With school back in session and seasons changing, comes an increase in the spread of respiratory infections. Influenza, coronavirus disease of 2019 (COVID-19), respiratory syncytial virus (RSV), and the common cold quickly spread, leading to sick days, missed school and work, increased hospitalizations, and, in severe cases, death. As parents, educators, and healthcare professionals, its essential to understand the causes of these infections, their transmission, symptoms, when to seek treatment, and steps to prevent the spread of these viruses.
Causes
A virus is an organism that is not composed of cells, but rather requires infecting a host, such as a person or animal, to replicate and make copies of itself. Influenza, COVID-19, RSV, and the common cold are all contagious respiratory illnesses, but they are caused by different viruses. COVID-19, RSV, and influenza can cause cold-like symptoms, but they are not the cause of the common cold. Compared to the common cold, these types of infections tend to be more intense and can lead to more severe illness. The most effective way to determine if an illness is viral and which specific type of virus is causing the illness is through diagnostic testing. Typically, testing is done through a nasal or throat swab, depending on the presenting symptoms and patient history.
Influenza:
In the Northern Hemisphere, the flu season is typically between the months of October and May. During this time, the number of influenza cases rises significantly, and the spread can be rampant. There are four types of influenza: influenza A, B, C, and D. The three most common viruses are Influenza A, B, and C. Influenza A and B are more prevalent during flu season and cause seasonal epidemics, whereas Influenza C can be found year-round.
COVID-19:
This infection is caused by a coronavirus, specifically severe acute respiratory syndrome coronavirus 2, SARS-CoV-2. COVID-19 first made its public appearance in 2019 and quickly became a worldwide pandemic by 2020. Since the beginning of the COVID-19 pandemic, reports have shown that as of 2023, there have been more than 712 million cases of COVID-19. At that time, it was estimated that there were more than seven million recorded COVID-19 deaths, but with reporting limitations, the World Health Organization estimates the actual death toll to have been three times as many and closer to 21 million. For many, COVID-19 cases are mild, but for others, deadly.
Respiratory Syncytial Virus:
RSV is an RNA virus that belongs to the Pneumoviridae family. It is the most common cause of bronchiolitis and can cause both upper and lower respiratory tract infections. RSV primarily targets the respiratory system, often accompanied by fever as the body attempts to fight off the virus. RSV causes over 3.6 million hospitalizations annually. Every year, 100,000 deaths occur in children under the age of 5, with half of them occurring in infants under six months of age.
The Common Cold:
A cold impacts the upper respiratory tract and is classified as an upper respiratory infection (URI). There are more than 200 respiratory viruses that can cause the common cold. Rhinoviruses are the most common cause, with over 170 serotypes. In addition to rhinoviruses, other types of viruses that cause the common cold include human coronaviruses, parainfluenza, enteroviruses, adenoviruses, and human metapneumovirus.
Understanding Infection Transmission
Influenza, COVID-19, RSV, and the common cold can all spread through droplet transmission. When an infected individual coughs or sneezes, the infected droplets can spread directly to those in close proximity or to surfaces around them. Viruses can also spread through personal contact with an infected person. For example, if you shake an infected individuals hand and then touch your mouth, nose, or eyes, which serve as portals for the virus to enter the body, you can become infected with the virus.
Viruses can also spread through touching surfaces contaminated by infected saliva, respiratory droplets, or mucus. Infected surfaces can include shopping carts, door handles, phones, utensils, cups, countertops, and any other touchable surfaces. A single infection can spread and ultimately affect many people. For instance, every person with influenza can spread the infection to one or two other individuals. For other viruses, this number can be even greater, emphasizing the importance of understanding how viruses spread and how to stop them.
Flu, Cold, COVID-19, and RSV Symptoms: How to Tell the Difference
Viral respiratory infections can exhibit a range of symptoms, with some overlapping between illnesses and others that are more specific. Some symptoms may be more localized and impact a specific body system, often in this context, the respiratory system, but can also be systemic. Systemic means that the infection has affected the entire body, and the symptoms are indicative of this. Systemic symptoms can include muscle or joint aches, fevers, chills, or fatigue. In some instances, severe infections can lead to sepsis, in which the infection spreads to the bloodstream and can travel throughout the body. Babies and young children, older adults, and individuals with compromised immune systems or particular underlying medical conditions are at higher risk for severe illness.
Influenza
Influenza is a very common viral infection with uncomfortable symptoms that can become life-threatening. Every flu season, between 20 and 40 million people are infected with influenza. With such a large number of influenza cases, it is estimated that influenza accounts for 290,000-650,000 respiratory deaths every year. The duration of influenza symptoms typically lasts for one week, with symptoms beginning 1-4 days after infection.
