It all appears so normal until it is affirmed positive after a simple test – meet the silent and invisible asymptomatic Covid-19 infections.
Individuals contracted the SARS-CoV-2 virus don’t develop fever, cough and shortness of breath. It seems the typical alarm bell which we are educated about of Covid-19 infections no longer rings true – and the threat to containing the spread lies with us who have been unknowingly infected and thus carrying and propagating the virus.
Asymptomatic Covid-19 infections which affected only a segment of society during the onset of the pandemic now make up the majority of new cases. In fact, in Malaysia, 96.8% of 15,902 new patients reported on July 24, 2021 belonged to categories 1 and 2, which are either asymptomatic and exhibiting mild symptoms. This just shows there is so much yet to be learned about the virus, not to mention the constant mutations which will undoubtedly generate more swells.
While on the surface, having little to no symptoms may seem better off than having to be hospitalised, the situation remains fluid. During the period of self-isolation, symptoms may manifest. Health may regress quickly rendering patients who are in the less severe category be escalated for enhanced treatment in the hospital. It also doesn’t necessarily mean that those who aren’t as severely affected by the virus are exempted from the same sort of damage the virus is known to cause to our bodies.
Here we dissect what asymptomatic Covid-19 infections actually mean to lay people like you and me.
The US National Institutes of Health states:
Asymptomatic or pre-symptomatic infection: Individuals who test positive for SARS-CoV-2 using a virologic test without symptoms consistent with Covid-19.
Mild illness: Individuals who have any of the symptoms such as fever, cough, sore throat, malaise, headache, muscle pain, nausea, vomiting, diarrhoea, and loss of taste and smell, but don’t exhibit shortness of breath or abnormal chest imaging.
Moderate illness: Individuals who exhibit lower respiratory disease during clinical assessment or imaging and who have blood oxygen levels of at least 94% and above.
Severe illness: Individuals who have blood oxygen levels lower than 94%, high breathing rates and signs of severe lung disease.
Critical illness: Individuals who have respiratory failure, septic shock, and/or multiple organ dysfunction.
Over in Malaysia, the 5 categories can be broadly defined as such: 1 – asymptomatic; 2 – symptomatic, no pneumonia; 3 – symptomatic, pneumonia; 4 – symptomatic, pneumonia, requiring supplemental oxygen; and 5 – critically ill with multi-organ involvement.
In category 1 only the RT-PCR test is proven positive, while category 2 shows upper respiratory tract symptoms such as pharyngeal congestion, sore throat, cough or fever for a period less than 7 days.
According to the same guideline above published by the Malaysia Ministry of Health, categories 1 and 2 patients require no treatment, however, close observation of vital signs and oxygen saturation is advised for the latter.
A study conducted in South Korea in 2020 finds people who are asymptomatic carry just as high a viral load as those who exhibit the usual signs of an infection. Although the objective of this study isn’t about determining whether asymptomatic people can spread the virus as easily as their symptomatic counterparts, another study published this year, completed at the time the Delta variant was yet to be identified, concludes that asymptomatic individuals can infect nearly as efficiently as symptomatic individuals.
Individuals in younger age groups tend to show no to little symptoms. There is evidence, however, those recovered from a mild malady may suffer from a long Covid.
According to the United State Center of Disease Control, even though children are less affected by the virus, they can still readily transmit the virus just like adults with Covid-19 and are asymptomatic.
The UK National Health Service lists fatigue, shortness of breath, chest pain or tightness, brain fog, insomnia, heart palpitations, dizziness, pins and needles, joint pain, depression and anxiety, tinnitus, earaches, feeling sick, diarrhoea, stomach aches, loss of appetite, a high temperature, cough, headaches, sore throat, and changes to sense of smell or taste rashes.
According to John Swartzberg, professor emeritus of UC Berkeley’s School of Public Health, computerised tomography scans of asymptomatic patients found that they had some scar tissue. He explains that if lung tissue is replaced by scar tissue, it no longer functions as regular pulmonary tissue, thus resulting in poor gas exchange.
Separately in a CBS report, trauma surgeon Dr Brittany Bankhead-Kendall discovers that every symptomatic patient she treated exhibited abnormal chest X-ray. Of four asymptomatic patients, three had a bad chest x-ray.
Meanwhile, another report indicates 54% of asymptomatic individuals boarded the Diamond Princess cruise ship showed lung opacities, reflecting the filling of the air spaces in the lungs with fluid relating to edema (swelling), fibrosis (scarring) and inflammation.