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Brucellosis is a zoonosis mainly present in developing countries. The WHO reports 500,000 new cases every year. From 2012 to 2016, 13,677 cases were reported in Mexico, with 2.00 to 2.64 rate per 100,000 inhabitants. To analyze the diagnostic algorithm of brucellosis in Mexico, we compared the commercial laboratory tests ELISA, Brucellacapt®, and lateral flow test (LFT) in a study of 473 individuals from two endemic Mexican populations. All patients were treated in first-level medical units for presenting brucellosis compatible symptoms and without a history of the disease. Clinical-epidemiological information was gathered and initial serum samples were obtained to react with anti-Brucella antibodies; subsequent samples were collected at follow-up treatment visits. Using the Rose Bengal screening, we found 165 negative samples and 308 positive reactive samples, of which 222 cases were confirmed and 234 were positive on at least one marker (IgG or IgM) or LFT. When Brucellacapt® was used, similar results to those observed with the conventional algorithm were found as judged by the Cohen's kappa coefficient (κ) (0.813, 95% CI 0.7788-0.8472). Similar κ indices between conventional algorithm and ELISA pair were found, 0.7038 (95% CI 0.6555-0.7521), representing high similarity between both groups of diagnosis. We conclude that conventional serodiagnoses, Brucellacapt® and LFT, presented inconclusive results and poor correlation between them. By contrast, ELISA test pair (IgG + IgM) presented high correlation with the conventional algorithm and greater capacity for correct positive and negative classification.

Summary Background Effective Aedes aegypti control is limited, in part, by the difficulty in achieving sufficient intervention coverage. To maximise the effect of vector control, areas with persistently high numbers of Aedes-borne disease cases could be identified and prioritised for preventive interventions. We aimed to identify persistent Aedes-borne disease hotspots in cities across southern Mexico. Methods In this spatial analysis, geocoded cases of dengue, chikungunya, and Zika from nine endemic Mexican cities were aggregated at the census-tract level. We included cities that were located in southern Mexico (the arbovirus endemic region of Mexico), with a high burden of dengue cases (ie, more than 5000 cases reported during a 10-year period), and listed as high priority for the Mexican dengue control and prevention programme. The Getis-Ord Gi*(d) statistic was applied to yearly slices of the dataset to identify spatial hotspots of each disease in each city. We used Kendall's W coefficient to quantify the agreement in the distribution of each virus. Findings 128 507 dengue, 4752 chikungunya and 25 755 Zika clinical cases were reported between Jan 1, 2008, and Dec 31, 2016. All cities showed evidence of transmission heterogeneity, with a mean of 17·6% (SD 4·7) of their total area identified as persistent disease hotspots. Hotspots accounted for 25·6% (SD 9·7; range 12·8–43·0) of the population and 32·1% (10·5; 19·6–50·5) of all Aedes-borne disease cases reported. We found an overlap between hotspots of 61·7% for dengue and Zika and 53·3% for dengue and chikungunya. Dengue hotspots in 2008–16 were significantly associated with dengue hotspots detected during 2017–20 in five of the nine cities. Heads of vector control confirmed hotspot areas as problem zones for arbovirus transmission. Interpretation This study provides evidence of the overlap of Aedes-borne diseases within geographical hotspots and a methodological framework for the stratification of arbovirus transmission risk within urban areas, which can guide the implementation of surveillance and vector control. Funding USAID, the US Centers for Disease Control and Prevention, the Canadian Institutes of Health Research, International Development Research Centre, Fondo Mixto CONACyT (Mexico)-Gobierno del Estado de Yucatan, and the US National Institutes of Health. Translation For the Spanish translation of the abstract see Supplementary Materials section.

Introduction. The present study evaluated the quality of medical care for patients diagnosed with diabetes mellitus (DM), hypertension (HBP), and both pathologies (DM+HBP) within a public health system in Mexico. Methods. 45,498 patients were included from 2012 to 2015. All information was taken from the electronic medical record database. Each patient record was compared against the standard to test the quality of medical care. Results. Glycemia with hypertension goals reached 29.6% in DM+HBP, 48.6% in DM, and 53.2% in HBP. The goals of serum lipids were reached by 3% in DM+HBP, 5% in DM, and 0.2% in HBP. Glycemia, hypertension, and LDL cholesterol reached 0.04%. 15% of patients had an undiagnosed disease. Clinical follow-up examinations reached 20% for foot examination and clinical eye examination. Specialty referrals reached 1% in angiology or cardiology. Conclusion. Goals for glycemic and hypertension reached 50% in the overall population, while serum lipids, clinical follow-up examinations, and referral to a specialist were deficient. Patients who had both diseases had more consultations, better control for hypertension and lipids, but inferior glycemic control. Overall, quality care for DM and/or HBP has not been met according to the standards.

