Detection of IgG antibodies against the receptor binding domain of the spike protein and nucleocapsid of SARS-CoV-2 at university students from Southern Mexico: a cross-sectional study.

BACKGROUND: Natural infection and vaccination against SARS-CoV-2 is associated with the development of immunity against the structural proteins of the virus. Specifically, the two most immunogenic are the S (spike) and N (nucleocapsid) proteins. Seroprevalence studies performed in university students provide information to estimate the number of infected patients (symptomatic or asymptomatic) and generate knowledge about the viral spread, vaccine efficacy, and epidemiological control. Which, the aim of this study was to evaluate IgG antibodies against the S and N proteins of SARS-CoV-2 at university students from Southern Mexico. METHODS: A total of 1418 serum samples were collected from eighteen work centers of the Autonomous University of Guerrero. Antibodies were detected by Indirect ELISA using as antigen peptides derived from the S and N proteins. RESULTS: We reported a total seroprevalence of 39.9% anti-S/N (positive to both antigens), 14.1% anti-S and 0.5% anti-N. The highest seroprevalence was reported in the work centers from Costa Grande, Acapulco and Centro. Seroprevalence was associated with age, COVID-19, contact with infected patients, and vaccination. CONCLUSION: University students could play an essential role in disseminating SARS-CoV-2. We reported a seroprevalence of 54.5% against the S and N proteins, which could be due to the high population rate and cultural resistance to safety measures against COVID-19 in the different regions of the state.

The influence of gender and temephos exposure on community participation in dengue prevention: a compartmental mathematical model.

BACKGROUND: The use of temephos, the most common intervention for the chemical control of Aedes aegypti over the last half century, has disappointing results in control of the infection. The footprint of Aedes and the diseases it carries have spread relentlessly despite massive volumes of temephos. Recent advances in community participation show this might be more effective and sustainable for the control of the dengue vector. METHODS: Using data from the Camino Verde cluster randomized controlled trial, a compartmental mathematical model examines the dynamics of dengue infection with different levels of community participation, taking account of gender of respondent and exposure to temephos. RESULTS: Simulation of dengue endemicity showed community participation affected the basic reproductive number of infected people. The greatest short-term effect, in terms of people infected with the virus, was the combination of temephos intervention and community participation. There was no evidence of a protective effect of temephos 220 days after the onset of the spread of dengue. CONCLUSIONS: Male responses about community participation did not significantly affect modelled numbers of infected people and infectious mosquitoes. Our model suggests that, in the long term, community participation alone may have the best results. Adding temephos to community participation does not improve the effect of community participation alone.

Social capital is associated with lower mosquito vector indices: secondary analysis from a cluster randomised controlled trial of community mobilisation for dengue prevention in Mexico.

BACKGROUND: Control of the Aedes aegypti mosquito is central to reducing the risk of dengue, zika, chikungunya, and yellow fever. Randomised controlled trials, including the Camino Verde trial in Mexico and Nicaragua, demonstrate the convincing impact of community mobilisation interventions on vector indices. These interventions might work through building social capital but little is known about the relationship between social capital and vector indices. METHODS: A secondary analysis used data collected from 45 intervention clusters and 45 control clusters in the impact survey of the Mexican arm of the Camino Verde cluster randomised controlled trial. Factor analysis combined responses to questions about aspects of social capital to create a social capital index with four constructs, their weighted averages then combined into a single scale. We categorised households as having high or low social capital based on their score on this scale. We examined associations between social capital and larval and pupal vector indices, taking account of the effects of other variables in a multivariate analysis. We report associations as odds ratios and 95% confidence intervals. RESULTS: The four social capital constructs were involvement, participation, investment, and communication. Among the 10,112 households, those in rural communities were much more likely to have a high social capital score (OR 4.51, 95% CIca 3.26-6.26). Households in intervention sites had higher social capital, although the association was not significant at the 5% level. Households with high social capital were more likely to be negative for larvae or pupae (OR 1.38, 95% CIca 1.12-1.69) and for pupae specifically (OR 1.37, 95% CIca 1.08-1.74). There was interaction between intervention status and social capital; in multivariate analysis, a combined variable of intervention/high social capital remained associated with larvae or pupae (ORa l.56, 95% CIca 1.19-2.04) and with pupae specifically (ORa 1.65, 95% CIca 1.20-2.28). CONCLUSION: This is the first report of an association of high social capital with low vector indices. Our findings support the idea that the Camino Verde community mobilisation intervention worked partly through an interaction with social capital. Understanding such interactions may help to maximise the impact of future community mobilisation interventions.

