Leptospirosis as a cause of infertility in Uruguayan beef cattle.

Leptospirosis, caused by pathogenic spirochetes of the genus Leptospira spp., is a globally significant zoonotic disease that affects humans and animals. In cattle, leptospirosis is associated not only with overt clinical manifestations but also with reproductive diseases, including infertility. This study assesses the potential correlation between leptospirosis and infertility in Uruguayan beef cattle. A case-control study involved 31 beef herds with no prior history of Leptospira vaccination. In each herd, veterinarians identified 10 non-pregnant (cases) and 25 pregnant cows (controls) using ultrasound, and blood and urine samples were collected from each cow. Serological diagnosis was performed using the Microscopic Agglutination Test (MAT), and quantitative PCR (qPCR) was used to assess Leptospira excretion. Additionally, antibodies against bovine viral diarrhea virus (BVDV) and infectious bovine rhinotracheitis (IBR) were tested. The results demonstrated an association between seropositivity to the Sejroe serogroup (cut-off 1:200) and infertility in cattle (OR=1.31; p-value=0.06). Furthermore, the level of Leptospira excretion (qPCR) in urine was associated with increased infertility risk, with cows excreting over 100 copies per mL of urine having the highest odds of infertility (OR=2.34; p-value<0.01). This study suggests a potential association between leptospirosis and infertility in Uruguayan beef cattle, emphasizing the importance of both serological and molecular diagnostics for assessing reproductive health in cattle herds. Future research should explore the impact of Leptospira serogroups on other reproductive disorders in cattle.

Epidemiology of dog bites to people in Uruguay (2010-2020).

BACKGROUND: Dog bites to people are a serious public health problem. Limited information exists at the country level in Latin America. The COVID-19 pandemic changed people's lifestyles and their relationship with pets, and this could potentially affect the incidence of dog bites injuries. OBJECTIVE: The main objectives of our study were to determine the prevalence of dog-bite injuries in Uruguay from 2010 to 2020 and to compare the prevalence in 2020 to that of pre-pandemic years. METHODS: Cross-sectional study. Dog-bite notifications for the 2010 and 2020 period were analysed using data from the Uruguayan Ministry of Public Health. RESULTS: The annual dog-bite injury rate for the 2010-2020 period was 87.51 per 100,000 people. The frequency of bites varied with the victims' sex, with males accounting for 51.8% of the bites (p < 0.0001), and with age, with a higher frequency of bites in the ≤14 years old age group (p < 0.01). The frequency of dog bites was also higher in spring and summer than in autumn (p < 0.0001). There was no statistical difference in the frequency of dog-bite injuries when comparing 2020 with the pre-COVID-19 pandemic years. CONCLUSIONS: In Uruguay, the frequency of dog-bite injuries varied with season and with the age and sex of the victim. In the first year of the COVID-19 pandemic, the number of people bitten by dogs was no different than that of previous years. This is the first study in Latin America to report national rather than regional data and to include all age groups.

Analytic Sensitivity of an ELISA Test on Pooled Sera Samples for Detection of Bovine Brucellosis in Eradication Stages in Uruguay.

Bovine brucellosis has been under eradication in Uruguay since 1998. The eradication program includes, among other interventions, individual sera sampling of beef animals at slaughter, and annual serum testing of all dairy cows-accounting for two million samples annually. At a herd prevalence of 0.8%, a pooled-sera sample approach could reduce the economic burden of the surveillance system by reducing the testing and operational costs. Our objective was to evaluate the analytic sensitivity of an indirect ELISA test for Brucella abortus in serum pools. Sixty-two Brucella abortus-positive bovine sera samples (based upon rose bengal and fluorescent polarization assay) were used as the positive control samples. Rose bengal-negative sera from negative farms were used to dilute the positive samples to the desired concentrations. Positive samples were diluted by using 1 ml of positive sera and 1 ml of negative sera (1/2 dilution) up to 1/1,024. Data were analyzed using generalized linear mixed models with a binary outcome (positive or negative), dilution number as a fixed effect, and a random effect for sample ID. Analytic sensitivity was 99.0% [95% confidence interval (CI): 96.3-99.7], 98.3% (95% CI: 93.1-99.6), 97.3% (95% CI: 87.4-99.4) for dilutions 1/2, 1/4, and 1/8, respectively. The analytical sensitivity, however, decreased when diluted to greater proportions. Given the current herd prevalence in Uruguay, it seems plausible that the use of a pooled sample approach could be adopted by policymakers to reduce the cost of the surveillance program and increase the number of samples being tested.

