Coronavirus (COVID-19): Symptoms, Treatment & Prevention

What Are the Symptoms of COVID-19?

COVID-19 symptoms often resemble a common cold or flu. The most common symptoms include runny nose, nasal congestion, fever, sore throat, headache, changes in smell and taste, cough, difficulty breathing, and body aches. Most people experience mild symptoms and feel better within a few days.

COVID-19 affects people differently, and the severity of symptoms can vary widely from person to person. While some individuals experience barely noticeable symptoms, others may develop more significant illness. Understanding the range of possible symptoms helps you recognize the infection early and take appropriate action to protect yourself and others.

The virus primarily targets the respiratory system, which explains why many symptoms involve the nose, throat, and lungs. However, COVID-19 can also cause systemic symptoms that affect the entire body, such as fatigue, muscle aches, and fever. The immune response to the virus triggers inflammation that can manifest in various ways throughout the body.

Research has shown that the presentation of COVID-19 has evolved over time as new variants have emerged and population immunity has increased through vaccination and prior infection. Earlier variants often caused more severe respiratory symptoms, while more recent strains tend to cause symptoms more similar to the common cold in most people.

Common Symptoms of COVID-19

Here are the symptoms most frequently reported by people with COVID-19. You may experience one or several of these symptoms:

• Runny nose and nasal congestion - similar to a cold
• Fever - temperature above 38C (100.4F)
• Sore throat - pain or scratchiness when swallowing
• Headache - can range from mild to severe
• Loss of smell and taste - a distinctive symptom of COVID-19
• Cough - usually dry, but can produce mucus
• Difficulty breathing - shortness of breath with activity
• Body aches - muscle pain and fatigue

The vast majority of people experience mild symptoms and feel better after a few days. It is common to have some lingering symptoms such as mild runny nose or light cough for some time after recovering from COVID-19. Some people experience other symptoms as well, such as fatigue, pain, or mild breathing difficulties for up to several weeks.

Loss of Smell and Taste

One of the most distinctive features of COVID-19 is the sudden loss of smell (anosmia) and taste (ageusia). This symptom became well-known during the pandemic because it occurs much more frequently with COVID-19 than with other respiratory infections. The loss can be partial or complete and may occur even in people with otherwise mild symptoms.

Scientists believe the virus damages the olfactory neurons or supporting cells in the nasal passages, temporarily disrupting the sense of smell. For most people, smell and taste return within a few weeks, but some experience prolonged loss lasting months. Research continues into treatments for persistent smell loss, with smell training showing some promise as a rehabilitation technique.

Symptoms in Children

Children typically experience milder symptoms than adults when infected with COVID-19. Many children have no symptoms at all or only very mild cold-like symptoms. Serious illness from COVID-19 is rare in children, though it can occur. Parents should be aware that children can still spread the virus to others, including more vulnerable family members, even if they seem healthy.

In rare cases, children may develop a condition called Multisystem Inflammatory Syndrome in Children (MIS-C) weeks after a COVID-19 infection. This serious condition involves inflammation of various organs and requires immediate medical attention. Symptoms include persistent fever, abdominal pain, vomiting, rash, and extreme tiredness.

How Does COVID-19 Spread?

COVID-19 spreads primarily through respiratory droplets released when an infected person breathes out, coughs, sneezes, laughs, or sings. The risk of transmission is higher in crowded spaces with inadequate ventilation. You can also become infected by touching contaminated surfaces and then touching your nose, mouth, or eyes.

Understanding how COVID-19 spreads is essential for protecting yourself and others. The SARS-CoV-2 virus is highly transmissible, which contributed to its rapid global spread. The primary mode of transmission is through respiratory particles that an infected person releases into the air. These particles range in size from larger droplets that fall quickly to the ground to smaller aerosols that can linger in the air for extended periods.

When an infected person breathes, talks, coughs, or sneezes, they release these virus-containing particles into the surrounding environment. People nearby can become infected by inhaling these particles directly. The risk of transmission increases significantly in indoor settings with poor ventilation, where aerosols can accumulate over time. This explains why outbreaks often occur in settings like restaurants, gyms, and indoor gatherings.

