COVID-19 shares some similarities with other respiratory conditions, such as the common cold and influenza. However, there are also crucial differences.
Understanding how these conditions differ and how they spread can help people respond properly to each of them.
Similarities range from symptoms to causes to treatment options. It is worth noting, however, that there are also some key differences.
Keep reading to learn more about these conditions, including a breakdown of symptoms and recovery times.
The common cold is a common viral infection that many people experience, especially in the colder, winter months.
Major symptoms
Cold symptoms may come on gradually, meaning the person may slowly feel worse rather than have symptoms come on all at once.
Symptoms of the common cold include:
The Centers for Disease Control and Prevention (CDC) note that these symptoms are typically milder than the symptoms of the flu. People with colds are more likely to have a runny or stuffy nose compared with other infectious diseases, such as the flu.
Causes
Symptoms of the common cold appear due to a viral infection with one of many types of infectious viruses, such as human rhinoviruses.
Treatment
There is no cure for the common cold. Most people can effectively fight off the cold with supportive care and over-the-counter (OTC) medications.
Treatment generally focuses on easing symptoms as the body fights off the infection. This may include OTC drugs, such as:
- decongestants
- cough suppressants
- expectorants
- pain relievers
There is no vaccine for the common cold.
Some natural remedies may also help ease symptoms.
Recovery time
The CDC note that most people recover from a cold within 7–10 days. Some symptoms may linger longer than others.
People with weakened immune systems or other respiratory issues, such as asthma, may develop a serious illness, such as pneumonia or bronchitis, as a result.
Similarities to COVID-19
Both the common cold and COVID-19 spread mainly by droplets.
Both conditions have symptoms that come on gradually in response to the infection.
Some symptoms may be similar, such as feeling aches or fatigue. COVID-19 and the common cold may also cause a cough.
Differences from COVID-19
Symptoms of the cold tend to come on slowly and usually include a runny or stuffy nose, which are not as common in people with COVID-19.
The cough from a cold may be different as well. With the cold, this may be a response to postnasal drip, which generally does not occur in COVID-19.
Other signs, such as fever and shortness of breath, are not typically signs of the common cold.
The cold also does not usually cause digestive symptoms, such as diarrhea, nausea, or vomiting, which may occur with COVID-19 or the flu.
Some viruses that cause the common cold may survive on surfaces. COVID-19, on the other hand, appears to transmit mainly through contact with droplets.
The common cold is generally not serious, and most people clear the issue on their own while managing symptoms. By comparison, COVID-19 has a higher risk of serious or fatal complications.
Influenza, or flu, tends to be more severe than the common cold, but it shares some symptoms.
Symptoms
Influenza can cause mild to severe symptoms. They seem to come on quickly and can include:
- fever
- chills
- cough
- sore throat
- runny nose
- congestion
- muscle aches
- body aches
- headaches
- fatigue
Some people may also experience vomiting or diarrhea, although the CDC note that this is more common in children than in adults.
Causes
The symptoms of influenza appear as a result of an infection with influenza viruses in the nose, throat, and sometimes lungs.
Treatment
A viral infection causes the flu, so antibiotics used to treat bacterial infections will not help with symptoms.
The CDC recommend annual flu vaccines for anyone over the age of 6 months as the best preventative measure toward reducing the spread of the flu.
Some antiviral medications may help with symptoms in severe flu cases or in people who are at higher risk of serious symptoms from the flu. The CDC recommend starting them within 2 days of getting sick. That said, starting them later may still be helpful, especially for people in high risk groups.
Recovery time
The CDC note that some people will recover from the flu in a few days, and others may take up to 2 weeks.
Some people may develop severe complications, including pneumonia. Complications from the flu can be severe, and in some cases, they may even be life threatening.
Similarities to COVID-19
Both influenza and COVID-19 are contagious respiratory illnesses caused by viruses. Symptoms may be similar, and doctors may look to testing to help reveal or confirm their diagnosis.
Both the flu and COVID-19 spread mainly by droplets.
Both the flu and COVID-19 can cause complications, including life threatening issues, such as acute respiratory distress syndrome (ARDS) and respiratory failure.
Some groups are at higher risk of complications from both conditions, including:
- older adults
- people with some underlying medical conditions
- pregnant people
Differences from COVID-19
The CDC note that influenza does not appear to spread as easily as COVID-19. Flu symptoms may also show up sooner after infection.
