Analyzing morphometry among extant and extinct species: A case study of genus Agassizia (Spatangoida: Echinoidea) / Análisis de la morfometría entre especies existentes y extintas: Un estudio de caso del género Agassizia (Spatangoida: Echinoidea)

Abstract Introduction: The genus Agassizia in Mexico is represented both in the fossil record by the species Agassizia regia† during the Miocene of Chiapas and by the extant species Agassizia excentrica on the Atlantic coast and Agassizia scrobiculata on the Pacific coast. Qualitative diagnosis and descriptions make it hard to distinguish morphological boundaries between species, especially in groups with fossils and recent representatives, increasing the level of complexity by having samples of disparate qualities and quantities. Objective: We propose the use of little explored statistical methods in the comparison of paleontological and biological populations. This methodology allowed us to resolve issues of missing values in a morphometric data set for the genus Agassizia. Methods: Using samples recently collected and specimens already housed in collections, we explore a routine of recovery of missing data MICE and the numerical and graphic analyses PERMANOVA, PCA, and SIMPER to compare morphometric parameters between these species for recognizing diagnostic characters. Results: Our results show a morphological difference in the length of the ambulacrum II and the length and width of the periproct and peristome structures, these being greater in A. scrobiculata, with a consistent pattern in both population samples not previously described. Conclusions: Quantitative morphometric comparisons can be an assertive and complementary tool to determine distinctive differentiation characteristics in species of the same genus. Comparative morphology reviews should be an ongoing exercise to keep taxonomic knowledge on both extinct and extant species up to date. Our research encourage the scientific community studying fossil populations to utilize quantitative and multivariate methods to strengthen their investigations.

Resumen Introducción: El género Agassizia en México está representado tanto en el registro fósil por la especie Agassizia regia† del Mioceno de Chiapas, como por las especies actuales Agassizia excentrica de la costa del Atlántico y Agassizia scrobiculata de la costa del Pacífico. Las descripciones y diagnosis cualitativas dificultan reconocer los limites morfológicos entre especies, especialmente en grupos con representantes fósiles y recientes, e incrementando el nivel de complejidad al tener muestras de cantidad y calidad desiguales. Objetivo: Proponemos el uso de métodos estadísticos poco explorados en la comparación de poblaciones paleontológicas y biológicas. Esta metodología nos permitió resolver problemas de valores faltantes en un conjunto de datos morfométricos para el género Agassizia. Métodos: Usando muestras recolectadas para este fin, así como provenientes de colecciones científicas, exploramos una rutina de recuperación de datos faltantes MICE, y los análisis numéricos y gráficos PERMANOVA, PCA y SIMPER para comparar parámetros morfométricos entre estas especies y reconocer caracteres de diagnóstico. Además, comparamos cuidadosamente los caracteres morfológicos descritos previamente en la literatura taxonómica y la descripción ambiental del hábitat actual de A. scrobiculata. Resultados: Nuestros resultados muestran una diferencia morfológica en la longitud del ambulacrum II y la longitud y anchura de las estructuras del periprocto y peristoma, siendo estas mayores en A. scrobiculata, con un patrón consistente en ambas muestras poblacionales no descrito previamente. El hábitat actual de las muestras de A. scrobiculata en la costa del Pacífico es un sistema costero poco profundo con sedimentos arenosos y temperaturas tropicales. Bahía Chamela comparte varias similitudes con la fauna y las condiciones ambientales previamente descritas en el Mioceno de Chiapas. Conclusiones: Las comparaciones morfométricas cuantitativas pueden ser una herramienta poderosa y complementaria para determinar caracteres distintivos de diferenciación en especies del mismo género. Las revisiones de morfología comparativa deben ser un ejercicio continuo para mantener actualizado el conocimiento taxonómico sobre las especies existentes y extintas. Nuestro trabajo busca incentivar a la comunidad científica que trabaja con poblaciones fósiles a explorar estos y otros métodos cuantitativos y multivariados para fortalecer sus investigaciones.

Molecular Evidence of Ehrlichia canis (Rickettsiales: Anaplasmataceae) in Ticks (Ixodida: Ixodidae) Associated with Dogs (Carnivora: Canidae) from Nuevo Leon, Mexico.

