Covid-19 - January 20, 2022

Covid-19 and the flu - similarities and differences

Covid-19 - January 20, 2022

With the rise of Omicron through the UK and symptoms being reported as similar to that of the common cold, many people are concerned about distinguishing between Covid-19 and the flu. In the UK, winter always presses demand on the NHS and with the uptick of Covid-19 cases, many people are concerned about their own health.

Coronavirus and the flu are both contagious respiratory illnesses. However, they are caused by different viruses (Covid-19 is caused by an infection called SARS-CoV-2 and the flu is caused by infection with influenza viruses). Many of the symptoms of these two viruses are shared and therefore it can be hard to tell the difference between the two, and will require a test to confirm diagnosis. In this article, we will explore how you can identify the differences and similarities between the flu and Covid-19.

Symptoms of Covid-19 and the flu

The ZOE COVID Study App have distinguished that the Omicron variant of Covid-19 presents symptoms such as:

  • Runny nose

  • Headache

  • Fatigue (mild or severe)

  • Sneezing

  • Sore throat

Certain symptoms are present in the flu as well, particularly a sore throat, headache and fatigue. Other variants of Covid-19 present other symptoms shared with the flu, such as a cough, fever, shortness of breath and muscle pain. 

When do symptoms of Covid-19 and the flu develop?

Symptoms of both Covid-19 and the flu can appear one or more days between a person being infected to when they start to experience symptoms. However, coronavirus symptoms can take longer to develop than those of the flu. The flu typically takes anywhere from 1 to 4 days after infection to develop systems, whereas Covid-19 symptoms develop typically 5 days after being infected, but can appear as early as 2 days after infection or even up to 14 days.

Both flu and Covid-19 can be spread by someone at least 1 day before experiencing any symptoms, and if someone has coronavirus they may be contagious for a longer period of time than if they had flu - however this is still under investigation. For the flu, adults appear to be more contagious during the initial 3-4 days of showing symptoms, but can remain contagious for up to 7 days. Infants and vulnerable people with weakened immune systems can be contagious to the flu for longer periods of time. Covid-19 can be spread up to 2 days before symptoms are exposed and can remain contagious for up to at least 10 days after symptoms first appear. It is even possible for people to spread Covid-19 who are asymptomatic or if their symptoms have declined after testing positive for at least 10 days. 

How do Covid-19 and the flu spread?

There are similarities between how the flu and Covid-19 are spread, such close contact from person-to-person, spread by droplets made when people who are infected cough, talk or sneeze. The droplets are then inhaled by others or can land in the mouth or nose. The illnesses can also be spread by people picking them up on surfaces that have previously been touched by someone infected, and then touching their face. However, even though both the flu and coronavirus are spread in similar ways, Covid-19 is more susceptible to people of certain ages and populations than the flu, and can be spread more quickly and easily to large numbers of people through super-spreaders. 

Certain people are at more high-risk for severe illness from both Covid-19 and flu, including pregnant people, people with underlying health conditions, and older adults. Flu is higher risk for healthy children compared to Covid-19, and children with underlying health conditions are at increased risk for both. 

How to manage Covid-19 and the flu?

For both illnesses, vaccines provide the best protection. With the rise in Omicron and colder weather, it is imperative that you are fully protected against Covid-19. A flu vaccine is also recommended to people falling into the following categories:

  • aged 65 years or over

  • living in a residential or nursing home

  • the main carer of an older or disabled person

  • a frontline health or social care worker

  • pregnant, see below

  • children of a certain age

Covid-19 Rapid Antigen Tests can detect whether your symptoms are due to Covid-19 and you should test prior to socialising and if you feel unwell.

Qured have diagnostic tests available on our website, we offer a pack of 25 tests for £5/test which should help see you through the colder months.

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