Influenza, Bird Flu, SARS & Swine Flu.pptx

airborne diseases

1. Dr. Rahul Netragaonkar Professor Community Medicine Zydus Medical College, Dahod Influenza, Bird Flu, Swine Flu & SARS

2. INFLUENZA

3. An acute respiratory tract infection. Caused by the. influenza virus 3 types A, B & C All known pandemics caused by Type A strain.

4. EPIDEMIOLOGY Truly an international disease. For every 10 to 15 years pandemic occur due to antigenic variation. 1918 - Spanish influenza. 1957 - Asian Influenza 1968 - Hong Kong

5. 21 million people died worldwide mostly due to secondary bacterial pneumonia. Epidemics occur between pandemics at intervals. 2 - 3 years - Influenza A 4 - 7 years - Influenza B

6. UNIQUE FEATURES OF INFLUENZA EPIDEMIC Large number of subclinical cases. High proportion of susceptible population. Short duration of immunity. Suddenness Speed and ease which they spread. Short incubation period.

7. All contribute to its rapid spread. At present 3 types are circulating in the world A(H1,N1) A(H2,N2) B virus. WHO global surveillance identified human infection with a new influenza virus called A (H5,N1) in Hong Kong in mid 1957

8. Bird flu (Avian Influenza) I s a viral infection that infect birds. H5N1 is the most common form of bird flu. It’s deadly to birds and can easily affect humans and other animals that come in contact with a carrier. range of responses from almost no signs of the disease to very high mortality. The incubation period ( 3 to 7 days).

9. In HongKong H5 N1 strain infected human causing 18 cases including 6 deaths. In mid 2003 virus caused largest and most severe out breaks in poultry on record. Since there over 100 cases have been laboratory conformed in 4 Asian countries named, Indonesia, Thailand, Cambodia, Vietnam more than half people died.

10. Avian Influenza Incidence Tracking Map, February 27th, 2006: 45 Countries Have Bird Flu.

11. Mode of transmission Direct or indirect contact with infected live or dead poultry. No evidence – cooked food. No human to human transmission. But mutation – human to human transmission. Host : Usually chickens, ducks, and turkeys. Environmental : Usually winter, Overcrowding.

12. S ymp t oms High grade fever >38 deg. C Cough/sore throat Diarrhea, vomiting, abdominal pain, chest pain and bleeding from nose and gum. Complications : Hypoxemia Multiple organ dysfunction Secondary bacterial and fungal infections

13. Diagnosis Nasopharyngeal aspirate/wash Nasopharyngeal / oropharyngeal /throat swab Paired serum Immuno fluorescent assay (IFA) Viral culture RT-PCR

14. Management General and supportive treatment Hospitalize and isolate Monitor vital signs Maintain ABC Maintain hydration, electrolyte and nutrition Oxygen Fever - Paracetamol

15. T r e a tme n t Oseltamivir – 75mg BD for 5 days After discharge – infection control precautions – 7 days For children less than 12 years – 21 days

16. Chemoprophylaxis Neuraminidase inhibitors : Oseltamivir Amantadine derivatives Amantadine and Rimantadine Above 1 year : 5 mg/kg/ day (max 150 mg) in two divided doses – up to 9 years Above that 100 mg bd daily 5- 8 weeks

17. Prevention and control Early detection and management Containment of transmission Decrease social disruption and economic loss What if human to human transmission occurs??? Social distancing – closure of schools and other institutions – avoid social gathering If large geographical area involved – restriction of travel and trading

18. Prevention and control What if a human case suspected??? Samples – with in 72 hours of illness – within 24 hours to laboratory Chemoprophylaxis What if human case is confirmed??? Isolation of case in a designated hospital Chemoprophylaxis for contacts and health care workers Strict infection control policies in Hospital

19. Recommendations Cover the nose/mouth when coughing or sneezing Perform hand hygiene if contact respiratory secretions and contaminated objects Put on a surgical mask Respiratory hygiene and cough etiquette Use tissue paper to contain respiratory secretions and dispose in the waste receptacle

20. Swine flu Swine flu is a respiratory disease caused by Type A influenza viruses that infect the respiratory tract of pigs. The H1N1 is said to be a new strain of virus that is mostly a combination of human influenza, swine and avian.

21. Mode of transmission H1N1 virus can generally be spread through airborne of droplet transmission. A person with swine flu can be contagious when he coughs, sneezes, or produce droplets that may land on another person’s open surfaces, such as the eyes, nose, or mouth. Improper handling and cooking of pork products from swine infested with the H1N1 virus can also be a way to get the illness.

22. S ym p t oms The symptoms of swine flu in people are similar to the symptoms of regular human flu. fever, cough, sore throat, body aches, runny nose, headache, chills and fatigue. Diarrhea and vomiting, but more manifested by children. Rare cases, progression to pneumonia and respiratory failure, leading to death.

23. Risk factors Average age increasing Median age 12 – 17 for illness. Risk factors contributing to: Serious case : Cardiovascular Respiratory Diabetes Cancer Severe case : Asthma and other respiratory disease Obesity Pregnancy

24. Diagnosis To swine influenza A infection, a respiratory specimen would generally need to be collected within the first 4 to 5 days of illness. However, some persons, especially children, may shed virus for 10 days or longer. Identification as a swine flu influenza A. virus requires sending the specimen to a hospital laboratory for testing.

25. P r e v e n tion Follow precautions for seasonal influenza to control spread of disease. Vaccine approved by US FDA. Priority for vaccination is : Health care workers / pediatric care givers Pregnant women Schools (staff and students) Under age 65 with risk factors

26. P r e v e n tion Wash hands regularly. Avoid contact with infected person. Always use a face mask Keep yourself isolated from people with possible symptoms o f flu. Avoid visiting places with higher possibility of transmission.

27. T r e a tme n t O seltamivir (Tamiflu®) or zanamivir (Relenza®) for the treatment and/or prevention of swine flu infection. Ayurvedic treatments : Septilin. Some vaccines available like Squalene (Side effects: Autism)

28. T r e a tme n t Antiviral drugs are prescription medicines (pills, liquid or an inhaler) that fight against the flu by keeping flu viruses from reproducing in your body. If you get sick, antiviral drugs can make your illness milder and make you feel better faster. They may also prevent serious flu complications. For treatment, antiviral drugs work best if started soon after getting sick (within 2 days of symptoms).

29. ( Severe Acute Respiratory Syndrome )

30. Introduction SARS is a communicable viral disease caused by corona virus type 4. Declared as a “worldwide health threat.” 1 st new disease of 21 st century.

31. Clinical Symptoms Fever, chills Malaise Dry cough Sore throat Myalagia Headache Running nose Soon the patient develops Viral Pneumonia and ARD, terminally kidney failure.

32. Incubation period It lasts for 2 to 7 days based on single exposure cases or well defined cases. 5

33. SARS transmission pattern No evidence of transmission before onset of first symptoms. A few cases thought to have transmitted in the early prodromal period. Those who are very ill or experiencing rapid clinical deterioration, usually during second week of illness, are the most communicable. No evidence of transmission 10 days post-fever resolution.

34. Probable Case 1.A suspect case with radiographic evidence of infiltrates consistent with pneumonia or respiratory distress syndrome on chest x-ray. 2.A suspect case with autopsy finding consistent with the pathology of respiratory distress syndrome without an identifiable cause.

35. Next Pandemic?????