COVID-19 testing can identify the SARS-CoV-2 virus and includes methods that detect the presence of virus itself (RT-PCR and isothermal nucleic acid amplification) and those that detect antibodies produced in response to infection. Detection of antibodies (serology) can be used both for diagnosis and population surveillance. Antibody tests show how many people have had the disease, including those whose symptoms were minor or who were asymptomatic. An accurate mortality rate of the disease and the level of herd immunity in the population can be determined from the results of this test.
Due to limited testing, as of March 2020 no countries had reliable data on the prevalence of the virus in their population.[1] By 11 April, no country had tested more than 10% of its population, and there are variations in how much testing has been done across countries.[2] This variability is also likely to be affecting reported case fatality rates, which have probably been overestimated in many countries, due to sampling bias.
Utilizando la reacción en cadena de la polimerasa de transcripción inversa (rRT-PCR) en tiempo real, la prueba puede ser hecha en muestras respiratorias obtenidas por varios métodos, incluyendo la escobilla de algodón nasofaríngea o la muestra de esputo.23 Los resultados están generalmente disponibles entre unas cuantas horas y 2 días.4Los métodos moleculares apalancan la reacción molecular en cadena (PCR) junto con pruebas de ácido nucleico, y otras técnicas analíticas avanzadas, para detectar el material genético del virus, usando la reacción en cadena de la polimerasa de transcripción inversa en tiempo real, para propósitos de diagnóstico.
Una de las primeras pruebas PCR fue desarrollada en Charité en Berlín en enero de 2020 utilizando la reacción en cadena de la polimerasa de transcripción inversa (rRT-PCR) en tiempo real, y formó la base de 250,000 paquetes para su distribución por la Organización Mundial de la Salud (OMS).
