Case Investigation of Avian in Southeast Asia Influenza Overview - PDF document

Rapid Response Team Training 1 Case Investigation of Avian in Southeast Asia Influenza

Overview • Initiating an investigation • Pre-investigation activities • Investigation • Recordkeeping and reporting • Post-investigation activities 2

Learning Objectives Initiating an Investigation • Discuss what makes an avian influenza (AI) case investigation different from investigations of other infectious diseases • Discuss criteria that would initiate an AI case investigation 3

What makes an AI case investigation different 4 from other outbreak investigations? Discussion

What makes an AI case investigation different? • AI is an emerging infectious disease • Can be political • Requires early investigation for early control • Requires working with other parts of ministry or other organizations with whom we do not usually work 5

What criteria would initiate an 6 AI case investigation? Discussion

Case Confirmation • Does reported case actually exist? – Confirm the case is not a rumor – Talk with hospital, doctors, community residents • Does reported case-patient have illness similar to avian influenza? – Signs, symptoms, exposures to avian influenza 7

Investigating a Suspect Case Evidence for H5N1 infection based on – Clinical findings – Epidemiological evidence – Laboratory testing 8

Case Definition Categories of case definitions for avian influenza A/H5 • Patient under Investigation • Possible Case • Probable Case • Confirmed Case 9

Case Definitions for Influenza A/H5 Patient Under Investigation • Any individual reporting: – Fever (temperature above 38º C) And one or more of these symptoms – Cough – Sore throat – Shortness of breath 10

Case Definitions for Influenza A/H5 Possible Case • A “patient under investigation” who ALSO has one or more of the following: – Lab test for Influenza A (not including subtype) – Contact in past 7 days with confirmed case of Influenza A/H5 – Contact in past 7 days with sick birds – Worked in lab where there is processing of samples from persons/animals with Influenza A 11

Case Definitions for Influenza A/H5 Probable Case • Any “patient under investigation” or possible case who ALSO has –In-country laboratory evidence for influenza A/H5 12

Case Definitions for Influenza A/H5 Confirmed Case • Laboratory testing demonstrates 1 or more of following – Positive viral culture for A/H5 – Positive PCR for A/H5 – IFA Test positive for A/H5 – 4-fold rise in A/H5 in paired serum samples 13

14 Pre-Investigation Activities

Learning Objectives Pre-Investigation Activities • Assemble an investigation team • Prepare the epidemiologic, medical and personal protective equipment and supplies required for an outbreak investigation • Advise relevant public health personnel that a case investigation will be conducted 15

Assemble Investigation Team • FETP: – 2-3 Medical Epidemiologists – 1 Veterinary Epidemiologist – 1-2 Senior MOPH Epidemiologists • In the field may be assisted by: – Provincial rapid response team members – Village health volunteers 16

Advise Relevant Personnel of Case Investigation • Veterinary Health Authority • Government Officials • Health Care personnel • Community • Non-governmental organizations • Laboratory 17

Gather Documentation • Information already gathered – Location of case, date of illness onset, clinical or exposure details • List of contacts • Case reporting forms • Standardized questionnaires 18

Gather Resources • People – Local health workers caring for case-patient – Veterinarians, clinical and laboratory experts, support personnel • Ministry of Health – Advice, guidance, additional personnel • World Health Organization (WHO) • Avian influenza references • Other – Transportation – Security – Communication devices 19

Gather Equipment and Supplies • Epidemiological – Reporting forms – Notebook (or laptop) for recording data • Medical – Antiviral medication (if available) • Laboratory – Swabs, needles, cooler, ice, viral transport media 20

Gather Equipment and Supplies • Educational – Brochures, posters, with influenza safety information – Easy to read – Guidelines for contacts, family members • PPE – Masks, gloves, gown, cap, goggles • Decontamination – Solution for decontaminating homes or hospital rooms 21

22 Investigation

Learning Objectives Investigation • Review a case patient’s medical record • Conduct interviews of clinical staff attending the case patient, the case patient, and patient’s family • Conduct environmental survey of the household • Conduct active case finding in the community • Assess possibility of human-to-human transmission 23

Practical Steps • First visit: Hospital where patient was admitted – Review medical chart – Talk to doctors, nurses – Put on PPE – Meet with patient in the room for interview – Remove PPE • Second Visit: Patient’s home – Identify and interview contacts – Environmental assessment 24

Review Patient’s Medical Chart • Demographic information • Medical history • Current medical complaint / symptom history • Physical examination findings • Recommended treatment • Laboratory or other test results 25

Sample Patient Chart: Clinical Information Demographic Information Date: _____ Name __________ Age ____ Gender ___ Occupation_______ Address______________________________________________________ History of Illness Chief Complaint_____________________ Date of Illness Onset _________________ Other Symptoms and symptom onset date: _______________________________________________________ _______________________________________________________ Physical Exam Findings _______________________________________________________ _______________________________________________________ 26

Sample Patient Chart: Clinical Information Demographic Information Date: _Nov 1, 2006 Name _Sok Phhoung_ Age __21_ Gender:_F_ Occupation______ Address___Patang village, Rattanakiri, Cambodia_____________ History of Illness Chief Complaint___Dyspnea_________ Date of Illness Onset ___Oct 27, 2006______ Other Symptoms and symptom onset date: __Fever – onset Oct 25_________________________________ __Cough – onset Oct 25 ________________________________ Physical Exam Findings _Current fever – 39.4°C, Pulse 123 beats/min________________ _______________________________________________________ 27

Epidemiologic Context • Potential exposure to H5N1 – Travel or residence in area affected by avian influenza outbreaks in animals – Direct contact with dead or diseased birds or other animals in affected area – Close contact with a person with unexplained moderate or severe acute respiratory illness – Occupational exposure Warning! Even if NO reports of ill poultry in a province, there could be disease in that area, especially if poultry influenza vaccines are used 28

Sample Patient Chart: Exposure History Contact with ill people? (If yes, date and name, relationship to patient) ___________________________________________ ___________________________________________ Contact with diseased poultry (Live or dead)? (If yes, date and location) ___________________________________________ ___________________________________________ Recent travel? (If yes, date and location) ___________________________________________ ___________________________________________ Other close patient contacts (Household members, close coworkers) ___________________________________________ 29

Use All Information • Clinical signs compatible with avian influenza • History compatible with exposure to avian influenza • 3 or more cases could indicate an emergency • Send samples for laboratory confirmation 30

Interviews Gather information on exposures and other possible cases – Case-patient(s) – Household contacts – Friends and neighbors – Local health care personnel 31

Interview Tips • Collect as much information as possible – Unstructured interviews – Generate list of contacts • Repeat critical questions for accuracy, validity and additional details 32

Interview Tips • Be friendly, but professional • Identify yourself and your institution • Explain purpose of interview • Stress importance of information you will collect • Inform respondents that all information will be kept confidential • If appropriate, conduct interview in private 33

Type of Information to Collect • Demographic information: age, sex contact details • Clinical information: signs & symptoms, physical exam, vitals, date of onset, hospital admission • Exposure history: occupational exposure, travel, animal exposure 34

35 Contact Identification

What is Contact Identification? The identification and diagnosis of persons who may have come into close contact with an infected individual 36

Purpose of Contact Identification • Find new cases that meet case definition • Provide interventions for exposed individuals to decrease risk of illness and interrupt further transmission – Antivirals (Oseltamivir) – Precautionary Information 37