Influenza : Symptoms, Treatment, And Types Of Flu

Influenza or flu is an infectious disease caused by an influenza virus.The symptoms of influenza typically begin two days after exposure to the virus and most last less than a week.It can be mild to severe.The virus is usually spread through the air from coughs, sneezes and by touching surfaces contaminated by the virus and then touching the mouth and eyes.Antibiotics have no effect on the infection  of influenza caused by a virus.

The symptoms of influenza

• Runny nose
• Sneezing
• Fever
• Headache
• Sore throat
• Muscle pain
• Coughing
• Feeling tired
• Nasal congestion
• Extreme coldness such as chilling, shivering, and shaking (rigor)
• Irritated, Watering eyes
• Redness eyes, skin, face, mouth, and nose
• Petechial rash

The symptoms of influenza for children

• Nausea
• Sneezing
• Vomiting
• Diarrhea
• Abdominal pain

Three types of influenza viruses that affect people

• Influenzavirus A 

This genus has one species, influenza A Virus.The natural hosts for a large variety of influenza A are wild aquatic birds.Viruses are transmitted to other species.It can cause devasting outbreaks in domestic poultry or give rise to human influenza pandemics.It is the most virulent human pathogens among the three influenza types that causes the severest diseases.

The influenza A virus include  :

H1N1 causes Spanish Flu and Swine Flu

H2N2 causes Asian Flu

H3N2 causes Hongkong Flu

H5N1 causes Bird Flu

H1N2 is endemic in humans, pigs, and birds.

The different sites of infection of seasonal H1N1 and avian H5N1 ( shown in red) influencing their lethality and ability to spread.

Avian influenza virus can survive indefinitely when frozen.They are inactivated by heating to 50 C (133 F) for a minimum of 60 minutes, as well as by acids (pH <2).

• Infuenzavirus B

This genus has one species, Influenza B Virus.It almost exclusively infects human.The seal and the ferret are susceptible to influenza B infections.

• Influenzavirus C

This genus has one species, Influenza C Virus.It infects humans, pigs, and dogs.It usually only causes mild disease in children.

Influenza can be spread in three ways

1. Direct transmission : When an infected person sneezes mucus directly into the eyes, nose or mouth of another person.
2. The airbone route : When someone inhales the aerosols produced by an infected person coughing, sneezing or spitting.
3. Transmission through hand-to-eye, hand-to-mouth or hand-to-nose, either contaminated surfaces or from direct personal contact like a hand-shake.

Treatment

• Drink plenty of liquids, get plenty of rest, avoid using alcohol and tobacco for people with the flu.
• Take medications like paracetamol (acetaminophen) for relieving fever and muscle aches associated with the flu.
• Use antiviral drugs against influenza such as

Neuraminidase inhibitors (Oseltamivir and Zanamivir) can decrease the length of  flu time symptoms for less than a day.

M2 protein inhibitors (Adamantane derivatives) inhibit the replication of the influenza A virus.They are sometimes effective against influenza A.

Prevention

• Vaccination provides the best  immunity against the strains of virus.
• The use of alcohol is an effective sanitizer against influenza viruses.
• Avoid close contact with the sick people.
• The use of face mask prevents transmission when  caring for the sick.
• Hygiene habits include frequent hand washing  with soap and water.