September 30, 2023

Influenza (flu) Symptoms, Causative agent, control, transmission

Influenza (flu) Symptoms, Causative agent, control, transmission

Influenza: (flu)

Causative agent: Influenza virus (A, B, C Strains). Type A is the most severe type 

Image result for influenza


Seasonal epidemics and rare pandemics are frequent features of influenza. Flu seasons generated by IAV and IBV account for the majority of the burden of influenza. HINI and H3N2 are IAV subtypes that now circulate in humans and cause seasonal influenza. Children are disproportionately affected, but the elderly, the very young, and the immunocompromised are at the highest risk. In a typical year, influenza viruses infect 5-15 percent of the world’s population, resulting in 3-5 million cases of severe sickness and 290,000 to 650,000 fatalities from respiratory illness. The number of influenza cases recorded is frequently substantially lower than the number of cases that exist.The number of influenza cases in temperate zones varies from season to season. Seasonality is more complicated in tropical and subtropical countries, and it appears to be influenced by a variety of climatic elements such as minimum temperature, sunshine, maximum rainfall, and high humidity.

Because IAV and IBV circulate together, their transmission patterns are similar. Flu outbreaks generated by new influenza viruses are not uncommon. Novel influenza viruses can spread quickly and trigger pandemics with millions of deaths, depending on the amount of pre-existing immunity in the population. From 1700 to 1889, influenza pandemics occurred around once every 50-60 years, and all known flu pandemics have been triggered by IAVS. Pandemics have emerged around once every 10-50 years since then, suggesting that they may be becoming more common over time.

Mode of Transmission:

  1. Respiratory tract infection 
  2. Droplet infection 
  3. Droplet nuclei ( trough coughing, sneezing, talking)
  4. Fomites (Cups, handkerchiefs, toys, etc.) recently contaminated by the virus.

Incubation period: 1-2 days


  1.  Fever
  2.  Cough
  3.  Malaise (A general feeling of being unwell).
  4.  Sudden onset of chills 
  5. Muscular pain.

Common complications observed are: pneumonia, bronchitis etc. if proper care is not taken.


  1. Daily and immediate reporting to DGHS (New Delhi)
  2. Diagnosis through laboratory confirmation
  3. Checks at the airport.
  4. Isolation of patients in a well ventilated area.
  5. Awareness about the diagnosis and treatment.
  6. Administration of vaccine (influenza virus vaccine trivalent) the vaccines available are: killed virus, live attenuated virus, split virus, recombinant virus.
  7. Washing hands with soap or sanitizer.
  8. Sneezing, coughing and spitting in public places should be avoided.
  9. Saline gargles should be done regularly.
  10. Covering mouth with handkerchief or tissue.
  11. The fomites, room, clothing and bedding used by the patient should be regularly disinfected.
  12. Use of antiviral drugs (Amantadine, Rimantadine)     
  13. For fever symptoms use analgesic and antipyretic drug e.g. Paracetamol

F Y D Pharm Notes, Books, Syllabus, PDF, Videos

S. No.Name of the Course
1.ER20-11T Pharmaceutics Theory
2.ER20-11P Pharmaceutics Practical
3.ER20-12T Pharmaceutical Chemistry Theory
4.ER20-12P Pharmaceutical Chemistry Practical
5.ER20-13T Pharmacognosy Theory
6.ER20-13P Pharmacognosy Practical
7.ER20-14T Human Anatomy & Physiology Theory
8.ER20-14P Human Anatomy & Physiology Practical
9.ER20-15T Social Pharmacy Theory
10.ER20-15P Social Pharmacy Practical
F Y D Pharm Syllabus

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