Thein Shwe, MPH, MS, MBBS VPD & IBD Epidemiologist Hot Topics Training 11/17/2010 Division of Infectious Disease Epidemiology Office of Epidemiology & Prevention Services Bureau for Public Health West Virginia Dept. of Health & Human Resources 1

Objectives To describe clinical description, diagnosis and epidemiology of pertussis To understand Investigation of a case of pertussis and outbreak of pertussis To review a pertussis case study 2

Disease Description Pertussis, a cough illness commonly known as whooping cough (100 Day Cough), is caused by the bacterium Bordetella pertussis. Prolonged paroxysmal cough often accompanied by an inspiratory whoop. Varies with age and history of previous exposure or vaccination. Neither infection nor immunization provides lifelong immunity 3

Other Bordetella species Three other Bordetella species: B. parapertussis, B. holmesii, and B. bronchiseptica. B. pertussis and B. parapertussis coinfection is not unusual. Disease with Bordetella species other than B. pertussis is not reportable. 4

Clinical Description of PertussisStages (6-10 wks.) Catarrhal (1-3 wks.) Paroxysmal (1-2 wks.) Convalescent (up to 3 mths.) Symptoms mild URT symptoms, mild URT symptoms, intermittent dry cough intermittent dry cough coughing spasms coughing spasms inspiratory whoop inspiratory whoop Post-tussive vomiting Post-tussive vomiting Infants <6 mths. Gagging, gasping or apnea No whoop Prolonged 5

SOUND OF PERTUSSIS 6

Epidemiology of Pertussis Mode of transmission Person to person via Aerosolized droplets from cough or sneeze Direct contact with secretions from respiratory tract of infectious person 80% - secondary attack rate Older children and adults are important sources of disease for infants and young children Infants <12 months of age greatest risk for complications and death 7

Epidemiology of Pertussis cont. Reservoir - Humans Incubation period: 7-10 days (5-21 days). cough onset Infectious period: Most contagious during the catarrhal stage (3 weeks before cough) and the first 2 weeks after cough onset Duration of illness: Children: 6-10 wks. ~ ½ of Adolescents: 10 wks or longer 8

Pertussis Complications Syncope (temporary loss of consciousness/faint) Sleep disturbance Incontinence Rib fractures Complications among infants Pneumonia (22%) Seizures (2%) Encephalopathy (<0.5%) Death Infants, particularly those who have not received a primary vaccination series, are at risk for complications and mortality. 9

Pertussis Laboratory Diagnosis WV OLS offers pertussis PCR and Culture for free of charge

Pertussis Laboratory Testing CulturePCRDFASerology SpecimenNP Swabs or aspirates NP SwabBlood AdvantagesGold standard 100% Specific Results available quickly Rapid results DisadvantagesRelatively insensitive Difficult to isolate Most successful during the catarrhal stage Takes 7-10 days to get the result Sensitivity & specificity varies Calcium alginate swabs cannot be used to collect NP swabs for PCR Not confirmatory No use for surveillance No standardized test available No use for Surveillance CommentsUse with cultureUse with culture and/or PCR NP swab=nasopharyngeal swabs, PCR-Polymerase chain reaction, DFA-direct florescent antibody 11

Proper Technique for Obtaining a Nasopharyngeal Specimen for Isolation of B pertussis 12

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& Outbreak Investigation 14

CDC/CSTE (2010) 15

Pertussis Probable Case Definition - In the absence of a more likely diagnosis, a cough illness lasting ≥2 weeks, with at least one of the following symptoms: paroxysms of coughing; OR inspiratory "whoop”; OR post-tussive vomiting; AND absence of laboratory confirmation; AND no epidemiologic linkage to a laboratory- confirmed (PCR or culture) case of pertussis 16

Pertussis Confirmed Case Definition Option 1 Acute cough illness of any duration with isolation (culture) of B. pertussis from a clinical specimen 17

Pertussis Confirmed Case Definition Option 2 Cough illness lasting ≥2 weeks, with at least one of the following symptoms: paroxysms of coughing; inspiratory "whoop"; or post-tussive vomiting AND polymerase chain reaction (PCR) positive for pertussis; 18

Pertussis Confirmed Case Definition Option 3 Illness lasting ≥2 weeks, with at least one of the following symptoms: paroxysms of coughing; inspiratory "whoop"; or post-tussive vomiting; AND, contact with a laboratory-confirmed (PCR or culture) case of pertussis. 19

