Even as the COVID-19 pandemic appears to be on its last legs, few cases of infection continue to be reported in many parts of India as well as across the world, along with the looming threat of a third wave owing to the rise of new COVID-19 variants. And although the COVID-19 vaccination drive is progressing at a rapid pace in many nations, healthcare experts and doctors still caution people to continue to wear masks and maintain social distancing wherever possible in public venues.
This is because, besides the spread of coronavirus infection from sick to healthy individuals by direct contact or touching contaminated objects/surfaces, COVID-19 can also be airborne in confined air-conditioned spaces without sufficient ventilation. Additionally, scientists have established through numerous research studies, that even asymptomatic persons and those who have recently recovered from the disease are capable of transmitting the pathogenic particles through viral shedding.
What Is Viral Shedding?
Viral shedding is a phenomenon wherein the pathogenic vector – SARS-CoV-2 viral particles, upon attaching themselves to the cells in the host – the human body, continue to be released into the outside environment as infectious agents, while coughing, sneezing, talking and even merely exhaling. Viral residues are eliminated even in the stool of the affected person, which can also spread germs and disease if not disposed of properly and promptly.
Mechanism Of Viral Shedding:
A virus is basically a microorganism with RNA as the core genetic material, that requires a host for its survival and proliferation. With many viral strains of the coronavirus family, like in Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS) as well as in the case of COVID-19, the human body that it invades via the nasal and oral pathways is the host. These strains of coronavirus are enveloped viruses, which means that they need to obtain a prominent membrane from the host system with ample viral proteins to form a stable outer structure.
When SARS-CoV-2 vectors get attached to the cells in the human body via their spike proteins, the capsid – which is the protein-rich outer shell of the virus, forms a close association with the cell membrane of the host and multiplies. They then extend this connection to the tail of the virus that helps to shape a rigid outer structure for the viral particles to “shed” or exit the host cell and travel to other cells within the same host, or move on to different hosts. This mechanism of viral shedding in enveloped viruses such as SARS-CoV-2 and HIV is known as budding.
How Long Does Viral Shedding Continue Post Recovery?
Viral shedding is not only an occurrence in moderate to severe cases of corona positive patients who undergo intense treatment or even hospitalization due to critical symptoms but also takes place in asymptomatic and mild infection. However, the nature of viral shedding differs depending upon at which stage of infection it happens, making it either infectious or weakened and thus not triggering any illness.
In-depth research into the progression of COVID-19 in several patients by doctors and medical researchers has determined that viral shedding that occurs during the start of illness prior to any noticeable signs and up to 14 days post the onset of symptoms (which is usually about 5 – 7 days after infection) invariably comprises infectious particles of SARS-CoV-2. Hence for the majority of COVID-19 patients, active viral load and infection declines after 21 days and so does their potential to transmit disease via direct contact or viral shedding. Shedding of RNA viral remnants after treatment and recovery of COVID-19 is mostly not infectious, comprising only weakened virus particles. However, some instances of viral shedding and subsequent spread of COVID-19 infection have been observed in children, elderly and immunocompromised individuals who have tested positive for coronavirus even after their complete recovery.
Viral shedding is an inevitable phenomenon accompanying the onset of COVID-19 in people of all age groups. However, there is no need for healthy individuals or the general public to panic, fear or worry that even patients who have fully recovered from infection might still be capable of spreading COVID-19. Following the basic requisite safety precautions of wearing face masks when interacting with anyone in public places and sanitizing hands frequently helps to curb the widespread transmission of coronavirus infection, so as to stay healthy and disease-free.