construction in upstate New York.