PERTUSSIS CASE INVESTIGATION 20

Importance of Rapid Case Identification Early diagnosis and treatment to limit disease spread Identify and provide prophylaxis to close contacts pending laboratory confirmation When suspicion of pertussis is low, investigation can be delayed pending laboratory confirmation Exception: prophylaxis of infants and their household contacts should NOT be delayed 21

What is the next step in a case investigation? Refer to Pertussis Protocol Use Pertussis WVEDSS form Begin your case ascertainment 22

Resources Needed for Case Investigation 23

Resources Needed for Case Investigation cont. 24

Resources Needed for Case Investigation cont. 25

Resources Needed for Case Investigation cont. 26

How do you ascertain a case? Three pieces of information needed to determine if you have a pertussis case 1. Clinical information 2. Laboratory report(s) 3. Epidemiological information 27

Verify the diagnosis Clinical information Cough (yes/no) Duration of cough Paroxysmal cough Post-tussive vomiting Whoop Laboratory informa tion Is laboratory testing done? Type of test Culture PCR Serology 28

Epidemiologic Information Vaccination history Received any pertussis- containing vaccine No. of doses Vaccine date Manufacturer Lot no. Epi-linked (Yes/No) Transmission setting Secondary transmission Contact tracing 29

Management of Close Contact(s) Identify close contacts Prevent secondary transmission Collect nasopharyngeal swab (if not done so) for PCR and culture testing at OLS Treat the patient with recommended antibiotics Isolate the patient for 5 days (after the beginning of antibiotics) or 21 days (if no A/b treatment received) 30

Contact Tracing Close contact definition Direct face-to-face contact for a period (not defined) with a case-patient who is symptomatic during the catarrhal and early paroxysmal stages of infection. All residents of the same household; Daycare and baby-sitting contacts; and Close friends, regardless of immunization status. 31

Contact Tracing Close contact definition (cont.) Shared confined space in close proximity for a prolonged period of time, such as >1 hours, with a symptomatic case-patient: or 32

Contact Tracing Close contact definition (cont.) Direct contact with respiratory, oral, or nasal secretions from a symptomatic case-patient – example: an explosive cough or sneeze in the face, sharing food, sharing eating utensils during a meal, kissing, mouth-to mouth resuscitation, or performing s full medical exam including examination of the nose and throat. 33

Contact Tracing of a Pertussis Case 34

Management for Exposed persons Type of Contact Evaluate & Lab VaccinateProphylaxis/treatment Asymptomatic Within 3 weeks NoYesYes Asymptomatic > 3 weeks NoYes Consider for households with high- risk contacts (infants, pregnant women, people who have contact with infants) SymptomaticYes Collect NP swab YesYes

Postexposure Prophylaxis for Pertussis in Infants, Children, Adolescents, and Adults Source: Red Book 2009 AAP – pg. 507 AgeAzithromycin (Recommended) Erythromycin Recommended Clarithromycin (Recommended) TMP-SMX (alternative) <1mo10mg/kg/day as a single dose for 5 days 40mg/kg/day in 4 divided dosesx14days Not recommendedCI at <2 mo of age 1-5 moSee above 15mg/kg/day in 2 divided doses x 7 days ≥2mo of age:TMP,8mg/kg/da y;SMX,40mg/kg/day in 2 doses x 14 days ≥6 mo or older & children 10mg/kg/day as a single dose on day 1(maximum 500 mg); then 5 mg/kg/day as a single dose on days 2- 5(maximum 250 mg/day) 40 mg/kg/day in 4 divided doses for 14 days (maximum 2g/day) 15mg/kg/day in 2 divided doses x 7 days (maximum 1 g/day) See above Adolesce nts & adults 500 mg as a single dose on day 1, then 250 mg as a single dose on days 2-5 2g/day in 4 divided doses for 14 days 1g/day in 2 divided doses for 7 days TMP, 200 mg/day; SMX,1600 mg/day in 2 divided doses x 14 days TMP- trimethoprin; SMX-sulfamethoxazole; CI - contraindication 36

Once the investigation is completed.. Document public health action Check case classification Print the report for your files or per your LHD policy & procedure Send lab report(s) to DIDE Submit completed WVEDSS report electronically to your regional epidemiologist and DIDE 37

Pertussis Outbreak Case Definition Outbreak is defined as: Two or more cases Involving two or more households Clustered in time & space AND One case must be confirmed by positive culture 38

