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Introduction
• Bird flu
• Infectious viral disease of birds
• Can affects – large scale poultry
• First outbreak – H5N1 – 1997 – China
• Re-emergence – 2003 and 2004
• Total 668 cases with 393 death (2003-2014) – globally
• Around 60% case fatality rate
• No human cases yet reported in India from 2003
Epidemiology
• Agent
• Influenza virus A
• Subtypes based on Hemagglutinin (HA) protein and Neuraminidase
(NA) protein
• Two categories– low pathogenic and highly pathogenic
• H5 and H7 subtypes – Highly pathogenic avian influenza (HPAI)
• Antigenic shift – reassortment – novel virus – pandemic potential
• Antigenic drift – gradual adaptation of virus to human cells
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
Clinical features
• Incubation period – 2-8 days (7 days – field investigation (WHO))
• High grade fever >38 deg. C
• Cough/sore throat
• Diarrhea, vomiting, abdominal pain, chest pain and bleeding from
nose and gum
• Common feature – LRI – respiratory distress, hoarse voice , crackling
sound while inhaling
Diagnosis
• Nasopharyngeal aspirate/wash
• Nasopharyngeal / oropharyngeal /throat swab
• Paired serum
• Triple packaging system
• Cold chain – 2-8 deg C
• National reference lab – NIV pune
• Regional reference centers
• 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
Management of human avian influenza cases
• General and supportive treatment
• Hospitalize and isolate
• Monitor vital signs
• Maintain ABC
• Maintain hydration, electrolyte and nutrition
• Oxygen
• Fever - Paracetamol
• Specific treatment
• Oseltamivir – 75mg BD for 5 days
• After discharge – infection control precautions – 7 days
• For children less than 12 years – 21 days
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
• Above that 100 mg bd daily
• 5- 8 weeks
Prevention and control
• Contingency plan for management – 2005
• Objectives
• Surveillance
• Early detection and management
• Containment of transmission
• Decrease social disruption and economic loss
Action plan
• Institutional framework
• Surveillance
• Clinical management
• Public health measures
• Logistics and supplies
• Communications and media management
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 with in 24 hours- receipt of preliminary information
• Disease investigation officer (DIO) – clinical investigation – suspect
flu – inform director animal husbandry, collector and others
• Identification of alert zone – 10km radius
• Collection of samples – high security animal disease laboratory
(HSADL) – Bhopal – confirmation
• Restriction in alert zone
• Outbreak confirmed – 3km radius – culling
• Poultry shops – closure – 10km radius
• Limited access to infected premises
• Disinfection of surfaces
• Notification to health authorities
• Bio-security
• Vaccination of birds – 3-10 km zone
• After a cooling off period of 3 weeks – trade
• Random clinical and virological and serological – fortnight – two
months
Advice to people residing in the area
• Avoid contact
• Avoid handling
• Check temperature for next four days of
contact
• Consult a doctor – suspected contact
Suspected case
Fever > 38 deg C
Plus any one
• Muscle ache
• Cough
• Abnormal breathing
• Suspected pneumonia
Plus
• History of contact with infected birds in past 7 days
• Unusual death of birds in past 14 days
• Contact with pneumonia patient
Probable case
• Symptoms like muscle pain, cough , abnormal breathing or pneumonia
• Preliminary test – influenza A but not confirmed – human or birds
origin
• Respiratory failure
• Death
Confirmed case
• One of the following positive
• Positive viral culture for influenza A/H5
• Positive RT-PCR for influenza A/H5
• Positive IFA test using A/H5 monoclonal antibodies
• A 4 fold rise in influenza A/H5 specific antibody titers
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
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
What if human to human transmission occurs??
• Social distancing – closure of schools and other institutions – avoid
social gathering – initial phase
• If large geographical area involved – restriction of travel and trading
Kerala
• 24-11-2014 - director of animal husbandry – reported mass death of
birds in three districts
• Meeting – health secretary - in the evening
• Outbreak area defined – plan for daily action decided - surveillance
and PPE kits
• Alappuzha DMO – focal point for drug supply – neethi, karunya –
locate stocks of oseltamivir and shift to Alappuzha
• Drug manufacturer (Hetero drugs) – contacted – promised to supply
oseltamivir – short term – long term with in 14 days
• Emergency procuirement – MD KMSCL – Hetero drugs – 50,000
capsules
25-11-2014
• Avian flu confirmed
• Action plan for health department
• Procurement of medicines and PPE kits
• Surveillance
• IEC
• Assignment of jobs
• SNO – drug logistics and supervision
• State mass education and media officer- IEC material
• SMO conference – all DMO’s –
• surveillance measures
• Ensure prophylactic oseltamivir and PPE
• Daily reports to IDSP
• Special sensitization – high risk groups
• Check and verify stocks
• Viral transport medium – issued to Alappuzha and PTA DMO
Response…
• November 25th confirmed – avian flu
• Kottayam, Alappuzha, Pathanamthitta
• Around 2 lakh birds culled
• Till December 5th –
• 256575 houses visited
• 944683 people examined
• 2812 – suspected
• No human cases
Summary
• Viral disease – HPAI - birds – rarely humans
• 60% fatality in humans
• Pandemic potential
• Recent outbreak in Kerala
• No human cases reported