1. A resource- and labor-intensive county-wide outbreak of pertussis, Wisconsin, 2003-2004: high impact on the adolescent population. Mark J. Sotir 1, Diane L. Cappozzo 2, Carol E. Schmidt 2, David M. Warshauer 3, Jean Zastrow 1, Tim Monson 3, Jeffrey P. Davis 1 1 Wisconsin Division of Public Health 2 Fond du Lac Health Department 3 Wisconsin State Laboratory of Hygiene National Immunization Conference Washington, D.C., March, 2005

2. Background Steadily increasing reported incidence of pertussis among adolescents and adults since 1980’s Large community-wide pertussis outbreak in Fond du Lac County, Wisconsin Outbreak interval: May, 2003 and February, 2004 Extensive response from local and state agencies

3. Objectives Describe the epidemiologic features of the outbreak Use data to address current pertussis-related issues

4. Methods Health department personnel conducted patient follow-up Standardized report form to collect data: signs and symptoms, onset dates, intervention dates, exposure source and contact information, antibiotic treatment, vaccination history

5. Methods Nasopharygeal swab specimens: 2 swabs (calcium alginate for culture, Dacron for PCR) Laboratory confirmation: isolation of Bordetella pertussis in culture (C) or positive polymerase chain reaction (PCR) assay Pulsed field gel electrophoresis (PFGE) of isolates

6. Methods CSTE/CDC pertussis case definitions applied Data submitted to WDPH, entered or merged into Excel database, converted to SAS file and analyzed using SAS software (Version 8.2) Incidence calculated using July 1, 2003 population estimates

7. Fond du Lac County pertussis outbreak, cases by age group and cough onset by two week interval, May, 2003 to January, 2004 <10 years 15-19 10-14 >19 Time Period Number of Cases

8. Fond du Lac County, Wisconsin pertussis outbreak, May, 2003 - February, 2004 County population 97296 313 case patients 193 (61.7%) laboratory confirmed 120 (38.3%) confirmed epi-link or probable 159 (51%) female Median age: 14 years (range: 1 mo - 70 yrs) 3 hospitalized (all infants, total 11 days) 0 deaths 37 (12%) of cases associated with high school weight room use, 33 were 15-19 years old, 2 were unvaccinated

9. Case patient clinical data Fond du Lac County pertussis outbreak, 2003-04 Maximum n = 313 Symptom/sign % yes^ Cough99% Paroxysms58% Whoop37% Post-tussive vomiting31% Sleep disturbance89% Encephalopathy 0% Hospitalization 1%* ^Of known responses *Three infants hospitalized for total of 11 days

10. Known vaccination histories (n=193) Fond du Lac County pertussis outbreak

11. Schools with > 1 case of pertussis while in session, Fond du Lac County pertussis outbreak, May, 2003 - February,2004

12. Case patient ages, Fond du Lac County pertussis outbreak, May, 2003 - February,2004 Age group # % < 1 7 2% 2-5 14 4% 6-9 20 6% 10-1413643% 15-19 8427% >19 5016% Unknown 2 1% TOTAL313 10 -19 70% > 10 86% County wide attack rate all ages: 322 / 100000

13. *cases/100,000 population Fond du Lac County, Wisconsin pertussis outbreak, age group specific incidence during the outbreak interval, May 2003-January, 2004 Age (years) Cases/100,000 population

14. *cases/100,000 population Fond du Lac County, Wisconsin pertussis outbreak, age group specific incidence during the outbreak interval, May 2003-January, 2004 Cases/100,000 population Age (years)

15. Positive and total specimens submitted for B. pertussis testing, July,2003-January,2004

16. Fond du Lac County pertussis cases by laboratory confirmation status, 2003-04 Number of Cases Time Period Laboratory confirmed Not Laboratory Confirmed

17. Comparison of PCR and culture for B. pertussis in paired samples, Fond du Lac outbreak, Wisconsin State Laboratory of Hygiene, 2003 Culture PCRPositiveNegative Positive 79 94 Negative 8 40 Equivocal 3 13 PCR sensitivity: 94% Culture sensitivity: 49%

18. PCR and bacterial culture test positivity and concordancy by time between cough onset and specimen collection, Fond du Lac County, WI, 2003-2004

19. PFGE patterns among Bordetella pertussis isolates, Fond du Lac County, WI, July, 2003-January, 2004

20. Median days between events, Fond du Lac County pertussis outbreak, comparison of early and late outbreak cases, May, 2003 - February, 2004

21. Estimated public health, case finding and prevention costs for 313 cases of pertussis, Fond du Lac County, WI, May 2003-February 2004 Cost categories Av cost/case (comment) Lab tests $1032 (2807 NP swab specs @ $115/spec for PCR, culture, admin: Subtotal $323035) Antibiotic prophylaxis $740 (4687 treatments @ $49.43 AWP for azith. Subtotal: $231678) Public health $217 (LHD 900 hrs: $36000 staff time DPH 716 hrs: $31900) Total $1989* *not included: administrative disruption (schools, social, athletic) or PPE

22. Conclusions Large community outbreak, widespread morbidity that was very difficult to control Striking occurrence of pertussis among adolescents. –Impact of illness in two unvaccinated adolescents. –Weight room related amplification of transmission. Mild but not insignificant impact among those recently fully protected Substantial impact on schools and families Substantial impact on the public health and health care communities “Steep learning curve” among clinicians

23. Conclusions (continued) Powerful effect of enhancements in diagnostic technology (PCR) facilitating more sensitive and rapid testing 62% of the reported cases in Fond du Lac County were lab confirmed Focal occurrence in higher risk settings during this community-wide outbreak required sustained, focused control measures (schools, health care settings)

