TY - JOUR AU - Wahnich, Amanda AU - Lall, Ramona AU - Weiss, Don PY - 2017/05/02 Y2 - 2024/03/28 TI - Monitoring for Local Transmission of Zika Virus using Emergency Department Data JF - Online Journal of Public Health Informatics JA - OJPHI VL - 9 IS - 1 SE - Communicable Disease Surveillance Use Cases for Human, Animal, and Zoonotic Diseases DO - 10.5210/ojphi.v9i1.7698 UR - https://ojphi.org/ojs/index.php/ojphi/article/view/7698 SP - AB - <div style="left: 78.2727px; top: 278.962px; font-size: 12.3207px; font-family: sans-serif; transform: scaleX(1.0823);" data-canvas-width="55.467823232323234">Objective</div><div style="left: 91.3182px; top: 291.965px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.990406);" data-canvas-width="330.861499747475">Case and cluster identification of emergency department visits</div><div style="left: 78.2727px; top: 306.46px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.00138);" data-canvas-width="208.40476010101014">related to local transmission of Zika virus.</div><div style="left: 78.2727px; top: 334.043px; font-size: 12.3207px; font-family: sans-serif; transform: scaleX(1.11884);" data-canvas-width="71.86668434343434">Introduction</div><div style="left: 91.3182px; top: 347.046px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.965141);" data-canvas-width="330.5768914141413">The first travel-associated cases of Zika virus infection in New</div><div style="left: 78.2727px; top: 361.541px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.986522);" data-canvas-width="341.66552777777764">York City (NYC) were identified in January 2016. Local transmission</div><div style="left: 78.2727px; top: 376.036px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.969598);" data-canvas-width="344.0619053030301">of Zika virus from imported cases is possible due to presence of</div><div style="left: 78.2727px; top: 390.531px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.976799);" data-canvas-width="343.80070631313134">Aedes albopictus mosquitos. Timely detection of local Zika virus</div><div style="left: 78.2727px; top: 405.026px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.03794);" data-canvas-width="343.3510005050505">transmission could inform public health interventions and mitigate</div><div style="left: 78.2727px; top: 419.521px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.02062);" data-canvas-width="342.97768308080805">additional spread of illness. Daily emergency department (ED) visit</div><div style="left: 78.2727px; top: 434.016px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.991533);" data-canvas-width="341.89715707070707">surveillance to detect individual cases and spatio-temporal clusters of</div><div style="left: 78.2727px; top: 448.511px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.00135);" data-canvas-width="306.9457752525251">locally-acquired Zika virus disease was initiated in June 2016.</div><div style="left: 78.2727px; top: 476.094px; font-size: 12.3207px; font-family: sans-serif; transform: scaleX(1.07424);" data-canvas-width="50.65042676767676">Methods</div><div style="left: 91.3182px; top: 489.097px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.01295);" data-canvas-width="331.7227171717172">ED visits were classified into two Zika syndromes based on</div><div style="left: 78.2727px; top: 503.592px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.02077);" data-canvas-width="342.9111512626263">chief complaint text and the International Classification of Diseases</div><div style="left: 78.2727px; top: 518.086px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.0272);" data-canvas-width="230.29865656565653">version 9 and 10 diagnosis codes for patients</div><div style="left: 308.569px; top: 520.427px; font-size: 12.3207px; font-family: sans-serif;">≥</div><div style="left: 315.331px; top: 518.086px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.03653);" data-canvas-width="105.93343939393941">6 years old: 1) fever</div><div style="left: 78.2727px; top: 532.581px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.03438);" data-canvas-width="342.89759848484863">and 2) Zika-like illness. Zika-like illness was defined as visits with</div><div style="left: 78.2727px; top: 547.076px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.946606);" data-canvas-width="343.17604646464656">mention of Zika; symptoms of rash, fever, and either joint pain or</div><div style="left: 78.2727px; top: 561.571px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.999339);" data-canvas-width="342.19038989898996">conjunctivitis; diagnosis of Guillain-Barré syndrome; or diagnosis of</div><div style="left: 78.2727px; top: 576.066px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.00127);" data-canvas-width="204.9426414141415">rare and non-endemic arboviral infection.