Maybe you’ve been in a room recently with someone who’s coughing, but they say “I promise it’s not COVID.” While it’s important to still be cautious about COVID-19, there are other viral respiratory infections that can still be passed between people.
Our bodies are always working hard to fight off infections, including those caused by viruses. While different types of viruses can affect different parts of the body, they often affect the respiratory system, which is the group of tissues and organs that allows us to breathe. The average set of lungs breathes in about 2,000 gallons of air every day, and viruses in the respiratory system can cause some of the classic symptoms of a cold or the flu.
There are two different parts of the respiratory system that can be affected by viruses: the upper and lower respiratory tracts.
The upper part of the respiratory tract includes:
— The nose
— Nasal cavities
— Mouth
— Throat
— Voice box or larynx
The lower respiratory tract includes:
— The windpipe, also known as the trachea
— Bronchi, airways that branch off the trachea that circulate air in and out of the lungs
— Lungs
[READ: A Patient’s Guide to Respiratory Disease.]
Respiratory Viral Infections
There are about 200 viruses known to cause disease in humans, says pediatric nurse practitioner Maryanne Tranter, founder of The Healthy Child Concierge.
Our respiratory system is especially vulnerable to certain viruses that can cause a cold, flu and other illnesses. A viral respiratory infection refers to a virus that specifically affects the upper or lower respiratory tracts, or both.
Typically, viral infections are passed via respiratory droplets, which are microscopic drops of mostly water that are produced when someone coughs, sneezes or talks. The viruses in these droplets are generally thought to be contagious if you’re within 6 feet of the person who produces them. Viruses in droplets can live on surfaces for several hours, and you can get sick from touching those surfaces.
Those droplets, if coming from someone who is sick, can immediately start to infect and multiply in our cell linings, says Dr. Sudeb Dalai, an infectious disease specialist and clinical assistant professor with the Division of Infectious Diseases and Geographic Medicine at Stanford University Medical Center in Palo Alto, California.
While the viruses that affect the respiratory system almost all have a similar structure, they also are all seasonal, meaning that they emerge and make people sick during certain times of the year, Dalai says.
Viruses can affect the respiratory system differently depending on where they initially attack. For instance, when a virus affects the lungs and airways, it can make breathing harder and cause wheezing, adds Dr. Tina Q. Tan, an attending physician of infectious diseases?at Ann & Robert H. Lurie Children’s Hospital of Chicago and a professor of pediatrics at Northwestern University Feinberg School of Medicine.
A virus that’s in the nose and nasal cavities can make you feel stuffy. Sometimes, these infections can affect other parts of the body. For instance, upper respiratory viral infections also can cause a viral ear infection, Tan says. An infection can cause the eustachian tube that connects the ears and throat to become swollen or irritated, so fluid can’t drain out of the ear properly, which can result in an ear infection.
There are many types of viruses that can lead to a respiratory viral infection. Four of the most common types of infections include:
— Common cold
— Flu
— COVID-19
— Respiratory syncytial virus
Common cold
The common cold is not caused by just one virus. In fact, it can be caused by hundreds of different viruses, Tan says. Some of the viruses associated with the common cold include:
— Coronaviruses. This is a large family of viruses, with one member that might be most notorious for the illness that causes COVID-19. Four types are common and cause mild to moderate respiratory infections, like the common cold.
— Enteroviruses. Infections caused by enteroviruses are more common in the summer and fall, according to the Centers for Disease Control and Prevention. In addition to the common cold, the enterovirus can potentially cause other health problems, such as low oxygen in the blood and conjunctivitis (a type of eye infection), according to the Enterovirus Foundation.
— Rhinoviruses. “Rhino” as a prefix means nose, so it may be no surprise that these types of infections are thought to be the cause of 30% to 35% of all common colds, according to the National Institutes of Health.
Symptoms associated with the common cold include:
— A runny nose
— Congestion
— Cough
— A sore throat
— Feeling more tired
— A fever
— Losing your voice (laryngitis)
A cold is usually diagnosed with a history and exam performed by a health professional. However, many colds are managed at home without a formal diagnosis.
There’s no cure for a cold. That’s why drinking fluids, resting, staying home and using pain relievers or medicines to help your congestion as needed are usually the best way to get over a cold.
[READ: Allergies or Cold: What’s the Difference?]
Flu
Like the common cold, flu isn’t caused by just one type of virus. It’s primarily caused by viruses called influenza type A or influenza type B. The exact virus that causes most flu in any given flu season is a usually a subtype of influenza A or B.
The most common flu symptoms include:
— A fever of 100.4 F or higher
— Chills or feeling overheated
— Congestion or a runny nose
— Cough
— Fatigue
— Headache
— Muscle ache
Not everyone who has the flu gets it diagnosed. However, those who do see a doctor for the flu may take one of several tests that help pinpoint that it’s the flu, according to the CDC. The results are available in as little as 15 minutes or in a few hours, depending on the test.
Those who are at higher risk for the flu and who suspect they have it should get tested for it, the CDC advises. That’s because they are more prone to flu complications. Higher-risk populations include:
— Adults age 65 and older
— Children
— People with chronic conditions, such as asthma, diabetes and heart disease
— Pregnant women
Doctors may run tests to rule out other types of infections that have symptoms similar to the flu, Dalai says.
There are antiviral treatments for the flu that can reduce the number of days you are sick and help prevent serious flu complications, such as pneumonia, the CDC reports. Additionally, rest and maintaining a good fluid intake will help.
