Pertussis Whooping Cough ไอกรน. Rome Buathong, MD., FETP. Bureau of Epidemiology Department of Disease Control

Transcription

1 Pertussis Whooping Cough ไอกรน Rome Buathong, MD., FETP. Bureau of Epidemiology Department of Disease Control 1

2 Overview Epidemiology Microbiology Clinical presentations Laboratory investigation Treatment Vaccine and its efficacy Outbreak and its guideline Strategies for prevent and control 2

3 Situation of Pertussis WHO reported global picture of pertussis case from member states in ,868 reported cases 89,000 estimated deaths (2008) 83% estimated DTP3 coverage WHO estimated 50 million cases and 300,000 deaths occur every year 3

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6 DALY of Pertussis, WHO 2002 Age-standardised disability-adjusted life year (DALY) rates from Pertussis by country (per 100,000 inhabitants). 6

7 Death from Pertussis, 2002 Pertussis caused 2.5% of all death of children under 15 years old And accounted for 0.5% of all death worldwide 7

8 Situation in USA was the year of epidemic in 50 years 2012 = 13.3 per 100,000 population 8

9 Outbreak in USA 9

10 Outbreak in USA Wisconsin, Vermont and Washington was highest morbidity rate 10

11 Incidence Trend in USA 11

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13 Situation in Thailand, July, BoE received 20 cases report with 2 deaths 6 5 Under reporting from private and university hospitals Median( )

14 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Trend in Thailand 7 Number Pertussis pertussis cases reported during (July) 14 The majority is infant age 1-3 months old (10%)

15 Pertussis case and Pertussis vaccine coverage in Thailand, Age > 35 yrs old population has no immunized Age < 23 yrs old pop has immunized more than 90% Age between yrs old pop has immunized %

16 Part Vaccine 16

17 Microbiology Bordetella pertussis intracellular aerobic bacteria, spec only in human fastidious Gram negative rods (cocco-bacilli) optimum growth o C Virulence factors filamentous hemagglutinin (FHA) Adhesions pertactin (PRN), fimbriae (FIM), tracheal colonization factor, pertussis toxin (PT), endotoxin (lipo-oligosaccharide), tracheal cytotoxin adenylate cyclase toxin Toxins 17

18 Transmissions Transmitted by aerosolized droplets produced from a cough or sneeze direct contact with secretions from the respiratory tract of infectious individuals target is a cilia epithelium at nasopharynx 18

19 Transmissions highly contagious with 80% secondary attack rates among susceptible persons reproductive number is high as thus the herd immunity need to prevent outbreak in the population = 1-1/R0 = 1-1/17 = = 0.95 or 95% immunity 19

20 Transmissions Incubation period approximately 7-10 days, range 4-21 days Persons with pertussis are most infectious during the catarrhal period (URI) and the first 2 weeks after cough onset (approximately 21 days) 20

21 Transmissions Asymptomatic infected people (mostly in adult) can spread to susceptible people but Symptomatic people have more spreading Long-term carriage (e.g., several months) of B. pertussis probably does not occur Vulnerable host Infant age < 1 year Pregnancy 21

22 The source of pertussis cases age < 2 yr in Canada during was (n=430) a sibling in 53%, a parent in 20%, a child relative in 12%, a neighbor in 8%, a day care contact in 3% (Halperin SA, Wang EEL, Law B, et al. Clin Inf Dis 1999;28: ) Transmissions The source of infant pertussis (only in household) in 4 states of the US during 1990s was (n=264) mothers for 32% another family member for 43% ( Bisgard KM, Pascual FB, Ehresmann KR, et al. Pediatr Infect Dis J Nov;23(11):985-9) 22

23 Clinical Presentations Clinical presentations of pertussis divided into 3 stages include Stage 1 - Catarrhal phase Stage 2 - Paroxysmal phase phase Stage 3 - Convalescent 23

24 Clinical Presentations Stage 1 - Catarrhal stage Duration existing : 1-2 weeks (range 4-21 days) Symptoms : common cold-like illness insidious onset mild fever, nasal congestion, coryza, sneezing, nonproductive cough, conjunctival suffusion and tearing for infant ; apnea and respiratory distress 24