</div><div style="left: 91.3182px; top: 590.561px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.01449);" data-canvas-width="322.4550813131313">We applied the prospective space-time permutation scan statistic</div><div style="left: 413.758px; top: 590.887px; font-size: 7.39242px; font-family: serif;">1</div><div style="left: 78.2727px; top: 605.056px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.955672);" data-canvas-width="343.3411439393941">in SaTScan daily since June 2016 to the fever syndrome, selected</div><div style="left: 78.2727px; top: 619.551px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.02398);" data-canvas-width="342.94688131313114">as a single representative symptom, to detect clusters by hospital or</div><div style="left: 78.2727px; top: 634.046px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.952242);" data-canvas-width="343.41013989898966">zip code of patient residence. The maximum spatial cluster size is</div><div style="left: 78.2727px; top: 648.541px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.00041);" data-canvas-width="342.24090479797985">20% of observed visits, and the maximum temporal cluster size is 14</div><div style="left: 78.2727px; top: 663.036px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.00605);" data-canvas-width="193.21209621212117">days – reflecting the incubation period.</div><div style="left: 271.467px; top: 663.362px; font-size: 7.39242px; font-family: serif;">2</div><div style="left: 275.163px; top: 663.036px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.00355);" data-canvas-width="145.4311621212121">The study period is 90 days.</div><div style="left: 78.2727px; top: 677.531px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.01286);" data-canvas-width="342.68445025252515">Statistical significance is determined using Monte Carlo simulations</div><div style="left: 78.2727px; top: 692.026px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.03538);" data-canvas-width="268.7146212121212">(N=999). Any cluster with a recurrence interval</div><div style="left: 347.111px; top: 694.366px; font-size: 12.3207px; font-family: sans-serif;">≥</div><div style="left: 354.099px; top: 692.026px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.02608);" data-canvas-width="69.46537853535354">365 days is</div><div style="left: 78.2727px; top: 706.521px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.956015);" data-canvas-width="343.4643510101012">summarized in a map and line-list of contributing visits. The map</div><div style="left: 78.2727px; top: 721.016px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.99711);" data-canvas-width="342.1583560606059">depicts the zip codes of the cluster with an overlay of census tracts at</div><div style="left: 78.2727px; top: 735.511px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.03391);" data-canvas-width="343.1045863636365">highest risk for human importation of Zika virus, as estimated by a</div><div style="left: 78.2727px; top: 750.006px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.01278);" data-canvas-width="342.6585767676767">zero-inflated Poisson regression model developed at NYC DOHMH</div><div style="left: 78.2727px; top: 764.501px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.02821);" data-canvas-width="342.97645101010096">that is updated regularly to reflect the most recent available data on</div><div style="left: 78.2727px; top: 778.996px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.0097);" data-canvas-width="82.7951515151515">confirmed cases.</div><div style="left: 91.3182px; top: 793.491px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.974126);" data-canvas-width="330.65081565656556">Zika-like illness syndrome visits are output in a daily line-list.</div><div style="left: 78.2727px; top: 807.985px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.983573);" data-canvas-width="344.08654671717176">DOHMH staff contact the EDs that patients visited to determine</div><div style="left: 78.2727px; top: 822.48px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.02794);" data-canvas-width="342.8507797979797">travel to Zika-affected country, clinical suspicion of Zika infection,</div><div style="left: 78.2727px; top: 836.975px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.00147);" data-canvas-width="110.52906313131315">and laboratory testing.</div><div style="left: 78.2727px; top: 864.558px; font-size: 12.3207px; font-family: sans-serif; transform: scaleX(1.08542);" data-canvas-width="44.50239393939395">Results</div><div style="left: 91.3182px; top: 877.561px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.98655);" data-canvas-width="331.16828535353534">During June 1–August 16, 2016, we observed a mean of 253</div><div style="left: 78.2727px; top: 892.056px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.03346);" data-canvas-width="343.17851060606046">(range: 202-299) ED visits for the fever syndrome per day. Sixteen</div><div style="left: 78.2727px; top: 906.551px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.981823);" data-canvas-width="341.88730050505023">spatio-temporal fever syndrome clusters have been detected. Of these,</div><div style="left: 78.2727px; top: 921.046px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.0319);" data-canvas-width="343.1230674242424">2 clusters were during testing and optimization of scan parameters,</div><div style="left: 78.2727px; top: 935.541px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.0468);" data-canvas-width="343.1045863636365">13 were due to data quality issues, and 1 was dismissed due to the</div><div style="left: 78.2727px; top: 950.036px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.00376);" data-canvas-width="292.21020959595955">large geographic range of the cluster, spanning 3 boroughs.