Henry Puerta-Guardo

By Henry Puerta-Guardo, Scott B. Biering, Eva Harris, Norma Pavia-Ruz, Gonzalo Vázquez-Prokopec, Guadalupe Ayora-Talavera and Pablo Manrique-Saide

Dengue is the most prevalent emerging mosquito-borne viral disease, affecting more than 40% of the human population worldwide. Many symptomatic dengue virus (DENV) infections result in a relatively benign disease course known as dengue fever (DF). However, a small proportion of patients develop severe clinical manifestations, englobed in two main categories known as dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Secondary infection with any of the four dengue virus serotypes (DENV1, -2, -3, and -4) is a risk factor to develop severe forms of dengue disease. DSS is primarily characterized by sudden and abrupt endothelial dysfunction, resulting in vascular leak and organ impairment, which may progress to hypovolemic shock and death. Severe DENV disease (DHF/DSS) is thought to follow a complex relationship between distinct immunopathogenic processes involving host and viral factors, such as the serotype cross-reactive antibody-dependent enhancement (ADE), the activation of T cells and complement pathways, the phenomenon of the cytokine storm, and the newly described viral toxin activity of the nonstructural protein 1 (NS1), which together play critical roles in inducing vascular leak and virus pathogenesis. In this chapter that is divided in two parts, we will outline the recent advances in our understanding of DENV pathogenesis, highlighting key viral-host interactions and discussing how these interactions may contribute to DENV immunopathology and the development of vascular leak, a hallmark of severe dengue. Part I will address the general features of the DENV complex, including the virus structure and genome, epidemiology, and clinical outcomes, followed by an updated review of the literature describing the host innate immune strategies as well as the viral mechanisms acting against and in favor of the DENV replication cycle and infection.

Part of the book: Dengue Fever in a One Health Perspective

By Yamili J. Contreras-Perera, Abdiel Martin-Park, Henry Puerta-Guardo, Azael Che-Mendoza, Silvia Pérez-Carrillo, Irám Pablo Rodríguez-Sánchez, Pablo Manrique-Saide and Adriana Flores-Suarez

Mosquito’s resistance to avoiding insecticide-treated surfaces (“excito-repellency”) has two effects: irritation from direct contact with a treated area and repellency as an avoidance response to contact with treated surfaces. Nowadays, this behavior appears to reduce the success of mosquito control programs, particularly those based on insecticide-driven strategies. Different systems have been designed to assess the excito-repellency, evaluating numerous insecticides’ irritants, deterrents, and toxic properties at different concentrations. The information provides valuable insights regarding the patterns of mosquito behavior based on their physiological conditions, such as the age of the mosquitoes and the duration of the tests. However, the physiological processes resulting from chemical stimulus contact “chemoreception”) are still poorly explored and understood. This review provides an overview of insecticide effects on mosquito behavior and describes the mechanisms involved in chemical stimuli uptake, translation, and recognition.

Part of the book: Mosquito Research

By Josué Villegas-Chim, Abdiel Martin-Park, Henry Puerta-Guardo, María Eugenia Toledo-Romaní, Norma Pavía-Ruz, Yamili Contreras-Perera, Silvia Pérez-Carrillo, Azael Che-Mendoza, Jorge Palacio-Vargas, Fabián Correa-Morales, Héctor Gómez-Dantés and Pablo Manrique-Saide

The Wolbachia-based approach is under evaluation as a control strategy against Aedes aegypti in Mexico. From 2017 to 2019, we performed a pilot study to evaluate an open-field mass-release of wAlbB-infected Ae. aegypti male mosquitoes, as part of an integrated vector management (IVM) plan led by the Ministry of Health in Mexico to suppress natural populations of Ae. aegypti in southern Mexico. Community engagement and social evaluation were part of the key activities conducted. Overall, results showed the positive benefits of this Wolbachia-based method in the reduction of Aedes mosquitoes (90%). Mosquito’s nuisance at bedtime and the increasing circulation of mosquitoes during the releasing days were reported as the negative perceptions of this method. Importantly, participants understood the difference between wild mosquitoes and those released as part of the project, as well as the importance of the IVM. A significant number of the population accepted and supported the project, and feedback was given to improve future mosquito-releasing activities. The social license was a key factor in the success of the intervention and should be part of innovative paradigms for mosquito-vector control strategies involving community engagement. We outline the Mexican experience of community engagement and social assessment in implementing a Wolbachia-based strategy.

Part of the book: Mosquito Research

By Josué Herrera-Bojórquez, Josué Villegas-Chim, Daniel Adrian, Azael Che-Mendoza, Juan Navarrete-Carballo, Anuar Medina-Barreiro, Miguel Xcaer, Hugo Delfín-González, Norma Pavía-Ruz, Henry Puerta-Guardo, María Eugenia Toledo-Romaní, Héctor Gómez-Dantés, Gonzalo Vazquez-Prokopec and Pablo Manrique-Saide

House-screening (HS) using fixed-aluminium frames to reduce the risk of indoor infestation with Aedes aegypti mosquitoes as well as the risk of Aedes-transmitted diseases in communities living in endemic areas. However, the success of this approach has been hindered by the elevated cost of the aluminium-based materials as well as their professional installation, which cannot be afforded by people living under vulnerable conditions. Cost-saving strategies such as the use of low-cost materials including wood, PVC, and Velcro are within the list of HS options available and offered by HS businesses and/or Do-it-yourself (DIY) packages verbi gratia ready-made and ready-to-install mosquito-screens. Here, we evaluated the efficacy of low-cost frames constructed with different materials to protect against Ae. aegypti indoor infestation using experimental huts. The efficacy of protection in preventing female mosquito passing inside the huts of any of the options of frames was high (>93%) compared to the control with no-screen. People’s perceptions on the different materials showed the most “popular” alternative was the frame made of wood (62%). All the prototype-frames of HS made of different materials were effective at blocking Ae. aegypti entering-mosquitoes particularly, low-cost options like magnets and Velcro.

Part of the book: Mosquito Research