25 Clinical Presentations Stage 2 Paroxysmal stage Duration existing : 2-6 weeks (max to 10 wks) Symptoms : paroxysmal cough (red face, engorged neck vein, walleyed) more frequent at night & average 15 attack/24 hrs, exhaustion, unable to sleep, cyanosis inspiratory whoop may absent in vaccinated case post-tussis vomiting for infant ; apneic episode and face turn blue 25

26 Clinical Presentations Stage 3 - Convalescent stage Duration existing : 2 weeks Symptoms : gradually recovery Paroxysmal cough gradually decrease in frequency and intensity within 2-3 wks non-paroxysmal cough will be continues 2-6 wks Over all symptoms duration without complication approximately 6-10 weeks 26

27 Complications Pneumothorax Epistaxis Weight loss Hernia Subconjunctival hemorrhage Subdural hematoma Rectal prolapse Urinary incontinence Rib fracture Pneumonia Otitis media Seizure Hypoxic encephalopathy Death 27

28 Clinical presentations Whooping cough in adult Whooping cough in child Whooping cough in infant

29 Differential Diagnosis Adenoviral respiratory infection - Children present with fever, sore throat, and conjunctivitis Mycoplasmal pneumonia - Patients with mycoplasmal infections have more pronounced systemic symptoms, fever and headache may occur, and rales may be appreciated on chest auscultation Chlamydial pneumonia - Young infants with chlamydial infections present with staccato cough, purulent conjunctival discharge, tachypnea, rales, and wheezing Respiratory syncytial virus infection - Patients present with predominantly lower respiratory tract signs (eg, wheezing, rales) 29

30 Culture Laboratory investigations Nasopharyngeal polyester or rayon swab OR Nasopharyngeal aspirate/wash Nasal and throat swab NOT allow Transported in Amies charcoal transport media or Regan Lowe TM Bordet-Gengou Agar, Regan-Lowe Agar or Charcoal Agar plate GOLD STANDARD Send to lab within 24 hrs Keep cold chain at 4 o C At least 7 days for result 30

31 NP swab and Media for Culture Regan Lowe TM NP aspirate kit Bordet Gengou Agar NP polyester swab + Amies charcoal TM 31

32 Bordetella pertussis colony 32

33 Laboratory investigations Polymerase Chain Reaction (PCR) Real time PCR Nasopharyngeal polyester or rayon swab OR Nasopharyngeal aspirate Calcium alginate and cotton bud NOT allow Nasal and throat swab NOT allow Transported in sterile container without any medium Send to lab within hrs Keep cold chain at 4 o C for Result back in 1-2 days 33

34 NP swab and container for PCR NP rayon swab + Sterile tube NP aspirate kit NP wash + Sterile container 34

35 Real-time PCR result + template + template + template + template + template + template Threshold line Base line Negative control Threshold cycle (Ct) 35

36 Techniques Video demonstration : US CDC ature=iv&src_vid=9fv5jci0bow&v=zqx56lgitgq 36

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38 Treatment & Prophylaxis Duration X X X X 38

39 Treatment For benefit outcome, Treat person aged > 1 year within 3 weeks of cough onset Treat infant aged 1 years within 6 weeks of cough onset TMP-SMZ considered in infant aged > 2 months Macrolides allergy Can t tolerate Macrolides Macrolides-resistant strain B. pertussis 39

40 Vaccine and Its Efficacy 40

41 ว คซ นม 3 กล ม ส งท ต องร เก ยวก บว คซ น 1. Toxoid ทำจำกพ ษของแบคท เร ย (Bacterial toxin) ว คซ นในกล มน ได แก บำดทะย ก และ คอต บ 2. Killed vaccine (inactivated vaccine) เป นว คซ นท ทำมำจำกเช อตำย แบ งเป น 2.1 Whole cell vaccine : Pertussis, IPV, Rabies, Hep A 2.2 Subunit vaccine : Hep B, Influenza, Hib, acellular Pertussis, typhoid ชน ดฉ ด, pneumococcus 3. Live attenuate vaccine เป นว คซ นท ทำให เช ออ อนแรงลง เช น OPV, MMR, VZV, BCG, typhoid ชน ดก น 41

