High Death Rate in Hong Kong Shows Importance of Vaccinating the Elderly

The first time the Omicron variant breached Hong Kong’s coronavirus defenses, in late 2021, the city stamped it out, cementing its status as one of the world’s most formidable redoubts of “zero Covid.”

But a few weeks later, Omicron came to the metropolis again, this time causing an outbreak among cleaners at a public-housing estate that spiraled out of control. The conflagration of resulting cases is now killing people at a rate exceeding that of almost any country since the coronavirus emerged.

Over the entire pandemic, Hong Kong’s death toll per capita, once far lower than those of Western nations, is no longer exceptional. A month ago, Americans had died from Covid at 90 times the rate of people in Hong Kong. By Monday, the cumulative American toll was three and a half times as high.

As the United States braces for its own, less punishing rise in cases, and mainland China battles its biggest outbreak in two years, scientists have looked to Hong Kong for clues about the threat Omicron poses in an entirely different setting: a dense city where people were not only largely untouched by previous infections, but whose oldest and most vulnerable residents were also largely unvaccinated.

Several critical lessons emerged, health experts said.

In the era of Omicron and its even more infectious subvariant, BA.2, vaccinating a broad swath of the population remained important, scientists said. But inoculating as many older people as possible had become far and away the top priority.

That message, they said, was most pressing for China, where vaccinations in older age groups also appear to be lagging and there is little immunity from earlier infections.

But it was relevant again in the United States, too, where subpar vaccination and booster rates among older people have left scientists concerned about a potential surge of BA.2 cases. Partly because so many more Americans have been infected and killed by the coronavirus during earlier waves, scientists do not expect the United States to face as serious a situation in the coming months as Hong Kong.

Hong Kong’s dreadful outbreak also signals the perils of trying to eliminate the virus without a plan for what would come next, health experts said. Omicron’s high transmissibility, they said, made outbreaks almost inevitable. ...