Epidemiological study of neosporosis in Uruguayan dairy herds.

Neosporosis is one of the leading causes of abortion in cattle worldwide, posing a great economic burden on cattle producers. The aim of this study was to determine the national seroprevalence and putative risk factors of Neospora caninum (N. caninum) in dairy cattle in Uruguay. A cross-sectional study was carried out. Herds were stratified by size (1-50, 51-250, and >250 cattle) and up to 60 dairy cows per herd were randomly selected. Four thousand two hundred twenty-three serum samples from 102 dairy herds were analyzed by indirect ELISA test, under the manufacturer's recommendations. In addition, the herdsman was surveyed and a population study was carried out. The in degree data, geographical coordinates, and seroprevalence of bovine viral diarrhea, enzootic bovine leukemia and infectious bovine rhinotracheitis were available for each herd. A sampling design was used to estimate population seroprevalence of N. caninum. In order to determine the factors associated with the disease, herds with an intra-herd seroprevalence over 20% were considered as case herds. Seroprevalence of N. caninum was 22.3% (95% CI: 18.7-25.9 %) and 96.0% (95% CI: 92.1-99.8%) at the animal and herd level, respectively. The number of dogs on the dairy farms were associated with infection levels (OR: 1.43, 95% CI: 1.02 to 2.03). It was concluded that N. caninum is endemic in the country, and is spreading over dairy herds. Although this study showed evidence that the number of dogs were associated with high levels of infection, more studies should be conducted, to better understand the epidemiology of the disease and thus develop efficient control measures.

Introduction of the Japanese encephalitis virus (JEV) in the United States - A qualitative risk assessment.

The purpose of this risk assessment (RA) was to qualitatively estimate the risk of emergence of the Japanese encephalitis virus (JEV) in the United States (US). We followed the framework for RA of emerging vector-borne livestock diseases (de Vos et al. 2011), which consists of a structured questionnaire, whose answers to questions can be delivered in risk categories, descriptive statements, or yes or no type of answers, being supported by the literature. The most likely pathways of introduction of JEV identified were: (a) entry through infected vectors (by aircraft, cargo ships, tires, or wind); (b) import of infected viremic animals; (c) entry of viremic migratory birds; (d) import of infected biological materials; (e) import of infected animal products; (f) entry of infected humans; and (g) import/production of contaminated biological material (e.g., vaccines). From these pathways, the probability of introduction of JEV through infected adult mosquitoes via aircraft was considered very high and via ships/containers was deemed low to moderate. The probability of introduction via other pathways or modes of entry (vector eggs or larvae, hosts, and vaccines) was considered negligible. The probability of transmission of JEV was variable, ranging from low to high (in the presence of both competent vectors and hosts), depending on the area of introduction within the US. Lastly, the probability of establishment of JEV in the continental US was considered negligible. For that reason, we stopped the risk assessment at this point of the framework. This RA provides important information regarding the elements that contribute to the risk associated with the introduction of JEV in the US. This RA also indicates that infected mosquitoes transported in aircraft (and cargo ships) are the most likely pathway of JEV entry and therefore, mitigation strategies should be directed towards this pathway.

A quantitative risk assessment (QRA) of the risk of introduction of the Japanese encephalitis virus (JEV) in the United States via infected mosquitoes transported in aircraft and cargo ships.