Background: Ehrlichia canis is transmitted by ticks causing Canine monocytic ehrlichiosis, which is considered one of the most critical tickborne pathogens. Materials and Methods: This study aimed to identify by PCR technique E. canis in ticks associated with dogs from urban and rural homes in Nuevo Leon, Mexico. The study was conducted at 13 localities in eight municipalities from 2012 to 2021. Results: A total of 1873 ticks of three species were captured: Amblyomma tenellum, Dermacentor variabilis, and Rhipicephalus sanguineus s.l. The overall infection rate of E. canis in ticks was 59.12% (149/252). Of the 15 sequences, three haplotypes were identified. Conclusion: The urban transmission cycle of canine ehrlichiosis is demonstrated, where the potential vector is the tick R. sanguineus s.l.

Species diversity, barcode, detection of pathogens and blood meal pattern in Phlebotominae (Diptera: Psychodidae) from northeastern Mexico.

More than 90 species of phlebotomines are vectors of parasites, bacteria, and viruses, which cause disease in animals and humans. Therefore, their study is necessary to establish prevention and control strategies. Mexico is an endemic country for leishmaniasis, mostly in the center and southern regions of the country, yet only few studies have been conducted in the northern part of the country. The present study aims to: (a) assess the alpha diversity of Phlebotominae in an annual cycle, (b) to correlate climatic variables with abundance, (c) to generate barcodes of these insects as part of the integrative taxonomy, and (d) to detect Leishmania, Wolbachia and blood sources in an area close to where a case of autochthonous leishmaniasis has been detected in Nuevo Leon, Mexico. A systematic sampling was conducted during three consecutive nights from 17:00 to 22:00 h., placing Shannon traps, CDC traps with incandescent light, and BG Sentinel 2 + BG Lure traps. A total catch effort of 660 nights/traps/hours was achieved, in which a total number of 707 phlebotomines (58% female and 42% male) of six species were collected and identified. The most abundant species were Psathyromyia cratifer (57%) and Psathyromyia shannoni sensu stricto (26%). The highest abundance (72%; 507/707) was collected during March, April and May 2021. Barcodes were generated for four species of phlebotomines, which represent new records for Mexico. For the molecular detection of microorganisms, 302 specimens were analyzed, although no specimens were positive for Leishmania spp. Wolbachia strains were detected in phlebotomines with an infection rate of 1.32% (4/302) and found in Pa. cratifer and Lu. cruciata. Likewise, human DNA was identified in female Lu. cruciata and Pa. cratifer phlebotomines. These findings indicate the presence of potential vector species of the parasite Leishmania spp. This result shows the need for further entomological surveillance to elucidate the transmission mechanisms in these northern areas of the country.

Design and Evaluation of a Sticky Attractant Trap for Intra-Domiciliary Surveillance of Aedes aegypti Populations in Mexico.

Surveillance consists of systematic data collection, analysis, and interpretation and is essential for planning and implementing control activities. The lack of success in the control and surveillance of the Ae. aegypti mosquito elsewhere demands the development of new accessible and effective strategies. This work aimed to develop and evaluate an adhesive lure trap for household indoor surveillance of Ae. aegypti. Based on a bibliographic review, four compounds that have significant attraction percentages for Ae. aegypti were considered. Our more effective blend was determined through preliminary bioassays using the high-throughput screening system (HITSS) and 90 × 90 cm mosquito cages. We designed a low-cost, pyramid-shaped, sticky cardboard trap to incorporate the selected blend. Semi-field 2 × 2 m cages and field tests were utilized to evaluate its effectiveness through mosquito capture percentages. In laboratory tests, blend number 2 presented an attraction percentage of 47.5 ± 4.8%; meanwhile, in semi-field cages, a 4-inch, 110 v powered fan was used to disperse the attractants, and then a similar capture percentage of 43.2 ± 4.0% was recorded. Results were recorded during the field evaluation of the at-house indoor environment and were compared with those recorded with the golden-standard BG-Sentinel trap, i.e., our prototype trapped an average of 6.0 ± 1.5 mosquitoes versus 10.0 ± 2.6. In most Latin American countries, there is a lack of formal and accessible strategies for monitoring adult populations of Ae. Aegypti; therefore, we must develop tools that reinforce entomological surveillance methods.

Molecular and Serological Identification of Anaplasma marginale and Borrelia burgdorferi in Cattle and Ticks from Nuevo Leon, Northern Mexico.

