Abstract INTRODUCTION The percentage of asymptomatic COVID-19 cases worldwide is estimated at 18–50%; 53% in Cuba specifically, and 58% in Havana, the Cuban capital and the 2020 epicenter of the country’s COVID-19 epidemic. These figures, however, do not represent the transmission capacity or behavior of asymptomatic cases. Understanding asymptomatic transmission’s contribution to SARS-CoV-2 spread is of great importance to disease control and prevention. OBJECTIVE Identify the epidemiological implications of asymptomatic SARS-CoV-2 infection in Havana, Cuba, during the first wave of the epidemic in 2020. METHODS We carried out a cross-sectional study of all confirmed COVID-19 cases diagnosed in Havana, Cuba, from March 16 through June 30, 2020. The information was obtained through review of the standardized form for investigation of suspected and confirmed cases. Examined variables included age, sex, occupation, case type and source of infection. Cases were divided into asymptomatic and symptomatic groups, and transmission was characterized through the creation of a contact matrix. Analysis was carried out in Epidat and R. RESULTS We studied 1287 confirmed cases, of which 57.7% (743) were asymptomatic, and 42.3% (544) were symptomatic. Symptomatic presentation was the most common for both imported and introduced cases, while asymptomatic presentation was more common in autochthonic cases and infections from an undetermined source. Asymptomatic infection was more common in groups aged <20 and 20–59 years, while symptomatic infection was more common in those aged >60 years. In the contact matrix, 34.6% of cases (445/1287) were not tied to other cases, and 65.4% (842/1287) were infectious–infected dyads, with symptomatic–symptomatic being the most common combination. The majority of primary cases (78.5%; 1002/1276) did not generate secondary cases, and 85.6% (658/743) of asymptomatic cases did not lead to other cases (although one asymptomatic superspreader led to 90 cases in a single event). However, 63.2% (344/544) of symptomatic primary cases generated secondary cases, and 11 symptomatic superspreaders spawned 100 secondary cases in different events. CONCLUSIONS Asymptomatic SARS-CoV-2 infection was the most common form of COVID-19 in Havana during the study period, but its capacity for contagion was lower than that of symptomatic individuals. Superspreader events under specific conditions played an important role in sustaining the epidemic.

ABSTRACT Introduction: The high transmission of COVID-19 has resulted in healthcare workers becoming infected while caring for patients and spreading the disease to other hospital patients or coworkers. Objective: To describe an in-hospital COVID-19 outbreak. Methods: A cross-sectional descriptive study conducted in March 2020 at the “General Calixto García Íñiguez” Clinical-Surgical University Hospital, Havana. The study included 545 individuals among patients and healthcare workers. The data was collected from the clinical-epidemiological profiles and the medical records. Each case was described using the following criteria: type of health worker, service provided, sex, signs, symptoms, and comorbidities. To determine the outbreak intensity, a contact matrix was created and the reproductive number and the dispersion value were calculated. Results: Of the 545 studied individuals, 30% were patients and 70% workers of seven services, 30 tested positive for SARS-CoV-2. Outbreak control actions were aimed at identifying, reporting and isolating sick individuals. The average age was 45 years. The clinical pictures was characterized by cough, dyspnea and asthenia. The most common comorbidities (60%) were hypertension, ischemic cardiopathology, and diabetes mellitus; 53.3% were asymptomatic and three people died. The attack rate was 5.5%. Conclusions: During the outbreak, medical doctors and nurses were the most affected. The timeliness of outbreak control actions and the quality of the epidemiological investigation are essential to ensure effective control.

RESUMEN Introducción: La alta transmisión de la COVID-19 propicia que el personal de salud contraiga la infección durante la atención a los pacientes con la probabilidad de propagarla a otros pacientes hospitalizados y compañeros de trabajo. Objetivo: Describir un brote intrahospitalario de COVID-19. Métodos: Estudio descriptivo, transversal realizado en el Hospital Universiario Clínico Quirúrgico “ General Calixto García” , La Habana en marzo de 2020. Se estudiaron 545 personas entre pacientes y trabajadores. Los datos se recolectaron mediante fichas clínico-epidemiológicas e historias clínicas. Los casos se describieron según: tipo de personal de salud, servicios que atienden, sexo, síntomas, signos y comorbilidades. Se realizó una matriz de contactos y para evaluar la intensidad del brote se calculó el número reproductivo y el valor de dispersion. Resultados: De los 545 estudiados, 30 % fueron pacientes y 70 % trabajadores de siete servicios, 30 tuvieron el diagnóstico confirmado de SARS-CoV-2. Las acciones de control de foco se dirigieron a la identificacion, notificacion y aislamiento de los enfermos. La edad promedio fue de 45 años, el cuadro clínico caracterizado por tos, disnea y astenia. Las comorbilidades más frecuentes (60 %) fueron hipertensión arterial, cardiopatia isquémica y diabetes mellitus, asintomaticos 53,3 % y tres fallecidos. La tasa de ataque fue de 5,5 %. Conclusiones: Los trabajadores más afectados son los médicos y las enfermeras. La oportunidad en las acciones del control de foco y la calidad en la investigacion epidemiológica son esenciales para lograr un control efectivo.