</div><div style="left: 91.3182px; top: 964.531px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.997118);" data-canvas-width="331.6414005050503">During June 1–August 16, 2016, we observed a mean of 2.7</div><div style="left: 78.2727px; top: 979.026px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.980632);" data-canvas-width="341.83185732323227">(range: 0-7) ED visits for the Zika-like illness syndrome. Daily counts</div><div style="left: 78.2727px; top: 993.521px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.0092);" data-canvas-width="342.5070320707071">ranged from 0-3 visits from June 1-June 16 and 1-7 visits since June</div><div style="left: 78.2727px; top: 1008.02px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.00378);" data-canvas-width="342.3554873737373">16. Nineteen visits that occurred from July 31-August 4 were further</div><div style="left: 78.2727px; top: 1022.51px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.04228);" data-canvas-width="343.3608570707069">investigated to establish a protocol for follow-up. Of those, eleven</div><div style="left: 78.2727px; top: 1037.01px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.03665);" data-canvas-width="342.9222398989899">patients reported recent travel to countries with local transmission,</div><div style="left: 78.2727px; top: 1051.5px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.01017);" data-canvas-width="342.4811585858584">one had travel over 3 months ago and an alternate diagnosis, six had</div><div style="left: 443.545px; top: 277.47px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.97955);" data-canvas-width="341.7813424242424">unknown travel history due to incomplete follow-up, and one reported</div><div style="left: 443.545px; top: 291.965px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.0393);" data-canvas-width="343.1070505050505">no travel. The one without travel had a diagnosis inconsistent with</div><div style="left: 443.545px; top: 306.46px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.992905);" data-canvas-width="341.90701363636356">Zika virus disease. Subsequently, analysts contacted EDs only for the</div><div style="left: 443.545px; top: 320.955px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.98378);" data-canvas-width="341.9291909090908">subset of Zika-like illness syndrome visits with no indication of travel</div><div style="left: 443.545px; top: 335.45px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.00401);" data-canvas-width="342.3345421717172">or without an alternate discharge diagnosis. Findings from this effort</div><div style="left: 443.545px; top: 349.945px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.0014);" data-canvas-width="87.25524747474746">will be presented.</div><div style="left: 443.545px; top: 377.528px; font-size: 12.3207px; font-family: sans-serif; transform: scaleX(1.10408);" data-canvas-width="73.93656313131314">Conclusions</div><div style="left: 456.591px; top: 390.531px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.986606);" data-canvas-width="328.75342676767656">The fever syndrome provides a means to monitor for clusters using</div><div style="left: 443.545px; top: 405.026px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.984578);" data-canvas-width="341.84541010101003">ED data. Prospective cluster detection signal volume was manageable</div><div style="left: 443.545px; top: 419.521px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.999325);" data-canvas-width="343.9510189393939">and has not identified clusters requiring additional investigation.</div><div style="left: 443.545px; top: 434.016px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.04553);" data-canvas-width="345.5982974747473">The Zika-like illness syndrome can be used for case finding.</div><div style="left: 443.545px; top: 448.511px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.00162);" data-canvas-width="344.42290202020223">Contacting EDs helps to supplement information missing in the</div><div style="left: 443.545px; top: 463.006px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.02046);" data-canvas-width="342.82367424242415">syndromic system, such as travel history as well as Zika testing and</div><div style="left: 443.545px; top: 477.501px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.01398);" data-canvas-width="342.7078595959595">diagnosis. As Zika-like illness syndrome counts are low and disease</div><div style="left: 443.545px; top: 491.996px; font-size: 12.3207px; font-family: serif; transform: scaleX(0.994574);" data-canvas-width="342.0671828282829">is emergent, contacting EDs is feasible and helpful in ruling out local</div><div style="left: 443.545px; top: 506.491px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.02468);" data-canvas-width="342.82367424242426">Zika virus transmission. No visits or clusters to-date have indicated</div><div style="left: 443.545px; top: 520.985px; font-size: 12.3207px; font-family: serif; transform: scaleX(1.00168);" data-canvas-width="92.40530303030305">local transmission.</div> ER -