This document provides an overview of avian influenza, including its history, types, epidemiology, pathogenesis, clinical features, diagnosis, treatment, vaccination, and prevention/control. Some key points include: - Avian influenza was first recorded in Italy in 1878 and there have been several global pandemics, including the deadly 1918 Spanish Flu. - It is caused by influenza A viruses that can infect multiple species like birds, pigs, and humans. The H5N1, H7N9, and H9N2 subtypes pose the greatest risk to humans. - Humans usually get infected through direct contact with infected birds or contaminated environments. Signs can range from mild to severe pneumonia and

1. 1
Avian
Influenza
2/7/2018
Presenter: Dr. Bushra Jabeen
Moderator: Dr. S. P. Suryanarayana

2. Contents
1. History
2. Trends
3. Reasons for re-
emergence
4. Types
5. Epidemiology
6. Pathogenesis
7. Clinical features
8. Investigations
9. Treatment
10. Vaccines
11. Prevention and
control
12. References
2

3. History
– First recorded in Italy -1878
– Deadly influenza pandemic in 1918  Spanish Influenza
– In 1933, the first human influenza virus isolated – Ferrets
– Fowl plague  Typhus Exudatious Gallinarum  HPAI (1955)
– 1957  Asian Influenza
– 1968  Hong-Kong Influenza (18 cases and 6 deaths)
– 1997-2003  HP form of Avian influenza H5N1
3

4. Trend of Influenza 4

5. Introduction
– Bangladesh, China, Cambodia, Egypt, India, Indonesia and Viet Nam.
– Europe - 2010 - wild birds dead in Tyva Republic of the Russian
Federation.
– By 19 August 2011, 565 human cases with 331 deaths (fatality rate
58.6%) - World Health Organization (WHO).
– India remained free from avian influenza till mid February 2006.
– First H5N1 outbreak in state of Maharashtra, Gujarat- 10.44 lakh birds
culled.
5

6. Introduction
– Human infections - direct contact or contaminated environments.
– Avian Influenza Virus Subtypes A(H5N1), A(H7N9), and A(H9N2)
and Swine Influenza Virus Subtypes A(H1N1), A(H1N2) and
A(H3N2).
– Influenza viruses – reservoir = aquatic birds.
6

7. 7Family Orthomyxoviridae
Genus Influenza virus
Types Type A Type B Type C
Sub types or
sero types
17 H and 10 N
Infect multiple species;
Human, Avian, Swine,
equine etc
No subtypes
Infect humans
No sub types
Infect humans
and pigs
Public Health
Importance
Causes Pandemics
Spanish Flu [A (H1N1)]
1918-19;
Asian Flu [A (H2N2)]
1957-59;
Hongkong Flu
[A (H3N2)] 1968-68;
“Swine Flu”
[A (H1N1)] 2009-10
Causes Epidemics,
seasonal Influenza
outbreaks and sporadic
cases.
Causes
Epidemics
Seasonal
Influenza
Causes mild
respiratory
disease
Does not Cause
epidemic

8. Influenza A Virus
Single stranded segmented RNA
16 Hemagglutinin subtypes
9 Neuraminidase Subtypes
8

9. Types of influenza
1. Seasonal
2. Avian
3. Swine/variant
4. Pandemic
9

10. Seasonal Flu
– Viral respiratory illness
– Occurs every year, though from year to year the strains differ
– Most people have at least some immunity to the strains of flu
circulating that cause the seasonal flu.
– Vaccination recommendation: chronic illness, children 6-23
months, pregnant women, people over age 50, and health care
workers.
– Symptoms: fever, headache, extreme tiredness, dry cough, runny
nose, sore throat, and muscle aches.
10

11. 11
Magnitude
of disease

12. Globally
12

13. India
– 2006 – first outbreak – Navapur of Maharashtra
– 2008 – declared itself as free on 4th Nov
– Re emergence in West Bengal in Dec 2008, in Sikkim (2010),
Karnataka (2012)
– After a gap of 14 months since august 2013- outbreak in Kerala
– Latest in Kollam district of Kerala – 25.01.2015
13

14. Reasons for re-emergence
1. Can cross species barrier
2. Antigenic changes
1. Antigenic shift
2. Antigenic drift
3. Absence of cross immunity
4. Rapid mutation
14

15. Avian influenza A viruses
classification.
The categories - molecular characteristics of a virus and the virus’ ability
to cause disease and mortality in chickens in a laboratory setting
– Low pathogenic avian influenza (LPAI) A viruses,
Show no/mild signs of diseases
– Highly pathogenic avian influenza (HPAI) A viruses.
Affects multiple internal organs with mortality up to 90% to100% in chickens,
within 48 hours
15