Assessing the effects of interventions for Aedes aegypti control: systematic review and meta-analysis of cluster randomised controlled trials.

BACKGROUND: The Aedes aegypti mosquito is the vector for dengue fever, yellow fever, chikungunya, and zika viruses. Inadequate vector control has contributed to persistence and increase of these diseases. This review assesses the evidence of effectiveness of different control measures in reducing Aedes aegypti proliferation, using standard entomological indices. METHODS: A systematic search of Medline, Ovid, BVS, LILACS, ARTEMISA, IMBIOMED and MEDIGRAPHIC databases identified cluster randomised controlled trials (CRCTs) of interventions to control Aedes aegypti published between January 2003 and October 2016. Eligible studies were CRCTs of chemical or biological control measures, or community mobilization, with entomological indices as an endpoint. A meta-analysis of eligible studies, using a random effects model, assessed the impact on household index (HI), container index (CI), and Breteau index (BI). RESULTS: From 848 papers identified by the search, eighteen met the inclusion criteria: eight for chemical control, one for biological control and nine for community mobilisation. Seven of the nine CRCTs of community mobilisation reported significantly lower entomological indices in intervention than control clusters; findings from the eight CRCTs of chemical control were more mixed. The CRCT of biological control reported a significant impact on the pupae per person index only. Ten papers provided enough detail for meta-analysis. Community mobilisation (four studies) was consistently effective, with an overall intervention effectiveness estimate of -0.10 (95%CI -0.20 - 0.00) for HI, -0.03 (95%CI -0.05 - -0.01) for CI, and -0.13 (95%CI -0.22 - -0.05) for BI. The single CRCT of biological control had effectiveness of -0.02 (95%CI -0.07- 0.03) for HI, -0.02 (95%CI -0.04- -0.01) for CI and -0.08 (95%CI -0.15- -0.01) for BI. The five studies of chemical control did not show a significant impact on indices: the overall effectiveness was -0.01 (95%CI -0.05- 0.03) for HI, 0.01 (95% CI -0.01- 0.02) for CI, and 0.01 (95%CI -0.03 - 0.05) for BI. CONCLUSION: Governments that rely on chemical control of Aedes aegypti should consider adding community mobilization to their prevention efforts. More well-conducted CRCTs of complex interventions, including those with biological control, are needed to provide evidence of real life impact. Trials of all interventions should measure impact on dengue risk.

"Where we put little fish in the water there are no mosquitoes:" a cross-sectional study on biological control of the Aedes aegypti vector in 90 coastal-region communities of Guerrero, Mexico.

BACKGROUND: In the Mexican state of Guerrero, some households place fish in water storage containers to prevent the development of mosquito larvae. Studies have shown that larvivorous fish reduce larva count in household water containers, but there is a lack of evidence about whether the use of fish is associated with a reduction in dengue virus infection. We used data from the follow up survey of the Camino Verde cluster randomised controlled trial of community mobilisation to reduce dengue risk to study this association. METHODS: The survey in 2012, among 90 clusters in the three coastal regions of Guerrero State, included a questionnaire to 10,864 households about socio-demographic factors and self-reported cases of dengue illness in the previous year. Paired saliva samples provided serological evidence of recent dengue infection among 4856 children aged 3-9 years. An entomological survey in the same households looked for larvae and pupae of Aedes aegypti and recorded presence of fish and temephos in water containers. We examined associations with the two outcomes of recent dengue infection and reported dengue illness in bivariate analysis and then multivariate analysis using generalized linear mixed modelling. RESULTS: Some 17% (1730/10,111) of households had fish in their water containers. The presence of fish was associated with lower levels of recent dengue virus infection in children aged 3-9 years (OR 0.64; 95% CI 0.45-0.91), as was living in a rural area (OR 0.57; 95% CI 0.45-0.71), and being aged 3-5 years (OR 0.65; 95% CI 0.51-0.83). Factors associated with lower likelihood of self-reported dengue illness were: the presence of fish (OR 0.79; 95% CI 0.64-0.97), and living in a rural area (OR 0.74; 95% CI 0.65-0.84). Factors associated with higher likelihood of self-reported dengue illness were: higher education level of the household head (OR 1.28; 95% CI 1.07-1.52), living in a household with five people or less (OR 1.33; 95% CI 1.16-1.52) and household use of insecticide anti-mosquito products (OR 1.68; 95% CI 1.47-1.92). CONCLUSIONS: Our study suggests that fish in water containers may reduce the risk of dengue virus infection and dengue illness. This could be a useful part of interventions to control the Aedes aegypti vector.

