Dallas County Health and Human Services Arbovirus Surveillance Report Week 39 ending September 29, 2018

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1 Dallas County Health and Human Services Arbovirus Surveillance Report Week 39 ending September 29, 18 In week 38, ten mosquito traps tested positive for WNV in Culex quinquefasciatus. In week 39 to date, eight mosquito traps tested positive for WNV in Culex quinquefasciatus. Positive traps were located in the following zip codes: 754, 7588, 75149, 75181, 755, 75216, and To date, eleven human WNV cases were reported in 18. One WNV associated death was reported in 18. In 18, no travel-associated confirmed human Zika cases have been identified in Dallas County. Five pregnant women with laboratory criteria for possible Zika infection have been reported to CDC for inclusion in the US Zika Pregnancy Registry. Aedes albopictus and Aedes aegypti are currently circulating in the area. Table 1. Mosquito Laboratory and Human Case Surveillance Data for WNV in Cx. quinquefasciatus, Dallas County Week Ending 8/18 8/25 9/1 9/8 9/15 9/22 9/29 YTD MMWR Week * 39* Total Placed in Dallas County a ,23 Number of Positive Mosquito (PHL; IL) b,c 21; 11; 15; 1 16; 12; 1 9; 1 8; 173; 7 Number of Pools Tested (PHL; IL) b,c 215; ; ; ; 34 ; ; ; 27 4,49; 613 Number of Trap Results Currently Pending Average Number of Cx. quinquefasciatus per Trap d Total Number of Cx. quinquefasciatus Trapped and Tested 6,728 5,529 7,947 7,321 5,25 7,82 5, ,279 Number of Positive Mosquito Pools (PHL; IL) c 21; 11; 17; 1 16; 12; 1 9; 1 8; 179; 8 WNV Infection Rate per 1, Cx. quinquefasciatus e Weekly Vector Index (VI) f Presumptive WNV Viremic Blood Donors WNV Human Cases (WNND; WNF) g 1; ; 1 2; 1; ; 1; ; 1 9; 2 Table 2. Mosquito Laboratory and Human Case Surveillance Data for Chikungunya, Dengue and Zika Virus, Dallas County Week Ending 8/18 8/25 9/1 9/8 9/15 9/22 9/29 YTD MMWR Week * 39* Total Biogents Sentinel- Placed in Dallas County h Average Number of Aedes per Trap i Chikungunya Human Cases (Confirmed & Probable) j Dengue Human Cases (Confirmed & Probable) k 1 1 Zika Human Cases (Confirmed & Probable) l Pregnant Women with Possible Zika Infection m *Data for most recent 2 weeks are preliminary, and reflect results reported as of 12:3 p.m. October 1, 18. a. All traps deployed in municipalities submitting data to DCHHS since January 1, 18. Includes traps without mosquitoes, malfunctioning traps and traps with pending results b. Excludes traps without female Culex quinquefasciatus identified. Maximum of 5 female Culex quinquefasciatus per pool; more than 1 pool may be tested per trap c. PHL = Public health laboratory (DSHS, DCHHS) testing performed by viral culture or CDC RT-PCR protocol; IL = Testing from independent labs by alternate methods d. Average abundance of female Culex quinquefasciatus mosquitoes per trap night/week (excludes non-working traps) e. WNV Infection rates calculated using a Maximum Likelihood Estimation (MLE). Biggerstaff BJ. PooledInfRate, version 4.; Microsoft Excel Add-In; CDC 7 f. The Vector Index (VI) reflects the MLE adjusted for Culex quinquefasciatus abundance. VI=, where N is the average number of Culex quinquefasciatus mosquitoes collected per trap night and is the estimated infection rate g. Human cases by week of report to health department. WNND = West Nile Neuroinvasive Disease; WNF = West Nile Fever h. All Biogents (BG) Sentinel traps deployed in municipalities submitting data to DCHHS since Week 13. i. Average abundance of Aedes albopictus and Aedes aegypti mosquitoes per night/trap in BG- (excludes non-working traps) j. Human CHKV cases by week of report to health department (AT : Autochthonous case; I : imported) k. Human Dengue cases by week of report to the health department l. Confirmed and probable human Zika cases by week of specimen collection date m. Possible Zika Virus Infection Among Pregnant Women United States and Territories, May 16,

2 Table 3. WNV Positive Gravid Mosquito and Human WNV Cases by City, Dallas County, 18 Week Ending 8/18 8/25 9/1 9/8 9/15 9/22 9/29 YTD MMWR Week * 39* # Human Cases Range Total # of /Week 1 Addison 2 1 Balch Springs Carrollton 7 1 Cedar Hill Cockrell Hill 1 Coppell Dallas DeSoto Duncanville Farmers Branch Garland Glenn Heights Grand Prairie Highland Park Hutchins 1 3 Irving Lancaster 4 5 Mesquite Richardson Rowlett Sachse Seagoville Sunnyvale 2 Unincorporated County 1 4 University Park Wilmer 1 Total *Data for most recent 2 weeks are preliminary, and reflect results reported as of 12:3 p.m. October 1, Range of numbers of traps placed weekly, in weeks Figure 1: All WNV Negative and Positive Mosquito Collected During 18: Weeks 1-39* (N=6,23) Figure 2: Cumulative WNV Positive Mosquito Collected During 18: Weeks 1-39* (N=18) Positive Negative Pending DCHHS Epidemiology (214) Epidemiology@dallascounty.org *Data for most recent 2 weeks are preliminary

