The Eco-Bio-Social Factors That Modulate Aedes aegypti Abundance in South Texas Border Communities

Vector mosquito distribution and richness are predicted by socio-economic, and ecological variables

Mosquitoes of vectorial importance represent a ubiquitous and constant threat of potentially devastating arboviral outbreaks. Our ability to predict such outcomes is still restricted. To answer this, we have used an extensive data collection of 23 vector and 233 non-vector mosquito species distributed throughout the Mexican territory and linked them to social and environmental factors. Our aim was to predict vector and non-vector mosquitoes' distribution and species richness based on socioeconomic and environmental data. We found that lack of health services, human population variation, ecological degradation, and urban-rural categorization contributed significantly to explain the distribution of vector mosquitoes. mosquitoes. This phenomenon is probably attributed to the degradation of natural ecosystems as it creates favorable conditions for the proliferation of vector mosquitoes. The richness of vector mosquitoes was similarly explained by most of these variables as well as altitude. As for non-vector mosquitoes, social marginalization, ecological degradation, anthropogenic impact, and altitude explain species richness and distribution. These findings illustrate the complex interaction of environmental and socioeconomic factors behind the distribution of mosquitoes, and the potential for arboviral disease outbreaks. Areas with human populations at highest risk for mosquito-borne diseases should be primary targets for vector control.

Is the presence of mosquitoes an indicator of poor environmental sanitation?

The World Health Organization has designated mosquitoes as the most lethal animal since they are known to spread pathogen-transmitting organisms. Understanding the many environmental elements that contribute to the spread of these vectors is one of the many strategies used to stop them. If there are mosquitoes around people, it may indicate that there is not an appropriate environmental sanitation program in place in the community or region. Environmental sanitation involves improving any elements of the physical environment that could have a negative impact on a person's survival, health, or physical environment. Keywords containing 'Aedes,' 'Culex,' 'Anopheles,' 'dengue,' 'malaria,' 'yellow fever,' 'Zika,' 'West Nile,' 'chikungunya,' 'resident,' 'environment,' 'sanitation,' 'mosquito control,' and 'breeding sites' of published articles on PubMed, Google Scholar, and ResearchGate were reviewed. It was discovered that the general population should be involved in mosquito and mosquito-borne disease control. Collaboration between health professionals and the general population is essential. The purpose of this paper is to increase public awareness of environmental health issues related to diseases carried by mosquitoes.

Personality and city culture predict attitudes and practices toward mosquitoes and mosquito-borne diseases in South Texas

Personality is known to affect compliance with health-protective behaviors and it has been shown that effective public health messaging can be informed by an understanding of that relationship. Thus, we aimed to evaluate the role personality might play in implementing personal protective measures (PPMs) that can prevent mosquito-borne diseases. This is the first mosquito-related knowledge, attitudes, and practices (KAP) study to incorporate a measure of personality using the Big Five: openness, conscientiousness, extraversion, agreeableness, and neuroticism. KAP studies in Gulf-coast and Mexican border-states in the U.S. are few. Ours is only the second KAP study to take place in Texas despite known local transmission and established mosquito populations capable of transmitting dengue, zika, chikungunya, and West Nile viruses. The KAP survey was administered in three neighborhoods in San Antonio, a large, Hispanic-majority, urban city that is segregated economically and ecologically. We found that openness, agreeableness, and extraversion predicted certain attitudes and PPMs, and that KAP and personality measures did not differ along ethnic or neighborhood lines. Perceptions toward the city's role in mosquito control and education was an important factor in predicting PPMs, suggesting that city culture (attitudes common throughout the city as opposed to attitudes differing by ethnicity and neighborhood) may be most salient in developing public health messaging in San Antonio.

Control methods for Aedes aegypti: Have we lost the battle?

The past twenty years have been a period of remarkable innovation in Aedes vector control, and several methods with varying success rates have been used. Here we discussed the main intervention categories of vector control applied nowadays and their main weaknesses. It is urgent to have more efficient design and management of control programs, and the requirement for studies to evaluate and compare methods must be prioritised. The world must better articulate actions and cooperate with other sectors beyond health; it is necessary to work together with managers and entomologists in action plans and adapt them to the condition of each region.