ABSTRACT Vaccination is one of the most cost-effective interventions for control of communicable diseases. This health achievement could founder if measures are not taken by health systems to prioritize immunization, increase vaccination rates and educate health professionals to address public concerns about vaccine safety and efficacy. Parents’ refusal to vaccinate their children directly affects public health, because it puts both individual and group immunity in danger; immunization coverage is effective only when high population coverage is attained. The growing number of antivaccination (antivaxxer) groups around the world is alarming, contributing to falling vaccination rates. Troubling consequences include disease outbreaks in several countries globally and in our hemisphere. This article looks at the history and features of antivaxxer movements around the world and proposes ways the Cuban health system, through its National Immunization Program, can address dangers for the population associated with potentially negative influences of social-network antivaxxer campaigns. The paper underscores the role of mass and social media, health professional training and sustained competence, and the importance of a vaccine-related adverse events surveillance system.

Introduction: the evaluation is conceived as the activity permitting to deliver judgments of value, to identify the gaps existing between the achievement of the goals and its behavior in a certain time, and the further proposal of measures for correction. Objective: to evaluate its components structure, process, and results. Material and methods: an evaluative revision of the rabies program was made in Pinar del Río Province in 2010. The information was collected by papers research, observation of processes, interviews with the human resources involved in the program; as synthetic means we used absolute frequencies, rates, and percentages. The criteria, indicators and standards were defined under normative and expert criteria. Results: the dimension structure was evaluated as inadequate, as it does not comply by the proposed standards. In the dimension process, the 66.6% of the examined indicators were evaluated as wrong or fair. The 66.6% of the indicators of the dimension results of the program were evaluated as wrong. Conclusions: the Rabies Program was evaluated as wrong.

Introducción: la evaluación está concebida como la actividad que permite emitir un juicio de valor, identificar las brechas existentes entre el cumplimiento de los objetivos y su comportamiento en un momento determinado, proponiendo posteriormente las medidas para su corrección. Objetivo: evaluar los componentes estructura, proceso y resultados del mismo. Material y métodos: se realizó una investigación evaluativa del programa de rabia en la provincia Pinar del Río en el 2010 La información se obtuvo mediante la revisión de documentos, observaciones de proceso, entrevistas a los recursos humanos implicados en el programa; se utilizaron como medidas de resumen frecuencias absolutas, razones, proporciones o porcentajes, y tasas; se definieron los criterios, indicadores y estándares sobre la base de criterios normativos y de expertos. Resultados: la dimensión estructura fue evaluada de inadecuada, no cumpliendo con el estándar propuesto. En la dimensión proceso, el 66,6% de los indicadores examinados resultaron regular o mal. El 66.6% de los indicadores en la dimensión resultado del programa se evaluaron de mal. Conclusiones: el programa de rabia fue evaluado de inadecuado.

An observational, analytical case-control study was carried out with the purpose of identifying the risk factors related to suicide attempt in adolescents in Pinar del Rio municipality from January to June 2009. The target group was comprised of the total population from 10 to 19 years old with suicide attempts; the sample consisted of 36 cases vs. 72 controls, chosen by a matching of 1:2, individual and familial risks factors associated with suicide attempt were analyzed as well. Data were obtained by means of the application of a questionnaire designed by the author of the study, the association between the risk factors and suicide attempt was determined using chi square test and the reason of crossed products ratio by punctual estimation and by confidence intervals; among the main results a significant statistical association to suicide attempt was found and the following risk factors: presence of mental disorders in adolescents (depression), mental retardation, schooling difficulties, involuntary boarding school and history of suicide attempt in other family members.

Se realizó un estudio observacional analítico de caso y control, con el objetivo de identificar los factores de riesgo relacionados con el intento suicida en los adolescentes del municipio Pinar del Río, en el período comprendido de enero a junio del 2009. El universo del estudio estuvo constituido por la población de 10 a 19 años con intento suicida, quedando conformada la muestra por 36 casos contra 72 controles, seleccionados por un pareo de 1:2, se analizaron los factores de riesgo individuales y familiares asociados al intento suicida. Los datos se obtuvieron mediante la aplicación de un cuestionario diseñado por la autora de la investigación, se determinó la asociación entre los factores de riesgo y el intento suicida, a través de la prueba de Chi cuadrado y la razón de productos cruzados (OR) con estimación puntual y por intervalos de confianza; entre los principales resultados se encontró asociación estadística significativa al intento suicida, de los siguientes factores de riesgo: la presencia de adolescentes con desordenes mentales como depresión y retraso mental, dificultades escolares e internamiento invo luntario y el antecedente de suicidio por otro miembro del hogar.