Long COVID is best understood as a collection of overlapping symptoms rather than a single post-viral condition, suggests a ...

There's no single definition of seizure clusters, also called cluster seizures. In general, it's a group of seizures that happen more often than you're used to within a certain span of time. Some ...

What is a cancer cluster? A cancer cluster is defined by the Centers for Disease Control as a greater-than-expected number of cancer cases that occurs within a group of people in a geographic area ...