Difference between COVID and Flu

There are many similarities between COVID-19 and the flu, but the differences are significant enough to cause millions of deaths and send the world into a public health crisis. Although both illnesses are caused by infectious viruses that attack the respiratory system, the COVID-19 pathogen is more lethal because it is a novel virus (not previously seen in humans) and therefore more easily spread (infecting more people produces a higher number of deaths).

In addition to higher transmission rates, COVID-19 also may produce much more severe symptoms in some people such as those with comorbidities. Not only can this illness make it nearly impossible to breathe during the active infection in some, COVID-19 also appears to have long-term effects that can significantly diminish the quality of life for some patients regardless of the severity of the infection.

How the Viruses Differ

The virus that causes COVID-19 is the SARS-CoV-2, a coronavirus. Coronaviruses cause the common cold, but SARS-CoV-2 is more closely related to the virus that caused SARS than the common cold virus. In fact, the COVID-19 virus and the SARS virus share long, identical pieces of RNA.

There are some similarities between SARS-CoV-2 and the influenza virus. Namely, they are both RNA viruses that use surface proteins to infect hosts. This infection process involves using proteins on the outside of the virus envelope to bind to receptors on the outside of target cells. Upon binding, the virus enters the cell and hijacks the cell’s machinery to reproduce, eventually overwhelming and destroying the cell.

The SARS-CoV-2 virus has only one long strand of RNA, while the influenza virus has 8 strands of varying length. The multiple strands enable influenza viral strains to frequently exchange genetic material and produce new strains. In comparison, SARS-CoV-2 has a lower mutation rate.

Therefore flu vaccines must be adjusted every season; one or two strains projected to be dominant in the upcoming season must be identified and a targeted vaccine designed. On the other hand, a SARS-CoV-2 vaccine should remain effective for a much longer period since this virus doesn’t change quite as rapidly.

The Key Differences between the Two Illnesses

It is easy to mistake COVID-19 for the flu, which is why you should get tested or see your doctor if you suspect that you have COVID-19. There are some telltale signs that you may have COVID-19:

  • Loss of smell or taste—unlike the flu, COVID-19 may sometimes cause the loss of the sense of smell or taste.
  • No or mild symptoms—it may seem like a positive that many people who contract COVID-19 have no or only mild symptoms, but you should keep in mind that the people around you may not respond to infection in the same way.
  • Longer runup to symptoms—part of the difficulty of tracking and containing COVID-19 is that it takes longer for symptoms to show up than with the flu. You may be able to infect others during this runup period without symptoms which may range from 2 to 14 days. Flu symptoms will normally appear from 1 to 4 days after exposure.

It is important to keep in mind that you cannot differentiate between COVID-19 and the flu just based on symptoms alone because the two illnesses have very similar symptoms which include

  • Fever
  • Chills
  • Cough
  • Difficulty breathing
  • Fatigue
  • Runny nose
  • Sore throat
  • Headache
  • Body aches
  • Vomiting
  • Diarrhea

The only accurate way of determining if you have COVID-19 instead of the flu is to get tested.

How to Avoid Getting Sick

After almost two years of living with the COVID-19 pandemic, you have probably heard the most important ways to limit your exposure to airborne respiratory illnesses like COVID-19 and the flu, but because new information is always becoming available, you should be sure that you are up to date.

  • Stay away from the ill—if someone is showing signs of illness like coughing or runny nose, maintain a healthy distance from them. If you need to attend a social gathering, do so only with people you trust and, preferably, have been vaccinated against COVID-19.
  • Eat a healthy diet—your overall health has a great impact on how well your immune system performs, and one of the best ways to improve your health is eat nutritiously. Avoid too much sugar, fat, or sodium. Include lean protein, whole grains, fruits, and vegetables.
  • Vitamin D deficiency (40% of U.S. population) – Vitamin D preplacement is highly encouraged to help boost your immune system.
  • Manage your health conditions—one of the key risk factors for developing a severe case of COVID-19 is having a preexisting health condition like diabetes, asthma, or hypertension. If you are able, do your best to keep your health condition under control.
  • Keep your hands clean—because germs like the COVID-19 virus can survive on surfaces for up to 8 hours, you should mind what you touch. Wash your hands regularly and especially after touching any surface that comes into contact with multiple people. Use hand sanitizer if you cannot wash your hands immediately.
  • Exercise regularly—one very important way of improving your general health is to adopt a habit of exercising. Not only will this strengthen your respiratory and immune systems, but it should also help you stay at a healthy weight which can vastly increase your ability to fight off an infection.
  • Make time for sleep—make your nightly rest a priority because sleep is vital in recharging your immune system. The recommendation is 7-8 hours of sleep per night.  So, take steps to make your sleep as restful as possible both before you get sick and while you are ill.
  • Hydrate—most people ignore one of their bodies most important needs—for water. Make it a habit to carry around a water bottle so that you can constantly be topping yourself off. This should help you maintain an optimal immune system.
  • Stop bad habits—if you smoke or drink alcohol excessively, now is the ideal time to stop. Both materials are toxic and can damage your immune and respiratory systems, so indulging in either habit can make you vulnerable to infection.
  • Practice social distancing—maintain a minimum of 6 feet between yourself and others. If possible, wear a mask in public.

Article written by: Dr. Robert Moghim – CEO/Founder Colorado Pain Care

M.D. Disclaimer: The views expressed in this article are the personal views of Robert Moghim, M.D. and do not necessarily represent and are not intended to represent the views of the company or its employees.  The information contained in this article does not constitute medical advice, nor does reading or accessing this information create a patient-provider relationship.  Comments that you post will be shared with all visitors to this page. The comment feature is not governed by HIPAA, and you should not post any of your private health information.