Influenza Presentation Community Health Nursing

Communicable Diseases

1. INFLUENZA - By Ankita Mitra ( 2 nd BSC)

2. INTRODUCTION During 1918 influenza pandemic, 12 to 13 million people died in India. Influenza is caused by a virus that attacks mainly the upper respiratory track that include the nose, throat and bronchi and rarely the lungs. In India there were 28,798 H1N1 cases, 1218 deaths which equality the death rate 4.2% (2019, National centre for disease control)

3. DEFINITION WHO : I nfluenza is a viral infection that affects mainly the nose throat bronchi and occasionally lungs. Infection usually lasts for about a week and is characterized by sudden onset of high fever, aching muscles, headache and severe mailise, non-productive cough, sore throat and rhinitis

4. EPIDEMIOLOGICAL TRIAD

5. CAUSATIVE AGENT OF INFLUENZA Influenza virus belongs to the family of orthomixoviridae. There are three viral subtypes: * Influenza type A, type B, and type C. Influenza A has 2 subtype which are important for humans: A(H3N2) and A(H1N1) of which the former is currently associated with most deaths.

6. * Influenza viruses are defined by two different protein components, known as antigens on the surface of the virus. They are spike like features all Hemagglutin (H) and Neuraminidase (N) components. H antigen initiats infection and the N antigen releases the virus from infected cell.

7. Birds and animals are considered as the major reservoirs. Usually the source of infection is the case or subclinical case. Virus is present in the nesopharynx of infected person. Period of infectivity is 1 to 2 days before and 1 to 2 day after the onset symptoms.

8. HOST FACTORS OF INFLUENZA Effects all ages and both sexes Highest mortality is found among old people over 65 years, children below 18 months and people with chronic disease like diabetes. Human mobility is major cause of spread of infection.

9. ENVIRONMENTAL FACTORS OF INFLUENZA * SEASONAL : Epidemics takes place in winter in Northern hemisphere and in rainy season in Southern hemisphere. * Overcrowding facilitate transmission.

10. MODE OF TRANSMISSION The virus spread from person to person through droplet infection or droplet nuclei by sneezing, coughing and talking. * Portal of entry : the influenza virus enters the body through the nose and the throat.

11. INCUBATION PERIOD OF THE VIRUS 18 to 72 hours.

12. CLINICAL FEATURES OF INFLUENZA Fever Headache Cough Sore throat General mailise

13. COMPLICATION Bacterial pneumonia Ear infection Dehydration Myocarditis Even heart attack occurs as a complication of influenza

14. PREVENTION Vaccination is the prime measure for preventing influencer and bringing down the impact of epidemics. They are different types of influence a vaccines available and in existence for more than 60 years. It is recommended that elderly person, and the persons of any age who are considered at “high risk” for influenza related complications due to underlying health conditions should be vaccinated. WHO recommended annually a vaccine that targets the 3 most virulent strains in circulation.

15. KILLED VACCINE One dose of vaccine contains 15 microorganism of HA. A single dose of 0.5 ml is given to adults and childrens over 3 years. 0.25 ml is given for children between 6 to 36 months. A single dose of inactivated vaccine annually is appropriate, except for previously unvaccinated preschool children pre existing with medical condition who should receive 2 doses at least one month apart.

16. LIVE ATTENUATED VACCINE Widely used in USSR. Administered as nasal drops.

17. ANTIVIRAL DRUGS Antiviral drugs such as the M2 inhibitors (acting against type type A virus) and the more recently developed neuraminidase inhibitors (acting against both type A and B viruses) have been shown to be effective for treatment ( and for some agents, prophylaxis) and are now available in many industrialized countries. * Presently Amantadine and rimantidine are not recommended for anti-viral treatment or chemoprophylaxis of influenza A because of resistance in circulating influenza A strains.

18. ANTI-VIRAL DRUGS FOR ADULTS Inhaled zanamivir is recommended for treatment of adults with uncompleted acute illness of influenza A or B virus, and for chemoprophylaxis of influenza among adults. Zanamivir is not advised to people with respiratory disease like asthma or chronic obstruction pulmonary disease (COPD).

19. Zaiamivir is given using inhaler device. This is administered as 5mg blister dosage per inhalation. The recommended dosage for influenza is 2 inhalation (10 mg) twice daily 1-2 hours apart. For chemoprophylaxis zanamivir 10 mg is administered (2 inhalation) once a day.

20. ANTI-VIRUS DRUGS FOR CHILDREN Zanamivir is recommended to treat influenza among children aged 7 years and older. Duration of treatment is 5 days. Zanamivir is approved for chemoprophylaxis of influenza among children aged 5 years and older. Treatment and chemopraphylaxis dosing and frequency at the same for children as for adults

21. CONTROL MEASURES FOR INFLUENZA Adequate ventilation required in living rooms. Avoid overcrowded places during epidemics. Stay at home at the first sign of influenza. Infected person should cover the mouth and nose with handkerchief to protect others from infection.

22. CONCLUSION Influenza virus cause the flu. Influenza viruses are spread from person to person by coughing and sneezing. Influenza viruses occurs naturally in birds , but can sometimes be transmitted to humans and other animals. The highly pathogenic Avian influenza viruses can be very dangerous to poultry and humans.