Helicobacter pylori Virulence Factors and Clarithromycin Resistance-Associated Mutations in Mexican Patients.

Persistent infection with Helicobacter pylori (H. pylori) is an important factor in gastric diseases. The vacA and cagA virulence factors of H. pylori contribute to the development of these diseases. Triple therapy containing clarithromycin has been used to eradicate this infection. Unfortunately, resistance to this antibiotic is the primary cause of treatment failure. This study aimed to determine the prevalence of clarithromycin resistance-associated mutations and to assess the relationship between virulence factors and Mexican patients infected with H. pylori. The cagA and vacA genotypes were determined by multiplex PCR. Furthermore, a qPCR was used to identify mutations of the 23S rRNA gene. This study reported a prevalence of 84.3% of H. pylori among patients with gastric diseases, and the vacA s1m1/cagA+ genotype was the most frequent (44.8%) in antrum and corpus. Analysis of the 23S rRNA gene revealed a 19.8% prevalence of clarithromycin resistance-associated mutations. The most prevalent mutations were A2143G (56%) and A2142C (25%). A significant association (p < 0.05) between the A2142G and the vacA s1m1/cagA+ genotype was detected. In conclusion, we report a high prevalence (>15%) of clarithromycin resistance-associated mutations, and we found an association between the genotypes of virulence factors and a mutation in the 23S rRNA gene.

Combined Inhibition of Indolamine-2,3-Dioxygenase 1 and C-X-C Chemokine Receptor Type 2 Exerts Antitumor Effects in a Preclinical Model of Cervical Cancer.

Cervical cancer is a public health problem diagnosed in advanced stages, and its main risk factor is persistent high-risk human papillomavirus infection. Today, it is necessary to study new treatment strategies, such as immunotherapy, that use different targets of the tumor microenvironment. In this study, the K14E7E2 mouse was used as a cervical cancer model to evaluate the inhibition of indolamine-2,3-dioxygenase 1 (IDO-1) and C-X-C chemokine receptor type 2 (CXCR-2) as potential anti-tumor targets. DL-1MT and SB225002 were administered for 30 days in two regimens (R1 and R2) based on combination and single therapy approaches to inhibit IDO-1 and CXCR-2, respectively. Subsequently, the reproductive tracts were resected and analyzed to determine the tumor areas, and IHCs were performed to assess proliferation, apoptosis, and CD8 cellular infiltration. Our results revealed that combined inhibition of IDO-1 and CXCR-2 significantly reduces the areas of cervical tumors (from 196.0 mm2 to 58.24 mm2 in R1 and 149.6 mm2 to 52.65 mm2 in R2), accompanied by regions of moderate dysplasia, decreased papillae, and reduced inflammation. Furthermore, the proliferation diminished, and apoptosis and intra-tumoral CD8 T cells increased. In conclusion, the combined inhibition of IDO-1 and CXCR-2 is helpful in the antitumor response against preclinical cervical cancer.

Utility of a Pulmonary Oedema Score for Predicting the Need for Mechanical Ventilation in COVID-19 Patients in a General Hospital.

