Ernst Kacey

West Nile Virus (WNV) and dengue virus (DENV) are both arboviruses which are transmitted to humans by an infected mosquito bite during blood-meal feeding. The clinical presentations of nonneuroinvasive WNV and dengue fever are similar, and symptoms may include acute onset of high fever, headache, myalgia, arthralgia, nausea, vomiting, and often a maculopapular rash. More serious manifestations of these viruses include fatal encephalitis and meningitis in WNV patients and fatal hemorrhagic disease in dengue patients. Over the last decade, WNV has spread rapidly across North America, reaching Arizona in 2004, and has become a significant cause of human illness since that time. Even though dengue has been described as primarily a disease of the tropics and sub-tropical areas, there is a small but significant risk for dengue outbreaks in the continental United States as evidenced by surveillance efforts in Texas that identified local dengue transmission in 2005. In recent years, outbreaks of dengue have occurred in Mexico border states, most notably Sonora in 2010. That same year, Arizona had the highest incidence of WNV cases in the U.S. including number of neuroinvasive disease cases, total cases, and number of deaths per state. The emergence of DENV and WNV as important public health problems maybe have been due to non-effective mosquito control, global demographic changes (urbanization and population growth), increased air travel, and inadequate surveillance.

Objective:

To enhance arboviral surveillance and laboratory capacity to establish a surveillance baseline for the emerging threat of Dengue fever in the Arizona-Mexico border region.

 

Since 2003 some Arizona counties have followed mosquito surveillance protocols to trap the West Nile Virus vector, Culex spp., using CO2 traps. Despite low sensitivity of these traps to detect Aedes spp., one out of seven CO2 traps deployed in Santa Cruz County detected Aedes aegypti in 2014. Enhancing surveillance for Aedes spp. in this region is critical, given that local transmission of dengue has occured across the border in Nogales, Sonora. Limited resources in Santa Cruz County have previously inhibited efforts to enhance mosquito surveillance . To broaden the reach of county surveillance, we implemented a community participatory project by engaging residents to conduct ovitrapping, a non-technical trap that attracts Aedes spp.

Objective

The objective of this work is to develop an efficient communitybased strategy to enhance mosquito surveillance for Aedes spp., vector for chikungunya and dengue viruses, in Santa Cruz County on the U.S.-Mexico border. We aim to determine vector presence, distribution, and seasonality by using ovitraps maintained by community members.

Zika, chikungunya, and dengue have surged in the Americas over the past several years and pose serious health threats in regions of the U.S. where Ae. aegypti and Ae. albopictus mosquito vectors occur. Ae. aegypti have been detected up to 6 months of the year or longer in parts of Arizona, Florida, and Texas where mosquito surveillance is regularly conducted. However, many areas in the U.S. lack basic data on vector presence or absence. The Zika, dengue, and chikungunya viruses range in pathogenicity, but all include asymptomatic or mild presentations for which individuals may not seek care. Traditional passive surveillance systems rely on confirmatory laboratory testing and may not detect emergent disease until there is high morbidity in a community or severe disease presentation. Participatory surveillance is an approach to disease detection that allows the public to directly report symptoms electronically and provides rapid visualization of aggregated data to the user and public health agencies. Several such systems have been shown to be sensitive, accurate, and timelier than traditional surveillance. We developed Kidenga, a mobile phone app and participatory surveillance system, to address some of the challenges in early detection of day-biting mosquitoes and Aedes-borne arboviruses and to enhance dissemination of information to at-risk communities. 

Objective

(1) Early detection of Aedes-borne arboviral disease;

(2) improved data on Ae. aegypti and Ae. albopictus distribution in the United States (U.S.); and

(3) education of clinicians and the public.