As the world marks five years since the emergence of Covid-19, China is once again at the center of global health attention with an outbreak of human metapneumovirus (HMPV) reported in several ...

Viral or bacterial particles replicate during the incubation stage. The prodromal stage refers to the period after incubation and before the characteristic symptoms of infection occur. People can ...

Eating an unhealthy diet is tied to an earlier first period, a new analysis suggests. The study linked a girl’s first menstrual period — a milestone known as menarche — to what she ate ...