Close contact with an infected person carries the highest risk of transmission. The World Health Organization defines close contact as being within approximately one meter (three feet) of an infected person for an extended period. However, in poorly ventilated spaces, transmission can occur at greater distances as aerosols spread throughout the room.

When Are You Contagious?

One of the challenging aspects of COVID-19 is that you can transmit the virus before you develop symptoms and realize you are sick. Studies have shown that a significant proportion of transmission occurs during this presymptomatic phase. You can also spread the virus even if you only feel slightly unwell, which underscores the importance of staying home at the first sign of illness.

Most people with COVID-19 are no longer contagious after five days from symptom onset, provided their symptoms are improving and they have been fever-free for at least 24 hours without using fever-reducing medication. However, if you have a severely weakened immune system due to illness or treatment, you may be contagious for a longer period. Your healthcare provider can advise you on precautions specific to your situation.

Can You Get COVID-19 More Than Once?

Yes, you can get COVID-19 multiple times. Having had COVID-19 provides some protection against getting sick again, but this protection decreases over time. The virus also changes (mutates), creating new variants that can partially evade immunity from previous infections. This is why booster vaccinations are recommended, particularly for people at higher risk of severe illness.

Reinfections tend to be milder than initial infections, especially in vaccinated individuals, because the immune system retains some memory of the virus and can mount a faster response. However, even mild reinfections can be inconvenient and carry some risk of complications, including long COVID.

Should I Stay Home When Sick?

Yes, staying home when you feel sick reduces the risk of spreading infection to others. Stay home until you feel better and have been fever-free for at least 24 hours without fever-reducing medication. This applies to all respiratory illnesses, not just COVID-19.

The decision to stay home when experiencing symptoms is one of the most effective ways to prevent disease transmission in your community. This simple measure protects your coworkers, classmates, family members, and others you might encounter during your daily activities. The concept of staying home while sick has gained renewed importance since the COVID-19 pandemic highlighted how easily respiratory viruses spread.

When you are infected with a respiratory virus like SARS-CoV-2, your body sheds viral particles with every breath, cough, and sneeze. Being in close contact with others during this time significantly increases their risk of infection. By staying home, you create a barrier that prevents these viral particles from reaching others who might be more vulnerable to severe illness.

The economic and social pressures to continue working or attending school while sick are real challenges that many people face. However, the cost of spreading illness often outweighs the short-term inconvenience of staying home. Workplaces and schools increasingly recognize the value of sick leave policies that encourage people to recover fully before returning.

When Can Children Return to School?

Children can return to daycare, school, or other activities when they are well enough to manage their normal daily routine. This includes children who still have mild symptoms such as a slight runny nose or light cough. Children who are physically active may cough more when moving around without this indicating they have become sick again.

The child should be able to participate in a group setting for a full day and engage in regular activities. They should also have been fever-free for 24 hours without taking fever-reducing medication. This waiting period ensures the fever has truly resolved rather than being suppressed by medication. A child may seem energetic in the morning but still lack the stamina for a full day of activities in a group setting.

Who Is at Higher Risk of Severe COVID-19?

People at higher risk of severe COVID-19 include older adults (especially those over 65), people with weakened immune systems, and those with chronic conditions such as heart disease, diabetes, chronic lung disease, obesity, and kidney disease. Vaccination is particularly important for these groups.

While COVID-19 can affect anyone regardless of age or health status, certain groups face a significantly higher risk of developing severe illness, requiring hospitalization, or experiencing life-threatening complications. Understanding these risk factors helps individuals take appropriate precautions and make informed decisions about vaccination and medical care.

Age is the strongest risk factor for severe COVID-19. The risk of hospitalization and death increases substantially with each decade of life, particularly after age 65. This increased vulnerability relates to both the normal aging of the immune system (immunosenescence) and the higher prevalence of chronic health conditions among older adults. Studies consistently show that the oldest populations bear the greatest burden of severe COVID-19 outcomes.

