The vast majority of sinus infections, also called sinusitis, are viral and will go away all on their own, especially if you’ve had symptoms for less than two weeks. Bacterial sinusitis usually occurs as a later complication of viral sinusitis.
In this article, we discuss if sinus infections are contagious, what causes them, and how they spread. Lastly, learn what you can do to treat your sinus infection and when it’s time to see a doctor.
Are Sinus Infections Contagious?
Sinus infections are contagious, however, depending on the underlying cause, you may pass on the organism that caused your infection. In other words, if the source of your sinus infection is a virus, you can pass that virus on to another person. That person may then become sick with a cold but they may not, however, get a sinus infection.
Sinus infections occur when fluid builds up in your sinuses. Behind your nose, cheekbones, and eyebrows, your face holds several air-filled pockets which are your sinuses. Typically, air flows freely through your sinuses and small amounts of mucus catch dust, pollen, and other things in the air to prevent them from entering your lungs.
Sometimes however, your sinuses may fill with extra mucus creating an environment where viruses or bacteria can grow. When allowed to grow, these viruses or bacteria can cause a sinus infection. Viruses are the most common cause of sinus infections, making up about 90-95% of those infections.
What Causes Sinus Infections?
The most common cause of sinusitis are viral respiratory infections that lead to swelling and irritation of the sinuses, the most frequent being the common cold.
Other ways to contract a sinus infection include:
- Nasal polyps, or small growths in the lining of the nose, that may be asymptomatic but block the normal sinus pathways
- Any structural change to the nasal cavity, such as a deviated septum or history of sinus or nose surgery
- Hay fever (seasonal allergies or “allergic rhinitis”) causing swelling to the nose’s lining, usually during common allergy seasons
While sinus infections are common and most adults will experience one over their lifetimes, there are outside influences that can lead to more frequent cases of sinusitis.
Risk factors for an increased chance of a sinus infection include:
- A lasting cold
- Smoking or exposure to secondhand smoke
- A broken nose or other structural problems within the sinuses
- A weak immune system, or starting the cycle of a new drug that weakens the immune system
How Do Sinus Infections Spread?
Sinusitis generally spreads in the same way a cold or flu does. Particles and droplets containing viruses become airborne after a person coughs or sneezes, and those germs then spread to others.
These viruses can also be passed by physical touch. Surfaces like doorknobs can become a carrier for a virus if a sick person touches it.
That’s why actions like washing your hands with soap and water, covering your mouth when you cough or sneeze, and avoiding close contact with others are important steps to prevent spreading your virus to others.
But even with the most stringent precautions, sinusitis is common enough that infections still spread fairly easily. How long are sinus infections contagious? When caused by a viral infection, a person will generally feel symptoms for 7-10 days.
In these cases, they will be contagious with the underlying virus for two weeks, from a few days before they have symptoms until after the symptoms are gone. Allergic sinusitis, and bacterial sinus infections that occur after a virus, are not contagious to others.
Sinus Infection Symptoms
Common symptoms of a sinus infection include:
- Stuffy nose
- Runny nose
- Facial pressure or pain
- Post-nasal drip
- Sore throat
- Bad breath
Fortunately, most sinus infections disappear without needing any prescription medication.
The majority will respond well to over-the-counter (OTC) treatments with time. Without the use of antibiotics, close to 50% of all cases improve within a week, and 70% resolve within two weeks.
There are several ways to help speed up this process with home remedies, while relieving pressure and pain from the sinuses:
- Applying a warm compress: Place this over the nose and forehead.
- Using decongestant nasal sprays: These can help drain and dry up the pooled mucous. Use oxymetazoline (Afrin) twice a day for 3 days only (avoid if you have high blood pressure), or fluticasone (Flonase) twice daily for as long as you’re having symptoms.
- Saline nasal sprays and rinses: These can help clear and thin pooled mucous, preventing bacterial infection and relieving symptoms. You can use these several times per day.
- Inhaling steam: This can be done either with a bowl or in a warm shower.
- Avoiding polluted air, cigarette smoke, or anything else with air contaminants: These can all irritate and inflame the lungs and nasal passages.
- Using a humidifier: Adding moisture to the air can provide relief.
- Drinking plenty of water and resting.
- Using an OTC nasal decongestant: These OTC medications can provide a short-term way to improve symptoms, but should not be used for more than three consecutive days.
- Taking acetaminophen or ibuprofen with or without an added decongestant: These OTC medications can be effective for sinus headaches and discomfort.
- Taking Robitussin or Mucinex: Look for the active ingredient guaifenesin. These medicines can help to thin mucus and decrease coughing.
When To See a Healthcare Provider
While most sinus infections will go away on their own without antibiotics, some patients will need to see a healthcare provider for prescribed antibiotics or other solutions to beat the infection.
You should seek medical care after experiencing any of the following:
- Severe headaches or intense facial pain that do not improve with appropriate doses of ibuprofen and acetaminophen and decongestants
- Symptoms that get worse after initial improvement
- Symptoms that persist 10 or more days without improvement
- Fever over 100.4° F lasting longer than three days
- Fever above 102° F (38.8° C)
- Problems seeing, double vision, or severe swelling and redness around the eyes
- Multiple sinus infections over the course of a year
Frequently Asked Questions
K Health has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references.
Sinus Infection (Sinusitis). (2019).
Current Concepts in Adult Acute Rhinosinusitis. (2016).
Sinusitis Statistics 2020-2019 – Sinusitis Facts and Data Trends. (2020).
Viral Sinus Infection vs Bacterial Sinus Infection, What’s the Difference? 2019.