16. Influenza A H5
– Nine known subtypes of H5 viruses: N1 to N9
– LPAI > HPAI viruses.
– Sporadic H5 virus infection of humans - Asian Lineage HPAI H5N1
viruses
– Human infection  severe pneumonia and mortality > 50%
16

17. Influenza A H7
– Nine known subtypes of H7 viruses = N1 to N9
– Uncommon in humans
– Asian lineage avian influenza A(H7N9) viruses - first detected in
China in 2013 – most common
– Severe respiratory illness and death.
– Other: H7N2, H7N3, H7N7 virus infections  mild to moderate
illness in people.
17

18. Influenza A H9
– There are nine known subtypes of H9 viruses: N1 to N9
– All H9 viruses identified worldwide in wild birds and poultry are
LPAI viruses.
– H9N2 virus –
– Bird populations in Asia, Europe, the Middle East and Africa.
– Rare, sporadic infections - in people - mild upper respiratory tract illness
18

19. Epidemiology of Avian
Influenza
Agent factors
– Agent : Orthomyxoviridae, Influenza type A
– Reservoir : Migratory waterfowl: wild ducks
– Source of infection : case or sub-clinical case
– Incubation : 3 to 5 days (max 21 days)
19

20. Epidemiology of Avian
Influenza
Host Factors
– Age : children, elderly persons above 65 years of age
– High Risk : workers handling poultry in farms, markets and
involved in culling activity, veterinary and health workers and their
family members.
– Immunity : 7-8 days after attack, maximum 2 weeks, after 8-12
months Antibody levels drop.
20

21. Epidemiology of Avian
Influenza
Environmental Factors
– Lakes and wet lands
– Seasonality :
Extreme North India - winter
North (Delhi), Eastern and Western India - Rains
South India - cooler season, during rains.
– Overcrowding : enhances transmission
21

22. 22
Mode of
transmission

23. Mode of Transmission
Avian transmission Among birds Oculo-nasal discharge, faeces,
contaminated drinking water
Avian to human Direct contact with infected
poultry, or surfaces and objects
contaminated
Human to human No definite evidence Respiratory route
International spread Trade in live poultry
Migratory waterfowl Natural reservoir and also most
resistant to infection
23

24. Role of Wild Birds
– Isolates primarily from dead or dying animals
– Some isolates from predator or carrion eating birds (falcons, crows)
– Occur from spillover from infected poultry
– Contact with surfaces that are contaminated with virus from infected birds.
– Responsible for spreading virus within a country or between countries
24

25. 25

26. Bird flu in humans
Not using appropriate PPE who had exposures to:
– Direct physical contact with infected birds or surfaces contaminated
by the viruses;
– Being in close proximity (within about 6 feet) to infected birds;
– Visiting a live poultry market.
Human infection with avian influenza viruses does not occur from
eating properly cooked poultry or poultry products
26

27. 27
Pathogenesis

28. 28

29. 29

30. Clinical features
Incubation period =
2 – 8 days
30

31. Signs and symptoms of Avian influenza A
virus infections in humans-
– LPAI A virus - conjunctivitis to influenza-like illness, lower respiratory
disease (pneumonia) requiring hospitalization.
– HPAI A virus - high grade fever with influenza like symptoms and sore
throat.
– Diarrhea, vomiting, abdominal pain, chest pain, and bleeding from the
nose and gums and sometime neurological changes (altered mental
status, seizures).
– Respiratory distress, a hoarse voice, and a crackling sound during
inhalation.
31

32. Laboratory investigations
1. Specimen – nasopharyngeal aspirate (within 3 days of the onset of
symptoms)
2. Antigen detection (15-30 min)
In nasal secretions – immunofluorescence test or ELISA
3. Isolation of virus (2-3 days)
Egg inoculation or cell culture
4. Polymerase chain reaction (hours)
Primer set specific for the Haemagglutinin (HA) gene
32

33. Chest X-Ray changes
– Diffuse, multifocal or patchy infiltrates, interstitial infiltrates
– Segmental or lobular consolidation with air Bronchograms
 Respiratory distress
 Respiratory failure within 1 week.
33

34. In India, facilities for isolation of
the influenza virus:
1. Government of India Influenza Center, Pasteur Institute, Coonoor,
South India.
2. Haskine Institute, Mumbai.
3. School of Tropical Medicine, Calcutta
4. All India Institute of Medical Sciences, New Delhi.
5. National reference lab – NIV Pune
6. National centre for disease control – NCDC Delhi
34

