Viruses are tiny microbes that survive by invading other living cells. Both covid-19 and seasonal flu are viral infections but covid-19 is due to the SARS-CoV-2 virus, and flu is from influenza A and B viruses. There are 4 types of seasonal influenza viruses, types A, B, C and D. Influenza A and B viruses circulate and cause seasonal epidemics of disease. Seasonal influenza spreads easily and can sweep through schools, nursing homes, businesses or towns. When an infected person coughs, infected droplets get into the air and another person can breathe them in and be exposed.
Covid-19 and influenza viruses have a similar disease presentation. That is, they both cause respiratory disease, which presents as a wide range of illness from asymptomatic or mild to severe disease and death. People who are sick with flu and covid-19 often feel some or all of these symptoms like fever, cough, sore throat, runny or stuffy nose, headache, fatigue, and loss of taste. Some people may have vomiting and diarrhea, though this is more common in children than adults. Both viruses are transmitted by contact, droplets and fomites (objects or materials which are likely to carry infection, such as clothes, utensils, and furniture).
However, there are some important differences between covid-19 and influenza. First, as per WHO, covid-19 does not spread as efficiently as influenza. The serial interval (the time between successive cases) for covid-19 virus is estimated to be 5-6 days, while for influenza virus, the serial interval is 3 days. This means that influenza can spread faster than covid-19.
According to WHO, the symptoms of flu appear sooner than the SARS-CoV-2 virus. Influenza has a shorter median incubation period (the time from infection to appearance of symptoms) than covid-19 virus. The symptoms for covid-19 can develop between 1–14 days on the other hand; flu can develop in 3-4 days. Symptoms like shortness of breath, and respiratory issues are common in covid-19 whereas body ache, headache, loss of appetite, and feeling of chills are more common in seasonal flu. Based on data, it appears that it is more common for adults to pass the SARS-CoV-2 infection onto children and youngsters are less likely to develop symptoms.
As per the data, global death rate for covid-19 so far is 3.4%; on the other hand, it is less than 1% for seasonal flu. Therefore, the mortality rate for covid-19 is more than seasonal flu. While many people globally have built up immunity to seasonal flu strains, covid-19 is a new virus to which no one has immunity which means more people are susceptible to infection, and some may suffer severe disease.
Vaccination has been shown to have many benefits including reducing the risk of flu illnesses, hospitalizations and even the risk of flu-related death in children. As the flu has been around longer, there are several effective antiviral treatments and vaccines available. An annual seasonal flu vaccine is the best way to help protect against flu. One should get a flu vaccine before flu viruses begins spreading in your community, since it takes about two weeks after vaccination for antibodies to develop in the body and provide protection against flu. A flu vaccine is needed every season for two reasons. First, a person’s immune protection from vaccination declines over time, so an annual vaccine is needed for optimal protection. Second, because flu viruses are constantly changing, flu vaccines may be updated from one season to the next to protect against the viruses that research suggests may be most common during the upcoming flu season. There is no evidence that getting a flu vaccine increases the risk of getting covid-19. There are many benefits from flu vaccination and preventing flu is always important, but in the context of the covid-19 pandemic, it’s even more important to do everything possible to reduce illnesses. Scientists are developing vaccines for covid-19, but treatments and vaccines are not likely to be available soon.
The best way to prevent covid-19 and flu is to practice social distancing, which means avoiding any non-essential social contact or travel. It is essential to maintain good personal and domestic hygiene by washing the hands regularly and keeping surfaces and utensils clean. Also a good respiratory hygiene by coughing into your elbow or into a tissue and immediately disposing of the tissue should be practiced.
When to seek emergency medical attention
If someone is showing any of these signs like trouble breathing, persistent pain or pressure in the chest, and inability to stay awake seek emergency medical care immediately.