Ticks and tick-borne diseases affect livestock productivity and cause significant economic losses. Therefore, surveillance of these pathogens and vectors is paramount to reducing these effects in livestock. This study aimed to identify Anaplasma marginale and Borrelia burgdorferi sensu lato in ticks collected from cattle. Molecular biology techniques were utilized to identify A. marginale for both types of samples, i.e., ticks and bovine blood. Serology of cattle using indirect immunofluorescence assay (IFA) was conducted to determine antibodies to B. burgdorferi s.l. from seven locations in Nuevo Leon, Mexico, between 2015 and 2017. From 404 bovines, 2880 ticks were collected: Rhipicephalus microplus (2391 females and 395 males), Amblyomma spp. (51 females and 42 males) and Dermacentor variabilis (1 female). Rhipicephalus microplus represented the largest specimens captured, with 96.7% within the seven study sites. PCR processed only 15% (442) of tick samples to identify A. marginale. Field genera proportions were followed to select testing tick numbers. Results showed that 9.9% (44/442) of A. maginale infected the pooled tick species, whereas the highest percent corresponded to 9.4% (38/404) in R. microplus. Regarding the molecular analysis of blood samples, 214 of 337 (63.5%) were positive for A. maginale. In each of the seven locations, at least one bovine sample tested positive for A. maginale. Borrelia burgdorferi s.l. was not found either in the ticks or serum samples. Two A.marginale DNA nucleotide sequences obtained in this study were deposited in the GenBank with the following accession numbers OR050501 cattle, and OR050500 R.microplus tick. Results of this work point to current distribution of bovine anaplasmosis in northern Mexico.

Evaluation of aflatoxin and fumonisin co-exposure in urine samples from healthy volunteers in northern Mexico.

Aflatoxins (AF) and fumonisins (FB) are common contaminants of maize and have been associated with cancer, immune suppression, and growth stunting. In this work, AFM1 and FB1 were measured in urine samples of healthy volunteers from the metropolitan area of Monterrey, Mexico, while AF and FB were detected in foods collected near the sampling zone. Urine samples from 106 adults were analyzed using ultra-performance liquid chromatography-tandem mass spectrometry and toxins in foods were measured by fluorometry. The mean value of AFM1 and FB1 was 4.3 pg/mg creatinine from 76 samples (72 %), and 50 pg/mg creatinine from 75 samples (71 %), respectively. More than half of the samples (n = 56, 53 %) had detectable levels of both AFM1 and FB1. No differences in toxin levels were found between males and females or between age groups, but AFM1 and FB1 levels were higher (p < 0.01) when detected as a single exposure compared to co-exposed. Some significant results were found when comparing AFM1 and FB1 levels among groups of people assigned to levels of food consumption. Food samples had average concentrations of 5.3 µg/kg for AF and 800 µg/kg for FB. The results showed that co-exposure to AF and FB is common in the metropolitan area of Monterrey.

Benefits of Cardamom (Elettaria cardamomum (L.) Maton) and Turmeric (Curcuma longa L.) Extracts for Their Applications as Natural Anti-Inflammatory Adjuvants.

The genus Zingiberaceae has been widely used for phytotherapeutic purposes in traditional medicine throughout the world for its anti-inflammatory activity. Experimental studies have established that inflammation caused by chronic infections represents a risk factor for different forms of cancer. The objective of this study was focused on determining the anti-inflammatory capacity and cytotoxic activity of aqueous extracts of Elettaria cardamomum (cardamom) and Curcuma Longa (turmeric). The extracts were obtained by maceration and, through GC-MS/MS, a total of 11 different chemical components were determined in the aqueous extract of cardamom and 7 in the extract of turmeric. The main compounds found in cardamom and turmeric were α-terpinyl acetate (54.46%) and ß-turmerone (33.45%), respectively. RT-qPCR results showed significantly lower gene expression levels of innate inflammatory cytokines (IL-6 and TNF-α) compared to the control (LPS). Also, it was observed that the extracts do not possess cytotoxic activity against different cell lines, where E. cardamomum showed EC50 (µg/mL) of 473.84 (HeLa cells), 237.36 (J774A.1 cells), 257.51 (Vero E6 cells), and 431.16 (Balb/C peritoneal cells) and C. longa showed EC50 (µg/mL) of 351.17 (HeLa cells), 430.96 (J774A.1 cells), 396.24 (Vero E6 cells), and 362.86 (Balb/C peritoneal cells). The results of this research suggest that natural extracts of E. cardamomum and C. longa possess anti-inflammatory effects and no cytotoxic activity against HeLa, J774A.1, Vero E6, and Balb/C peritoneal cell lines. Finally, it was observed that the extracts also decreased nitric oxide (NO) production in peritoneal macrophages.

