COVID-19 is not Just Another Flu

The above points make a strong argument that the diseases are pretty identical but the differences outnumber the few similarities. To begin with, there is a difference in the incubation period(time from infection to appearance of symptoms) and the period of contagiousness. The mean incubation period is 2 days for Influenza while that for COVID-19 is around 5 to 6 days. Somebody suffering from the flu can be infectious starting a day before they become sick to a maximum of 7 days after the onset of symptoms but this period is almost double for COVID-19. A person testing positive for SARS-CoV-2 can spread it to other people around 2 days before the onset of symptoms to around 10 days after they become sick. Thus, Influenza may spread faster but a COVID positive person can spread the disease for a longer time. Due to several asymptomatic COVID cases, transmission may occur without the person realising it. The secondary infections due to COVID are twice that of flu which ultimately leads to more cases and propagation of the disease at a faster rate.

Most people around the world are aware about the seasonal flu and how to deal with it. Since the human population is affected by it year after year, herd immunity has already developed. Even the healthcare workers know a great detail- the seasonal increase in flu cases every winter, complications arising out of this illness and the treatment to be given. Moreover, we have medicines that work against the Influenza virus and a vaccine that most people get annually. In short, we know a lot about the flu and how it works. This is not the case with COVID-19. Everyday, we learn more about it- new kinds of complications happening, different medicines and vaccines undergoing clinical trials at the fastest pace possible and herd immunity being nowhere in sight. Initially, there were theories of warm weather leading to a decrease in the spread of SARS-CoV-2 like we see with Influenza but that is not the situation right now as we see tropical countries with warm weather like Brazil, India fighting an equally hard battle. 

Another reason that makes the situation more grim is death. Presently, the mortality rate due to COVID-19 is around 3% which is high if we look at Influenza which stands at less than 1%. Fatalities occur more often in people with co-morbidities like cardiovascular diseases, hypertension, respiratory diseases like asthma or chronic obstructive pulmonary disease(COPD) and immunocompromised people like those battling cancer.

Another interesting but terrible feature of COVID-19 is “silent hypoxia” or as some others have dubbed it- “happy hypoxics”. It happens when people are unaware about their low body oxygen levels and function normally because their body compensates. As a result, they don’t feel sick and by the time they realise they are short of breath, the oxygen levels have plummeted further and their condition is critical which might even require a ventilator.

There are several other peculiar features surrounding this disease. SARS-CoV-2 is causing formation of clots in blood vessels leading to conditions like stroke, pulmonary embolism to name a few. “COVID toes” are blue, purple, pink or red lesions on toes that resemble chilblains seen in children and young adults. In children, COVID-19 may cause an inflammatory syndrome that resembles Kawasaki disease. Cytokine storm leading to acute respiratory distress syndrome(ARDS) and multi organ failure can be fatal because the body’s dysregulated immune response causes more damage to the body than the virus. These gamut of complications are unique to COVID-19 and we don’t see them in Influenza which reiterates how SARS-CoV-2 has a widespread effect on different systems of the human body.

As the world fights the pandemic, it has one less thing to worry about- Influenza. Lockdowns, masks, social distancing and hand hygiene measures have slowed the transmission of the seasonal flu ending the flu season earlier this year which usually continues till mid May.

COVID-19 and Influenza are two distinct diseases and treating them as similar, is only going to downplay the threat this new disease poses. As we wait for a vaccine or an effective drug, masks and social distancing become our armour in an attempt to mitigate the threat posed by COVID-19.