You cannot catch a sinus infection.
More Info: A sinus infection is caused by the buildup of bacteria inside of the sinuses. The sinuses are lined with mucous membranes and cilia that help to move mucous and bacteria out of the sinuses. If the cilia are not working properly or if the mucous is unable to drain properly, bacteria can build up inside the sinuses, which can cause a sinus infection.
So though you cannot catch a sinus infection, you can catch the cause of the sinus infection such as a cold or fever.
Signs of Sinusitis: Prevention and Treatment ." Medicinenet.com
What Is a Sinus Infection?
A Sinus Infection is an irritation and swelling of the sinuses and nasal passages. There are a variety of symptoms associated with a Sinus Infection such as headache, pressure on the face, aching teeth, cough, sore throat, and draining of the nasal cavities with thick secretions. The sinuses are located on the facial area and are lined with mucous to keep allergens and bacteria from entering the body. Sinus problems are classified in two different ways: Acute which means a sudden onset of symptoms and chronic which is when the difficulties have been on-going. Chronic Sinusitis is the most common.
What Is a Chronic Sinus Infection?
A chronic sinus infection has the same symptoms as an acute sinus infection, but the symptoms last more than 8 weeks or occur more than 4 times in a year. Like the acute sinus infections, the chronic variety is characterized by inflammation of the sinuses and nasal passageways. Symptoms tend to include a headache and localized areas of pressure depending on the sinus cavity or cavities being affected. Other symptoms may include nasal congestion, mild fever, and a cough.