The risk of complications in otherwise healthy children is higher with the flu compared with COVID-19.
A yearly flu vaccine may help prevent infection. Antiviral medications may also help people in at-risk groups avoid severe complications from the flu.
There are a number of therapeutic agents and vaccines in various stages of development for COVID-19.
According to the WHO, severe and critical infection rates appear lower for the flu compared with COVID-19. Similarly, the flu appears to be less fatal. Typically, below 0.1% of seasonal influenza cases are fatal.
An Imperial College London report notes that fatal cases of COVID-19, or infection fatality ratio, are at 1.15% in high income countries where the population is older, and 0.23% in lower income countries that tend to have a younger overall population.
The CDC recommend that people wear cloth face masks in public places where it is difficult to maintain physical distancing. This will help slow the spread of the virus from people who do not know that they have contracted it, including those who are asymptomatic. People should wear cloth face masks while continuing to practice physical distancing. Instructions for making masks at home are available here. Note: It is critical that surgical masks and N95 respirators are reserved for healthcare workers.
All data and statistics are based on publicly available data at the time of publication. Some information may be out of date.
COVID-19 has many similar symptoms to both the flu and the common cold. However, there are also some key differences.
Major symptoms
While noting that other symptoms are possible, the CDC list the following symptoms as being the most common:
- chills or fever
- cough
- shortness of breath or breathing difficulty
- fatigue
- body or muscle aches
- headache
- new loss of the sense of taste or smell
- sore throat
- stuffy or runny nose
- vomiting or nausea
- diarrhea
No two cases are the same. More severe symptoms may include:
- increased difficulty breathing or shortness of breath
- confusion
- inability to wake up or stay awake
- bluish lips, face, or skin
- needing to pant or gasp to catch the breath
- persistent pain in the chest
Severe symptoms are a sign to seek immediate medical care.
Causes
The COVID-19 disease develops as a result of an infection with SARS-CoV-2, a type of coronavirus. Other coronaviruses can cause the common cold.
The CDC note that COVID-19 spreads mainly through close contact with the respiratory droplets of a person with an infection. People with COVID-19 shed these droplets as they breathe, speak, laugh, or do other activities that may release bodily fluids from their airways.
Sometimes, COVID-19 can spread through airborne transmission. This can occur when respiratory secretions from a person with a SARS-CoV-2 infection stay suspended in the air for longer periods of time.
Treatment
Treatment for COVID-19 is complex and will vary depending on symptoms. Up to 80% of cases will resolve in the person’s home without the need for hospitalization or medical treatment.
Doctors may recommend ways to help manage symptoms and allow the body to heal naturally, including:
- taking pain medications, such as acetaminophen (Tylenol) or ibuprofen (Advil) to reduce fever and symptoms of pain
- drinking plenty of water to stay hydrated
- getting plenty of rest to allow the body to fight the virus
In cases of people who are at higher risk of severe symptoms but do not require hospitalization, doctors may recommend the person get medical treatment.
If the person requires hospitalization, treatment may focus on methods to slow the virus, reduce the overactive immune system, or treat or prevent complications.
These methods may vary in each case depending on symptoms, severity, and a person’s risk factors.
Recovery time
Recovery time for COVID-19 can vary widely from person to person based on factors such as severity and symptoms.
The CDC note that most people with COVID-19 recover and return to normal health. However, some people can have symptoms and complications that last for weeks or months after recovery from the illness.
Even people who recover from mild illness may have long-lasting symptoms.
The most commonly reported long-term symptoms include:
- fatigue
- cough
- shortness of breath
- chest pain
- joint pain
Other long-term effects are possible, including serious complications. The significance of these long-term effects is still unknown, and more will come to light as new data emerge.
Learn more about COVID-19 here.
COVID-19 occurs due to a viral respiratory infection. Since the virus attacks the respiratory system, COVID-19 may share some similarities with the common cold or influenza.
Differentiating COVID-19 from the common cold or flu can help people respond to each issue properly.
Anyone who is uncertain or concerned about their symptoms should contact a healthcare professional.
Anyone in high-risk groups who notices signs of respiratory sicknesses should also contact a doctor.