Today, Hugo López-Gatell, a public officer from Health Secretary in Mexico, informed that there is a confirmed coronavirus case in the country.
The patient, already diagnosed with COVID-19 is a 35 years old resident of Mexico City who recently traveled to the north of Italy, actually he is isolated at National Institute of Respiratory Diseases (INER) and presents mild symptoms. Patient’s family is also isolated and at the moment they do not present any symptom.
Case was confirmed after two positive tests for the virus and processed at INER and also at the Institute of Diagnosis and Epidemiological Reference (InDre) for corroboration.
There is another suspicious case, a 41-year-old man at Sinaloa State, which already has one positive test in a local laboratory and is waiting for confirmation from InDre. This person is isolated at a hotel.
On recent days, Marc Lipsitch, a Harvard University epidemiologist, predicted that coronavirus can not be contained and that in approximately one year, around 40% to 70% of world’s population would be infected; however, he also pointed that people should not be alarmed, since most cases will be mild or even asymptomatic.
Laboratory tests to detect the SARS-CoV-2 virus, responsible for the disease, are known as Real-Time Reverse Transcriptase Diagnostic Panel (RT-PCR), which are able to detect specific components of the virus in samples obtained from upper or lower respiratory tract.
It is important to acknowledge that many institutions are working right now to develop different and more accurate laboratory tests, since RT-PCR sensitivity is relatively low, around 60% to 71%, which means that if a hundred infected patients are tested, 60 to 71 will be detected, but 40 to 29 patients could not be diagnosed, this is the reason that symptomatic patients which have negative results require subsequent testing.
Due to the facts previously commented, the Radiologic Society of North America, in a public statement published yesterday, pointed the relevance of the Computed Tomography for the COVID-19 diagnosis. In a paper recently published in their journal Radiology, CT scans had a 98% sensitivity, which means it can detect 98 of each hundred sick patients, a finding that supports its use for detection of the disease, especially in patients who are symptomatic and had negative results in laboratory tests.
In this scenario, teleradiology plays an important role, since it allows image distribution from hospitals which have CT scanners but do not have radiologists or where radiologists have little or no experience in chest imaging, to hospitals with experienced personnel to make the diagnosis.