Following a qualitative risk assessment, in which we identified and assessed all viable pathways for the introduction of the Japanese encephalitis virus (JEV) into the United States (US), we identified entry through infected vectors via aircraft and cargo ships as the most likely pathway, and thus considered it further in a quantitative risk assessment (QRA) model. The objective of this study was to evaluate the risk of introduction of JEV in the US via infected mosquitoes transported in aircraft and cargo ships arriving from Asia, using a QRA model. We created a stochastic model to quantify the probability of introduction of at least one infected mosquito in the continental US via aircraft and cargo ships, per at-risk period (March to October) or year, respectively. We modeled the following parameters: number of flights (per at-risk period, i.e., March to October) and cargo ships (per year) and per region, number of mosquitoes per flight and ship, number of mosquitoes that were not found and sensitivity of the mosquito collection method in aircraft, mosquito infection rates, and number of mosquitoes coming in aircraft per at-risk period (March to October) and cargo ships per year. Flight and cargo ship data pertained to years 2010-2016. For model building purposes, we only considered port-to-port vessels arriving from Asia to the US, we assumed that mosquitoes survive the trans-Pacific Ocean ship crossing and that the number of mosquitoes in cargo and passenger flights is similar. Our model predicted a very high risk (0.95 median probability; 95% CI = 0.80-0.99) of at least one infected mosquito being introduced in the US during the at-risk period, i.e., March to October, via aircraft transportation from JEV-affected countries in Asia. We also estimated that a median of three infected mosquitoes can enter the US during the at-risk period, i.e., March to October (95% CI = 1-7). The highest probability of introduction via aircraft was attributed to the Mediterranean California ecoregion (0.74; 95% CI = 0.50-0.90). We predicted, however, a negligible risk (0; 95% CI = 0.00-0.01) of at least one infected mosquito being introduced via cargo ships. Although the risk of introduction of JEV-infected mosquitoes by cargo ships was negligible, the risk via aircraft was estimated to be high. Our findings indicate the need to prioritize JEV prevention and control methods for aircraft-based pathways, such as aircraft disinfection. The quantitative estimates provided in this study are of interest to public health entities and other stakeholders, as they may support future interventions for preventing JEV introduction, as well as other vector-borne diseases, in the US and other countries.

Assessment of data on vector and host competence for Japanese encephalitis virus: A systematic review of the literature.

Japanese encephalitis virus (JEV) is a virus of the Flavivirus genus that may result in encephalitis in human hosts. This vector-borne zoonosis occurs in Eastern and Southeastern Asia and an intentional or inadvertent introduction into the United States (US) would have major public health and economic consequences. The objective of this study was to gather, appraise, and synthesize primary research literature to identify and quantify vector and host competence for JEV, using a systematic review (SR) of the literature. After defining the research question, we performed a search in selected electronic databases and journals. The title and abstract of the identified articles were screened for relevance using a set of exclusion and inclusion criteria, and relevant articles were subjected to a risk of bias assessment, followed by data extraction. Data were extracted from 171 peer-reviewed articles. Most studies were observational studies (59.1%) and reported vector competence (60.2%). The outcome measures reported pertained to transmission efficiency, host preference, and vector susceptibility to infection within vector competence; and susceptibility to infection within host competence. Regarding vector competence, the proportion of JEV infection reported across all 149 mosquito species in all observational studies ranged from 0 to 100%. In experimental studies, infection, dissemination, and transmission rates varied between 0 and 100%. Minimum infection rates (MIR) varied between 0 and 333.3 per 1000 mosquitoes. Maximum likelihood estimation (MLE) values ranged from 0 to 53.8 per 1000 mosquitoes. The host species in which mosquitoes mostly fed consisted of pigs and cattle (total of 84 blood meals taken by mosquitoes from each of these host species). As for host competence, the proportion of JEV infection varied between 0 (in rabbits, reptiles, and amphibians) and 88.9% (cattle). This SR presents comprehensive data on JEV vector and host competence, which can be used to quantify risks associated with the introduction of JEV into the US.

