The Trouble with Ticks: Distribution, Burden, and Prevention of Tickborne Disease in Humans

Transcription

1 National Center for Emerging and Zoonotic Infectious Diseases The Trouble with Ticks: Distribution, Burden, and Prevention of Tickborne Disease in Humans Paul Mead, MD, MPH Integrated Tick Management Symposium 17 June, 2016

2 Tick-associated diseases in the United States Anaplasmosis Babesiosis Borrelia miyamotoi infection Colorado tick fever Ehrlichiosis Heartland virus infection IgE-mediated anaphylaxis Lyme disease STARI Spotted fever rickettsiosis Powassan virus infection Tick paralysis Tickborne relapsing fever Tularemia

3 Reported cases of tickborne disease, United States, 2014 Disease Cases Lyme disease 33,461 Spotted fever rickettsiosis 3,647 Ana. phagocytophilum 2,800 Babesia 1,759 Ehrlichia chaffeensis 1,475 Tularemia 180 Powassan virus 8

4 Reported cases of tickborne disease, United States, 2014 Disease Cases Lyme disease 33,461 Spotted fever rickettsiosis 3,647 Ana. phagocytophilum 2,800 Babesia 1,759 Ehrlichia chaffeensis 1,475 Tularemia 180 Powassan virus 8 Top notifiable diseases, United States, 2014 Disease Cases Chlamydia 1,441,789 Gonorrhea 350,062 Syphilis 63,450 Salmonellosis 51,455 HIV diagnoses 35,606 Lyme disease 33,461 Pertussis 32,971

5 Reported cases of tickborne disease, United States, 2014 Disease Cases Lyme disease 33,461 Spotted fever rickettsiosis 3,647 Ana. phagocytophilum 2,800 Babesia 1,759 Ehrlichia chaffeensis 1,475 Tularemia 180 Powassan virus 8 Top notifiable diseases, Northeast US, 2014 Disease Cases Chlamydia 227,609 Gonorrhea 47,391 Lyme disease 25,801 Syphilis 11,081 Salmonellosis 7,199 HIV diagnoses 6,202 Pertussis 3,422

6 Geographic distribution of key tickborne diseases

7 Reported cases Reported cases of tickborne disease by year United States, ,000 45,000 40,000 35,000 30,000 25,000 20,000 15,000 10,000 5, Babesia* Lyme Ehrlichiosis Anaplasmosis Rickettsioses

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12 Geographic expansion of Lyme disease risk United States, High-incidence counties identified for each of four 5-year time periods High-incidence defined as county in high-risk spatial cluster with county-specific RR >2.0 Method does not capture all counties with Lyme disease transmission Time period when county first reached high-incidence threshold: Kugeler et al. Emerg Infect Dis 2015;21:

13 Estimates of Lyme disease under-reporting State Year Underreporting Method CT X MD survey 1 MD X MD survey 2 NY X Tick bite model 3 WI X Record review 4 Refs: 1) Meek ) Coyle ) Campbell ) Nalaway 2002

14 Lyme disease testing by large commercial laboratories in the United States, 2008 Hinckley A, et al. CID 2014; 59: Survey of 7 large, national clinical diagnostic laboratories ~2,400,000 patient samples tested in 2008 Estimated cost of testing = $492,000,000 Corrected for test performance and clinical stage, true infection rate among samples ~ 12% Estimated 288,000 infected source patients (range 240, ,000)

15 Incidence of clinician diagnosed Lyme disease in the United States, Nelson C, et al. EID 2015; 9: Analysis of large medical claims database using diagnostic codes and prescription information insured persons <65 years old 103,647,966 person-years of observation 44,445 outpatient and 985 inpatient Lyme disease diagnoses identified Estimated 329,000 patients treated for Lyme disease annually (range 296, ,000)

16 Estimates of Lyme disease under-reporting State Year Underreporting Method CT X MD survey 1 MD X MD survey 2 NY X Tick bite model 3 WI X Record review 4 All 2008, X Lab survey, 5 claims data 6 Refs: 1) Meek ) Coyle ) Campbell ) Nalaway ) Hinckley ) Nelson 2015

17 Cost estimates for Lyme disease United States Author Period Mean cost per case Cost description Pauly et al $ 6,196 Total medical, non-medical, productivity losses Zhang et al $ 1,965 2 Total medical, non-medical, productivity losses Adrion et al $ 2,968 Excess medical costs 1 Unpublished report 2 Median cost = $281

18 Prevention Clin Infect Dis 2011;52:S271-5

19 Hayes and Piesman, N Engl J Med 2003;348: Avenues for prevention

20 Hayes and Piesman, N Engl J Med 2003;348: Avenues for prevention

21 Effectiveness of repellent for preventing Lyme disease Reference P value Effect* Variable 2008 Vázquez OR 0.8 Use on skin or clothing 1990 Schwartz 0.05 OR 0.5 Use of repellent 2001 Smith G OR 0.7 Use away from home 2001 Smith G 1 NS OR 1.2 Use in yard 2009 Connally 1 NS OR 0.6 Wore in yard 2001 Phillips 2 NS - Usually or always use 1998 Orloski 1 NS OR 1.0 Use of repellent 1996 Klein 1 NS - Use of repellent 1995 Ley 1 NS OR 1.5 Use in past month 1998 Smith P 2,3 NS RR 0.5 On skin at work 1998 Smith P 2,3 NS RR 0.7 On skin at leisure * OR = Odds Ratio, RR Relative Risk 1 case control, 2 cross-sectional, 3 odds ratios presented as inverse

22 Effectiveness of tick checks for preventing Lyme disease Reference P value Effect* Variable 2009 Connally OR 0.5 within 36 hrs of exp Connally OR 0.4 Bath within 2 hrs of exp Smith G OR 0.6 Check during activities 2001 Smith G 1 NS OR 1.2 after activities 2008 Vázquez 1 NS OR 1.0 Check body after exposure 2001 Phillips 2 NS - Usually or always check 1998 Orloski 1 NS OR 0.5 Performed tick check 1996 Klein 1 NS - Use of tick checks 1995 Ley 1 NS OR 0.8 Always vs. never checking 1988 Smith P 2,3 NS RR 1.1 Check for ticks at work 1988 Smith P 2,3 NS RR 0.8 Check for ticks at leisure * OR = Odds Ratio, RR Relative Risk 1 case control, 2 cross-sectional, 3 odds ratios presented as inverse

23 Personal protective measures Inexpensive and unlikely to be harmful Insect repellent Tick checks Protective clothing Showering promptly after exposure Insufficient at population level

24 Hayes and Piesman, N Engl J Med 2003;348: Avenues for prevention

25 Effectiveness of residential acaricides to prevent Lyme and other tickborne diseases in humans Randomized, double-blinded, placebo-controlled trial of single springtime pesticide application bifenthrin vs. water barrier spray Hinckley A, et al. JID 2016; e -pub 2,727 households in 3 northeastern states Questing ticks >60% lower on acaricide-treated properties No comparable reduction in human exposure to ticks or tickborne illness

26 Conclusions Tickborne diseases continue to emerge as an important public health problem in the United States Disease burden substantial Case counts increasing Geographic expansion Existing prevention methods inadequate

27 Acknowledgments State & Local Health Departments TickNet Emerging Infections Program Partners For more information, contact CDC CDC-INFO ( ) TTY: Alison Hinckley, Sarah Hook, Kiersten Kugeler, Christina Nelson, Anna Perea, Amy Schwartz, Ryan Max, Ben Beard The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention.