Bugs are Bringing Bugs Mosquito and Tick-borne Diseases

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Regina Wood
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1 Bugs are Bringing Bugs Mosquito and Tick-borne Diseases Greenville Postgraduate Seminar April 11, 2014 Eric Brenner, MD

2 Type of Pathogen Examples of Vector-borne Diseases (*) Vector Mosquito Tick Louse Flea Fly Virus Arboviruses WNV Yellow Fever Dengue EEE WEE SLE LACV Chikungunya Powassan (POW) TBE (Tick borne encephalitis) Bacteria Lyme Disease RMSF Anaplasmosis Ehrlichiosis TBRF Tularemia Typhus LBRF Plague Trachoma Tularemia Protozoa Malaria Babesiosis Leishmaniasis Metazoa Dog heartworm Onchocerciasis (*) Examples only, thus not a complete list

3 Hence, in SC had fatal bubonic, septicemic and pneumonic plague acquired not abroad, but in New Mexico!

4 Another SC Case Presentation 36 yo male c/o fever x 4 days with chills, headache and general malaise. No special cyclical fever pattern noted. Pt. had just returned from overseas tour as a Peace Corps Volunteer Had been working in Malawi (East Africa) for 9 months. PMH: no significant past or present co-morbidities Medications: Had been taking weekly mefloquine for antimalarial prophylaxis x 8 months. DC ed meds just in last few weeks prior to departure home. Other travel history: Thailand, Malaysia, Honduras, Nicaragua within the last 6-7 years.

5 Physical Exam Healthy-looking patient, afebrile Ox3. No nucal rigidity or neuro deficits No pallor No organomegaly No petechiae or muco-cutaneous stigmata of endocarditis or HIV

6 What is the Presumptive / Working Diagnosis?

7 Medical Decision Priorities Malaria until proven otherwise How to confirm diagnosis Blood smear (traditional!) Rapid blood tests (newer but are they available?) What species? Parasitemia level? Cerebral malaria? Other complications? Labs to check for complications (Hb, glucose, creatinine, LFTs ) IV vs. po treatment Is hospitalization required?

8 Ring-form trophozoites Banana-shaped gametocytes Morphology confirms infection due to Plasmodium falciparum

9 What does one need to know about malaria Rx? 1. On the tropical medicine board exam? Nuances, doses, options for routes of administration of all the antimalarials as might be used singly or in combination 2. In every day front-line primary care practice? CDC clinicians on-call 24/7 to provide advice to clinicians re malaria Dx/Rx. Malaria Hotline (or toll free ) M-F 9-5. Off-hours, weekends, and holidays => and ask for malaria clinician on-call. Or more simply: Daytime main CDC Number: Nights/weekends:

10 Malaria Perspectives Malaria (and YF) common in SC in colonial days Endemic local transmission now eliminated, though the insect vectors remain (Anopheles for malaria; Aedes for YF) Cases now thus seen only in: 1. Internationals arriving from endemic countries 2. Americans who have travelled to malarious areas and fail to take proper anti-malarials 3. VFRs ( Visiting Friends and Relatives ): i.e. Internationals going home on vacation who do not take prophylaxis and who for several reasons -- are at high risk of disease!

11 Year SC VBDs in Perspective ( ) RMSF Tick-borne Lyme Disease Babesiosis Malaria Dengue Mosquito-borne WN Fever WNV - Neuroinvasive Total EEE

12 Why is this a good time to think about vector-borne diseases? Just getting into lovely spring & summer weather Outdoor activities Summer holidays Hikes and woods Mosquito & tick season! April 7: WHO s World Health Day this year focuses on vector-borne diseases under the theme: Small bite, big threat Theme echoed world-wide e.g. at PAHO, CDC etc.

13 (

14 WHO World Health Day 2014 Posters re Vector-borne Diseases

15 CDC world Health Day Flyer

22 Reported Lyme Disease Cases 2012 (CDC) We have Ixodes scapularis ticks in Connecticut AND in South Carolina. So, why the difference in incidence in Lyme Disease???

23 Southern Tick-Associated Rash Illness (STARI)

24 Reported Cases of Rocky Mountain Spotted Fever (RMSF) 2012

25 Ehrlichia Chaffeensis- 2012

26 Anaplasma phagocytophilium-2012

27 Distribution of Key Tickborne Diseases, 2012 (CDC)

29 Lyme Disease Caused by spirochete Borrelia burgdorferi Caused by Ixodes ticks ~30,000 cases reported annually in US Studies about to appear suggest actual number of annual infections may be closer to ~300,000 (!!) BUT this jump largely indicative of underreporting and NOT of increase Main geographic foci not greatly changing (though there has been a gradual southward extension from previous mainly New England hyper-endemic focus This revised estimate based on surveys of medical visit coding, laboratory test results and other indirect counting & extrapolation methods

30 Life Cycle of Ixodes Scapularis (CDC)

31 Primary Dis. Transmitted Lyme disease Anaplasmosis Babesiosis Powassan disease STARI Ehrlichiosis Tularemia RMSF

33 Erythema Migrans (EM) Seen in ~ 70-80% of cases ~1-2 weeks after tick bite Expands over days Rarely painful Distinguish from allergic reaction?