In Mexico, mosquito vector-borne diseases are of public health concern as a result of their impact on human morbidity and mortality. The use of insecticides against adult mosquitoes is one of the most common ways of controlling mosquito population densities. However, the use of these compounds has resulted in the development of insecticide resistance. The aim of this study was to estimate susceptibility to six pyrethroids, two carbamates and two organophosphates in Mexican populations of Stegomyia aegypti (Linnaeus, 1762) (= Aedes aegypti) (Diptera: Culicidae) mosquitoes. Bottle insecticide susceptibility tests, with 1 h exposure, were performed on adult mosquitoes from 75 localities across 28 states. At 30 min of exposure, the proportion of fallen mosquitoes was recorded. After 60 min of exposure, mosquitoes were recovered in non-treated containers and mortality was determined at 24 h after the set-up of the experiment. In general, the carbamate insecticides represented the most effective group in terms of the proportion of mosquitoes fallen at 30 min (72-100%) and 24-h mortality (97-100%). High and widespread resistance to pyrethroids Types I and II and, to a lesser extent, to organophosphates was observed. Insecticide susceptibility among and within states was highly variable.

In Mexico, the use of repellents to prevent insects from landing and biting is a common practice. However, variation in the efficiency of natural and synthetic repellents has been observed. In this study, we evaluated the repellency and protection time of 16 synthetic and 13 natural-based commercial products against Aedes aegypti (L.) from an endemic dengue area (Jojutla, Morelos) in Central Mexico. The "arm exposure" cage test was used to assess the efficacy of the repellents. Tests were conducted by three adult volunteers. Results showed that DEET (N, N-Diethyl-3-methylbenzamide) repellents provided the highest protection and duration times against Ae. aegypti. However, low repellency and short-time protection was observed (when compared with the manufacturers' protection times). Natural-based products did not repel (either landing or biting) mosquitoes for >30 min. These results show that most of the repellent products did not provide satisfactory levels of personal protection against mosquito bites. Frequent reapplication of repellents (synthetic and natural-based) may compensate for their short duration of action. Repellent efficacy data must be integrated into the decision-making process for an optimal response to the local (or specific region) situation.

espanolLa enfermedad de Chagas, causada por el Trypanosoma cruzi, esta considerada como la parasitosis mas grave en America. Se transmite principalmente por triatominos (chinches). El doctor Mazzoti reporto los dos primeros casos humanos en Mexico. La forma de transmision es por la entrada al organismo de los parasitos en heces del insecto, por transfusion sanguinea, de madre a hijo, por trasplante de organos y por accidentes de laboratorio. En Mexico se estima que 1.1 millones de personas estan infectadas; la incidencia en 2012 fue de 0.70 por 100 000 habitantes. En 2017, las mayores tasas de incidencia se registraron en Yucatan, Oaxaca e Hidalgo. La infeccion ocasiona miocardiopatias y megaorganos del tracto digestivo. El diagnostico en fase aguda es por abordaje parasitologico y en fase cronica, por estudios de tamizaje por laboratorio. En los bancos de sangre de Mexico, el estudio de la enfermedad de Chagas es de observancia obligatoria; de 2007 a 2016, la seroprevalencia ha disminuido de 0.40 a 0.32 debido a la mejora de los procesos de seleccion al donante y al cuestionario ad hoc. Los blancos del parasito son las celulas neuronales y las de los musculos liso y miocardico. La asociacion de la destruccion neuronal y del musculo liso define la presentacion de los sindromes megachagasicos. Las manifestaciones iniciales de la enfermedad pueden pasar desapercibidas; 5 % de los pacientes presenta signos y sintomas aparentes y 30 % evolucionara a la fase cronica asintomatica. Los tratamientos actuales tienen efecto en la fase aguda. Para el control de la enfermedad de Chagas se dispone del Programa de Accion Especifico para la Vigilancia Prevencion y Control de la Enfermedad de Chagas (PAE Chagas 2013-2018), encaminado a eliminar la transmision transfusional y congenita y a controlar la transmision vectorial. De la deteccion oportuna, el tratamiento etiologico temprano y la ampliacion de cobertura depende el exito de la atencion medica. Por su parte, la vigilancia y tamizaje de las mujeres embarazadas que viven en zonas de riesgo y el tamizaje universal de donadores de sangre y organos haran posible la eliminacion de la transmision connatal y transfusional. EnglishChagas disease, which is caused by Trypanosoma cruzi, is considered to be the most serious parasitic disease in America. It is transmitted mainly by triatominae (“kissing bugs”). Mazzoti reported the first two human cases in Mexico. The form of transmission is by parasites entering the organism in feces of the insect, by blood transfusion, from mother to child, by organ transplant and laboratory accidents. In Mexico, 1.1 million people are estimated to be infected; the incidence in 2012 was 0.70 per 1,00,000 population. In 2017, the highest incidence rates were registered in Yucatan, Oaxaca and Hidalgo. The infection causes cardiomyopathies and mega-organs of the digestive tract. Diagnosis in the acute phase is by parasitological approach and, in the chronic phase, by laboratory screening studies. In Mexico’s blood banks, screening for Chagas disease is mandatory; from 2007 to 2016, seroprevalence has decreased from 0.40 to 0.32 due to the improvement of donor selection processes and the ad hoc questionnaire. The targets of the parasite are neurons and smooth and myocardial muscle cells. The association of neuronal and smooth muscle destruction defines the presentation of chagas mega-syndromes. Initial manifestations of the disease can go unnoticed; 5% show apparent signs and symptoms and 30% will progress to the chronic asymptomatic phase. Currently available treatments have effect in the acute phase. For the control of Chagas disease, the Specific Action Program for the Prevention and Control of Chagas Disease (PAE Chagas 2013-2018) is available to initiate activities aimed at eliminating transfusion and congenital transmission and controlling vector transmission. The success of medical care depends on oportune detection, early etiological treatment and coverage broadening. On the other hand, monitoring and screening of pregnant women living in risk areas and blood and organ donors universal screening will enable the elimination congenital and transfusion transmission.

