You have been hearing a lot about Coronavirus – COVID-19, precautions to take, PCR and Rapid Test or RDT, quarantine/confinement and lots of other matters due to the current pandemic. But do you really know what all these terminologies mean?
Our Infectious Diseases and Virology specialist Dr. Zuhayr Tabbarah, Internal Medicine & Infectious Diseases, answers these questions and all you need to know about the virus, pandemic, and its measures.
SARS-CoV-2 or Severe Acute Respiratory Syndrome-Coronavirus 2 is the virus strain causing the current pandemic. COVID-19 is the disease caused by the infection with SARS-CoV-2. SARS-CoV-2 can be detected in people who are Asymptomatic, Pre-Symptomatic (1-3 days before symptoms), Symptomatic and Post-Symptomatic. Persons in the Pre-symptomatic and Symptomatic period can transmit the virus effectively to others. COVID-19 symptoms vary in severity:
• Mild: no need for in-patient care (Majority of cases)
• Moderate: requires hospitalization typically due to pneumonia
• Severe: requires intensive care and can cause respiratory failure.
SARS-CoV-2 incubation period is 2-14 days (time for symptoms to appear). Most infected persons show symptoms by 11 days of infection. COVID-19 symptoms include: cough, sore throat, congestion or runny nose, new loss of smell or taste, shortness of breath or difficulty breathing, fever, chills, fatigue, muscle aches, nausea, vomiting and diarrhea.
Now that you know more about the virus and its disease, what are the PCR and Rapid tests that everyone is talking about? Two types of tests are available to diagnose COVID-19 and detect current and past infection.
• Molecular Tests, better known as PCR (Polymerase Chain Reaction) / NAAT (Nucleic Acid Amplification Tests) detect the genetic material of the virus. This requires sophisticated equipment, special training, complicated procedures and use of dedicated reagents with turnabout time (TAT) of several hours.
SARS-CoV-2 viral genetic material can be detected 1-3 days prior to symptoms and remains detectable at high levels for about 6-7 days. Then it substantially decreases to negligible levels after 10 days after onset of symptoms.
• Antigen Detection tests or RDT (Rapid Diagnostic Test) detects viral antigenic proteins or antibody production due to infection and does not need expensive machines, is a faster (provide yes-or-no-results on the spot), cheaper and easier test to perform, but its sensitivity and specificity is lower than the PCR, with turnabout time (TAT) of 10 mins to 5 hours. The antigen tests are used to diagnose present infection. Whereas the antibody tests are used to detect past infections and are helpful to determine the extent of spread of the virus in the community.
COVID-19 is a serious disease and a killer disease and should be handled accordingly. Think about yourself and the people in your life and act responsibly. There has been some ambiguity early in the pandemic about the virus being transmitted by droplets or airborne, but today the possibility of SARS-CoV-2 airborne transmission is accepted. However, the predominant mode of transmission is likely via respiratory droplets from coughing, sneezing or talking. You all heard the recommendations for prevention and we cannot stress more on them:
• Maintain Social Distancing – 2 meters
• Wash Hands often with Soap and Water
• Disinfect frequently touched surfaces regularly
• Inactivate SARS-CoV-2 with ethanol-based solution 62-71% in 1 min
• Wear Face Masks – surgical masks have proven effective to prevent human transmission from symptomatic carriers
A recurrent outbreak is most likely to happen after initial pandemic outbreak, yet the interval and height of coming wave depends on multiple factors including control measures. Stay vigilant and get prepared for around 12 to 24 months of significant COVID-19 activity with periodic hot spots in different regions in Lebanon and elsewhere.
Is there still need for Quarantine now that the lockdown is removed? Well, there is no logical ground to treat returning travelers differently except doing the PCR test. Based on the incubation period of SARS-CoV-2, two negative PCR within 48-72 hours in an asymptomatic person make the possibility of infection unlikely but not nil. Increasing the interval between the two tests to 6-7 days may obviate the need for quarantine.
And finally, Dr. Tabbarah advises: “My Take Home Message to you is: COVID-19 apparently is going to stay with us for a long time with recurrent waves. Wear face masks, abide with social distancing rules and maintain hands hygiene. These are the only available tools currently for prevention.”
CALL 1291 for any further information or should you need to consult with our specialist.