Meta-Analyses of Japanese Encephalitis Virus Infection, Dissemination, and Transmission Rates in Vectors.

The objective of this work was to summarize and quantify Japanese encephalitis virus (JEV) infection, dissemination, and transmission rates in mosquitoes, using a meta-analysis approach. Data were obtained from experimental studies, gathered by means of a systematic review of the literature. Random-effects subgroup meta-analysis models by mosquito species were fitted to estimate pooled estimates and to calculate the variance between studies for three outcomes of interest: JEV infection, dissemination, and transmission rates in mosquitoes. To identify sources of heterogeneity among studies and to assess the association between different predictors (mosquito species, virus administration route, incubation period, and diagnostic method) with the outcome JEV infection rate in vectors, we fitted univariable meta-regression models. Mosquito species and administration route represented the main sources of heterogeneity associated with JEV infection rate in vectors. This study provided summary effect size estimates to be used as reference for other investigators when assessing transmission efficiency of vectors and explored sources of variability for JEV infection rates in vectors. Because transmission efficiency, as part of vector competence assessment, is an important parameter when studying the relative contribution of vectors to JEV transmission, our findings contribute to further our knowledge, potentially moving us toward more informed and targeted actions to prevent and control JEV in both affected and susceptible regions worldwide.

Regulación voluntaria de la actividad contráctil del músculo masetero en individuos sanos y con trastornos temporomandibulares. Un potencial test diagnóstico / Voluntary regulation of the contractile activity of the masseter muscle in healthy individuals vs. patients with temporomandibular disorders: a potential diagnostic test

El presente trabajo buscó analizar aspectos electrofisiológicos del control voluntario de la actividad contráctil del músculo masetero estudiando una nueva variable, presentada previamente por nuestro grupo. Con este objetivo se realizó un estudio comparativo entre un grupo de voluntarios sanos y otro de pacientes con trastornos temporomandibulares. Se utilizó un sistema experimental que utilizó retroalimentación visual a tiempo real para controlar el esfuerzo contráctil del músculo masetero y se calculó para cada registro electromiográfico, el tiempo que cada individuo necesitó para controlar la trayectoria de la actividad motora. Los coeficientes de variación y los desvíos estándar fueron diferentes entre los grupos analizados (p< 0.01 y p=0.02 respectivamente). Un coeficiente de variación mayor a 0.936 fue encontrado, determinando de esta manera, una especificidad del 93.7%. Asimismo se verificó una sensibilidad del 60%. Esta nueva variable mostró un potencial diagnóstico prometedor, con alta especificidad. Es posible que la sensibilidad pueda aumentarse si se realizan más repeticiones para cada individuo, de modo de analizar mejor el impacto de la dispersión.

This study analyzed the electrophysiological aspects of the voluntary control of the contractile activity of the masseter muscle studying a new variable, previously presented by our group. We conducted a comparative study among healthy volunteers and patients with temporomandibular disorders. We used an experimental system that included real time visual feedback to control the contractile effort of the masseter muscle. The time that each individual needed to control the trajectory of the motor activity was calculated for each electromyographic record. Coefficients of variation and standard deviations were different in the groups analyzed (p<0.01 and p = 0.02 respectively). We found a coefficient of variation greater than 0.936, which determines a 93.7% specificity. Additionally, a 60% sensitivity was verified. This new variable showed promising diagnostic potential, with high specificity. Sensitivity can be increased if more repetitions are conducted for each individual, so as to better analyze the impact of dispersion.

Meta-analyses of the proportion of Japanese encephalitis virus infection in vectors and vertebrate hosts.