Pertussis Outbreak Line List Form f 39

Outbreak Notification and Control Notify your regional epidemiologist & DIDE immediately Evaluate case status & manage close contacts Obtain nasopharyngeal swabs for culture (confirmation) and PCR 40

Outbreak Control in Any Settings Treat/Prophylax with recommended antibiotic Isolate 5 days after starting antibiotic treatment or 21 days from cough onset if no treatment Bring immunizations up-to-date Accelerated vaccination if cases are occurring young infants 41

Alert your providers and notify the parents… Healthcare Providers Send Health alert letter Provider information sheet Parent/Guardian Send notification letter Public information sheet 42

Exposures in Child Care Exposed Children (especially incompletely immunized) and childcare providers should be Observed for respiratory tract symptoms for 21 days after contact with an infectious person has been terminated Administer vaccine and antibiotics Exclude: Symptomatic or confirmed pertussis until completion of 5 days of the recommended course of antimicrobial therapy or 21 days if untreated 43

Follow up & Report Check the status of the outbreak control Document and update your regional epidemiologist and DIDE when the outbreak is controlled completely Forward report with lab results to DIDE 44

Case Study On November 1, 2010, an Infection Preventionist (IP) of CAMC called your health department to notify you about two 6-month old twins who presented to the ED with cough for 10 days since 10/22/10, apnea and paroxysmal cough, the labs are pending at this time, the ER doctor had high suspicion of pertussis, both babies were admitted to CAMC, and treated with Azithromycin 10mg/kg/day for 5 days. 45

What would you do as soon as you receive a call like this? 46

What Information would you collect for contact tracing? 47

Contact Tracing Information Six household members and a baby sitter were exposed to these twins during the infectious period. A baby sitter and 5 of 6 household members have been coughing: Amy, mother, 30 yo, cough started on 10/23, no vaccine Bob, father, 32 yo, cough started on 10/24, vaccine yes, # of dose -UK Ann, grandma, 67 yo, cough started on 10/16, no vaccine John, brother, 9 yo, no cough, had 4 doses of PCV Julie, sister, 6 yo, cough started on 10/22, had 4 doses of PCV Brad, brother, 4 yo, cough started on 10/24, had 4 doses of PCV Katie, baby sitter, 19 yo, cough started on 10/10, had 3 doses of PCV 3 siblings attend the same elementary school and have been attending school while coughing. No lab done yet on any symptomatic cases as of 11/1/10 None of them has received PEP yet as of 11/1/10 48

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What is your next step at this time? 50

Do you have an outbreak at this time and why? 51

On 11/2/10 and 11/8/10 Lab results were faxed to your HD: NameSpecimen Source/Date Type of TestResultReference Kevin Smith NP swab 11/1/10 DNA/PCR B pertussis B parapertussis Detected Not detected Kevin Smith NP swab 11/1/10 Culture B pertussis B parapertussis Not isolated Marvin Smith NP swab 11/1/10 DNA/PCR B pertussis B parapertussis Detected Not detected Marvin Smith NP swab 11/1/10 Culture B pertussis B parapertussis Isolated Not isolated 52

Information about Close Contacts All close contacts received PEP. Nasopharyngeal swabs have been taken from all symptomatic contacts for lab confirmation and all were negative for B. pertussis for PCR and culture. All symptomatic contacts had at least two weeks of cough. 53

Case Ascertainment of Close Contacts NameClinical Criteria Lab Criteria Epi-linkedCase Status? Amymetnegativeyes BobNot metNegativeyes AnnMetNegativeyes JohnMetNegativeYes JulieMetNegativeYes BradNot metNot done KatieYesNegativeYes 54

Do you have an outbreak at this time and why? 55

What is your next step at this time? 56

Summary Disease description including clinical characteristics, laboratory diagnosis and epidemiology Pertussis case investigation and outbreak investigation Case study 57

Resources IDEP Pertussis site: CDC Pertussis Surveillance Investigation: manual/chpt08_pertussis.pdfhttp:// manual/chpt08_pertussis.pdf Guideline for Control of Pertussis Outbreak: de.htm de.htm 58

References CDC VPD Surveillance Manual, 4 th Edition, 2008 Pertussis: Chapter 10 Pertussis (Whooping Cough) Pg , Red Book, 2009 Report of the Committee on Infectious Diseases – American Academy of Pediatrics, 28 th Edition schedule.htm schedule.htm Pertussis Pg , Control of Communicable Diseases Manual, APHA & WHO, 19 th Edition, David Heymann, MD, Editor 59

Questions? 60

VACCINATION SCHEDULES 61

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