24. Needs National and state guidelines providing clearly stated endpoints and expectations for pertussis prevention and control with consideration of concerns regarding antibiotic resistance and impacts associated with enhanced diagnostic technology Provision of acellular pertussis component containing vaccine for routine booster vaccination in adolescents would be valuable and acceptance is likely to be good. Benefits would be substantial among: families, schools, public health systems, health care systems and insurers, businesses and many other settings

25. Acknowledgements Special thanks to: Warren Post, M D, Kayla Ericksen and Mary Wedig, Fond du Lac, WI Terry Kurzynski, Wisconsin State Laboratory of Hygiene, Madison, WI Mark Wegner, M D, Dan Hopfensperger, Jeff Berg, Jerry Gabor, Andie Newman, DVM, and Cindy Walker, Wisconsin Division of Public Health, Madison, WI

27. Minimum estimated staff-related care and isolation costs at county’s largest health care provider $16,900: Medication for staff (157: illness or contact) $11,000: Laboratory testing- 220 symptomatic staff - all tests negative $1,200: ER or urgent care assessment of illness $49,450: Leave for furloughed staff not est: Cost of replacement workers not est: Cost of personal protective equipment not est: Outbreak- related administrative,infection control staff and PR costs Costs greatly exceed $78000

28. Evaluation of the Economic Impacts of the Fond du Lac County Pertussis Outbreak

29. Overall Costs for 107 Cases of Pertussis, Monroe County, New York, 1989-1994 Cost CategoriesTotal Cost ($) Physician visits Direct14355 Indirect13079 Subtotal27434 Laboratory tests, direct2611 Medications Antibiotics11780 Symptomatic10272 Subtotal22052 Emergency department visits Direct5175 Indirect1845 Subtotal7020 Hospitalization Direct176702 Indirect17066 Subtotal193758 Additional child care3665 Lost workdays124312 Total381052 Pichichero and Treanor. Arch Pediatr Adolesc Med. 1997;151:35.

30. Economic Burden of Pertussis on Adults Through Illness or Child Care Responsibilities AdultFamiliesAverage Workdayswith AddedAdded (No. ofAverageCumulativeChild CareChild Care Families)TotalCosts (%)Costs ($) No (51) NANA654 Yes 1 adult (50)8.340816482 2 adults (4)4435025400 No data (2)NANA NANA Pichichero and Treanor. Arch Pediatr Adolesc Med. 1997;151:35. Lost Workdays

31. Cost Among Working Parents Days LostWorkingAverageTotal Reason For Per WorkingParentCost PerCost For Work LossParent (mean)AffectedFamily ($)Work Loss ($) Ill family member at home63176723780 Care for hospitalized infant6410254100 Ill family member brought to Physician's office1.7352829881 Emergency department0.75111554 Total38315 Lee and Pichichero. Arch Fam Med. 2000;9:989.

32. Productivity Among 42 Working Parents With No Lost Workdays Duration PerTotal Cost WorkWorkingWorking ParentFor Lost Work Productivity (%)Parents(mean days)Productivity (%) 1001800 75-99164731078 50-7443812546 25-4954024846 <25000 Total68470 Lee and Pichichero. Arch Fam Med. 2000;9:989.

33. Costs for 87 Pertussis Cases, Monroe County, New York Lee and Pichichero. Arch Fam Med. 2000;9:989. AdolescentAdultSubtotal (includingTotal Category (n = 29)(n = 6)infant and child)Cost ($) Medical costs ($)52107 Physician office visit:306040510845 ED visits001303 Hospitalization0020576 Indirect costs for278836914435 visits/hospitalization Subtotal47159 Laboratory ($) Culture377781131 DFA31966957 Serology17068884 Subtotal2972 Medication ($) Antibiotic treatment536991441 Symptomatic1150435 Subtotal1876 Subtotal by age group ($)73681085 Cost per case ($)254181 Parental work loss ($) Loss of work days2378023780 Loss of Productivity6847068470 Additional child care340340 Household prophylaxis12061206 Total145903

34. Estimated case related costs for 313 cases of pertussis, Fond du Lac County, Wisconsin, May 2003-February 2004 Cost categories Av cost/case (comment) MD visits $256* (52% direct) Lab tests $105 (PCR + culture) Medications $206* (1.16 Abx Rx/pt 53 53% Abx 47% Sx) ER/urgent care $66* (74% direct) Hospitalization $141 (3 hosp, 11d) Add’l child care $100 Lost work days $1162* (not include lost productivity) Total $2036 *projected from Pichichero and Treanor, Arch Pediatr Adolesc Med 1997:151:35

35. Estimated case related costs for 313 cases of pertussis, Fond du Lac County, Wisconsin, May 2003-February 2004 med group work adj Age group #costs* total loss** total^ < 1 7 $2822 $19754 2-5 14 308 4312 6-9 20 308 6160 10-14136 254 34544 15-19 84 254 21336 >19 50 181 9050 Unknown 2 306 612 TOTAL 313 95768 TOTAL per case 306 545 1702 * per patient direct and indirect health care, lab and meds based on 1996 costs (Lee and Pichichero, Arch Fam Med; 2000:9:989) ** per patient parent work loss,productivity loss, child care costs expressed as multiplier (1.78) of group med costs ^ group med plus work loss amounts doubled for 2004 cost adjustment

36. Estimated costs for 313 cases of pertussis, Fond du Lac County, Wisconsin, May 2003-February 2004