influenza, birdflu swine flu sars covid19 .pptx

influenza, birdflu swine flu

1. Influenza, Bird Flu, Swine Flu, SARS, MERS & COVID-19 Dr.Maham Toqir

2. Influenza M ost common acute upper respiratory tract infection B road array of respiratory illness responsible for significant morbidity & mortaility in children Epidemic Disease (types A & B) and Sporadic disease type C) in humans Family of Orthomyxoviridae Single starnded RNA viruses 3 basic types of virus A,B & C Structural & biological similarities, but vary antigenically Surface proteins associated – Hemagglutinin & Neuraminidase Example: Influenza A – H3N2 expresses Hemagglutinin 3 & Neuramindase 2

3. Patho-physio Respiratory transmission Virus attaches & penetrates respiratory epithelial cells in the trachea & bronchi Viral replication - destruction of the host cell Virus shed in respiratory secretions for 5-10 days Highly Contagious Spread via Air-Borne droplets or direct contact with infected secretions C ommon in winter & spring Symptoms start 2-3 days after exposure

4. Genetic Changes in the Flu Virus- What This Means

5. Pandemic 1918-1919 Spanish Pandemic (subtype H1N1) 1957 Pandemic (subtype H2N2) 1968 -1969 Pandemic - Hong Kong (subtype H3N2) Russian Pandemic in 1977 (subtype H1N1) M ost common type A subtypes – H1N1 & H3N2 Trivalent vaccine contains A strains from both along with B strain

6. Seasonal Influenza Compared to Pandemic – Proportions of Types of Cases

7. Clinical Manifestations Abrupt onset of illness Fever ( 39*C – 40*C) & Chills Severe Headache Weakness, Severe Fatigue M yalgias O cular Symptoms : Photophobia Burning sensations Pain upon motion Sore throat ( Pharyngitis ) T achycardia D/T Hypoxia & Fever

8. Subsequent Catharal & Respiratory Symptoms Nasal Congestion Rhinitis Non-productive cough Cough- Related Pleuritic Chest Pain Dyspnea Wheezing & Rhonchi Cervial Lymphadenopathy

9. Influenza in Infants Conjunctivitis Rhinitis & Gastrointestinal Tract Symptoms S epsis-like scenario with Shock C an cause Croup or Pneumonia

10. Complications Primary Influenza viral pneumonia Secondary bacterial pneumonia Croup Myositis Myocarditis Toxic Shock Syndrome Reye Syndrome

11. Reye Syndrome Acute non-inflammatory encephalopathy & hepatic failure Etiology of Reye Syndrome is unknown Occurs after a viral illness ( upper respiratory tract infection, influenza, varicella or gastroenteritis), and the use of aspirin during the illness.

12. Lab Studies Findings of standard laboratory studies are non-specific Viral culture of nasal-pharyngeal samples, throat sample, or both Direct immunofluorescent tests Serologic studies Chest radiography – to exclude pneumonia

13. Prevention WHO determines influenza vaccine contents annually 3 live attenuated virus strains, antigenically represent the influenza strains likely to circulate the next flu season, are included in the formulation each year Vaccination is Recommended : P ersons older than 65yrs P ts with chronic pulmonary, cardiac, metabolic,renal disease & immunosuppression Children & teenagers with long term aspirin use Pregnant women in 2nd or 3rd trimester during the flu season Physicians, nurses, & other health care providers Employees & residents of nursing homes Household members of persons at high risk Providers of essential community services Students and dormitory residents Anyone wishing to reduce risk of influenza

14. People at Risk Elderly > 65yrs Children less than 2 years Certain chronic diseases H easrt except HTN or lung disease ( including asthma) Metabolic disease including diabetes HIV/AIDS other immuno-suppression ( drugs induced) Chronic renal disease Chronic Hepatic disease Pregnant/ Post-partum Hemoglobinopathies Aged younger than 19yrs, receiving long term Aspirin therapy Person who are morbidly obese ( BMI > 40) Residents of nursing homes & other chrnoic care facilities

15. Vaccines: Influvac Fluraix Agrippal Begrivac Vaxigrip Grippol

16. Bird Flu Aka: Avian Influenza Contagious, viral infections Type A strain (H5N1) 15 Subtypes 1918 Flu Pandemic killed more people than WW1 First Isolated from birds in South Africa – 1961 H5N1 was first recognised in 1997 in Hong Kong During the outbreak, 18 people were affected, with 6 death. Outbreak halted by slaughter of chickens 2003, H7N7 Flu- affected poultry flocks in Netherlands, 83 affected & 1 death – halted by culling affected flocks H5N1 recently re-emerged in Asian countries in altered form

17. Clinical Manifestations in Humans H5N1 & H9N2 – mainly infect humans Symptoms: F ever F atigue M alaise M yalgia S ore throat C ough Severe Cases - Pneumonia R are - Conjuctivitis

18. Transmission Water birds act as hosts of avian influenza virus- carry the virus in their intestinal tracts and shedding it in their faeces Infected birds shed virus in saliva, nasal secretions and faeces Remains viable for long periods at moderate temperatures Survives indefinitely on frozen surfaces Can be spread via improper disposal of infected carcasses, manure or poultry products Spread from bird to human is rare - can occur due to contact with droppings of infected birds