People with weakened immune systems, whether due to medical conditions like HIV/AIDS, cancer, or organ transplants, or due to immunosuppressive medications, face elevated risks from COVID-19. Their immune systems may be less capable of controlling the viral infection, leading to higher viral loads, prolonged illness, and greater risk of complications. These individuals may also have reduced responses to vaccination, making additional protective measures important.

Chronic Conditions That Increase Risk

Several chronic health conditions have been identified as increasing the risk of severe COVID-19:

• Cardiovascular disease - including heart failure, coronary artery disease, and cardiomyopathy
• Diabetes - both type 1 and type 2, especially if poorly controlled
• Chronic lung disease - including COPD, asthma, cystic fibrosis, and pulmonary fibrosis
• Chronic kidney disease - particularly those on dialysis
• Obesity - BMI of 30 or higher significantly increases risk
• Neurological conditions - including dementia and stroke history
• Liver disease - including cirrhosis and chronic hepatitis

Protecting High-Risk Individuals

If you or someone in your household is at higher risk for severe COVID-19, several strategies can help reduce exposure and protect health. Staying up to date with recommended vaccinations is the most important protective measure. Vaccines significantly reduce the risk of severe illness, hospitalization, and death, even against newer variants.

High-risk individuals may also benefit from antiviral medications if they do become infected. These medications work best when started early in the illness, so it is important to have a plan in place for rapid testing and access to treatment. Talk to your healthcare provider about whether antiviral treatment would be appropriate for you and how to access it quickly if needed.

What Can I Do Myself If I Get Sick?

For mild COVID-19, focus on rest, staying hydrated, and managing symptoms with over-the-counter medications. Drink plenty of fluids, especially if you have fever or cough. Use saline drops or decongestants for nasal congestion, and pain relievers for fever and body aches. Alternate between rest and gentle movement as you feel able.

Most people with COVID-19 will recover at home without needing specific medical treatment. The illness typically runs its course within one to two weeks, during which time supportive care focuses on managing symptoms and helping your body fight the infection. Understanding how to care for yourself or a family member at home can make the recovery process more comfortable.

Rest is essential for recovery from any viral infection, including COVID-19. Your body needs energy to mount an effective immune response against the virus. Listen to your body and rest when you feel tired. However, complete bed rest is not necessary and can even be counterproductive. As soon as you feel able, try to get up and move around periodically.

Staying hydrated is particularly important when you have fever or cough. Fever increases fluid loss through sweating, while coughing can be more irritating when airways are dry. Aim to drink more fluids than usual, including water, tea, broth, and other non-alcoholic beverages. If eating feels difficult, try to consume at least some food to maintain your strength.

Managing Specific Symptoms

Fever and Body Aches

Fever is not necessarily harmful and represents your body's natural response to infection. However, if you feel uncomfortable or unwell from the fever, you can take over-the-counter fever reducers. Paracetamol (acetaminophen) is generally the first choice and is safe for most people, including pregnant women. Children aged 3 months and older can receive appropriate doses of paracetamol, while children 6 months and older can also take ibuprofen.

Children and adolescents under 18 should not take medications containing aspirin (acetylsalicylic acid) for fever without first consulting a doctor, due to the risk of a rare but serious condition called Reye's syndrome.

Nasal Congestion

A blocked nose can be uncomfortable and interfere with sleep. Saline nasal drops or sprays can help thin mucus and relieve congestion. Decongestant sprays or drops that reduce swelling in the nasal passages are available over the counter but should not be used for more than 10 consecutive days to avoid rebound congestion. For infants, saline drops are the safest option.

Sore Throat

Sipping warm or cold drinks can soothe a sore throat. Try tea, ice cream, or yogurt. Sugar-free throat lozenges can also provide temporary relief. Various medicated throat sprays and lozenges are available at pharmacies for more significant throat pain.

Cough

Staying well hydrated helps manage cough symptoms. Keep a glass of water nearby, especially when trying to sleep. Over-the-counter cough medications are available, though their effectiveness is uncertain. Some people find them helpful. Avoid smoking and secondhand smoke, which can worsen coughing.

