Is Sinus Infection Contagious?

Some causes of sinus infections are contagious, and others are not.

A sinus infection (sinusitis) is an inflammation of the sinuses and nasal cavity. 

There are two types of sinus infections:

• Acute sinusitis
  • Has a sudden onset 
  • Lasts less than eight weeks, or 
  • Happens no more than three times per year, with each occurrence lasting 10 days or less
• Chronic sinusitis
  • The most common type
  • Lasts long-term - longer than eight weeks, or
  • Happens more than four times yearly, and symptoms last more than 20 days

Some causes of sinus infections are contagious, and others are not. 

Four Causes of sinus infections include:

1. Viruses (most common cause)
2. Bacteria
3. Allergens or pollutants
4. Fungal infection

Viruses and some bacteria that cause sinus infections may be contagious. 

Risk factors for developing sinus infections include:

• Medical conditions that weaken the immune system
  • Patients with HIV/AIDS
  • Leukemia and other cancers
  • Diabetes
  • Cystic Fibrosis
  • Cleft lip or palate
• Allergies
• Asthma
• Use of medications that weaken the immune system
  • Corticosteroids
  • Tumor necrosis factor (TNF) inhibitors
  • Biologics
  • Monoclonal antibodies
  • Janus kinase inhibitors
  • Calcineurin inhibitors
  • IMDH inhibitors
  • mTOR inhibitors
• Smoking
• Older age
• Frequent air travel
• Exposure to atmospheric pressure changes (for example, deep-sea diving)
• Swimming
• Dental disease
• Structural problems with the sinuses
  • Deviated septum
  • Nasal polyps
  • Tumors

Symptoms of sinus infections vary and depend on the cause, whether the sinus infection is acute or chronic, and what parts of the sinuses are affected. If a sinus infection is viral, bacterial, or fungal, the incubation period (the time from when you catch a bug to when symptoms start) varies depending on the causative agent. 

Symptoms of acute sinusitis include:

• Runny or stuffy nose
• Postnasal drip 
• Sore throat
• Pain or pressure feeling
  • Across the cheekbone
  • Around or under the eye(s)
  • Around the upper teeth
  • Earache, or feeling of fullness in the ears
  • Headache in the temple or behind the eye
  • On one or both sides of the face
  • Symptoms worsen when coughing or straining
• Fever 
• Facial swelling
• Dizziness
• Throat itching
• Sneezing
• Loss of sense of smell
• Ringing in the ears (tinnitus)

Symptoms of chronic sinusitis are often the same as those of acute sinusitis, but symptoms last longer and/or are more severe. Additional symptoms of chronic sinusitis may include:

• Pain/pressure that worsens 
  • In the late morning 
  • When wearing eyeglasses
  • When leaning forward
• Chronic sore throat 
• Chronic bad breath (halitosis)
• Chronic toothache or increased tooth sensitivity
• Increased facial discomfort throughout the day 
• Increased cough at night

Sinus infections caused by viruses, bacteria, or fungi can be contagious. 

These germs are transmitted (spread) by droplets in the air after a person who is sick coughs or sneezes. They can also be passed by touching or shaking hands with a person who is sick and has not properly washed their hands, or by touching a surface a sick person has touched, such as a doorknob, table, faucet handle, etc.

When a sinus infection is caused by a virus, treatment is aimed at relieving symptoms and the virus must run its course. If a sinus infection is caused by bacteria, antibiotics may be prescribed. 

Once a person feels better and no longer experiences symptoms, the sinus infection may be considered cured. 

Acute sinus infections often recur. Additional medications used to treat acute sinusitis include corticosteroids, either in oral or nasal spray form.

In severe cases of chronic sinusitis, surgery may be needed to cure the condition. 

Contact a healthcare professional about a sinus infection if you have: 

• Severe symptoms
• Severe headache or facial pain
• Symptoms that improve and then worse again
• Symptoms that last more than 10 days 
• Fever that lasts longer than 4 days
• If you’ve had multiple sinus infections in the past year