How do viruses get into cells? Their infection tactics determine whether they can jump species or set off a pandemic

Surface proteins on a virus enable it to attach to and get inside a cell to start replicating. koto_feja/E+ via Getty Images

COVID-19, flu, mpox, noroviral diarrhea: How do the viruses that cause these diseases actually infect you?

Viruses cannot replicate on their own, so they must infect cells in your body to make more copies of themselves. The life cycle of a virus can thus be roughly described as: get inside a cell, make more virus, get out, repeat.