In other words, a lockdown is mostly a delaying tactic. By distributing cases over time, it can help manage an outbreak — but only if it takes place against the backdrop of a robust health care system. Yet even the best system is too fragile, and a moderate increase in infectious cases, whether of seasonal flu or Covid-19, can quickly overwhelm resources, in China or the United States.

As chilling as it is to imagine this scenario, what happened in Wuhan, the Chinese city at the epicenter of the outbreak, will likely play out elsewhere, too. Hospitals might have to turn away all but the people most seriously ill; their ability to handle their usual load of patients with heart attacks, critical injuries or cancers may be severely compromised.

In a world ill-prepared for a potentially life-threatening, easily transmitted disease like Covid-19, the most effective way to mitigate the pandemic’s impact is to focus on supporting health care systems that already are overburdened.

This is the main reason every country’s top priority should be to protect its health care workers.

The United States and other countries in the Northern Hemisphere already are in the throes of a moderately serious flu season. Their inventories of protective equipment used by doctors, nurses and emergency medical workers — N-95 respirator masks, gloves, eye protection, disposable suits — are running low. These limited supplies must go to health care workers first, rather than the public. This is partly to ensure that hospitals themselves do not become sites where the coronavirus is spread more than it is contained: If infected health care workers die in large numbers, entire societies may be shaken to the point of panic.

Governments should also conduct Covid-19 preparedness drills in local hospitals and expand hospitals’ temporary capacity, for example, by setting up emergency tents in parking lots, as is already happening in some places in the United States. To minimize the strain on overstressed acute-care hospitals, supportive nursing care might have to be provided, in makeshift facilities and patients’ homes, as was done during severe pandemics in the past, such as the Great Influenza of 1918-19.

The manufacturing and distribution chains for drugs and other vital products like needles and syringes must remain open, and that, given the global nature of the industry, requires international cooperation. In keeping with World Health Organization guidelines, coronavirus-stricken countries shouldn’t be walled off the way that the United States and others are trying to do with China at the moment. Otherwise, as the virus spreads, we will be isolating ourselves, too, and will jeopardize our ability to obtain critical resources. Many of the active ingredients in lifesaving generic drugs — the ones that stock hospital crash carts and maintain our daily well-being — come from China and India. If that production is brought to a standstill, many people could die, not directly from Covid-19, but indirectly from a lack of access to those drugs.

Ensuring all of this means facing the hard facts of this unfolding pandemic — and that requires thorough, transparent disclosures to the public. Past experiences, with the anthrax-laced letters in 2001 and the 2014 Ebola outbreak, suggest that people react more rationally and show greater resilience to a full-blown crisis if they are prepared intellectually and emotionally for it.