Predicción del fin del confinamiento después del máximo de casos en la primera ola de la pandemia COVID-19 en Chile / Prediction of end of lockdown post-peak of cases in first wave of the COVID-19 pandemic in Chile

Introducción Los resultados del confinamiento obligatorio han sido perjudiciales en varios aspectos. No obstante, han surtido efecto en lograr el descenso de casos activos de COVID-19. Chile ha comenzado la desescalada y precisa conocer el mejor momento para poner fin a las restricciones. Objetivos Discutir las mejores condiciones y garantías para el fin del confinamiento obligatorio sobre la base de los casos nuevos, casos activos y positividad de exámenes de reacción en cadena de la polimerasa. Métodos Estudio basado en un modelo de tendencia con estimación de predicciones. Los datos de las variables de interés fueron sometidas a estudios de regresión lineal, con el objeto de determinar la curva que mejor explicaba los datos. Se estimó el coeficiente de determinación, la desviación estándar de y en x y el intervalo de confianza de la curva observada. Posteriormente, fue escogida la curva de tendencia en concordancia con las estimaciones de regresión. Resultados Se encontró que todas las variables dependientes tendían a disminuir con el tiempo de forma cuadrática, con excepción de la variable casos nuevos. En general, las estimaciones de coeficiente de determinación (R2) y error porcentual absoluto medio son satisfactorias, con excepción de la variable: número de exámenes de reacción en cadena de la polimerasa por día. Conclusiones Se deben tomar medidas graduales y cautelosas antes de poner fin al confinamiento obligatorio. En la actual desescalada, se deben aumentar los exámenes de reacción en cadena de la polimerasa diarios y mantener vigilancia en los indicadores de incidencia, prevalencia y positividad de dichos exámenes. La evidencia sugiere con cierto grado de confiabilidad que el confinamiento obligatorio podría levantarse de forma segura a contar del día 30 de agosto de 2020. Se deben hacer preparativos a largo plazo en contención de las futuras olas, es decir, una nueva alza de casos nuevos y activos luego del descenso.

Introduction The results of mandatory confinement have been detrimental in several respects. Nonetheless, they have resulted in reducing the number of active cases of COVID-19. Chile has begun the de-escalation and needs to know the best time to end the restrictions. Objective We discuss the best conditions and guarantees for the end of compulsory confinement. Methods This study is based on a trend model with prediction estimation. The data of the variables of interest were subjected to linear regression studies to determine the curve that best explained the data. The coefficient of determination, the standard deviation of y in x, and the confidence interval of the observed curve were estimated. The trend curve was chosen in accordance with the regression estimates. Outcomes It was found that all dependent variables tended to decrease over time in a quadratic fashion, except for the new cases variable. In general, the R2 and MAPE estimates are satisfactory, except for the variable number of PCR tests per day. Conclusions Gradual and cautious steps should be taken before ending mandatory confinement. In the current de-escalator, daily PCR tests should be increased, maintaining vigilance on indicators of incidence, prevalence, and positivity of PCR tests. Evidence suggests with some degree of confidence that mandatory confinement could be safely lifted as of August 30, 2020. Long-term preparations must be made to contain future waves of new cases.

Utilization of the respiratory virus multiplex reverse transcription-polymerase chain reaction test for adult patients at a Korean tertiary care center

BACKGROUND/AIMS: Respiratory viruses (RVs) are considered to be important respiratory pathogens in adult patients, and the multiplex reverse transcription-polymerase chain reaction (RT-PCR) test is used frequently in adult patients with respiratory infections. However, clinical data regarding utilization of the multiplex RT-PCR test for RVs are lacking. METHODS: We investigated the utilization of the multiplex RT-PCR test for RVs at Chung-Ang University Hospital in Seoul, Korea, between January 2012 and April 2013. RESULTS: During the study period, the multiplex RT-PCR test was performed for 291 adult patients. The test frequency was 4.9% of rapid influenza antigen detection tests and 0.8% of respiratory bacterial culture studies. A turnaround time of < 48 hours was observed in 25.9% of positive tests. Most of the tests were performed for admitted patients (97.9%) with a community-acquired infection (84.2%) during the flu season (82.5%). RVs were detected in 81 of 291 cases (27.8%). The RV positivity rates for community- and hospital-acquired infections did not differ (28.6% vs. 23.9%, p = 0.52). Of 166 patients with pneumonia, 44 (26.5%) had a viral infection. Among the patients with RV-associated pneumonia, an RV other than influenza was detected in 20 patients (45.4%). CONCLUSIONS: The multiplex RT-PCR test for RVs was infrequently performed at a tertiary care center, and the test results were often reported late. The test was most often performed for admitted adult patients with community-acquired infections during the flu season. The utilization of multiplex RT-PCR testing for RVs in current clinical practice should be improved.