42 Vaccines อะไรก นวะ เยอะไปหมด DTwP =? DTaP =? DT =? dt =? ap =? TdaP =? Tdap =? ข อช วยจำ D ขนำดยำ > d จ งเหมำะก บ EPI d ฉ ดเฉพำะเด กโตและผ ใหญ D และ wp ห ำมฉ ดในเด กโต ( 7 ขวบ) และผ ใหญ DT ฉ ดเด กเล กในกรณ ท ม ข อห ำม Pertussis vaccine (Encephalopathy after immunization) Tdap สำหร บผ ใหญ และ เด กโต 42

43 How it works! Prime = Primary immunization ฉ ดสร ำงภ ม Boost = ฉ ดกระต น เม อเก ดภ ม ค มก นลดลง (waning) ว คซ นแต ละชน ดม Prime ก บ Boost ท แตกต ำงก นไป Tetanus : Prime 3 doses = 0, 1, 6 month(s) Boost every 10 years Diphtheria : Prime 3-4 doses = 2, 4, 6, 18 months for EPI = 0, 1, 2 mo or 0, 1, 6 mo for outbreak control Boost every 10 years Pertussis : Prime 3 doses = 2, 4, 6 months First boost : months and second boost in 4-6 yrs old Boost every 10 years D, T & P สร ำงภ ม ภำยใน 2 wks และ P สร ำงภ ม ได แย ส ด โดยเฉพำะ wp 43

44 Pertussis vaccine Two types of vaccine Whole cell Pertussis : wp Acellular Pertussis : ap Different in efficacy/effectiveness USA revealed wp effectiveness Overall efficacy of wp in different manufactures was 83-98% Efficacy of ap in 4 licensed vaccines ranges from 71-89% Immunity of pertussis is waning within 5-10 years 44

45 Pertussis Surveillance Thai case definition เกณฑ ทำงคล น ก (Clinical Criteria) ม ประว ต กำรไอมำอย ำงน อย 2 ส ปดำห ร วมก บข อใดข อ หน ง ด งต อไปน 1. ไอเป นช ด (paroxysms of coughing) 2. ม เส ยงหำยใจด งฮ บ ระหว ำงหร อหล งกำรไอ (Inspiratory whooping) 3. ม อำกำรอำเจ ยนหล งกำรไอ (post-tussive vemting เกณฑ ทำงห องปฏ บ ต กำร (Laboratory Criteria) 1. เพำะเช อพบ Bordetella pertussis จำกส งส งตรวจ ได แก 1)NASOPHARYNGEAL SWAB 2)NASOPHARYNGEAL ASPIRATION และ 3) COUGH PLATE 2. Detection of genomic sequences by polymerase chain reaction (PCR) US case definition Clinical criteria Cough > 2 wks with one or more 1. Paroxysmal cough 2. Inspire whoop 3. Post-tussis emesis Laboratory criteria 1. Culture positive for B. pertussis 2. PCR positive 45

46 Pertussis Surveillance Thai case definition Case Classification 2.1 ผ ป วยท สงส ย (Suspected case) หมำยถ ง ผ ท ม อำกำรตำมเกณฑ ทำงคล น ก 2.2 ผ ป วยท เข ำข ำย (Probable case) หมำยถ ง ผ ท ม อำกำรตำมเกณฑ ทำงคล น ก ร วมก บม ข อม ลทำง ระบำดว ทยำเช อมโยงก บผ ป วยท ย นย นผล 2.3 ผ ป วยท ย นย นผล (Confirmed case) หมำยถ ง ผ ท ม อำกำรตำมเกณฑ ทำงคล น ก และ ม ผลบวก ตำมเกณฑ ทำงห องปฏ บ ต กำรอย ำงน อยหน งข รำยงำนต งแต ผ ป วยสงส ย US case definition Case Classification Probable case: Met clinical criteria without labconfirmed or epi-linkage Confirmed case: 1. An acute cough illness of any duration that is lab confirmed by culture 2. Met clinical criteria and labconfirmed by PCR 3. Met clinical criteria and epilinkage to lab-confirmed case Notify either probable and confirmed case 46

