Pink eye is a highly contagious infection of the eye. It is easily transmitted in shared quarters, and is very much dependent on good hygiene.
The patient may have pus or secretions in the eye. The secretions could be significant enough to glue the eye closed. The eyelids may become red (as the underlying tissues have infection) or swollen. Vision might be slightly impaired from tears and pus.
A red flag is if the infection cannot be cleared up, or if the patient has other critical problems or signs of sepsis.
If the infection is not too severe, eye drops can be used along with other hygiene. If the infection is progressing, the patient may need antibiotic eye drops.
Also, any bedding the patient has used, and anything in communal areas should be washed.