Aedes aegypti surveillance and control in an epicenter of dengue virus transmission Roberto Barrera, Manuel Amador, Veronica Acevedo, Gilberto Felix, Ryan Hemme Entomology and Ecology Activity Dengue Branch, CDC Puerto Rico

Objective Use of the CDC Autocidal Gravid Ovitrap (AGO trap) for the surveillance and area-wide control of Ae. aegypti in Puerto Rico for the last three years

Autocidal, sticky gravid ovitrap (AGO; CDC patent EIR I ) Features: – 5-Gal plastic trap – Highly attractive / sensitive to Ae. aegypti gravid females – Can be deployed in the field for 2 months without maintenance or servicing – Does not use insecticides – Relatively inexpensive – Small sample size for reliable observations ( traps) – Has higher sensitivity than ovitraps – Correlated with BG trap captures without lure * Mackay AJ, Barrera R, Amador M An autocidal gravid ovitrap for the control and surveillance of Aedes aegypti. Parasites and Vectors 6:225

Setting the AGO trap Inspecting the AGO trap

AGO traps as surveillance tools

AGO traps as surveillance tools: Positive relationship between AGO and Ovitraps

AGO traps as surveillance tools: Positive, significant relationship between AGO and BG trap captures (Oct – Oct. 2012)

AGO traps as control tools Autocidal

We tested the effectiveness of the AGO traps (3 traps/home; 81% of homes) to control Ae. aegypti in one isolated urban area (intervention area) and compared it with another urban area (reference area) in southern Puerto Rico for one year (Phase I; Oct – Oct. 2012) We used BG-Sentinel and AGO traps (2.5 traps/Ha) to monitor the density of female Ae. aegypti every week Barrera et al. 2014a. Use of the CDC Autocidal Gravid Ovitrap to control and prevent outbreaks of Aedes aegypti (Diptera: Culicidae). J. Med. Entomol. 51(1): ; DOI: La Margarita (Intervention area; 327 bldgs.) Villodas (Reference area; 241 bldgs.) Aedes aegypti control

Results from the first year (Oct 2011 – Oct 2012) Female Ae. aegypti in AGO (top) or BG-traps (bottom) Lines = mosquitoes per trap per week Bars = Rainfall There was % reduction in female Ae. aegypti in the intervention area; most notably during the rainy season

Years two - three Intended to further demonstrate the effectiveness of the traps by placing AGO control traps in the community that formerly served as non-intervention or reference, expecting that Ae. aegypti density would converge to the low values observed in the intervention community We also added two new, nearby reference communities without control traps for comparison purposes Barrera R, Amador M, Acevedo V, Hemme, RR, Félix G. 2014b. Sustained, area-wide control of Aedes aegypti using CDC Autocidal Gravid Ovitraps. Am. J. Trop. Med. Hyg., 00(0), 2014, pp. 000–000. doi: /ajtmh

Study areas (Southern Puerto Rico, 4 communities) Arboleda New reference community January 2013 – to date Playa New reference community January 2013 – to date La Margarita Initial intervention community December 2011 – to date Villodas Second intervention community February 2013 – to date Former reference community December 2011 –January 2013

La Margarita (Intervention I; 327 bldgs.) Villodas (Intervention II; 241 bldgs.) Playa (Reference I) Arboleda (Reference II)

Results – control traps added to former reference area Shows convergence to low, steady population

Results – Ae. aegypti density in urban sites without and with AGO control traps Ae. aegypti density is 7-13 times higher in untreated sites 3 AGO traps / home No AGO control traps

Conclusions 3 AGO traps in 85% of the households controlled Ae. aegypti populations in 60-80% What traps do is eliminate gravid females and reduce # eggs per container (sink effect) Mosquito outbreaks followed rainfall in non- intervention areas – no mosquito outbreaks were observed in intervention areas Are these observed reductions enough to prevent dengue virus / chickungunya transmission? Under investigation Need to understand better the dynamics of Ae. aegypti at low population densities

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