Rest and Movement

While rest is important, try to alternate between resting and gentle movement as your condition allows. When lying down:

• Move your legs and feet periodically to promote circulation
• Change positions from side to side
• Sit up or stand when you feel able

As you start feeling better, try to spend time outdoors and move around more. Pay attention to what your body can handle and gradually increase activity as you recover.

Creating a Comfortable Environment

Sleeping with your head elevated on extra pillows can make breathing easier, especially if you have nasal congestion or cough. Keeping the bedroom cool and well-ventilated can also improve comfort and sleep quality. Open a window or lower the thermostat to create a cooler sleeping environment.

When Should I Seek Medical Care?

Seek medical care if you become short of breath when moving around or are so exhausted you have difficulty staying up. Seek emergency care immediately if you have difficulty breathing at rest, experience sudden severe worsening, or feel extremely weak. Most people with COVID-19 do not need professional medical care.

The vast majority of people with COVID-19 recover at home without needing to see a doctor. The illness typically resolves on its own within one to two weeks. However, recognizing when symptoms require professional evaluation is important, particularly for those at higher risk of complications.

Contact a healthcare provider if you experience:

• Shortness of breath when moving around
• Extreme fatigue making it difficult to stay up
• Symptoms that persist or worsen after several days
• Concerns about your condition, especially if you are in a high-risk group

These recommendations apply even if you have been vaccinated against COVID-19. Vaccination greatly reduces the risk of severe illness but does not eliminate it entirely.

How Is COVID-19 Tested and Diagnosed?

COVID-19 is diagnosed through laboratory tests, including PCR tests (most accurate) and rapid antigen tests (convenient for home use). PCR tests detect viral genetic material from nasal or throat swabs. Rapid tests can provide results in 15-30 minutes but are less sensitive than PCR tests, especially early in infection.

Testing plays an important role in managing COVID-19, both for individual patient care and for public health monitoring. While testing is no longer required for most people with mild symptoms, it can be helpful for those at higher risk who might benefit from antiviral treatment, and for understanding the cause of illness in certain situations.

Most people do not need to be tested or examined by a healthcare provider. However, some individuals may benefit from knowing whether their symptoms are caused by COVID-19 or another illness, such as influenza. Testing is typically done by collecting a saliva sample or using a thin swab to collect a sample from inside the nose.

Types of COVID-19 Tests

PCR (Polymerase Chain Reaction) tests are the most accurate type of COVID-19 test. These laboratory tests detect the genetic material of the virus and can identify infection even when viral levels are relatively low. Results typically take one to three days. PCR tests are usually performed at healthcare facilities or testing centers.

Rapid antigen tests can be purchased at pharmacies and performed at home. These tests detect proteins on the surface of the virus and provide results within 15-30 minutes. While convenient, they are less sensitive than PCR tests, meaning they may miss some infections, particularly in the early stages or when viral levels are low. A negative rapid test does not completely rule out COVID-19.

Some healthcare providers may also order blood tests to check for signs of inflammation, assess organ function, or look for antibodies, depending on the clinical situation.

How Is COVID-19 Treated?

Most COVID-19 cases resolve without specific treatment. For high-risk individuals, antiviral medications like Paxlovid can shorten illness duration and reduce the risk of hospitalization if started within 5 days of symptom onset. Antibiotics do not work against COVID-19 because it is caused by a virus, not bacteria. Severe cases may require hospital care with oxygen therapy and other supportive treatments.

The treatment approach for COVID-19 depends on the severity of illness and the individual's risk factors for complications. For the majority of people who experience mild to moderate symptoms, treatment focuses on managing symptoms and allowing the body's immune system to clear the infection naturally. This supportive care approach includes rest, hydration, and over-the-counter medications for symptom relief.

Medical science has made significant advances in treating COVID-19 since the beginning of the pandemic. While there is still no cure, several effective treatments now exist that can reduce the severity and duration of illness, particularly for those at higher risk of complications.