Antimicrobial and Antibiofilm Effect of Hydrogel with Origanum vulgare on Culture of Streptococcus mutans and Streptococcus sobrinus / Efecto Antimicrobiano y Antibiofilm de Hidrogel a Base de Origanum vulgare sobre Cultivo de Streptococcus mutans y Streptococcus sobrinus

The oral cavity is an ecosystem that provides ideal conditions for the growth of bacteria, the Streptococcus genus is important for the formation of biofilms that lead to the development of dental caries, which affects the population worldwide. The world health organization encourages the use of plants thanks to its various therapeutic actions. Origanum vulgare L. (oregano), is an aromatic plant with medicinal and culinary properties. The objective of this study was to investigate the in vitro antimicrobial and antibiofilm activity of the ethanolic extract of oregano, against the growth of Streptococcus mutans and Streptococcus sobrinus ATCC. Leaves of the plant were obtained and the ethanolic extract was made by maceration. Antimicrobial activity was evaluated using the Kirby-Bauer method and compared with 2% chlorhexidine, subsequently the extract was incorporated into a hydrogel and its effect on biofilm formation was assessed by fluorescence microscopy and the main compounds were identified. present in the extratco. The study revealed that the extract presented antimicrobial effect against both strains and at 2% it showed high antimicrobial action compared to chlorhexidine at the same concentration, with average inhibition halos of 26.3 mm and 19 mm for each microorganism analyzed, (p < 0.05). Likewise, the hydrogel prepared with 2% extract significantly eliminated the preformed Streptococcus biofilm, at 24 hours of exposure, due to the presence of a variety of chemical groups, such as sterols, triterpenes, flavonoids, flavanones, flavanonol s, lactones. sesquiterpenic, tannins and coumarins. The oregano extract presented high antimicrobial action for both species, with a greater effect towards Streptococcus mutans and an interesting antibiofilm action; These results show the importance of exploring treatment alternatives of plant origin, to be considered as interesting complementary aids in dental therapy.

La cavidad oral es un ecosistema que proporciona condiciones ideales para el crecimiento de bacterias, el género Streptococcus es importante para la formación de biopelículas que conducen al desarrollo de caries dental, que afecta a la población a nivel mundial. La organización mundial de la salud, fomenta el uso de plantas gracias a sus diversas acciones terapéuticas. Origanum vulgare L. (orégano), es una planta aromática con propiedades medicinales y culinarias. El objetivo de este estudio fue investigar la actividad antimicrobiana y antibiofilm in vitro del extracto etanólico de oregano, contra el crecimiento de Streptococcus mutans y Streptococcus sobrinus ATCC. Se obtuvierón hojas de la planta y se realizó el extracto etanólico mediante maceración. La actividad antimicrobiana se evaluó mediante el método de Kirby-Bauer y se comparó con la clorhexidina al 2 %, posteriormente se incorporó el extracto en un hydrogel y se valoró su efecto sobre la formación del biofilm mediante microscopía de fluorescencia y se identificó los principales compuestos presentes en el extratco. El estudio reveló que el extracto presentó efecto antimicrobiano contra ambas cepas y al 2 % mostró alta acción antimicrobiana en comparación con la clorhexidina a la misma concentración, con halos de inhibición promedio de 26.3 mm y de 19 mm para cada microorganismo analizado, (p < 0.05). Así mismo, el hidrogel preparado con extracto al 2 %, eliminó significativamente la biopelícula preformada de Streptococcus, a las 24 horas de exposición, debido a la presencia de una variedad de grupos químicos, como esteroles, triterpenos, flavonoides, flavanonas, flavanonoles, lactonas sesquiterpénicas, taninos y cumarinas. El extracto de orégano presentó alta acción antimicrobiana para ambas especies, con mayor efecto hacia el Streptococcus mutans y una acción antibiofilm interesante; estos resultados muestran la importancia de explorar en alternativas de tratamiento de origen vegetal, para considerarse como auxiliares complementarios interesantes en la terapia dental.