Response to Zika virus (ZIKV) invasion in Brazil lagged a year from its estimated February 2014 introduction, and was triggered by the occurrence of severe congenital malformations. Dengue (DENV) and chikungunya (CHIKV) invasions tend to show similar response lags. We analyzed geo-coded symptomatic case reports from the city of Merida, Mexico, with the goal of assessing the utility of historical DENV data to infer CHIKV and ZIKV introduction and propagation. About 42% of the 40,028 DENV cases reported during 2008–2015 clustered in 27% of the city, and these clustering areas were where the first CHIKV and ZIKV cases were reported in 2015 and 2016, respectively. Furthermore, the three viruses had significant agreement in their spatio-temporal distribution (Kendall W>0.63; p, Author summary Over the past decades, Aedes-borne viruses (dengue, chikungunya, Zika) have become a major source of morbidity within urban areas. Worldwide, public health response to these viruses is reactive to the occurrence of symptomatic cases (a small proportion of all infections). Here we used geocoded passive surveillance data to determine if areas of historically persistent dengue transmission fuel the introduction and propagation of other Aedes-borne viruses. This article provides quantitative evidence of the strong spatio-temporal overlap that occurs between dengue, chikungunya and Zika, all transmitted by Aedes aegypti mosquitoes in the city. Additionally, it emphasizes the value of analyzing long-term geo-coded passive surveillance information to help identify areas for prioritizing surveillance and control. Findings from this article open a window for considering historical DENV data to make predictions of likely sources of invasion for other emerging Aedes-borne viruses, as well as to the consideration of spatially-targeted approaches for delivery of vector control and surveillance. Arbovirus control in complex urban environments can greatly benefit from exploiting existing spatial information for better delivery of interventions.

Stegomyia aegypti (= Aedes aegypti) (Diptera: Culicidae) is a species of mosquito that is currently widespread in Mexico. Historically, the mosquito has been distributed across most tropical and subtropical areas lower than 1700 m a.s.l. Currently, populations that are found at higher altitudes in regions with cold and dry climates suggest that these conditions do not limit the colonization and population growth of S. aegypti. During a survey of mosquitoes in September 2015, larvae of S. aegypti mosquitoes were found in two different localities in Mexico City, which is located at about 2250 m a.s.l. Mexico City is the most populous city in Mexico and has inefficient drainage and water supply systems. These factors may result in the provision of numerous larval breeding sites. Mosquito monitoring and surveillance are now priorities for the city.