Antiviral Medications

Antiviral medications work by interfering with the virus's ability to replicate in the body. When started early in the course of illness, these medications can shorten the duration of symptoms and significantly reduce the risk of hospitalization and death in high-risk individuals.

The most widely used antiviral for COVID-19 is nirmatrelvir-ritonavir (Paxlovid), which is taken as pills for five days. To be effective, treatment should begin within five days of symptom onset. Your healthcare provider can assess whether antiviral treatment is appropriate for you based on your risk factors and the timing of your illness.

It is important to note that antiviral medications are generally reserved for people at higher risk of severe illness. Most healthy individuals with mild COVID-19 do not need antiviral treatment and will recover well with supportive care alone.

Why Antibiotics Don't Help

Antibiotics are designed to fight bacterial infections and have no effect on viruses, including SARS-CoV-2. Taking antibiotics for a viral infection is not only ineffective but can contribute to antibiotic resistance, a growing global health threat. Antibiotics may only be prescribed if a bacterial infection develops as a secondary complication of COVID-19.

Hospital Treatment

While uncommon, some people with COVID-19 become seriously ill and require hospital care. Hospital treatment may include:

• Oxygen therapy - supplemental oxygen delivered through nasal prongs or a mask
• Intravenous fluids - to maintain hydration and deliver medications
• Anti-inflammatory medications - corticosteroids like dexamethasone for severe cases
• Antiviral medications - intravenous options for hospitalized patients
• Intensive care - mechanical ventilation for respiratory failure in critical cases

What Are the Complications of COVID-19?

COVID-19 can lead to pneumonia, respiratory failure requiring hospitalization, and in severe cases, multi-organ damage. Long COVID affects some people with persistent symptoms lasting weeks to months after infection. Serious complications in children are rare, but a condition called MIS-C can occur and requires immediate medical attention.

While most people recover from COVID-19 without lasting effects, the illness can sometimes lead to complications that require medical attention or result in prolonged health issues. Understanding potential complications helps individuals recognize warning signs and seek appropriate care when needed.

The respiratory system is most commonly affected by COVID-19 complications. The virus can cause inflammation in the lungs that progresses to pneumonia, making it difficult for oxygen to reach the bloodstream. In severe cases, this can lead to acute respiratory distress syndrome (ARDS), a life-threatening condition requiring intensive care.

Pneumonia and Respiratory Complications

COVID-19 pneumonia differs from typical bacterial pneumonia in several ways. It often affects both lungs and can cause widespread inflammation that takes longer to resolve. Even after the acute infection clears, some people experience ongoing respiratory symptoms such as shortness of breath, reduced exercise tolerance, and persistent cough. Most of these symptoms improve over time, but recovery can take several months.

Long COVID (Post-COVID Condition)

For some people, COVID-19 symptoms persist or new symptoms develop weeks or months after the initial infection. This condition, known as Long COVID or post-COVID condition, can affect people who had mild initial illness as well as those who were severely ill. Common symptoms include:

• Persistent fatigue that interferes with daily activities
• Difficulty concentrating or "brain fog"
• Shortness of breath or breathing difficulties
• Muscle or joint pain
• Ongoing loss of smell or taste
• Sleep problems
• Heart palpitations

Research into Long COVID continues, and understanding of this condition is evolving. If you experience persistent symptoms after COVID-19, talk to your healthcare provider about evaluation and management options. Read more about Long COVID recovery

Complications in Children

Serious COVID-19 complications in children are uncommon. However, some children who have had COVID-19 may develop Multisystem Inflammatory Syndrome in Children (MIS-C), usually 2-6 weeks after infection. This serious condition involves inflammation affecting multiple organ systems and requires immediate medical care. Warning signs include persistent fever, severe abdominal pain, vomiting, rash, bloodshot eyes, and extreme tiredness.

COVID-19 During Pregnancy and Breastfeeding

Pregnant individuals with mild COVID-19 symptoms generally do not need to seek medical care unless they have other conditions that increase their risk. The baby in the womb is not infected if the mother has COVID-19. Most pregnant people can deliver normally, though severe illness may require cesarean section. Breastfeeding is safe during COVID-19 infection.