35. Other regional institutes
– National institute of communicable diseases (NICD) – Delhi
– Kings institute of preventive medicine (KIPM) – Chennai
– Virology section, dept. of microbiology – AIIMS, New Delhi
– National institute of Cholera and Enteric diseases (virus Unit) –
NICED, Kolkatta
35

36. 38
Management

37. Treatment
– Neuraminidase inhibitors - Oseltamivir and Zanamivir
– The efficacy depends on their administration within 48 hours after
symptom onset.
– M2 inhibitors - amantadine and rimantadine - pandemic influenza.
39

38. 40
Prevention
and control

39. 41

40. Prevention
– Vaccination and the use of antiviral drugs
– Influenza surveillance,
– Surveillance for severe acute respiratory infections (SARI) and influenza
like illness (ILI).
– WHO with global health partners and agencies, including the World
Organisation for Animal Health (OIE), and the Food and
Agriculture Organization of the United Nations (FAO)
– Others: dept of animal husbandry, dairying and fisheries, ministry of
agriculture and farmer welfare.
42

41. KILLED VACCINES
– Most influenza vaccination programs make use of inactivated
vaccines.
– Subcutaneous route.
– A single inoculation (0.5ml)
– The protective value - 70 to 90 per cent
– Immunity for – 3 to 6 months.
– Re–vaccination on an annual basis is recommended.
– Fever, local inflammation at the site of injection
43

42. LIVE ATTENUATED VACCINES
– Based on temperature–sensitive (ts) mutants
– Administered as nose drops
– Stimulate local as well as systemic immunity
44

43. Newer vaccines
– Split virus vaccine : requires several injections
– Neuraminidase specific vaccine
– Recombinant vaccine
45

44. Chemoprophylaxis
• Neuraminidase inhibitors
• Oseltamivir
• Close contacts – 75mg OD -7 days
• Community contacts – 75 mg OD –
6 weeks
• Amantadine derivatives
• Amantadine and Rimantadine
• Above 1 year
• 5 mg/kg/ day (max 150 mg) in two
divided doses – up to 9 years
• > 9 yrs- 100 mg BD daily
• 5- 8 weeks
46

45. NATIONAL INFLUENZA
PANDEMIC COMMITTEE
1. To establish institutionalized mechanism for policy development for
Avian Human Influenza.
2. Inter-sectoral command and control
3. Coordination with international agencies
4. Formulating advisories on technical matters
5. Activate the contingency plan
47

46. Constitution
1. Secretary, Ministry of Health & F.W. - Chairman
2. Secretary, Department Animal Husbandry & Dairying, - Member
3. Director General of Health Services - Member
4. Director General, Indian Council of Medical Research - Member
5. Director, National Institute of Communicable Diseases - Member
6. Animal Husbandry Commissioner, Department of Animal Husbandry,
Dairy & Fishery - Member
7. Joint Secretary (DM),Ministry of Home Affairs - Member
8. Additional Secretary (DG), MOHFW - Convener
48
NATIONAL INFLUENZA PANDEMIC
COMMITTEE

47. 1. Surveillance for suspected human cases/health checkup of
cullers/poultry worker.
2. Advice for case management, use of PPE and chemo prophylaxis.
3. Collection and transportation of samples from suspected case to
designated laboratories.
4. Do’s/Don’ts for patients, contacts, visitors, travelers and health care
providers
49
NATIONAL RAPID RESPONSE
TEAM

48. NATIONAL RAPID RESPONSE TEAM
Constitution
1. Epidemiologist (2) from NICD
2. Microbiologist from NICD
3. Virologist from NIV Pune/ other ICMR institutions
4. Clinician from central government hospital
50

49. Recognised hospitals in KA
1. Epidemic Disease Hospital, Bangalore
2. Rajiv Gandhi Institute of Chest Diseases
3. District Government Wenloke Hospital, Mangalore
51

50. What to do if a outbreak occurs
in birds???
– Chief veterinary Officer (CVO), District Animal husbandry officer
(DAHO) – each district – alert all veterinary officers – report sick or
mortality
– Ensure that all officers – PPE kits
– Visit the site within 24 hours- receipt of preliminary information
– Disease investigation officer (DIO) – clinical investigation – suspect flu
– inform director animal husbandry.
52

51. Continued…
Identification of alert zone – 10km radius
Collection of samples – high security animal disease laboratory
(NIHSADL) – Bhopal – confirmation
Restriction in alert zone
Outbreak confirmed – 3km radius – culling
Poultry shops – closure – 10km radius
Limited access to infected premises
53