In Mexico, Aedes aegypti (L.) (Diptera: Culicidae) is the primary vector of Dengue, Zika, and Chikungunya viruses. Control programs include community participation using personal protection such as household aerosol insecticides. In both, urban or rural areas, the use of aerosol insecticides is a common practice to avoiding mosquito biting. Thus, information on the efficacy of commercial products must be available. This study reports the efficacy of 13 household aerosol insecticides against Ae. aegypti from an endemic dengue area in Mexico. To test each insecticide, six netting cages, containing 10 non-blood fed female mosquitoes each one, were placed in different locations inside a bedroom. Readings at 30 min and 24 h after exposure were recorded. No products showed 100% mortality after 30 min of exposure. Only three products killed the 100% of the individuals 24 h after exposure. Results showed a high mortality variance among insecticides. Location in the room also impacts the insecticide efficacy. Mosquitoes located inside cabinets or with behind an obstacle (preventing an accurate insecticide exposure) showed lower mortalities. Products and spraying methods could and should be improved.

Background We report on the results of an entomovirological surveillance system of Aedes populations performed by the Ministry of Health of the central state of San Luis Potosi, Mexico. Methods Indoor adult Aedes aegypti and Aedes albopictus pools collected at San Martin, Tamazunchale, Ciudad Valles, Metlapa, Ebano, Tamuin and Axtla during the dry season of 2016 were examined for the presence of dengue (DENV), chikungunya (CHIKV) and Zika (ZIKV) viruses using real-time PCR. Results Both Ae. aegypti and Ae. albopictus were found to be infected with ZIKV in the absence of confirmed symptomatic human cases. Conclusions The entomovirological surveillance system analysed here identified both Ae. aegypti and Ae. albopictus infected with ZIKV which triggered an immediate aggressive vector control campaign.

Tobacco use is a worldwide public health problem. According to the World Health Organization (WHO), smoking is the second principal cause of death in the world, with almost five million deaths annually. Information about tobacco consumption is essential in order to improve the focus of prevention and control measures and thereby succeed in the struggle against tobacco use. This literature review, carried out in Mexico in 2006, presents a comparative analysis of information about smoking prevalence from the National Addictions Survey 2002, as it relates to results obtained in previous surveys. This review also presents information about youth and passive smoking, tobacco consumption in the medical profession and impact on mortality as aspects relevant to the analysis of this epidemic. Epidemiological information is viewed in the context of the tobacco use component of the Plan of Action on Addiction and the WHO Framework Convention on Tobacco Control.

En Mexico y otros paises, la accesibilidad que tienen los menores de edad a productos derivados del tabaco -sobre todo cigarros- es un factor primordial que contribuye al desarrollo del tabaquismo, que hoy dia constituye uno de los principales desafios de la salud publica en todo el mundo. En la lucha contra esta adiccion, la existencia de una legislacion eficaz para disminuir la produccion, distribucion y venta de productos derivados del tabaco es indispensable para crear las condiciones necesarias y lograr una sociedad libre de tabaco. La venta de cigarros a menores es un acto que posee caracteristicas especificas en cada lugar y tiempo en que se evalua. En particular, en el Distrito Federal la falta de vigilancia en el cumplimiento de las disposiciones oficiales contribuye a que los menores de edad consigan los cigarros en la mayoria de los comercios y los adquieran de forma directa.

BackgroundRecently, the World Health Organisation and the International Union Against Tuberculosis and Lung Disease published a Collaborative Framework for the Care and Control of Tuberculosis (TB) and Diabetes (DM) (CFTB/DM) proposing bidirectional screening and joint management.ObjectiveTo evaluate the feasibility and effectiveness of the CFTB/DM in Mexico.DesignProspective observational cohort.Setting15 primary care units in 5 states in Mexico.ParticipantsPatients aged ≥20 years diagnosed with DM or pulmonary TB who sought care at participating clinics.InterventionThe WHO/Union CFTB/DM was adapted and implemented according to official Mexican guidelines. We recruited participants from July 2012 to April 2013 and followed up until March 2014. Bidirectional screening was performed. Patients diagnosed with TB and DM were invited to receive TB treatment under joint management.Main outcome measuresDiagnoses of TB among DM, of DM among TB, and treatment outcomes among patients with DM and TB.ResultsOf 783 DM patients, 11 (1.4%) were unaware of their TB. Of 361 TB patients, 16 (4.4%) were unaware of their DM. 95 TB/DM patients accepted to be treated under joint management, of whom 85 (89.5%) successfully completed treatment. Multiple linear regression analysis with change in HbA1c and random capillary glucose as dependent variables revealed significant decrease with time (regression coefficients (β) = -0.660, (95% confidence interval (CI), -0.96 to -0.35); and β = -1.889 (95% CI, -2.77 to -1.01, respectively)) adjusting by sex, age and having been treated for a previous TB episode. Patients treated under joint management were more likely to experience treatment success than patients treated under routine DM and TB programs as compared to historical (adjusted OR (aOR), 2.8, 95%CI 1.28-6.13) and same period (aOR 2.37, 95% CI 1.13-4.96) comparison groups.ConclusionsJoint management of TB and DM is feasible and appears to improve clinical outcomes.