34 Atypical EM Presentations

Arthritis Intermittent Oligoarticular Swelling >>

35 Disseminated and Late Lyme Disease Facial Palsy Summer months May be bilateral +/- CSF pleocytosis Arthritis Intermittent Oligoarticular Swelling >> pain Late-stage neurologic Peripheral neuropathy Encephelopathy

37 (MMWR Dec 13, 2013)

38 (MMWR Aug 16, 2013)

39 Comparison: In one case deaths from cardiac complications of unrecognized tick-bites whereas here we have rabies death following an unrecognized bat bite (JSCMA June 2013)

42 Sensitivity of Two-Tiered Serologic testing (*) Lyme Diseae Stage Sensitivity (%) EM rash (acute) 38 EM rash (convalescent) 67 Early Neurologic 87 Late Neurologic 100 Arthritis 97 (*) Specificity of two-tiered testing generally >95 Bottom Line: Two-tiered testing performs well in late stages of disease Testing of EM patients not generally necessary (?!)

44 Possible red flags for alternate labs (CDC) Tests offered are not FDA approved Laboratory claims to specialize in Lyme and other tick-bone disease testing Do not accept insurance => patient pays out of pocket (e.g. $500 - $ )

55 The Nile Uganda: West Nile District River Basin

56 NY Times Sept 4, 1999

57 NY Times Sept 8, 1999

58 NY Times Sept 25, 1999

59 Unusual Encephalitis Cluster in Northern Queens, 1999

61 NYT April 8, 2013 What does this story about a single (just 1!) case of polio in Baghdad have to do with WNV?

62 Household-based Serosurvey Conducted in 2x2 Mile area in Northern Queens in Persons 5+ y.o. 44% Participation among households selected by cluster sampling Estimated seroprevalence : 2.6% (95% CI: %) 20% of seropositive individuals reported febrile illness. Primary symptoms included: - Myalgias (100%) - Fatigue (87%) - Headache (89%) - Arthralgias (76%) Overall neuroinvasive infection to asymptomatic infection ratio ~ 1:

63 A natural history pyramid with essentially the same shape and compartment proportions as we find in polio (!!) with similar consequences about how we may consider what is really happening when we have even one person with polio paralysis or WNV neuro-invasive disease.

64 Potential Sources of Introduction of WNV into NYC (?) Migrating viremic bird? Imported viremic bird (legally or illegally)? Viremic human traveler? Imported mosquitoes (airplane or ship)? Intentional release?

65 West Nile Outbreak 1999:Lessons Learned / Conclusions Need to always remain open-minded to the possibility of the unexpected Importance of strong relationships between the medical community and public health. Need to engage nontraditional public health partners (e.g., veterinarians, wildlife experts) Unusual events in animals/birds may be an early warning for human disease outbreaks Newly introduced West Nile virus may become endemic in the US

72 Countries with reported local transmission of Chikungunya virus (as of )

75 Chickungunya Virus - 1 Single stranded RNA virus Related to Mayaro, O nyong-nyong and Ross River viruses Predominantly spread by Aedes aegypti and Aedes albopictus (same vectors as for Dengue!) Aggressive daytime biters Most (~72-97%) infected develop symptoms: typically abrupt fever >39.0C + often severe polyarthralgia Also variable: headache, myalgia, conjunctivitis, NV, maculopapular rash Risk factors for hospitalization or atypical disease: neonates, older age, underlying conditions

76 Chickungunya Virus - 2 Dx assays (e.g. through DHEC and CDC) Viral culture (<= 3days) RT-PCR <=8days) IgM Ab >= 4 days Treatment No specific antiviral Supportive care / rest /fluids / NSAIDS

77 Some Final Thoughts and Questions? Will range of Chickungunya transmission extend up from Caribbean to Florida (where Dengue is already established, and thence (also with Dengue) up the SE Coast where Aedes mosquitoes are already present! Might these new virus go coast to coast in a few years. Just as did WNV? Will society be willing to invest in government run community-wide mosquito control programs -- or leave backyard spraying to the private sector? What consequences of emerging VBDs for front-line medical practice? Will global warming extend the eco-range of various mosquito (and other) vectors, and hence radically change the epidemiology and distribution of VBDs!?

Outbreak Investigation Guidance for Vectorborne Diseases

COMMUNICABLE DISEASE OUTBREAK MANUAL New Jersey s Public Health Response APPENDIX T3: EXTENDED GUIDANCE Outbreak Investigation Guidance for Vectorborne Diseases As per N.J.A.C. 8:57, viruses that are transmitted