6. Fungus
Pinkeye or conjunctivitis can be caused by a fungus, particularly candida.
The source of the infection may begin with exposure to impure water while swimming or sharing cosmetics with someone who has a fungal eye infection. The fungus may be introduced into the eye from spores that may be present in the air in the spring or the summer.
When the fungus takes hold in the eye, it can cause redness and other symptoms associated with conjunctivitis. This condition can be treated with medication and it is important to get medical attention right away.