COVID-19 and the flu can cause similar symptoms. However, there are several differences between them.

The novel strain of coronavirus (SARS-CoV-2) causes coronavirus disease 19 (COVID-19).

Both COVID-19 and the flu are respiratory illnesses that spread from person to person. This article will discuss the differences between COVID-19 and the flu.

Symptoms

The symptoms of the flu and COVID-19 have some differences.

People who have the flu will typically experience symptoms within 1–4 days. The symptoms for COVID-19 can develop between 1–14 days. However, according to 2020 research, the median incubation period for COVID-19 is 5.1 days.

As a point of comparison, the incubation period for a cold is 1–3 days.

The symptoms of COVID-19 are similar in both children and adults. However, according to the Centers for Disease Control and Prevention (CDC), children typically present with fever and mild, cold-like symptoms, such as a runny nose and a cough.

The following table outlines the symptoms of COVID-19, the flu, and a cold.

Severity and mortality

The symptoms of COVID-19 and flu can range from mild to severe. Both can also cause pneumonia.

It is important to note that the World Health Organization (WHO) have classified mild symptoms of COVID-19 to mean that a person will not require hospitalization. The WHO classify mild cases to consist of symptoms including:

  • fever
  • cough
  • fatigue
  • loss of appetite
  • nasal congestion
  • sore throat
  • headache

According to the WHO, around 15% of COVID-19 cases are severe, and 5% are critical. Those in a critical state require a ventilator to breathe. The chance of severe and critical infection is higher with COVID-19 than the flu.

COVID-19 is also more deadly. According to the WHO, the mortality rate for COVID-19 appears to be higher than that of the flu.

Compared with the flu, research on COVID-19 is still in its early stages. These estimates may change over time.

Transmission

Both SARS-CoV-2 and the flu virus can spread through person to person contact.

Tiny droplets containing the viruses can pass from someone with the infection to someone else, typically through the nose and mouth through coughing and sneezing.

The virus can also live on surfaces. The WHO is not sure exactly how long the virus can survive, but it could be days.

According to the CDC, people can transmit the flu virus to people who are 6 feet (ft) away. According to the WHO, people should stay at least 6 ft away from anyone coughing or sneezing to help prevent the transmission of the SARS-CoV-2 infection.

According to the WHO, the speed of transmission differs between the two viruses. The symptoms of flu appear sooner, and it can spread faster than the SARS-CoV-2 virus.

The organization also indicate that people with flu can pass the virus on before they show any symptoms. A person can also pass on the SARS-CoV-2 infection even if they have no symptoms.

There are also differences in transmission between children and adults.

According to the WHO, the transmission of the flu from children to adults is common. However, based on early data it appears that it is more common for adults to pass the SARS-CoV-2 infection onto children. Children are less likely to develop symptoms.

Medical reference: Medical News Today