Assessing Under-Reporting of Murine Typhus in Bexar County

1. Assessing Under-Reporting of Murine Typhus in Bexar County By: Jan Dulay Mentors: Marilyn Felkner, DrPH Infectious Disease Control Unit Texas Department of State Health Services Jeff Taylor, MPH Infectious Disease Control Unit Texas Department of State Health Services

2. INTRODUCTION

3. Murine Typhus • Also know as: • Endemic typhus • Flea-borne typhus • Zoonotic rickettsial disease • Caused by: • Rickettsia typhi • Rickettsia felis

4. Classic Vector-Reservoir Cycle • Rat flea • Xenopsylla cheopis • Rats • Rattus rattus • R. norvegicus Photo from: Emer. Inf. Dis.

5. New Vector-Reservoir Cycle • Cat flea • Ctenocephalidesfelis • Opossum • Didelphisvirginiana • New Reservoirs: • cats • house • mice • skunks • dogs • raccoons Photo from: Emer. Inf. Dis.

6. Symptoms

7. Symptoms of Murine Typhus

8. Misdiagnosis It is confused with… • Typical fever • Viral illness • Urinary tract infection • Respiratory illness • Gastroenteritis • Leptospirosis • Brucellosis • Occult bacteremia • Infectious mononucleosis • Kawasaki disease • Bacterial meningitis

9. Diagnosis and Treatment Laboratory Diagnosis • Serology • Indirect Fluorescent Antibody test (IFA) • Latex Agglutination Test (LA) • Complement Fixation Test • Direct Fluorescent Antibody Test Treatment: • Doxycycline • Tetracycline • Chloramphenicol • Supportive care

10. Bexar Murine Typhus in Texas Nueces Hidalgo Cameron

11. Number of Cases of Murine Typhus in Texas per year Number of cases Year

12. Murine Typhus in San Antonio and Bexar County • History of cases in the 1930s-1940s • Geographic proximity to Nueces County • Temperature- rarely gets below 45°F • Opossums and cats • Urban-suburban; urban-rural interfaces

13. Underreporting • Occurs worldwide • Reasons: • Misdiagnosis • Lack of confirmatory lab results • Physicians’ lack of knowledge • Reportable condition • How to report • Belief that murine typhus is not a public health concern

14. Purpose • To assess the under-reporting of murine typhus in Bexar County

15. METHODS

16. Overview of Methods

17. Survey Design • 9 questions • Questions asked: • Patients with fevers of unknown origin • Symptoms • Risk factors • Laboratory tests • Location of where specimens are sent • Treatment • Reporting Pics of Mr. Wes, Mrs. Tabony, Mr. McElwain

18. Study Population • Physicians in San Antonio • Family Practice • Infectious Disease • Internal Medicine • Pediatrics • Retrieved list of physicians from the Texas Medical Board

19. Survey Distribution • 1174 surveys were sent by US mail! • Responses could be sent back by mail, fax, or website • www.typhussurvey.org • 90 follow up phone calls to Infectious Disease and Pediatrics

20. Data Analysis • Microsoft Excel • Epi Info

21. RESULTS

22. Summary of Respondents

23. Response Method 75 % of Respondents 12 9 4 Response Method

24. Percent of physicians responding by specialty Percentage of Physicians Specialty

25. Gender of Responding Physicians and Total Population Female 38% Male 62% N= 1174 N= 100

26. Age Groups of Responding Physicians 35% Number of Responses 26% 20% 19% Age Group

27. Respondents Who Used the Web 0% 15% Number of responses 20% 0% 20% 26% 35% 19% Age groups

28. Definition of FUO • a fever with a temperature greater than 101°F (38.3°C) • continuous or intermittent for at least 3 weeks with no known cause • diagnosis cannot be obtained even after 1 week of inpatient investigation

29. Number of FUO per Week

30. Consider Murine Typhus in the Differential Diagnosis? Number of Physicians 82% 14% 1% 3% Number of Differential Diagnosis

31. Connection between FUO and Murine Typhus? 62 38 31 7 Did not consider murine typhus Considered murine typhus FUO Seen

32. FUO and Consideration of Murine Typhus, by Specialty

33. Frequency of symptoms used to diagnose murine typhus

34. Possible misdiagnosis and underreporting? • Out of the 38 doctors who had patients with a fever of unknown origin, 18 (47.4%) did not know the proper symptoms of murine typhus: • Responded don’t know, fever with rash only, or no fever

35. Physicians who did not know symptoms of murine typhus, by specialty 41% Number of Respondents 31% 29% Specialty

36. Risk Factors for Murine Typhus

37. Knowledge of laboratory tests to order for murine typhus 10 40

38. Knowledge of Which Laboratory to Send Specimens

39. “Don’t Know” Responses to Knowledge of Laboratories, by Specialty 52% Number of Responses 29% 19% Specialties

40. Knowledge of Treatment

41. “Don’t Know” Responses to Knowledge of Treatment, by Specialty Number of Responses 52% 28% 20% Specialty Seen FUO or Dx MT

42. Reporting to San Antonio Metropolitan Health District

43. Barriers to Reporting

44. Indications of Underreporting

45. CONCLUSIONS

46. Conclusions • There is potential under-reporting of murine typhus in Bexar County but additional data would be required to confirm these findings. • Design an intervention that would target multiple physician specialties.

47. Limitations • Biggest limitation- low response rate • Respondents contacted by phone may have used a handbook to answer the questions • List of physicians was not updated • List did not incorporate the subspecialties of physicians

48. Future Studies • More research in finding the best way to contact physicians (either through mail, phone, or web) • Find effective ways to update physicians about reportable diseases

49. Acknowledgements Texas Department of State Health Services • Marilyn Felkner • Jeff Taylor • Mike McElwain • Mike Gilliam • Laura Taboney • Wes Hodgson • Dawn Hesalroad • Sky Newsome

50. Acknowledgements At UT Austin • Leanne Field • Nancy Elder • Diane Kneeland