Conjunctivitis can occur from either a bacterial infection or viral infection, although most often it occurs due to a viral infection. Of viral infections, the adenovirus is the most common cause, and often is accompanied by the common cold or other respiratory system infection (e.g., viral sore throat).

Conjunctivitis is easily contracted, generally through direct contact with the virus; for example, coming into contact with rheum (eye crust) or tears of an infected person.
It often spreads in crowded areas such as schools, hospitals, and public transportation. It is more prevalent among children than adults, as children do not take as many sanitary precautions as adults do.

Conjunctivitis can occur in only one eye or can occur in both eyes simultaneously. When both eyes are affected, it generally occurs in one eye first before spreading to the other eye within 2-3 days.
Symptoms include:
 

• Red eyes
• Eye socket pain
• Itchiness and irritation; the feeling that something is in the eye
• Watery eyes
• Swollen eyelids, which can contain small bumps that may spread
• In the event of a bacterial infection, there will be excess rheum when waking up after a night’s sleep

Conjunctivitis generally lasts for about two weeks. Side effects that may occur as it first presents itself include swelling and inflammation of the cornea, which can lead to blurred vision.
If not treated properly, symptoms may persist for up to 1-2 months.

The doctor will perform a thorough eye exam and review the patient’s medical history. If the conjunctivitis is viral, the patient (most patients) may experience symptoms in both eyes along with symptoms of the common cold and respiratory issues.

Conjunctivitis does not need to be assessed in an examination room, with the exception of when symptoms point to another condition; for example, when symptoms indicate varicella zoster virus, the rubella virus, or morbillivirus infection. In these cases, eye secretions must be sent for analysis. 

Conjunctivitis from an infection with the adenovirus is generally not severe, and usually clears up within 1-2 weeks. Patients may use eye drops to relive irritation and other symptoms, and may also apply an ice pack to the affected eye. The doctor may provide medications for symptoms such as fever and sore throat, and antibacterial medications may be given to prevent further bacterial infections.

Non-severe bacterial infections should generally clear up on their own as well, although using antibacterial medications is recommended to help speed up recovery and reduce the chance of spreading.     

Patients should see the doctor if the following symptoms are present:

• Severe eye pain
• Blurred vision
• Eye sensitivity to light
• Severe red eyes
• Small white spots on the cornea   

Do not ignore these symptoms, as they may indicate a severe viral infection. Visit the doctor for a thorough examination, as certain viral infections can be dangerous. For these viral infections, the doctor may prescribe antiviral medications. 

If you contract conjunctivitis:

• Wash your hands frequently
• Avoid rubbing your eyes, as it can further irritate the eye and increase the risk of spreading to the other eye and to others
• Use a soft tissue to wipe the affected eye and dispose of the tissue properly
• Do not use the same eye drops bottle for both eyes; only use eye drops in the affected eye
• Do not share towels, pillow cases, blankets, etc.
• Do not wear contact lenses
• Do not go swimming
• Take off work or school for at least one week, as to not spread it to others
• Rest your eyes as well as your body
• Covering the eye(s) with an eye patch is not necessary unless inflammation of the cornea or soreness develops; sunglasses may be worn as well. However, do not cover the eye for excessive periods.