The unreachable doorbells of South Texas: community engagement in colonias on the US-Mexico border for mosquito control

Mosquitoes and the diseases they transmit continue to place millions of people at risk of infection around the world. Novel methods of vector control are being developed to provide public health officials with the necessary tools to prevent disease transmission and reduce local mosquito populations. However, these methods will require public acceptance for a sustainable approach and evaluations at local settings. We present our efforts in community engagement carried out in colonias of the Lower Rio Grande Valley in south Texas for mosquito surveillance, control, and ecological projects. Along the US-Mexico border the term colonia refers to impoverished communities that are usually inhabited by families of Hispanic heritage. The different engagements were carried out from September 2016 to February 2019; during this time, we had three distinct phases for community engagement. In Phase 1 we show the initial approach to the colonias in which we assessed security and willingness to participate; in Phase 2 we carried out the first recruitment procedure involving community meetings and house-to-house recruitment; and in Phase 3 we conducted a modified recruitment procedure based on community members' input. Our findings show that incorporating community members in the development of communication materials and following their suggestions for engagement allowed us to generate culturally sensitive recruitment materials and to better understand the social relationships and power dynamics within these communities. We were able to effectively reach a larger portion of the community and decrease the dropout rate of participants. Progress gained with building trust in the communities allowed us to convey participant risks and benefits of collaborating with our research projects. Community engagement should be viewed as a key component of any local vector control program as well as for any scientific research project related to vector control. Even in the face of budgetary constraints, small efforts in community engagement go a long way.

Variable coverage in an Autocidal Gravid Ovitrap intervention impacts efficacy of Aedes aegypti control

Control of the arboviral disease vector Aedes aegypti has shown variable levels of efficacy around the globe. We evaluated an Autocidal Gravid Ovitrap (AGO) intervention as a stand-alone control tool for population suppression of A. aegypti in US communities bordering Mexico.We conducted a cluster randomized crossover trial with weekly mosquito surveillance of sentinel households from July 2017 to December 2018. The intervention took place from August to December of both years. Multilevel models (generalized linear and additive mixed models) were used to analyse the changes in population abundance of female A. aegypti.We observed that female populations were being suppressed 77% (2018) and four times lower outdoor female abundance when AGO coverage (number of intervention AGO traps that surrounded a sentinel home) was high (2.7 AGOs/house). However, we also observed that areas with low intervention AGO coverage resulted in no difference (2017) or slightly higher abundance compared to the control. These results suggest that coverage rate might play a critical role on how populations of female A. aegypti are being modulated in the field. The lack of larval source habitat reduction and the short duration of the intervention period might have limited the A. aegypti population suppression observed in this study. Synthesis and applications. The mosquito, A. aegypti, is a public health concern in most tropical and subtropical regions. With the rise of insecticide resistance, the evaluation of non-chemical tools has become pivotal in the fight against arboviral disease transmission. Our study shows that the AGO intervention, as a stand-alone control tool, is limited by its coverage in human settlements. Vector control programmes should consider, that if the target coverage rate is not achieved, measures will be ineffective unless coupled with other control approaches. Although our multilevel modelling was focused on A. aegypti and the AGO, the approach can be applied to other mosquito vector species.

Ecological, Social, and Other Environmental Determinants of Dengue Vector Abundance in Urban and Rural Areas of Northeastern Thailand

Aedes aegypti is the main vector of dengue globally. The variables that influence the abundance of dengue vectors are numerous and complex. This has generated a need to focus on areas at risk of disease transmission, the spatial-temporal distribution of vectors, and the factors that modulate vector abundance. To help guide and improve vector-control efforts, this study identified the ecological, social, and other environmental risk factors that affect the abundance of adult female and immature Ae. aegypti in households in urban and rural areas of northeastern Thailand. A one-year entomological study was conducted in four villages of northeastern Thailand between January and December 2019. Socio-demographic; self-reported prior dengue infections; housing conditions; durable asset ownership; water management; characteristics of water containers; knowledge, attitudes, and practices (KAP) regarding climate change and dengue; and climate data were collected. Household crowding index (HCI), premise condition index (PCI), socio-economic status (SES), and entomological indices (HI, CI, BI, and PI) were calculated. Negative binomial generalized linear models (GLMs) were fitted to identify the risk factors associated with the abundance of adult females and immature Ae. aegypti. Urban sites had higher entomological indices and numbers of adult Ae. aegypti mosquitoes than rural sites. Overall, participants’ KAP about climate change and dengue were low in both settings. The fitted GLM showed that a higher abundance of adult female Ae. aegypti was significantly (p < 0.05) associated with many factors, such as a low education level of household respondents, crowded households, poor premise conditions, surrounding house density, bathrooms located indoors, unscreened windows, high numbers of wet containers, a lack of adult control, prior dengue infections, poor climate change adaptation, dengue, and vector-related practices. Many of the above were also significantly associated with a high abundance of immature mosquito stages. The GLM model also showed that maximum and mean temperature with four-and one-to-two weeks of lag were significant predictors (p < 0.05) of the abundance of adult and immature mosquitoes, respectively, in northeastern Thailand. The low KAP regarding climate change and dengue highlights the engagement needs for vector-borne disease prevention in this region. The identified risk factors are important for the critical first step toward developing routine Aedes surveillance and reliable early warning systems for effective dengue and other mosquito-borne disease prevention and control strategies at the household and community levels in this region and similar settings elsewhere.