Just like any another flu, predominantly upper respiratory symptoms like cough, cold accompanied by the usual fever, headache, body ache, loss of appetite, sore throat, weakness, and sometimes uneasy stomach has been reported in many cases.

Mild respiratory illness (nasal congestion, rhinorrhea) without fever and occasional severe disease also has been reported. Other symptoms reported with swine influenza A virus infection include vomiting, diarrhea, myalgia, headache, chills, fatigue, and dyspnea.

Conjunctivitis is rare, but has been reported.

Severe disease (pneumonia, respiratory failure) and fatal outcomes have been reported with swine influenza A virus infection.

The potential for exacerbation of underlying chronic medical conditions or invasive bacterial infection with swine influenza A virus infection should be considered.

People at higher risk of serious complications from seasonal flu include people age 65 years and older, younger than 18 years, pregnant women, people of any age with chronic medical conditions (such as asthma, diabetes, or heart disease), and people who are immuno-compromised (e.g., taking immunosuppressive medications, infected with HIV).

Mortality rate due to the infection is about half of one percent, which is much lower compared to many infective diseases common in day to day life.