47 Outbreak and Control Case investigation Contact investigation Outbreak in household Outbreak in school Outbreak in hospital Outbreak in community Special circumstance 47

48 Case investigation Information to Collect: Demographic information Clinical data Complications Treatment Laboratory tests ordered and results Vaccine history Epidemiological information 48

49 Case investigation 49

50 Contact investigation Objective To minimize the transmission To prevent the serious outcome Classification of contact 1. Household contact 2. Close contact in community, school, working place, public area etc. 3. High risk contact in household, community, school, working place, public area, etc. Post-exposure prophylaxis 50

51 Contact Definition Close contact : face-to-face exposure within 3 feet of symptomatic person for more than 60 minutes 51

52 High Risk Contact Definition Infant aged < 1 years Immunocompromised host Chronic lung disease Cystic fibrosis 52

53 Laboratory investigation Who is need to be tested? 1. Pertussis is highly suspected 2. Symptoms compatible with pertussis 3. Acute cough (any duration) and exposure to a case NOTE: lab test in contact who no symptom is NOT benefit 53

54 Household outbreak Once confirmed case occurred, the investigation looking for acute cough illness who had illness before/after the index onset. All active case finding in household must be epilinkage with lab-confirmed case 54

55 Household outbreak Controls 1. Treatment and chemoprophylaxis Case: initial treatment 3 weeks after cough onset show limited benefit Contact: initial chemophophylaxis 3 weeks after exposure show limited benefit but for high risk up to 6 weeks consider benefit Admin Erythromycin 50 mg/kg/day for 14 days in all HH member regardless of vaccine status 2. Vaccination 3. Isolation 55

56 Household outbreak Controls 2. Vaccination All contacts < 6 years of age who have not completed the four-dose series should complete the series with the minimum intervals. Children aged 4-6 years who have completed a primary series but have not received the pertussis vaccination booster dose should be given this dose No role in people who age over 7 years old 3. Isolation 56

57 Household outbreak Controls 3. Isolation It is not recommend to isolate case in household The case should refrain from contact outside the household for the first 5 days of a full course of antimicrobial treatment The case should refrain from contact outside the household for the first 21 days after cough onset in case of not receive antimicrobial treatment 57

58 School or day care settings outbreak DEFINITION OF AN OUTBREAK IN A CHILD CARE CENTER OR SCHOOL Two or more cases clustered in time (within 42 days) and space (e.g., in one child care center or class); the outbreak case definition may be used to count cases if one case has been confirmed Attack rate of pertussis: 1. Daycare range % 2. Elementary school range 5-74% 3. Middle and high school 3-50% 58

59 School or day care settings outbreak Close contacts to observe for acute cough illness and consider chemoprophylaxis can include the following persons: 1. household contacts and family member 2. infants, children, and other individual at high risk to be severe disease 3. caregivers, staff, aides, and volunteers 4. children attending a regular after-school care group or a play group 5. core group of close friends, social contacts, boyfriends or girlfriends 6. students who work closely together 7. students sitting next to a case-patient in school, or in same school or extracurricular activities, including field trips 8. bus seat-mates and carpool contacts 9. contacts at regular social or church activities, or part-time jobs 59

60 School or day care settings outbreak 1. Evaluate Suspected Cases 1.1 Perform collecting sample in a suspected case 1.2 Begin treatment in a suspected case 2. Identify High-Risk Contacts and Close Contacts 2.1 For chemoprophylaxis 3. Initiate Active Surveillance 60

61 School or day care settings outbreak control 1. Treatment & Chemoprophylaxis 1.1 One lab-confirmed case 1.2 Two or more lab-confirmed cases 2. Vaccination Similar mandatory to HH outbreak 3. Exclusion 1. Symptom person must be exclude from school/childcare for 5 days of full course antibiotic Rx 2. Symptom person without antibiotic Rx must be exclude for 21 days after cough onset 3. Not up to date vaccine or not take chemoprophylaxis contacts may exclude from setting for 21 days after last exposure 61