Echinoderms (Echinodermata) from the Central Mexican Pacific / Equinodermos (Echinodermata) del Pacífico Central mexicano

Introduction: The echinoderms from the Central Mexican Pacific are of high scientific interest and, prior to this present work, there was a lack of basic information that included incomplete checklists with inconsistencies in systematics and spatial distribution. Objective: To provide a historical review, and an updated checklist with a more complete richness of echinoderms for each state and island of the region. Methods: A checklist was elaborated based on an exhaustive literature search of the Echinodermata, and was complemented with taxonomical revisions of Ophiuroidea scientific collections. All the geographical coordinates of the records were validated. Results: The region harbors 187 species of Echinodermata: three Crinoidea, 35 Asteroidea, 67 Ophiuroidea, 32 Echinoidea, and 50 Holothuroidea. We detected 52 records in the literature that must be considered as invalid and five as doubtful. We provide 16 new records of Ophiuroidea from different states and islands; of them, four are new records for the region. Jalisco presented the highest number of species (84), followed by the coast of Nayarit (74), Michoacán (63), and Colima (55); among the islands, Revillagigedo showed the major number of species (85) followed by Marías (81), Marietas (48), and Isabel (44). Conclusions: The numbers of species known in the region are mostly related to both sampling effort and environmental characteristics that promote high biodiversity. The Central Mexican Pacific is an oceanographic region with mixed conditions from the North and South of the Mexican Pacific, and therefore, with a biogeographical importance reflected in its species richness.

Introducción: Los equinodermos del Pacífico Central mexicano poseen un alto interés científico, pero anterior al presente trabajo existía un vacío en la información básica como listados de especies incompletos con inconsistencias sistemáticas y de distribución espacial. Objetivo: Proporcionar una revisión histórica y un listado de especies actualizado con la riqueza completa de equinodermos para cada estado e islas de la región. Métodos: Se elaboró un listado de especies basado en una búsqueda exhaustiva de Echinodermata, y fue complementada con la revisión taxonómica de Ophiuroidea de colecciones científicas. Todas las coordenadas geográficas de los registros fueron validadas. Resultados: La región posee 187 especies de Echinodermata: tres Crinoidea, 35 Asteroidea, 67 Ophiuroidea, 32 Echinoidea, y 50 Holothuroidea. Detectamos 52 registros en la literatura considerados como inválidos y cinco como dudosos. Proveemos 16 nuevos registros de Ophiuroidea para diversos estados e islas; de estos, cuatro son nuevos registros para la región. Jalisco presentó el mayor número de especies (84), seguido por las costas de Nayarit (74), Michoacán (63), y Colima (55); entre las islas, Revillagigedo presentó el mayor número de especies (85) seguido por Marías (81), Marietas (48), e Isabel (44). Conclusiones: Los números de especies de la región están mayormente relacionados tanto con el esfuerzo de muestreo como con características ambientales que promueven una alta biodiversidad. El Pacífico Central mexicano es una región oceanográfica con condiciones mixtas del norte y sur del Pacífico mexicano, y por lo tanto con una importancia biogeográfica reflejada en la riqueza de la región.

Pediculosis Affects Mexican Children from Different Socioeconomic Status Equally: A Cross-Sectional Study.

The prevalence of pediculosis in Mexican children was studied in San Nicolas and Tapachula, Mexico. A cross-sectional study included 888 students between six and 12 years old from two urban communities with an unequal socioeconomic status between September 2015 and March 2016. A Pearson χ2 and multivariate logistic analysis were carried out to associate risk factors to pediculosis. The overall prevalence of pediculosis from both localities was 23.9%. The female gender; long and medium hair; living with someone infested; previously infested by head lice and curling hair were variables linked to a significantly higher prevalence of pediculosis (p < 0.01). Nevertheless, no significant differences were observed in the age groups, localities and socioeconomic status for human lice infection. Socioeconomic variables such as numbers of inhabitants, floors of house, beds and rooms; and parents' qualification did not show a significative association for pediculosis. Health education in schools is needed for pediculosis prevention and remove the stigmatization of this disease related to poverty.

Temporal Viability of Aedes aegypti and Aedes albopictus Eggs Using Two Hygroscopic Substances as Preservatives under a Sterile Insect Technique (SIT) Program in Southern Mexico.

