Chile has been hit by its most severe respiratory syncytial virus (RSV) outbreak in years, killing four infants and putting strain on pediatric intensive care unit (ICU) capacity.

Yessenia Sanchez, the mother of one of the infants who died, said she waited from 8:00 a.m. until 10:00 p.m. for an ambulance to transfer her baby to an ICU. In that time her baby had two cardiac arrests, said Sanchez, who is from Quilpe in the Valparaiso metropolitan area.