Getting the flu vaccine each year can help lower your risk and is effective 40% to 60% of the time, according to the CDC. That percentage can vary each year. Flu vaccines are important for people of all ages, as flu can lead to death. In the 2023-2024 flu season, an estimated 44,900 people died from flu complications, the CDC reports.
[READ: Best Foods to Eat for a Cold or Flu: Expert Advice]
COVID-19
SARS-CoV-2 or COVID-19 is caused by one strain of coronavirus, while other coronaviruses may cause just a common cold. Symptoms of COVID-19 usually appear within 2 to 14 days after exposure and include:
— A fever
— Chills
— Congestion or a runny nose
— Cough
— Digestive symptoms, such as diarrhea
— Fatigue
— Headache
— Muscle pain
— Sore throat
You should call 911 or go to an emergency room if you or someone you know has COVID and is experiencing confusion, is unable to wake up or stay awake, has persistent chest pressure or trouble breathing or if their lips, nail beds or skin appear blue.
Treatments for COVID include two antiviral pills: nirmatrelvir tablets and ritonavir (both are Paxlovid) and molnupiravir (Lagevrio). There’s also one antiviral, remdesivir (Veklury), given by IV, says Dr. Linda Yancey, an infectious disease specialist at Memorial Hermann Hospital in Houston. Your health care professional can prescribe the pills, and the IV antiviral may be given if you’re in the hospital, she explains.
The federal government plans to make free COVID tests available again by the end of September 2024. You can order them through the website COVIDtests.gov. You can use the tests through the end of the year, but there will be a limit of four tests per household.
The latest COVID booster shot became available in August of this year. The CDC recommends that everyone age 6 months and older get the new booster.
Respiratory syncytial virus
RSV is more common in children, though adults can get it as well. It resembles a cold, but the severity of RSV symptoms depends on a child’s age, Tranter says. Almost all children have had an RSV infection by age 2, according to the National Foundation for Infectious Diseases.
Here’s a breakdown of the symptoms of RSV, which can vary for different age groups:
— In infants younger than age 1, symptoms often include cough, difficulty breathing, fever and wheezing.
— Younger children may experience wheezing that’s diagnosed as bronchiolitis, which is an inflammation of the small breathing passageways in the lungs called bronchioles. However, this doesn’t mean the child has asthma. “They wheeze because their airways are already small, and the virus causes inflammation inside the airways,” Tranter explains.
— Older children often experience RSV as a cold or pneumonia. If they have asthma, the virus could make it worse.
— Symptoms of RSV in adults can seem like a cold, but they can become severe and are sometimes fatal in those who are older or those who have a weakened immune system or heart disease. Among adults age 65 and over, this type of virus is thought to cause 60,000 to 160,000 hospitalizations and 6,000 to 10,000 deaths annually in the U.S., according to the NFID. That is in addition to its effect on children.
Health professionals will use a physical exam, which includes listening to the lungs, to help diagnose RSV. Other tests usually aren’t done unless a complication from RSV is suspected.
The best care for RSV is liquids, rest and alleviating symptoms with steamy bathrooms and cold-mist humidifiers, Tranter says. Children who develop severe RSV bronchiolitis also may need extra oxygen support and fluids.
An RSV vaccine is available to help protect against the virus. For those on Medicare, the RSV vaccine is covered under Part D (drug coverage).
“Remember that the RSV vaccine protects not just you but also any newborns you might be around,” Yancey says. “If you don’t want to get it for yourself, get it for your grandbabies.”
Cold vs. Flu vs. COVID
It can be confusing to know the difference between a cold versus flu versus COVID as the symptoms are similar. Here are some clues to help distinguish them, according to Yancey.
— A cold is a generic word for an upper respiratory infection.
— A cold actually can be caused by many different viruses, while the flu is caused by influenza viruses.
— Most of the time, a cold will be less serious than the flu.
— Muscle aches are more common with COVID and the flu, though they sometimes occur with a cold as well.
— Compared with the flu, people with colds usually have fevers that are lower but more sore throat and respiratory congestion.
— A runny nose and a sore throat are more common with a cold, but they can sometimes occur with COVID or the flu.
— The flu may start abruptly, while a cold starts gradually.
— Sneezing is common with a cold, less common with the flu and not typically associated with COVID.
Preventing Infections
There are some tried-and-true ways to prevent getting any type of respiratory viral infection:
1. Wash your hands frequently, for at least 20 seconds.
2. Get your recommended vaccines. Everyone should get the flu shot and the COVID booster for this year’s cold and flu season, Yancey advises. Those who are over age 70, pregnant or over age 60 with health conditions like chronic heart or lung disease or should get the RSV vaccine as well.
3. Stay at home when you’re sick, and test for COVID if you think it’s possible you have it.
4. Cover your cough or sneeze with a tissue, and throw the tissue away. If a tissue isn’t available, use your elbow to cover it, not the palm of your hand.
5. Routinely disinfect any surfaces that are touched often.
6. Follow any social distancing guidelines recommended by federal or local authorities.
7. Wear a face mask when you’re sick or around crowds. “Don’t be shy about wearing masks in crowded, indoor places,” Yancey says. “One of the gifts of the pandemic was showing us how highly effective masking is at preventing the spread of respiratory viruses. ”
8. Practice overall healthy habits, such as eating a healthy diet and getting regular exercise. This is important for everyone, but especially for those with chronic health conditions who are even more vulnerable to illness, Dalai says.
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Types of Respiratory Viral Infections originally appeared on usnews.com
Update 09/06/24: This story was previously published at an earlier date and has been updated with new information.