Dengue and other Aedes-borne diseases have dramatically increased over the last decades. The Sterile Insect Technique (SIT) has been successfully used as part of integrated pest strategies to control populations of insect-plant and livestock pests and is currently being tested as a potential method to reduce mosquito populations in an environmentally friendly approach. However, during the mass rearing steps needed to produce millions of mosquitoes, egg storage and preservation are essential for a certain amount of time. Eggs of Aedes aegypti have a chorionic pad that functions as a sticky substance to glue them onto the inner walls of larval breeding sites. The chorionic pad is chemically made of hyaluronic acid, a hygroscopic compound, responsible to protect them from desiccation over time. Two commercial products with hygroscopic properties, hydrolyzed collagen, and Hyalurosmooth®, both were tested to assess their ability to prolong egg life storage for A. aegypti and A. albopictus. Results showed that 85-95% of Ae. aegypti eggs were able to hatch up to week 8 after being treated with both hydrophilic compounds, compared with the control 66.3%. These two substances showed promising effects for keeping Ae. aegypti eggs viable during prolonged storage in mass rearing insect production focused on vector control SIT programs.

Clinical Symptoms of Arboviruses in Mexico.

Arboviruses such as Chikungunya (CHIKV), Dengue (DENV), and Zika virus (ZIKV) have emerged as a significant public health concern in Mexico. The existing literature lacks evidence regarding the dispersion of arboviruses, thereby limiting public health policy's ability to integrate the diagnosis, management, and prevention. This study seeks to reveal the clinical symptoms of CHIK, DENV, and ZIKV by age group, region, sex, and time across Mexico. The confirmed cases of CHIKV, DENV, and ZIKV were compiled from January 2012 to March 2020. Demographic characteristics analyzed significant clinical symptoms of confirmed cases. Multinomial logistic regression was used to assess the association between clinical symptoms and geographical regions. Females and individuals aged 15 and older had higher rates of reported significant symptoms across all three arboviruses. DENV showed a temporal variation of symptoms by regions 3 and 5, whereas ZIKV presented temporal variables in regions 2 and 4. This study revealed unique and overlapping symptoms between CHIKV, DENV, and ZIKV. However, the differentiation of CHIKV, DENV, and ZIKV is difficult, and diagnostic facilities are not available in rural areas. There is a need for adequately trained healthcare staff alongside well-equipped lab facilities, including hematological tests and imaging facilities.

Wine Intake in the Framework of a Mediterranean Diet and Chronic Non-Communicable Diseases: A Short Literature Review of the Last 5 Years.

Dietary habits are a determining factor of the higher incidence and prevalence of chronic non-communicable diseases (NCDs). In the aim to find a possible preventive and intervention strategy, the Mediterranean diet (MedDiet) has been proposed as an effective approach. Within the MedDiet, moderate wine consumption with meals is a positive item in the MedDiet score; however, recent studies have reported a dose-response association between alcohol consumption and higher risk of a large number of NCDs. This review aimed to evaluate the association between NCDs and wine consumption in the framework of the MedDiet, with a simple review of 22 studies of the highest-level literature published over the last five years. We found that the information regarding the effects of wine in different health outcomes has not varied widely over the past five years, finding inconclusive results among the studies evaluated. Most of the literature agrees that light to moderate wine intake seems to have beneficial effects to some extent in NCDs, such as hypertension, cancer, dyslipidemia and dementia, but no definitive recommendations can be made on a specific dose intake that can benefit most diseases.

Molecular Detection of Leptospira interrogans and Borrelia burgdorferi in Wild Rodents from Mexico.

Leptospirosis and Lyme borreliosis are zoonotic emerging diseases of global importance and wide distribution. The aim of this study was to detect by molecular testing to Leptospira interrogans and Borrelia burgdorferi sensu lato in wild rodents from Nuevo Leon, Quintana Roo, and Campeche, Mexico. This study is the first in report to Chaetodipus nelsoni, Dipodomys merriami, and Peromyscus eremicus infected with L. interrogans in Mexico. Besides, Chaetodipus hispidus, Heteromys gaumeri, Heteromys irroratus, Neotoma micropus, Peromyscus leucopus, Peromyscus maniculatus, and Sigmodon hispidus infected with B. burgdorferi s.l. in Mexico. Also, is the first report in identify coinfection of L. interrogans and B. burgdorferi s.l. in wild rodents such as H. irroratus and S. hispidus in Nuevo Leon, and H. gaumeri in Quintana Roo, Mexico. These wild rodent species infected represent a risk factor for the exposed population in these sylvatic and rural areas of Mexico.

