What influences Influenza (causes and symptoms)

Influenza or flu is a contagious respiratory infection that affects the lungs, throat, nose and occasionally, the ears. It usually does not require treatment but Paracetamol can provide relief from most of the symptoms. Rarely, influenza can lead to severe complications like pneumonia, sinus problems and asthma. Annual vaccinations can prevent these complications even if you do get a mild flu.
Causes
The influenza virus is air borne and can be spread through coughing, sneezing, skin to skin contact, or indirect contact like touching a contaminated object. Type A, Type B and Type C influenza viruses affect the respiratory organs.
People with weak immune systems are infected more easily than others- children under the age of 4, people above the age of 60 pregnant women, obese people and those who are suffering from kidney disorders and diabetes are at greater risk of infection. Air pollution also aggravates the problem.
There is also little chance that your body has the necessary antibodies to fight the virus if you have been infected before. This is because the influenza virus modifies constantly and new strains of the virus appear rapidly. So, the antibodies that work against one particular variant do not work effectively against the others. This is why vaccination is also not a foolproof preventive technique against this disease.

Symptoms
The symptoms of influenza begin to show within a few days after infection. In a few cases, the infection may be asymptomatic. When they do show, the symptoms are very common- high fever, shivering, a blocked and runny nose, frequent coughing and sneezing and chest congestion are the predominant signs. In the later stages, there are headaches, body aches, general fatigue, reddened and watering eyes, throat pains and difficulty in speaking.
In the cases where the patient is a child, there are a few other symptoms like digestive and gastrointestinal disorders such as nausea, vomiting, diarrhea and abdominal pain. The last two are especially common in children who have been infected by influenza virus Type B.
Aged people often have low resistance to the virus. This is why the flu quickly escalates and the complications like primary viral pneumonia or secondary bacterial pneumonia. In such cases, there are sever symptoms like breathing problems, the presence of blood in the sputum, red and itchy skin and petechial rashes (caused by minor punctures in the capillary blood vessels). If you wish to discuss about any specific problem, you can consult a doctor and ask a free question.