We identified 2 poultry workers with conjunctivitis caused by highly pathogenic avian influenza A(H7N3) viruses in Jalisco, Mexico. Genomic and antigenic analyses of 1 isolate indicated relatedness to poultry and wild bird subtype H7N3 viruses from North America. This isolate had a multibasic cleavage site that might have been derived from recombination with host rRNA.

In Mexico and other countries, the accessibility that minors have to products derived from tobacco -mainly cigarettes- is a primary contributing factor to smoking, and is currently one of the main public health challenges worldwide. In the fight against tobacco use, effective legislation for decreasing production, distribution and the sale of tobacco products is indispensable to the creation of conditions necessary for achieving a tobacco-free society. The sale of cigarettes to minors is an act that has unique characteristics according to the particular location, particularly in Mexico City, and the time in which it is evaluated. The lack of monitoring compliance with official regulations contributes to the fact that minors directly obtain cigarettes from most of the stores.

Tobacco use is a worldwide public health problem. According to the World Health Organization (WHO), smoking is the second principal cause of death in the world, with almost five million deaths annually. Information about tobacco consumption is essential in order to improve the focus of prevention and control measures and thereby succeed in the struggle against tobacco use. This literature review, carried out in Mexico in 2006, presents a comparative analysis of information about smoking prevalence from the National Addictions Survey 2002, as it relates to results obtained in previous surveys. This review also presents information about youth and passive smoking, tobacco consumption in the medical profession and impact on mortality as aspects relevant to the analysis of this epidemic. Epidemiological information is viewed in the context of the tobacco use component of the Plan of Action on Addiction and the WHO Framework Convention on Tobacco Control.

Background Mexico is one of the six countries formerly endemic for onchocerciasis in Latin America. Transmission has been interrupted in the three endemic foci of that country and mass drug distribution has ceased. Three years after mass drug distribution ended, post-treatment surveillance (PTS) surveys were undertaken which employed entomological indicators to check for transmission recrudescence. Methodology/Principal findings In-depth entomologic assessments were performed in 18 communities in the three endemic foci of Mexico. None of the 108,212 Simulium ochraceum s.l. collected from the three foci were found to contain parasite DNA when tested by polymerase chain reaction-enzyme-linked immunosorbent assay (PCR-ELISA), resulting in a maximum upper bound of the 95% confidence interval (95%-ULCI) of the infective rate in the vectors of 0.035/2,000 flies examined. This is an order of magnitude below the threshold of a 95%-ULCI of less than one infective fly per 2,000 flies tested, the current entomological criterion for interruption of transmission developed by the international community. The point estimate of seasonal transmission potential (STP) was zero, and the upper bound of the 95% confidence interval for the STP ranged from 1.2 to 1.7 L3/person/season in the different foci. This value is below all previous estimates for the minimum transmission potential required to maintain the parasite population. Conclusions/Significance The results from the in-depth entomological post treatment surveillance surveys strongly suggest that transmission has not resumed in the three foci of Mexico during the three years since the last distribution of ivermectin occurred; it was concluded that transmission remains undetectable without intervention, and Onchocerca volvulus has been eliminated from Mexico., Author Summary Onchocerciasis, or river blindness, is one of the neglected tropical diseases targeted by the international community for elimination. In Mexico, onchocerciasis was historically endemic in three foci, which included Northern Chiapias, Southern Chiapas and Oaxaca. Both the criteria for verification of elimination and for post-treatment surveillance developed by the international community rely heavily on the use of entomological metrics. The absence of evidence of ongoing transmission of the parasite three years after mass drug distribution has been halted is considered to be evidence that elimination efforts have been successful. In the present study, we report entomological assessments carried out in the three endemic foci in Mexico that were performed three years following the end of mass drug distribution in each focus. None of the over 100,000 Simulium ochraceum s.l. vector black flies collected from sentinel and extra-sentinel communities in these foci were found to contain parasite DNA, suggesting vector parasite contact was non-existent. This data suggest that elimination of onchocerciasis from Mexico has been achieved.