52. Continued…
– Disinfection of surfaces
– Notification to health authorities
– Vaccination of birds – 3-10 km zone
– After a period of 3 weeks – trade
– Random clinical and virological and serological – fortnight – two
months
54

53. What if a human case suspected?
– Samples – with in 72 hours of illness – within 24 hours to
laboratory
– Triple packaging
– PPE while taking sample
– Chemoprophylaxis
55

54. 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
56

55. 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
57

56. Role of health education in
prevention and control
 Reduce exposure risk.
Stringent sanitary measures and appropriate bio - security practices
control of human traffic and introduction of birds of unknown disease
status into the flock.
Carcasses of suspected and confirmed poultry case of Influenza should
preferably be incinerated or buried deep using lime and soil in the ratio of
1 : 3.
Not transmitted to humans through properly cooked food.
58

57. 59
Recent
updates

58. "India has declared itself free from Avian Influenza (H5N8 and H5N1)
from June 6, 2017 and notified the same to the World Organisation for
Animal Health", said the Union agriculture ministry in a statement on
Thursday.
The ministry said that all the outbreaks of Avian Influenza were notified
to the world body and the control and containment operations were
carried out as per the action plan on preparedness, control and
containment.
"Surveillance was carried out throughout the country and around the areas
of the outbreaks since completion of the operation (including culling,
disinfection and clean-up). Surveillance in the states showed no evidence
of presence of Avian Influenza virus", said the ministry while justifying
its action.
60

59. BENGALURU: One case of H5N1 Avian Influenza (bird flu) was
detected in chicken at a poultry shop in Dasarahalli on Kempapura Main
Road.
61

60. CDC Recommendations
62
– Travelers to countries with known outbreaks of Asian H5N1 influenza
should avoid poultry farms, contact with animals in live food
markets, and any contaminated surfaces.
– People should avoid wild birds and observe them only from a
distance; avoid contact with domestic birds (poultry) that appear ill or
have died; and avoid contact with contaminated surfaces.

61. – People who have had contact with infected bird(s) should monitor
their own health for possible symptoms and seek medical care.
– People who have had contact with infected birds may also be given
influenza antiviral drugs.
– Health care providers evaluating patients with possible HPAI Asian
H5N1 infection should notify their local or state health departments
which in turn should notify CDC.
63
CDC Recommendations

62. Summary - Avian Flu
– Occur naturally in wild birds (H5N1)
– The virus continues to change, or mutate
– majority of strains do not infect humans.
– can be transmitted from birds to humans and has a high death
rate in people
– no human immunity to H5N1 and no vaccine is yet available for
people
– There is no cure and in birds or people, but some antiviral
medications may be helpful to treat the virus in people.
64

63. References
1. Park K. textbook of preventive and social medicine. 24th ed.
Jabalpur (MP): m/s banarasidas bhanot; 2017. p. 163-8.
2. Bhalwar Rajiv, Vaidya Rajesh, Tilak Rina, Gupta Rajul, Kunte
Renuka. Textbook of public health and community medicine. 1st
ed. New delhi: department of community medicine armed forces
medical college Pune; 2009. p. 1113-5.
65

64. 1. Information on Avian influenza [online]. 2017April 13 [cited 2018 feb 02]; Available
from: URL :https://www.cdc.gov/flu/avianflu/index.htm
2. Influenza (avian and other zoonotic) [online]. 2018 [cited 2018 feb 02]; Available
from: URL : http://www.who.int/mediacentre/factsheets/avian_influenza/en/
3. Influenza [online]. 2018 [cited 2018 feb 02]; Available from: URL :
http://www.who.int/influenza/human_animal_interface/en/
4. Avian Influenza in India [online]. 2009 [cited 2018 feb 02]; Available from: URL :
H5N8 Avian Influenza in India | HealthMap.
http://www.healthmap.org/site/diseasedaily/article/h5n8-avian-influenza-india-
113016
5. Analysis of recent scientific information on avian influenza A(H7N9) virus [online].
2017 feb 10 [cited 2018 feb 02]; Available from: URL : 04/02/2018 WHO | Analysis
of recent scientific information on avian influenza A(H7N9) virus
http://www.who.int/influenza/human_animal_interface/avian_influenza/riskassessme
nt_AH7N9_201702/en/
6. How Infected Backyard Poultry Could Spread Bird Flu to People [online]. 2017 feb
10 [cited 2018 feb 04]; Available from: URL :
https://www.cdc.gov/flu/pdf/avianflu/avian-flu-transmission.pdf
66References

65. Thank you . . .
67