Background: The combination ofWolbachia-based incompatible insect technique (IIT) and radiation-based sterile insect technique (SIT) can be used for population suppression ofAedes aegypti. Our main objective was to evaluate whether open-field mass-releases ofwAlbB-infectedAe.aegyptimales, as part of an Integrated Vector Management (IVM) plan led by the Mexican Ministry of Health, could suppress natural populations ofAe.aegyptiin urbanized settings in south Mexico.Methodology/Principal findings: We implemented a controlled before-and-after quasi-experimental study in two suburban localities of Yucatan (Mexico): San Pedro Chimay (SPC), which received IIT-SIT, and San Antonio Tahdzibichén used as control. Release ofwAlbBAe.aegyptimales at SPC extended for 6 months (July-December 2019), covering the period of higherAe.aegyptiabundance. Entomological indicators included egg hatching rates and outdoor/indoor adult females collected at the release and control sites. Approximately 1,270,000 lab-producedwAlbB-infectedAe.aegyptimales were released in the 50-ha treatment area (2,000wAlbBAe.aegyptimales per hectare twice a week in two different release days, totaling 200,000 male mosquitoes per week). The efficacy of IIT-SIT in suppressing indoor femaleAe.aegyptidensity (quantified from a generalized linear mixed model showing a statistically significant reduction in treatment versus control areas) was 90.9% a month after initiation of the suppression phase, 47.7% two months after (when number of released males was reduced in 50% to match local abundance), 61.4% four months after (when initial number of released males was re-established), 88.4% five months after and 89.4% at six months after the initiation of the suppression phase. A proportional, but lower, reduction in outdoor femaleAe.aegyptiwas also quantified (range, 50.0–75.2% suppression).Conclusions/Significance: Our study, the first open-field pilot implementation ofWolbachiaIIT-SIT in Mexico and Latin-America, confirms that inundative male releases can significantly reduce natural populations ofAe.aegypti. More importantly, we present successful pilot results of the integration ofWolbachiaIIT-SIT within a IVM plan implemented by Ministry of Health personnel.

Quantification of adult Aedes aegypti abundance indoors has relied on estimates of relative density (e.g. number of adults per unit of sampling or time), most commonly using traps or timed collections using aspirators. The lack of estimates of the sensitivity of collections and lack of a numerical association between relative and the absolute density of adult Ae. aegypti represent a significant gap in vector surveillance. Here, we describe the use of sequential removal sampling to estimate absolute numbers of indoor resting Ae. aegypti and to calculate calibration coefficients for timed Prokopack aspirator collections in the city of Merida, Yucatan State, Mexico. The study was performed in 200 houses that were selected based on recent occurrence of Aedes-borne viral illness in residents. Removal sampling occurred in 10-minute sampling rounds performed sequentially until no Ae. aegypti adult was collected for 3 hours or over 2 consecutive 10-minute periods. A total of 3439 Ae. aegypti were collected. The sensitivity of detection of positive houses in the first sampling round was 82.5% for any adult Ae. aegypti, 78.5% for females, 75.5% for males and 73.3% for blood-fed females. The total number of Ae. aegypti per house was on average ~5 times higher than numbers collected for the first sampling round. There was a positive linear relationship between the relative density of Ae. aegypti collected during the first 10-min round and the absolute density for all adult metrics. Coefficients from the linear regression were used to calibrate numbers from 10-min collections into estimates of absolute indoor Ae. aegypti density for all adults, females and males. Exhaustive removal sampling represents a promising method for quantification of absolute indoor Ae. aegypti density, leading to improved entomological estimates of mosquito distribution, a key measure in the assessments of the risk pathogen transmission, disease modeling and the evaluation of vector control interventions.

Respiratory viruses represent a world public health problem, giving rise to annual seasonal epidemics and several pandemics caused by some of these viruses, including the COVID-19 pandemic caused by the novel SARS-CoV-2, which continues to date. Some antiviral drugs have been licensed for the treatment of influenza, but they cause side effects and lead to resistant viral strains. Likewise, aerosolized ribavirin is the only drug approved for the therapy of infections by the respiratory syncytial virus, but it possesses various limitations. On the other hand, no specific drugs are licensed to treat other viral respiratory diseases. In this sense, natural products and their derivatives have appeared as promising alternatives in searching for new compounds with antiviral activity. Besides their chemical properties, quinones have demonstrated interesting biological activities, including activity against respiratory viruses. This review summarizes the activity against respiratory viruses and their molecular targets by the different types of quinones (both natural and synthetic). Thus, the present work offers a general overview of the importance of quinones as an option for the future pharmacological treatment of viral respiratory infections, subject to additional studies that support their effectiveness and safety.

Receptor-binding specificity is a major determinant of host range, pathogenesis, and interspecies transmission in influenza virus. Recognition of different conformations of sialic acid by the influenza virus hemagglutinin has driven influenza intra- and interspecies transmission for nearly 100 years since the first human pandemic was recorded in 1918. Key amino acid residues near or at the receptor-binding site of the hemagglutinin of different influenza A subtypes correlate with the ability of the virus to infect and replicate in the upper or lower respiratory tract of the host and transmit efficiently. A global concern exists for those highly pathogenic avian viruses that have emerged with the potential to cause a novel pandemic in humans. Studying the receptor-binding affinity to sialic acid receptors as a marker of pandemic risk could provide reliable measures to aid in timely pandemic planning and surveillance worldwide.

Arbovirus infection inAedes aegyptihas historically been quantified from a sample of the adult population by pooling collected mosquitoes to increase detectability. However, there is a significant knowledge gap about the magnitude of natural arbovirus infection within areas of active transmission, as well as the sensitivity of detection of such an approach. We used indoorAe. aegyptisequential sampling with Prokopack aspirators to collect all mosquitoes inside 200 houses with suspected active ABV transmission from the city of Mérida, Mexico, and tested all collected specimens by RT-PCR to quantify: a) the absolute arbovirus infection rate in individually testedAe. aegyptifemales; b) the sensitivity of using Prokopack aspirators in detecting ABV-infected mosquitoes; and c) the sensitivity of entomological inoculation rate (EIR) and vectorial capacity (VC), two measures ABV transmission potential, to different estimates of indoorAe.aegyptiabundance. The total number ofAe.aegypti(total catch, the sum of allAe.aegyptiacross all collection intervals) as well as the number on the first 10-min of collection (sample, equivalent to a routine adult aspiration session) were calculated. We individually tested by RT-PCR 2,161Aedes aegyptifemales and found that 7.7% of them were positive to any ABV. Most infections were CHIKV (77.7%), followed by DENV (11.4%) and ZIKV (9.0%). The distribution of infectedAedes aegyptiwas overdispersed; 33% houses contributed 81% of the infected mosquitoes. A significant association between ABV infection andAe.aegyptitotal catch indoors was found (binomial GLMM, Odds Ratio > 1). A 10-min indoor Prokopack collection led to a low sensitivity of detecting ABV infection (16.3% for detecting infected mosquitoes and 23.4% for detecting infected houses). When averaged across all infested houses, mean EIR ranged between 0.04 and 0.06 infective bites per person per day, and mean VC was 0.6 infectious vectors generated from a population feeding on a single infected host per house/day. Both measures were significantly and positively associated withAe.aegyptitotal catch indoors. Our findings provide evidence that the accurate estimation and quantification of arbovirus infection rate and transmission risk is a function of the sampling effort, the local abundance ofAedes aegyptiand the intensity of arbovirus circulation.