BACKGROUND: The Radiographic Assessment of Lung Edema (RALE) score has been used to estimate the extent of pulmonary damage in patients with acute respiratory distress syndrome and might be useful in patients with COVID-19. AIM OF THE STUDY: To examine factors associated with the need for mechanical ventilation in hospitalized patients with a clinical diagnosis of COVID-19, and to estimate the predictive value of the RALE score. METHODS: In a series of patients admitted between April 14 and August 28, 2020, with a clinical diagnosis of COVID-19, we assessed lung involvement on the chest radiograph using the RALE score. We examined factors associated with the need for mechanical ventilation in bivariate and multivariate analysis. The area under the receiver operating curve (AUC) indicated the predictive value of the RALE score for need for mechanical ventilation. RESULTS: Among 189 patients, 90 (48%) were judged to need mechanical ventilation, although only 60 were placed on a ventilator. The factors associated with the need for mechanical ventilation were a RALE score >6 points, age >50 years, and presence of chronic kidney disease. The AUC for the RALE score was 60.9% (95% CI 52.9-68.9), indicating it was an acceptable predictor of needing mechanical ventilation. CONCLUSIONS: A score for extent of pulmonary oedema on the plain chest radiograph was a useful predictor of the need for mechanical ventilation of hospitalized patients with COVID-19.

Utility of entomological indices for predicting transmission of dengue virus: secondary analysis of data from the Camino Verde trial in Mexico and Nicaragua.

Dengue vector entomological indices are widely used to monitor vector density and disease control activities. But the value of these indices as predictors of dengue infection is not established. We used data from the impact assessment of a trial of community mobilization for dengue prevention (Camino Verde) to examine the associations between vector indices and evidence of dengue infection and their value for predicting dengue infection levels. In 150 clusters in Mexico and Nicaragua, two entomological surveys, three months apart, allowed calculation of the mean Container Index, Breteau index, Pupae per Household Index, and Pupae per Container Index across the two surveys. We measured recent dengue virus infection in children, indicated by a doubling of dengue antibodies in paired saliva samples over the three-month period. We examined the associations between each of the vector indices and evidence of dengue infection at household level and at cluster level, accounting for trial intervention status. To examine the predictive value for dengue infection, we constructed receiver operating characteristic (ROC) curves at household and cluster level, considering the four vector indices as continuous variables, and calculated the positive and negative likelihood ratios for different levels of the indices. None of the vector indices was associated with recent dengue infection at household level. The Breteau Index was associated with recent infection at cluster level (Odds ratio 1.36, 95% confidence interval 1.14-1.61). The ROC curve confirmed the weak predictive value for dengue infection of the Breteau Index at cluster level. Other indices showed no predictive value. Conventional vector indices were not useful in predicting dengue infection in Mexico and Nicaragua. The findings are compatible with the idea of sources of infection outside the household which were tackled by community action in the Camino Verde trial.

Perceived stress in dental students of a private university in Acapulco, Mexico / Estrés percibido en estudiantes de Odontología de una universidad privada de Acapulco, México / Estresse percebido em estudantes de odontologia de uma universidade particular em Acapulco, México

ABSTRACT Stress is a common aspect of daily life, but its negative impact emerges when it disrupts normal daily functioning. It triggers physiological changes within the body's systems, influencing behavior and emotions. Objective: This study aims to assess the frequency of perceived stress among dental students attending a private institute in Acapulco, Guerrero, Mexico. Material and methods: A descriptive cross-sectional study was conducted in November 2020. The survey targeted seventy-one Dentistry students ranging from the first to seventh semester. The survey collected sociodemographic information and utilized the ten-item Perceived Stress Scale, developed by Cohen, which employs a Likert-type scale with five categorical values. The scores were analyzed using the R statistical program. Simple frequencies of variables were obtained, and Student's t-test was employed to compare students' stress levels. The odds ratio (OR), along with its 95 % confidence interval (CI 95%) using the Miettinen method, was calculated to quantify stress risk based on gender and semester. Results: Among the participants, 60 % (43/71) experienced high levels of stress. Specifically, female students accounted for a higher occurrence of stress at 70 % (30/43). The association of high stress was particularly prominent among students in the last semester (OR = 2.88; 95 % CI = 1.07-7.71). Conclusion: The findings suggest that a significant portion, at least six out of ten students, experience elevated stress levels. The study underscores the importance of dental educators identifying and addressing stressful situations among students, thereby facilitating the referral of cases in need of psychological support.