Pregnancy brings unique considerations when it comes to COVID-19. Research has shown that pregnant individuals are at somewhat higher risk of severe COVID-19 compared to non-pregnant individuals of similar age. This increased risk underscores the importance of vaccination during pregnancy, which is safe and recommended.

If you are pregnant and develop mild COVID-19 symptoms, you generally do not need to seek medical care. However, if you have conditions that increase your risk of severe illness, such as diabetes, high blood pressure, or obesity, contact your prenatal care provider for guidance. In some areas, pregnant individuals with symptoms are recommended to get tested for COVID-19.

Does COVID-19 Affect the Baby?

Current evidence indicates that the SARS-CoV-2 virus does not cross the placenta to infect the baby during pregnancy. Babies are not born with COVID-19 infection from their mothers, though they can potentially acquire the infection after birth through close contact.

Most pregnant people with COVID-19 can deliver vaginally as planned. However, if you become severely ill with COVID-19 during pregnancy, your healthcare team may recommend cesarean delivery to protect your health and the baby's health.

Breastfeeding and COVID-19

You can safely breastfeed your baby even if you have COVID-19. The virus has not been shown to transmit through breast milk, and breastfeeding provides important immune benefits for the infant. Taking basic hygiene precautions, such as washing hands before feeding and wearing a mask if you have respiratory symptoms, can help reduce the risk of spreading the virus to your baby through respiratory droplets.

Vaccination During Pregnancy

COVID-19 vaccination is recommended during pregnancy. Studies have shown that vaccines are safe for pregnant individuals and provide protection against severe illness for both mother and baby. Antibodies from vaccination can cross the placenta and provide some protection to newborns in their first months of life.

How Can I Prevent COVID-19?

Prevent COVID-19 by washing hands frequently with soap and water, avoiding touching your face, staying home when sick, practicing respiratory hygiene (cough into elbow), ensuring good ventilation in indoor spaces, and staying up to date with vaccinations. These measures also reduce transmission of other respiratory infections.

Prevention strategies for COVID-19 have evolved as we've learned more about the virus and as population immunity has increased through vaccination and natural infection. While the risk of severe illness has decreased for most people, basic hygiene measures remain valuable for reducing transmission of COVID-19 and other respiratory infections.

The most effective prevention measure is vaccination. COVID-19 vaccines have proven highly effective at preventing severe illness, hospitalization, and death. While vaccines may not prevent all infections, they significantly reduce the risk of serious outcomes. Staying up to date with recommended boosters is particularly important for those at higher risk of complications.

Hand Hygiene

Frequent handwashing remains one of the simplest and most effective ways to prevent infection. Wash your hands thoroughly with soap and water for at least 20 seconds, especially:

• After being in public spaces
• After coughing, sneezing, or blowing your nose
• Before eating or preparing food
• After using the bathroom
• After touching surfaces that many people contact

When soap and water are not available, use hand sanitizer containing at least 60% alcohol. Apply enough to cover all surfaces of your hands and rub until dry.

Respiratory Hygiene

Practice good respiratory hygiene to prevent spreading viruses to others:

• Cough or sneeze into your elbow or a tissue
• Dispose of used tissues immediately in a trash bag
• Wash your hands after coughing, sneezing, or handling tissues
• Avoid close contact with others when you are sick

Ventilation and Indoor Air Quality

COVID-19 spreads more easily in indoor spaces with poor ventilation. When gathering with others, spending time outdoors reduces the risk of transmission because the virus disperses more quickly in open air. When indoors, opening windows, using fans, or ensuring HVAC systems are working properly can improve air circulation and reduce viral concentration in the air.

Vaccination

Vaccination remains the most important tool for preventing severe COVID-19. Current vaccines are effective against serious illness from circulating variants. Follow your healthcare provider's recommendations for initial vaccination and booster doses, which may vary based on your age, health status, and risk factors.