Epidemiologists focus on diseases among groups of people. They also study the spread of disease among animals.

The COVID-19 pandemic is interrupting scientific field work across North America, leaving blank spots in important data sets and making it harder to track ecological change.

Frederick Law Olmsted, the designer of many great North American city parks, understood that ready access to nature made cities healthier places to live.

Delaying medical care comes at a cost, both human and financial. The patients some emergency rooms have been seeing are a lot sicker and more likely to need hospitalization.

Symptoms like loss of smell and taste are powerful predictors of COVID-19 infections.

From Nairobi to Los Angeles, pandemic lockdowns have cleared pollution from the skies. But those blue vistas may be temporary, and shutdowns aren't slowing climate change.

Mothers love to be with their children on Mother's Day, but this year, things might be different. A physician walks you through some questions to consider as you decide whether such a visit is safe.