BACKGROUND: Japanese encephalitis (JE) is a zoonosis in Southeast Asia vectored by mosquitoes infected with the Japanese encephalitis virus (JEV). Japanese encephalitis is considered an emerging exotic infectious disease with potential for introduction in currently JEV-free countries. Pigs and ardeid birds are reservoir hosts and play a major role on the transmission dynamics of the disease. The objective of the study was to quantitatively summarize the proportion of JEV infection in vectors and vertebrate hosts from data pertaining to observational studies obtained in a systematic review of the literature on vector and host competence for JEV, using meta-analyses. METHODS: Data gathered in this study pertained to three outcomes: proportion of JEV infection in vectors, proportion of JEV infection in vertebrate hosts, and minimum infection rate (MIR) in vectors. Random-effects subgroup meta-analysis models were fitted by species (mosquito or vertebrate host species) to estimate pooled summary measures, as well as to compute the variance between studies. Meta-regression models were fitted to assess the association between different predictors and the outcomes of interest and to identify sources of heterogeneity among studies. Predictors included in all models were mosquito/vertebrate host species, diagnostic methods, mosquito capture methods, season, country/region, age category, and number of mosquitos per pool. RESULTS: Mosquito species, diagnostic method, country, and capture method represented important sources of heterogeneity associated with the proportion of JEV infection; host species and region were considered sources of heterogeneity associated with the proportion of JEV infection in hosts; and diagnostic and mosquito capture methods were deemed important contributors of heterogeneity for the MIR outcome. CONCLUSIONS: Our findings provide reference pooled summary estimates of vector competence for JEV for some mosquito species, as well as of sources of variability for these outcomes. Moreover, this work provides useful guidelines when interpreting vector and host infection proportions or prevalence from observational studies, and contributes to further our understanding of vector and vertebrate host competence for JEV, elucidating information on the relative importance of vectors and hosts on JEV introduction and transmission.

Prevalence of carcass bruises as an indicator of welfare in beef cattle and the relation to the economic impact.

The objective of this work was to characterize bruises in bovine carcasses in Uruguay and to evaluate the economic impact. Thirteen abattoirs were visited during 2 years and bruises were identified, classified, and quantified by zone and degree (depth and size). One hundred carcasses were separated and bruises were cut out and weighed separately. From a total of 15 157 carcasses observed, 60.0% had at least one bruise; 42.0% of these had bruises on both sides. The expensive butt zone was the most damaged, followed by rib, shoulder and loin, respectively. The mean weight and standard error of the condemned trimmed meat was 1602 ± 212 g. It suppose a loss of 899 g per animal slaugtered in Uruguay. In a country sending 2.5 million heads of cattle to be slaughter yearly, this indicates an important financial loss. Improving transport conditions and personnel skills will probably result in a better welfare for the animals as well as better financial profit.

Cirugía de los aneurismas de aorta abdominal: resultados de los últimos 10 años en el Hospital de Clínicas / Surgery of abdominal aortic aneurysms: results of the last 10 years at the Hospital de Clinicas

Con el objetivo de conocer la frecuencia y los resultados de la cirugía de los aneurismas de aorta abdominal (AAA) en el Hospital de Clínicas de Montevideo, se recabaron los datos de los pacientes intervenidos entre enero de 1988 y julio de 1998. Se operaron 63 enfermos, 35 de coordinacion y 28 de urgencia, entre estos últimos 21 aneurismas rotos. La mortalidad hospitalaria de la cirugía de coordinacion fue de 8,5 por ciento y la de los aneurismas con rotura de 81 por ciento. El 27 por ciento de los pacientes tuvieron complicaciones intraoperatorias y el 34 por ciento desarrollaron complicaciones postoperatorias graves. Se analizan la presentación clínica, estudios realizados y resultados del tratamiento quirúrgico. La morbimortalidad de esta cirugía fue mayor que la publicada recientemente por los centros de referencia en cirugía vascular; se discuten los factores que pueden haber influido en estos resultados.