RESUMEN El estrés es una situación cotidiana normal, pero tiene repercusiones negativas cuando altera el funcionamiento diario en la vida humana. Implica cambios en los sistemas fisiológicos corporales del organismo, los cuales influyen en el comportamiento y los sentimientos. Objetivo: Estimar la frecuencia del estrés percibido en estudiantes de Odontología de un instituto privado de Acapulco, Guerrero, México. Material y métodos: Estudio transversal descriptivo realizado en noviembre de 2020. Se encuestaron a 71 estudiantes de primero a séptimo semestre de Odontología. El instrumento de medición obtuvo datos sociodemográficos y se utilizó la Escala de Estrés Percibido de diez ítems, propuesta por Cohen, la cual toma un escalamiento tipo Likert de cinco valores categoriales. Las puntuaciones fueron analizadas a través del programa estadístico de R, que obtuvo frecuencias simples de las variables, y se utilizó la prueba t de Student para comparar los niveles de estrés en los estudiantes. Fue estimada la razón de momios (RM) con su intervalo de confianza de Miettinen del 95 % (IC 95%) para cuantificar el nivel de riesgo del estrés, por género y semestre. Resultados: El 60 % (43/71) de los estudiantes presentó estrés alto. Respecto al sexo, las mujeres presentaron mayor ocurrencia del fenómeno con el 70 % (30/43). La fuerza de asociación del estrés alto se presentó en los estudiantes del último semestre (OR = 2,88; IC 95 % = 1,07-7,71). Conclusión: Al menos seis de cada diez estudiantes presentaron variaciones de estrés alto. Se sugiere que los educadores de odontología identifiquen las situaciones de estrés en los estudiantes con el fin de derivar los casos que requieren ayuda psicológica.

RESUMO O estresse é uma ocorrência comum no cotidiano, mas suas implicações negativas surgem quando afeta o funcionamento diário das vidas humanas. Isso envolve alterações nos sistemas fisiológicos do corpo, influenciando comportamentos e sentimentos. Objetivo: Estimar a frequência do estresse percebido entre estudantes de odontologia de uma instituição privada em Acapulco, Guerrero, México. Material e métodos: Realizou-se um estudo descritivo de corte transversal em novembro de 2020. Um total de 71 estudantes de Odontologia, do primeiro ao sétimo semestre, foram incluídos na pesquisa. O instrumento de medição coletou informações sociodemográficas e empregou a Escala de Estresse Percebido de dez itens, proposta por Cohen, utilizando uma escala Likert de cinco categorias. As pontuações foram analisadas através do software estatístico R, gerando frequências simples das variáveis e aplicando o teste t de Student para comparar o nível de estresse entre os alunos. A Razão de Chances (RC) com um intervalo de confiança de Miettinen de 95% (IC 95%) foi calculada para quantificar o risco de estresse por gênero e semestre. Resultados: Dos estudantes, 60% (43/71) apresentaram alto nível de estresse. No que se refere ao gênero, as mulheres tiveram uma maior incidência, com 70% (30/43). Observou-se uma associação significativa de alto estresse entre os alunos do último semestre (RC = 2,88, IC 95% = 1,07-7,71). Conclusão: Pelo menos seis em cada dez estudantes demonstraram níveis elevados de estresse. Recomenda-se que os educadores de Odontologia identifiquem situações estressantes nos alunos para encaminhar os casos que possam requerer apoio psicológico.

[Clinical profile of dengue and predictive severity variables among children at a secondary care hospital of Chilpancingo, Guerrero, Mexico: case series]. / Caracterización clínica del dengue y variables predictoras de gravedad en pacientes pediátricos en un hospital de segundo nivel en Chilpancingo, Guerrero, México: serie de casos.

