Even among those who had developed a habit of guarding against COVID-19 during the pandemic, most have dropped vigilance — just at the moment when new highly infectious variants, KP.2 and KP.3, are circulating.

The result, of course, is that more people are getting infected. Bad memories flood back: COVID-19 illness can be miserable for those who are younger and otherwise healthy, and even more perilous for the seniors and those with an underlying condition. Many of those in the more-vulnerable class may be unaware that an additional vaccine dose is recommended for them.

Worrisome increases are happening in Hawaii and across the nation. Tracking underway by the state Department of Health shows the activity level trending in recent weeks from green to yellow, and now to red. This indicates that “the virus is circulating at high levels compared with historic trends,” according to the department.

The red alert is on display publicly on the new DOH respiratory-disease dashboard (health.hawaii.gov/docd/disease-types/respiratory-viruses).

With an increase in summer travel anticipated, the chance of exposure is only going to rise further.

Clearly, the impulse to push COVID-19 into the past isn’t justifiable, as much as everyone wishes they could do just that. The increase in mask-wearing that many are noticing in public places is evidence that some people have gotten sick, or at least gotten the message about risk.

The imperative is to heighten that level of vigilance, through a return to some of the common-sense safeguards everyone knows all too well. These include: keeping up to date on vaccines, masking when in an enclosed space for an extended period, adhering to good hand-washing habits, staying home when symptoms of illness arise, and getting a test before exposing others.

So far, hospitalizations here are higher than they’ve been this year but have not surged to a worrisome level, although that metric bears careful watching. Hawaii can’t afford to overburden its health-care system, as nearly happened during the worst of the pandemic.

The KP strains are part of a family known as the “FLiRT variants,” named after the technical term for their mutations. According to the Centers for Disease Control and Prevention (CDC), KP.2 caused about 4% of infections nationally but overtook JN.1 as the dominant strain in early May. Now it makes up about 28% of infections, according to the Johns Hopkins Bloomberg School of Public Health, spreading at an alarming pace.

It doesn’t make it any easier that control of this disease is such a moving target. Last fall, many people received their last dose of updated vaccine and believed public-health policy had shifted to an annual immunization policy for COVID-19. However, in February the CDC recommended an additional dose for adults 65 and older.

It’s still uncertain which vaccine formulation will be the most protective for the fall release. The Food and Drug Administration delayed its meeting for analyzing surveillance data until last week. So a recommendation is still pending while scientists determine the variant most likely to dominate.

Amid all this uncertainty, what makes sense is for people to protect themselves as best they can. In addition to getting the latest vaccine, wearing a well-fitting mask indoors, especially if recovering from COVID-19 symptoms, is crucial.

Staying outdoors or in well-ventilated areas is advisable — and it suits summer activities well, besides. Those who get sick should seek antiviral treatments as soon as possible after symptoms start, to reduce complications.

The hope is that the impact of COVID-19, which still persists, will lessen over time. The reality? We’re not there yet.