It’s impossible to predict with certainty how Covid will affect you if you get infected. Many Covid survivors fully recover within weeks of the onset of their illness, but for others, symptoms linger. Early in the pandemic, it became clear that many people infected with Covid continue to suffer from debilitating symptoms after the acute illness. Many people who initially experienced mild symptoms, or none at all, are suffering from new, returning or ongoing health problems months after their Covid symptoms started.

Their stories are a lesson — and a warning — to us all.

Although we don’t know for…

Although more people are getting the Covid vaccine, the Biden Administration won’t meet its goal of having 70 percent of American adults receive at least one dose of vaccine by July 4 — it will take a few more weeks to reach this level. In communities with high vaccination rates, case counts are falling, businesses are opening safely, and public health measures including mask mandates are being loosened or lifted entirely.

Despite the tremendous decline in Covid cases nationwide, some states are experiencing increases, especially those with lower vaccination rates. The risk-level tracker developed as a collaboration between by our…

In the United States, most adults are now fully vaccinated, and hundreds of thousands more people are getting vaccinated every day. Covid case counts are falling, often dramatically, in communities with high rates of vaccination. The risk-level tracker that our group, Resolve to Save Lives, developed with the New York Times now shows many areas of the country in yellow or green — low or moderate risk of Covid — for the first time since the pandemic started.

People have started traveling again, many businesses, schools, and offices have reopened, and large gatherings are being held. In New York City…

As predicted and feared, viral variants are now causing many of the new cases of Covid disease in much of the world. The Delta variant (B.1.617.2), which appears to have spread widely in India starting last October, appears to be extremely transmissible and might cause more severe illness. The more transmissible the virus, the more people will get sick — and more people will die.

The Delta variant is at least partly responsible for the recent large and deadly wave of cases that overwhelmed health care systems in India. Delta is now spreading in at least 62 countries, including the…

For more than a year, most of the world has been outmatched by Covid. Now we have a powerful tool that’s the only way out of the pandemic: vaccines.

Covid vaccines were a true breakthrough, the result of dazzling scientific progress, substantial investment, and some plain old good luck. The vaccines are safe and more effective than many public health professionals dared to hope early in the pandemic. Covid vaccines were ready quickly, but they weren’t rushed — no corners were cut on safety in the development of these vaccines. …

After receiving a Covid-19 vaccine, many people may experience minor adverse effects such as fatigue or headaches, which generally last around 24 to 48 hours. These reactions can be a sign that the immune system is working and responding to the vaccine. But what does this say about (or to) people who do not experience any side effects? Does an absence of adverse effects mean the vaccine did not work?

Because adverse reactions to the vaccine are more likely to be reported, some people who have not experienced side effects may be worried that they are not as protected as…

Almost 150 million doses of Covid vaccine have been administered in the United States. Most adults are now at least partially vaccinated, and more and more people are choosing to get vaccinated every day. But some people may be wondering if their second shot is necessary. The answer is yes.

If you got one dose of an mRNA vaccine (Pfizer or Moderna), don’t skip the second dose. Without it, your vaccine-induced protection won’t be as strong or long-lasting. The second dose greatly reinforces the protection your immune system started building after the first shot.

With new variants in the mix…

Because of Covid-19, awareness of epidemiology and public health has blossomed this past year. With this increased focus has come increased criticism: never in our lifetimes has there been as much controversy about public health action.

Few Americans question the role of government in preventing the sale of contaminated food, providing safe drinking water, reducing alcohol-impaired driving, or protecting workers and communities from industrial toxins — all of which are matters of public health. Control of infectious diseases is the reason public health practices were developed in the first place.

Good governance matters

Covid has shown the importance of good…