62 School or day care settings outbreak control 1. Treatment & Chemoprophylaxis 62

63 School or day care settings outbreak control 1. Treatment & Chemoprophylaxis 63

64 Hospital setting outbreak 1. Identifying Close Contacts and High-Risk Groups 1.1 Health Care Workers. HCWs should be considered exposed and regarded as close contacts only if the source is a confirmed case. Close contact includes a) activities such as performing a physical examination, suctioning, intubation, bronchoscopy, feeding, bathing, and other procedures requiring prolonged or close interaction. b) working with pediatric patients, particularly in emergency rooms or a hospital ward setting, should be considered at high risk of exposure to pertussis 1.2 Patients : Close contact includes a) patients who have shared a room or common living space with a pertussis case, or b) patients who have been directly cared for by a HCW with pertussis. 64

65 Hospital setting outbreak 2. Treatment & Chemoprophylaxis Similar to above 3. Exclusion 3.1 HCWs : with symptom should exclude 7 days with full course of antibiotic 3.2 HCWs : asymptomatic should under close surveillance 3.3 HCWs : with symptom but can t take antibiotic Rx should exclude 21 days after cough illness 3.4 Patient : symptomatic case should place in droplet isolation room for 5 days of full course of antibiotic Rx 3.5 Patient : with symptom but can t take antibiotic Rx should place in droplet isolation room for 21 days after cough illness 4. Visitor restriction 5. Active surveillance in the hospital for 42 days after onset of case 65

66 Community outbreak DEFINITION OF OUTBREAK IN A COMMUNITY A community-wide pertussis outbreak may be declared when the number of reported cases is higher than what is expected on the basis of previous reports during a non-epidemic period for a given population in a defined time period (i.e., historical disease patterns). A community may range from a greater metropolitan area to a group of counties or a larger region. 66

67 Community outbreak 1. Treatment and chemoprophylaxis Case: initial treatment 3 weeks after cough onset show limited benefit Contact: initial chemophophylaxis 3 weeks after exposure show limited benefit but for high risk up to 6 weeks consider benefit Admin Erythromycin 50 mg/kg/day for 14 days in all HH member regardless of vaccine status 2. Vaccination 3. Isolation 67

68 2. Vaccination Administering DTaP on an accelerated schedule, giving the 1 st, 2 nd and 3 rd doses at 6, 10 and 14 weeks of age with a minimum interval of 4 weeks between doses Administering the 4th and 5th DTaP doses to children aged <7 years at minimum intervals: giving the 4th dose immediately if the child has been exposed to pertussis and at least 6 months have elapsed since the 3 rd dose, the child is > 12 months of age giving the 5th dose if the child is at least fours of age and the child has received at least 4 doses of DTaP 68

69 3. Isolation Symptomatic patients should refrain from public activities and the workplace for the first 5 days of a full course of antimicrobial treatment. Symptomatic persons who do not take antimicrobial treatment should refrain from public activities and the workplace for 21 days from onset of cough. 69

70 Vaccine Summary 70

71 Vaccine Summary 71

72 US Vaccine Formula During spring of 2005, 2 Tetanus Toxoid and Reduced Diphtheria Toxoid and Acellular Pertussis vaccines adsorbed (Tdap) formulated for adolescents and adults were licensed in the United States BOOSTRIX, GlaxoSmithKline Biologicals, Rixensart, Belgium ADACEL, Sanofi Pasteur, Toronto, Ontario, Canada 72

73 Recommendations Adult vaccination, In 2005 ACIP voted to recommend a single dose of Tdap for adolescents aged years adults aged years Cocooning, ACIP recommends that adolescents and adults (e.g., parents, siblings, grandparents, child-care providers, and health-care personnel) who have or anticipate having close contact with an infant aged <12 months should receive a single dose of Tdap to protect against pertussis if they have not received Tdap previously. Guidance will be forthcoming on revaccination of persons who anticipate close contact with an infant, including postpartum women who previously have received Tdap. Pregnancy, third trimester (27 36 weeks gestation) pregnancy, Tdap will be vaccinated 73

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