Outbreak of Zika Virus Infection, Chiapas State, Mexico, 2015, and First Confirmed Transmission by Aedes aegypti Mosquitoes in the Americas.

BACKGROUND: After decades of obscurity, Zika virus (ZIKV) has spread through the Americas since 2015 accompanied by congenital microcephaly and Guillain-Barré syndrome. Although these epidemics presumably involve transmission by Aedes aegypti, no direct evidence of vector involvement has been reported, prompting speculation that other mosquitoes such as Culex quinquefasciatus could be involved. METHODS: We detected an outbreak of ZIKV infection in southern Mexico in late 2015. Sera from suspected ZIKV-infected patients were analyzed for viral RNA and antibodies. Mosquitoes were collected in and around patient homes and tested for ZIKV. RESULTS: Of 119 suspected ZIKV-infected patients, 25 (21%) were confirmed by RT-PCR of serum collected 1-8 days after the onset of signs and symptoms including rash, arthralgia, headache, pruritus, myalgia, and fever. Of 796 mosquitoes collected, A. aegypti yielded ZIKV detection by RT-PCR in 15 of 55 pools (27.3%). No ZIKV was detected in C. quinquefasciatus ZIKV sequences derived from sera and mosquitoes showed a monophyletic relationship suggestive of a point source introduction from Guatemala. CONCLUSIONS: These results demonstrate the continued, rapid northward progression of ZIKV into North America with typically mild disease manifestations, and implicate A. aegypti for the first time as a principal vector in North America.

Chikungunya Virus as Cause of Febrile Illness Outbreak, Chiapas, Mexico, 2014.

Since chikungunya virus (CHIKV) was introduced into the Americas in 2013, its geographic distribution has rapidly expanded. Of 119 serum samples collected in 2014 from febrile patients in southern Mexico, 79% were positive for CHIKV or IgM against CHIKV. Sequencing results confirmed CHIKV strains closely related to Caribbean isolates.

First Report of Aedes aegypti Transmission of Chikungunya Virus in the Americas.

During a chikungunya fever outbreak in late 2014 in Chiapas, Mexico, entomovirological surveillance was performed to incriminate the vector(s). In neighborhoods, 75 households with suspected cases were sampled for mosquitoes, of which 80% (60) harbored Aedes aegypti and 2.7% (2) Aedes albopictus. A total of 1,170 Ae. aegypti and three Ae. albopictus was collected and 81 pools were generated. Although none of the Ae. albopictus pools were chikungunya virus (CHIKV)-positive, 18 Ae. aegypti pools (22.8%) contained CHIKV, yielding an infection rate of 32.3/1,000 mosquitoes. A lack of herd immunity in conjunction with high mosquito populations, poor vector control services in this region, and targeted collections in locations of human cases may explain the high infection rate in this vector. Consistent with predictions from experimental studies, Ae. aegypti appears to be the principal vector of CHIKV in southern Mexico, while the role of Ae. albopictus remains unknown.

Mammalophilic feeding behaviour of Culex quinquefasciatus mosquitoes collected in the cities of Chetumal and Cancun, Yucatán Peninsula, Mexico.

OBJECTIVE: The studie describes the blood-feeding behaviour of mosquitoes in Mexico, to understand host-vector relationships and dynamics of disease transmission. METHODS: From September 2012 to November 2012 and in November 2013, 911 blood-fed Cx. quinquefasciatus mosquitoes were collected with aspirators inside houses in Chetumal and Cancun. Blood meals were analysed by PCR and subsequent Sanger sequencing of the cytochrome b gene. RESULTS: 93.3% of mosquitoes fed on mammals, 6.5% on birds and 0.2% on reptiles. The most frequent vertebrate hosts were humans (65.4%), dogs (23.2%), chicken (5.4%), cattle (2.2%) and cats (1.8%). CONCLUSIONS: Cx. quinquefasciatus most frequently fed on humans and dogs in both studied cities, which is in contrast to a previous study that demonstrated lower prevalence of mammalian blood in engorged Cx. quinquefasciatus.