Influenza: Causes, Symptoms and Diagnosis

Claire Johnson, Department of Internal Medicine, University of East London, UK, Email: clairej@ed.ac.uk

Received: 05-Nov-2021 Published: 26-Nov-2021

Introduction

Influenza is a contagious disease caused by flu viruses. Symptoms range from mild to severe and often include fever, runny nose, sore throat, muscle aches, headaches, cough, and fatigue. These symptoms last from one to four days after exposure to the virus. The flu can spread to pneumonia, which can be caused by a virus or a subsequent viral infection. Other infections include acute respiratory distress syndrome, meningitis, encephalitis, and deteriorating pre-existing health problems such as asthma and heart disease. Infectious diseases are usually mild and limited in the upper respiratory tract, but progression to pneumonia is more common. Pneumonia can be caused by a primary viral infection or a secondary bacterial infection. Major pneumonia is characterized by rapid growth of fever, cough, shortness of breath, and low levels of oxygen that cause blue skin. It is more common in those with lower heart disease such as heart attack. People with the virus can transmit the flu virus by breathing, talking, coughing, and sneezing, spreading respiratory. An infected person can become infected by contact with these particles. Breathing droplets are relatively large and travel less than two feet before falling to nearby areas. Aerosols are small and hang in the air for a long time, so they take longer to stabilize and can travel much faster than respiratory drops. People at risk of the flu include health workers, social workers, and those living with or caring for people at risk of the flu. The effectiveness of seasonal flu vaccines varies greatly, depending on the type of vaccine, age, previous infection, and immune function, so vaccinated people can still get the flu. The effectiveness of flu vaccines is considered inappropriate, but vaccination is still beneficial in reducing the mortality rate and hospitalization. The most common side effects of the vaccine include local reaction to the injection site and flu-like symptoms. Flu vaccines are not allowed for people who have experienced severe allergies as a result of the flu vaccine or in any part of the vaccine. As the flu virus spreads to animals such as birds and pigs, preventing the transmission of these animals is important. Water treatment, pets, isolation, vaccination, and animal safety are the main measures used. Placing poultry and piggery on high ground away from crowded farms, backyard farms, live chicken markets, and plenty of water helps to reduce contact with wild birds. Symptom-based diagnoses are fairly accurate in healthy individuals during seasonal epidemics and should be suspected in cases of pneumonia, acute Respiratory Distress Syndrome, Sepsis, or if encephalitis, myocarditis, or fracture of a muscle tissue occurs. Typical methods of collecting samples for testing include swabs on the nose and throat. A flu test is recommended for anyone hospitalized who has symptoms such as the flu during the flu season or who is connected to the flu. In severe cases, early diagnosis improves patient outcome. Treatment for the flu in mild or moderate illnesses is supportive and includes anti-flu medications such as acetaminophen and ibuprofen, taking enough fluids to prevent dehydration, and resting at home. Antiretroviral drugs are primarily used to treat seriously ill patients, especially those with compromised immune systems.

Acknowledgement

None

Conflict of Interest

The authors declare no conflicts.