
It's been nearly two years since the world changed because of COVID-19 and while experts are still studying and learning about the virus, there are a few symptoms that are common and can appear in a certain order. COVID affects everyone differently, but there can be a pattern of signs that indicate you have the virus. Read the various ways COVID symptoms can happen—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.
The Order of Symptoms

Dr. Jagdish Khubchandani, MBBS, Ph.D. Professor of Public Health New Mexico State University explains, "There are tons of individual narratives and studies on symptom variety. However, there still seems to be a need for a consensus on what the first symptoms could be. The few studies that exist have indicated: Fever/chills>> cough> headache followed by sore throat, discomfort/malaise, seems to be the most logical and confirmed symptom patterns. Confirmed by different methods in the aforementioned studies, this pattern makes sense because an infection causes release of immune system related and inflammation markers in blood that would cause these symptoms (e.g. fever). Also, other coronaviruses that are responsible for seasonal colds have these symptom patterns."
What to Know About the COVID Patterns

Dr. Khubchandani says, "I caution that patterns should not be considered like rules of COVID-19 because many people may not keep track of what happened and when in relation to how symptoms started. Also, when the infection becomes symptomatic with worsening of symptoms, it could be a cluster of symptoms appearing simultaneously. One should always assume that you will mostly have a cluster of symptoms and sometimes, just one symptom (e.g. in some cases of a very mild infection). Breathing difficulties should definitely be considered an alarming symptom after a few days of initial fever and cough."
Watch Out for Multiple Symptoms at Once

Dr. Khubchandani states, "Clusters of symptoms can vary among individuals and outcomes could be influenced by age, having other diseases, vaccination status, immune system functioning, etc. Mortality then depends on type of care and speed of care received."
Examples of Clustered Symptoms

"A big multi-agency funded study from the UK has defined these clusters as the following, Dr. Khubchandani says.
- ('flu-like' with no fever): Headache, loss of smell, muscle pains, cough, sore throat, chest pain, no fever.
- ('flu-like' with fever): Headache, loss of smell, cough, sore throat, hoarseness, fever, loss of appetite.
- (gastrointestinal): Headache, loss of smell, loss of appetite, diarrhea, sore throat, chest pain, no cough.
- (severe level one, fatigue): Headache, loss of smell, cough, fever, hoarseness, chest pain, fatigue.
- (severe level two, confusion): Headache, loss of smell, loss of appetite, cough, fever, hoarseness, sore throat, chest pain, fatigue, confusion, muscle pain.
- (severe level three, abdominal and respiratory): Headache, loss of smell, loss of appetite, cough, fever, hoarseness, sore throat, chest pain, fatigue, confusion, muscle pain, shortness of breath, diarrhea, abdominal pain."
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When to Seek Medical Treatment

The Mayo Clinic states, "If you have COVID-19 signs or symptoms or you've been in contact with someone diagnosed with COVID-19, contact your health care provider right away for medical advice. Your health care provider will likely recommend that you get tested for COVID-19. If you have emergency COVID-19 symptoms, such as trouble breathing, seek care immediately. If you need to go to a hospital, call ahead so that health care providers can take steps to ensure that others aren't exposed.
If you have emergency COVID-19 signs and symptoms, seek care immediately. Emergency signs and symptoms can include:
- Trouble breathing
- Persistent chest pain or pressure
- Inability to stay awake
- New confusion
- Pale, gray or blue-colored skin, lips or nail beds — depending on skin tone
This list isn't complete. Let your health care provider know if you are an older adult or have chronic medical conditions, such as heart disease or lung disease, as you may have a greater risk of becoming seriously ill with COVID-19."
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How to Stay Safe Out There

Follow the public health fundamentals and help end this pandemic, no matter where you live—get vaccinated or boosted ASAP; if you live in an area with low vaccination rates, wear an N95 face mask, don't travel, social distance, avoid large crowds, don't go indoors with people you're not sheltering with (especially in bars), practice good hand hygiene, and to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.