Medical staff in Western Australia have been warned after reports of the wrong immunisations being given to patients.

Respiratory syncytial virus, or RSV, is usually mild but can cause severe illness in infants, older adults and people with certain health problems. It affects the nose, throat and lungs.

RSV, or respiratory syncytial virus, typically is a coldlike nuisance, but it can be severe, even life-threatening, for infants and older adults.

A newly configured federal vaccine panel's June 25 action is expected to improve options to protect infants from potentially deadly RSV.