Despite the current media and political glare, coronavirus is a silent killer. Since one neither sees the virus nor knows who may be spreading it unaware, perhaps even oneself, life appears normal on the surface. For many, it is hard to accept the preventive measures that would be draconian in normal times, and easy to believe that government, the media and businesses are overreacting when, in fact, these measures are typically too little, too late.

The key preventive concepts are to “flatten the curve,” through “social distancing,” that is, strategies to try to spread out the rate of infection over a longer period. This reduces the peak burden on overstretched medical institutions, saves lives, and buys time to produce vital medical equipment and develop vaccines.

Flattening the curve is also critical for the economy, particularly an economy like ours that is so dependent on tourism. Since normal life is disrupted through strict social distancing at the beginning, business often initially opposes what seem extreme measures, but in the longer term, they reduce economic costs and improve the prospects of an earlier recovery.

With any epidemic, the goal is to bring down the rate of spread of the pathogen, and eventually to fully suppress it. It begins to end when the average sick person infects less than one other person. Speed is essential. With infections in the U.S. increasing in the past few days at an exponential rate, we are at an inflection point. British epidemiologist Britta Jewell notes that just one infection prevented during such a period will prevent 2,400 further infections a month from now, as compared to only 600 if the measures were delayed a week.

Unfortunately, some people spread it more easily than others. An Italian hospital failed to recognize that one 38-year-old, a super spreader, had COVID-19. Because he was not isolated, he infected many others, sparking the rapid onset of the disease in Italy.

Eliminating unnecessary gatherings and reducing the size of others is key. If a super spreader is at a meeting of 50 people in Waikiki, at church, or at an exercise group, he or she may touch off a community spread that is exponentially wider than if the group was only 10. Those who rush to a crowded store to hoard toilet paper or to their favorite restaurant to meet friends are also not just endangering themselves, but others.

Seniors have special risks and responsibilities because they are more vulnerable to severe infections that could overburden the medical system. But all must do their part. Half those in hospitals with coronavirus are under 65. Although relatively mild for some, this disease is no severe cold or flu. The mortality rate appears to be at least six and maybe 40 times higher; there are no treatments; and 1 in every 20 requires hospitalization, many needing oxygen requiring scarce ventilators.

While longer-term impacts are still unknown, COVID-19 seems to attack internal organs more seriously and leave life-long lung scarring.

Hawaii’s geography and distance from supplies pose a particular set of challenges. Hoarding is a problem in any crisis because what seems rational from the individual perspective (get supplies before they run out) is irrational from a community point of view, where short supplies of face masks and sanitizers are critically needed for medical personnel, those who have the disease, and public buildings and institutions. This is why in wartime, rationing is essential from the outset.

The U.S. lost precious time when COVID-19 was widely perceived to be a foreign disease even as it was spreading silently within. As it continues to spread exponentially, drastic measures of the kind now being imposed in Hawaii are not an overreaction but an absolute necessity to contain and defeat the disease.

Charles E. Morrison is an adjunct fellow and former president of the East-West Center.