19. Prevention Infected birds shed virus in the 1 st two weeks of infections N o contact with newly affected & suspectable birds Prevent direct contact with free-flying birds & protecting domestic poultry from contact with the feces of wild birds Absence of prompt control measures backed with good surveillance, epidemic can last for years All objects located in an infected poultry farm should be cleaned completely and disinfcected

20. H5N1 Bird Flu 1997- Avian subtype H5N1, first detected in Honk Kong T ransmitted to humans from brids More than 240 human cases documented & more than 140 deaths Slight mutation can cause easy transmission between humans

21. Swine Flu? H1N1 (“swine flu”) – virus first detected in US in April 2009 Other Countries- Mexico, Canada.. 2009- SIV strains include influenza C and subtypes of A – H1N1, H1N2,H3N1, H3N2 & H2N3 Zoonotic Swine Flu People with regular exposure to infected pigs at higher risk Meat cooked properly - no risk

22. Clinical Manifestations Fever, Cough, Sore throat, Bodyaches, Headache, Chills, & fatigue Rare- Diarrhoea & Vomiting Severe- Pneumonia & Respiratory Failure or Death W orsens underlying chronic diseases Warning Signs in Children: Fast breathing / Difficulty breathing Bluish or Gray skin color N ot drinking enough fluid Drowsy Irritable Flue-like symptoms improve- then relapse with fever and worse cough Warning Signs in Adults: Difficulty in breathing or SOB Pain or Pessure in the chest or abdomen Sudden Dizziness Severe or Persistent Vomiting

23. Transmission Via Droplets Direct – Person to Person via coughing or sneezing T ouching contaminated surfaces Infected people can infect others immediat e ly before they develop symptoms V irus can survive on surfaces and infect 2-8 hrs after being deposited on the surface

24. Precautions Cover your nose & mouth when you sneeze or cough Wash your hands often Alcohol based hand cleaners Avoid touching your eyes, nose, or mouth A void contact with sick people Isolate at home if infected Reduce crowded area exposure

25. SARS Define: Severe Acute Respiratroy Synsdrme, a viral respiratory disease of zoonotic origin caused by the SARS coronavirus. Inflamed lungs, difficulty breathing November 2002- July 2003, outbreak of SARS in southern China – 8098 cases, 774 deaths reported in 37 countries Airborne virus, spreads via small droplets of saliva – similar to the cold or influenza First severe and readily transmissible disease – 21st century Spreads indirectly via surfaces touched by infected individuals M ost pts were previously healthy – 25 to 75yrs old C ase fatility – 3%

26. Incubation period : 2-7 days ( may extend 10 days) F irst symptom: High Grade fever Primary target: Lung & Intestine Severe lymphocyte depletion Symptoms: Headaches Malaise Muscle pain Chills and Rigors A fter 3-7 days : Lower Respiratory Phase - dry, non-productive cough or dyspnoea (SOB), hypoxemia, pneumonia, and +/- diarrhea 10-20% require intubations WBCs decrease early on & plts are low during the peak

27. Diagnosis CXR: Abnormal with Patchy Infiltrates ELISA PCR Viral C/S Serological testing

28. Risk Factors: Older age Comorbid Conditions: DM, Chronic Hep, COPD A typical symptoms elevated serum LDH Acute Renal Failure Immunocompromised

29. Prevention Negative pressure rooms Hand hygiene Use of P PE Environmental cleaning and disinfection Source control measures Q uarantine I solation Keeping children with symptoms home from school W ashing proper personal items of someone infected with hot water

30. Complications Pneumonia Severe Breathing Problem Respiratory Failure Heart Failure Liver Failure

31. What is MERS? Middle East Respiratory Syndrome Caused by a coronavirus called MERS-COV First reported in 2012 in Saudia Arabia Recent Surge of cases and outbreaks during the Pandemic 2019 Severe Respiratory Illness 3 or 4 people out of 10 reportedly die Transmission: Air-Borne Vaccine for prevention: Novavax- 2013

32. Clinical Manifestations & Complications Symptoms: Fever Cough SOB Complications: Pneumonia Kidney failure Pre-existing conditions: DM Chrnoic lung/Kidney/Heart Diseases Symptoms appear 5 or 6 days after a person iis infected

33. COVID- 19 COVID -19

34. What is it? WHO – Viruses that cause illness ranging from common cold – severe diseases ( MERS & SARS), Novel virus is a new strain not been previously identified in humans Novel virus is responsible for the current outbreak – COVID -19 First reported – Wuhan, China, December 31st, 2019 Declared as a Public Health Emergency

35. Transmission

36. Complications Pneumonia Acute Respiratory Syndromes Kidney Failure Death

37. Prevention Face masks in crowded areas Wash your hands frequently 3 ft distance from individuals who are coughing or sneezing Avoid touching eyes, nose, mouth Isolate if unwell Clean and disinfect contaminated surfaces