BACKGROUND: Dengue continues to increase globally. Currently, the highest incidence of first infection occurs in paediatric population, where severe dengue fever is potentially lethal. This study characterizes the clinical profile of paediatric patients with dengue fever in the South of Mexico. METHODS: We undertook a series case study of 133 paediatric inpatients who presented clinical diagnosis of non-severe dengue and severe dengue fever. We described univariate analysis as means or percentages, using 0.05 as significance level. We estimated the prediction of severe dengue considering clinical signs and symptoms only using GLMM (Generalised Linear Mixed Models). RESULTS: 58% (77/133) patients had severe dengue. There were significant differences among the dengue groups, in the following signs and symptoms: Fever, abdominal pain, epistaxis and platelet count. Children older than four years old had a higher proportion of severe dengue (p<0.05). GLMM identified a group of four clinical signs and symptoms (fever ≥39°C, myalgia, arthralgia and abdominal pain) as predictors of severe dengue. CONCLUSIONS: The results of this exploratory study suggest changes in the frequency of clinical signs and symptoms among paediatric inpatients. Paediatric patients with a presumptive diagnosis of dengue, showing fever of ≥39° C, myalgia, arthralgia and abdominal pain should be considered as potential cases of severe dengue.

Caracterización clínica del dengue y variables predictoras de gravedad en pacientes pediátricos en un hospital de segundo nivel en Chilpancingo, Guerrero, México: serie de casos / Clinical profile of dengue and predictive severity variables among children at a secondary care hospital of Chilpancingo, Guerrero, Mexico: case series

Resumen: Introducción: El dengue sigue en incremento a nivel mundial y actualmente la mayor incidencia de primera infección ocurre en población pediátrica. El dengue grave es potencialmente letal en menores de edad. Este estudio caracteriza el perfil clínico de pacientes pediátricos con dengue atendidos en un hospital de segundo nivel en Chilpancingo, Guerrero, México. Métodos: Serie de casos conformada por 133 pacientes pediátricos hospitalizados con diagnóstico de dengue no grave y dengue grave, de acuerdo a criterios clínicos. Los resultados del análisis univariado de los signos y síntomas clínicos fueron expresados como promedios o porcentajes, y se consideró nivel de significancia estadística de 0.05. Mediante GLMM (Generalised Linear Mixed Models) se estimó la predicción de dengue grave con la presencia de signos y síntomas clínicos. Resultados: El 58% (77/133) de los pacientes fue clasificado como dengue grave. Hubo diferencias significativas entre los grupos de dengue en los signos y síntomas siguientes: fiebre, dolor abdominal, epistaxis y cuenta plaquetaria. El dengue grave se presentó en mayor proporción en los pacientes mayores de cuatro años de edad (p<0.05). El GLMM identificó un conjunto de cuatro signos y síntomas clínicos (fiebre ≥39 °C, mialgias, artralgias y dolor abdominal) como predictores de la gravedad del dengue. Conclusiones: Los resultados de este estudio exploratorio sugieren cambios en la frecuencia de síntomas y signos clínicos del dengue en la población pediátrica. Pacientes pediátricos con diagnóstico presuntivo de dengue que presenten fiebre ≥39 °C, mialgias, artralgias y dolor abdominal deben considerarse como potenciales casos de dengue grave.

Abstract: Background: Dengue continues to increase globally. Currently, the highest incidence of first infection occurs in paediatric population, where severe dengue fever is potentially lethal. This study characterizes the clinical profile of paediatric patients with dengue fever in the South of Mexico. Methods: We undertook a series case study of 133 paediatric inpatients who presented clinical diagnosis of non-severe dengue and severe dengue fever. We described univariate analysis as means or percentages, using 0.05 as significance level. We estimated the prediction of severe dengue considering clinical signs and symptoms only using GLMM (Generalised Linear Mixed Models). Results: 58% (77/133) patients had severe dengue. There were significant differences among the dengue groups, in the following signs and symptoms: Fever, abdominal pain, epistaxis and platelet count. Children older than four years old had a higher proportion of severe dengue (p<0.05). GLMM identified a group of four clinical signs and symptoms (fever ≥39 °C, myalgia, arthralgia and abdominal pain) as predictors of severe dengue. Conclusions: The results of this exploratory study suggest changes in the frequency of clinical signs and symptoms among paediatric inpatients. Paediatric patients with a presumptive diagnosis of dengue, showing fever of ≥39° C, myalgia, arthralgia and abdominal pain should be considered as potential cases of severe dengue.