Definition of masked. 1  1 : marked by the use of masks a masked ball. 2  2 : failing to present or produce the usual symptoms : latent a masked infection a masked virus.
The herpes simplex virus (HSV) is a double-stranded DNA virus with an enveloped, icosahedral capsid. It is a common cause of infections of the skin and mucous membranes, manifesting itself as tiny, clear, fluid-filled blisters usually around the mouth or genitals.
Respiratory syncytial virus (RSV) is a virus that causes respiratory infections. RSV is the most common cause of bronchiolitis (inflammation of the bronchioles within the lungs) and pneumonia among infants and children under one year of age.