GSK announced on Tuesday that a single dose of its Arexvy vaccine against respiratory syncytial virus (RSV) was 43.3% effective in preventing severe illness three years after patients 60 and older first received the shot.

In most cases, adequate hydration and over-the-counter pain relievers can help manage your symptoms during the week or two it takes to recover from RSV. But children under 5 and adults 60 and older are at high risk of severe infection resulting in hospitalization. The latter are also in danger of death.

Dr. Jaunita Mora said the respiratory syncytial virus is the leading cause of infant hospitalizations. Here are the people she said are most vulnerable to the disease.

RSV hospitalizes thousands of people in the US every year. Three new vaccines could help stem the spread, but there are already huge inequities in access and uptake.