3 Average Abundance Cx. quinquefasciatus Figure 3: WNV Positive Mosquito Collected During 18: Weeks 38 and 39* (N=18) Figure 4: Trap Counts of Female Cx. quinquefasciatus from 18 Season: Weeks 1-39* Positive < 1 Mosquitoes/Trap Mosquitoes/Trap 5-1 Mosquitoes/Trap >1 Mosquitoes/Trap *Figure 4 only shows traps for which results were available; malfunctioning traps were excluded. Almost all traps are at fixed sites. Note: Most recent 1-2 weeks data are preliminary and subject to change following receipt of data still pending. Figure 5: Average Numbers of Female Cx. quinquefasciatus per Trap-night and WNV Vector Index by Week: 12 Season and 18 Season (through Week 39*) 8 7 Average Abundance 18 Average Abundance VI 12 VI **.4 Vector Index Collection Date by MMWR Week ** Vector Index of.5 is the historical threshold associated with larger local epidemics of WNV illnesses in humans. Note: Most recent 1-2 weeks data are preliminary and subject to change following receipt of data still pending.. DCHHS Epidemiology (214) Epidemiology@dallascounty.org

4 MLE (WNV Infection Rate per 1, Cx. quinquefasciatus) Average Abundance Cx. quinquefasciatus Vector Index (VI) Figure 6: WNV Vector Index by Week: Seasons The Vector Index (VI) reflects the MLE adjusted for Culex quinquefasciatus abundance. VI=, where N is the average number of Culex quinquefasciatus mosquitoes collected per trap night and is the estimated infection rate MMWR Week- Year Figure 7: Average Numbers of Female Cx. quinquefasciatus per Trap-night by Week: Seasons MMWR Week - Year 6 Figure 8: MLE (WNV Infection Rate per 1, Cx. quinquefasciatus) by Week: Seasons MMWR Week - Year DCHHS Epidemiology (214) Epidemiology@dallascounty.org

5 Average Abundance of Aedes aegypti Average Abundance of Aedes albopictus Figure 9: BG-Sentinel Trap Counts of Female Aedes aegypti and Aedes albopictus During 18: Weeks 13 through 39 Mosquitoes/Trap <1 Mosquitoes/Trap 1-3 Mosquitoes/Trap >3 Mosquitoes/Trap Figure 1: Average Numbers of Aedes aegypti per Trap-night: 17 and 18 Seasons*, Figure 11: Average Numbers of Aedes albopictus per Trap-night: 17 and 18 Seasons*, * April June Aug Oct Collection Date by MMWR Week April June Aug Oct Collection Date by MMWR Week *Data for most recent 2 weeks are preliminary Routine Aedes BG-Sentinel trapping was conducted during week in 17 DCHHS Epidemiology (214) Epidemiology@dallascounty.org

6 1/1/18 1/8/18 1/15/18 1/22/18 1/29/18 2/5/18 2/12/18 2/19/18 2/26/18 3/5/18 3/12/18 3/19/18 3/26/18 4/2/18 4/9/18 4/16/18 4/23/18 4/3/18 5/7/18 5/14/18 5/21/18 5/28/18 6/4/18 6/11/18 6/18/18 6/25/18 7/2/18 7/9/18 7/16/18 7/23/18 7/3/18 8/6/18 8/13/18 8//18 8/27/18 9/3/18 9/1/18 9/17/18 9/24/18 Number of Rash Reports Figure 12: Syndromic Surveillance of Emergency Department Visits for Chief Complaints of Rash, Dallas County: January 1, 18 September 29, Data alert Data warning Data normal Data source: 18 emergency departments in Dallas County hospitals participating in the Electronic Surveillance System for the Early Notification Of Community-based Epidemics (ESSENCE) voluntarily reporting the numbers of persons presenting with self-reported chief complaints of rash. Acknowledgements: We are grateful for the partnership of the following contributors to our county-wide Arboviral Surveillance Report: Mosquito Trapping and Data from Environmental Health Services Divisions of the Following Cities: Addison Balch Springs Carrollton Cedar Hill Cockrell Hill Coppell Dallas DeSoto Duncanville Farmers Branch Garland Glenn Heights Grand Prairie Mosquito Trapping and Data From: Highland Park Hutchins Irving Lancaster Mesquite Richardson Rowlett Sachse Seagoville Sunnyvale University Park Wilmer DCHHS Environmental Health Services: Vector Control Division Municipal Mosquito Vector Disease Control International Mosquito Speciation and Laboratory Testing: DCHHS Environmental Health Services: Mosquito Lab DCHHS LRN Laboratory DSHS Laboratory Services, Arbovirus-Entomology Team Municipal Mosquito Human Case Reports and Investigations: Area Acute Care Hospitals and Healthcare Providers Dallas County Medical Examiner s Office City of Dallas Vital Statistics Unit Carter Blood Care American Red Cross DCHHS Acute Communicable Disease Epidemiology Division Zika Pregnancy Registry Team Arboviral Case Investigation and Clinical Inquiries Team For inquiries related to this Arboviral Surveillance Report, please contact: James Blackwell, MPH DCHHS Epidemiology (214) Epidemiology@dallascounty.org