With reports of the first human death from bird flu in the US, some Americans are feeling an uncomfortable flashback to the early days of Covid-19, when infectious disease experts were talking about a new virus that was sending people to the hospital with respiratory infections.

Human bird flu cases are increasing across the country. The H5N1 virus primarily infects poultry and mammals but can be transmitted to humans via direct contact with sick animals, per the Centers for Disease Control and Prevention (CDC).