Symptoms of influenza include:
- Fever
- Muscle and joint pain
- Chills
- Cough (usually dry and can last two weeks or longer)
- Headache
- Sore throat
- Runny nose
- Congestion
- Fatigue
- Malaise
- Diarrhea or vomiting (more prevalent in the pediatric population)
COVID-19
In many cases, symptoms of COVID-19 can last between 1 and 14 days, with symptoms most commonly appearing 5-6 days after exposure. These symptoms can range from mild to severe, with the most common symptoms being fever, chills, and a sore throat.
Other symptoms can include:
- Cough
- Shortness of breath or difficulty breathing
- Congestion
- Runny nose
- New loss of taste or smell
- Fatigue
- Muscle or body aches
- Headache
- Nausea and/or vomiting
- Diarrhea
- Dizziness
- Sore eyes
- Chest tightness or pain
- Hoarse voice
Respiratory Syncytial Virus (RSV)
RSV typically presents with mild cold-like symptoms, but for babies, young children, older adults, and those with underlying medical complications, RSV may be more severe. RSV symptoms typically manifest 4-6 days after exposure and can present in stages as the infection progresses.
Symptoms of RSV include:
- Rhinorrhea (runny nose)
- Congestion
- Coughing (typically appears 1-3 days after onset of symptoms)
- Sneezing
- Fever
- Decreased appetite
- Wheezing
- Irritability
- Increased mucous production (thick respiratory secretions can impair the airway)
- Breathing difficulties
- Decreased activity
- Fatigue
The Common Cold
Common colds typically have milder symptoms compared to the other illnesses discussed. Usually, these infections last less than a week. Symptoms may peak within the first 2-3 days of infection, whereas other respiratory illnesses can last for longer periods of time.
Common cold symptoms include:
- Runny nose
- Nasal congestion
- Fatigue
- Cough
- Sneezing
- Sore throat
- Mild body aches
- Fever (typically a low-grade fever in adults and older children)
- Lymph node swelling
- Fatigue
- Facial pain
Symptom Hints and Tips
So, when looking at the big picture, how can you tell which symptoms are associated with which illness? Here are some of the similarities and differences that may help a healthcare provider determine which infection is present.
- The common cold and influenza can have similar symptoms, but cold symptoms tend to be milder, whereas flu symptoms can be more intense and more severe.
- Shared symptoms between COVID-19, RSV, influenza, and the common cold can include cough, headache, sneezing, runny nose, and congestion.
- A fever is often seen in COVID-19, RSV, and influenza, but rarely in a common cold.
- The common cold and influenza are not as likely to manifest with difficulty breathing. This is more common in RSV and COVID-19, especially amongst vulnerable populations.
- RSV is more targeted at the respiratory system and presents with respiratory symptoms and fever rather than more systemic symptoms such as muscle or body aches.
- A sore throat is more common in COVID-19 and colds than in other illnesses discussed.
When To Seek Treatment
Treatment may vary depending on the specific type of infection and the severity of the illness. Some infections may be mild and require little to no interventions, while others can require lifesaving treatment and therapy. Those who are particularly vulnerable to severe illness include young children and older adults, pregnant women, obese individuals, those with diabetes, and individuals with compromised immune systems due to underlying medical conditions or treatments such as cancer, human immunodeficiency virus infection and acquired immune deficiency syndrome (HIV/AIDS), or organ transplant recipients.
Always assess the ABCs: airway, breathing, and circulation. If any of these are compromised, immediate medical attention must be sought. Grunting, nasal flaring, and retractions of any sort are indicative of severe respiratory complications. Infections can also compromise the airway due to mucous secretions blocking or narrowing the airway. This is especially true of young children with small airways, as well as those who are unable to swallow independently or clear their own airways. Suctioning may be required for those with respiratory secretions that impair breathing. It is also important to notice any signs of lethargy, dehydration, or refusal to consume liquids or adequate nutrition. Always seek medical attention for any questions that may arise or concerns you may have.
Treatment for many of the viral respiratory infections mentioned can include supportive therapy, including rest, supplemental oxygen for those with oxygen saturations < 90%, hydration and nutritional support (potentially intravenous [IV] fluids and nasogastric [NG] feedings), fever and pain management, and the use of over-the-counter medications. Some individuals with severe infections may require intubation, high-flow oxygen, or noninvasive ventilation for breathing assistance. Typically, viral infections require supportive therapy, but in some instances, antivirals may be used to treat such infections. Parents and healthcare providers must always be attentive to the needs of the specific individual and help them receive the care they require, whether the symptoms appear mild or severe.
Be Aware of Red Flags
Influenza, COVID-19, RSV, and the common cold present with a variety of symptoms, and because there can be a risk for severe illness, it is important to be aware of red flags that require immediate medical attention. Red flags can be specifically related to the respiratory system or the body as a whole.
Red Flags:
- Respiratory rate (RR) > 60 in children less than two years old
- RR > 40 in a child > two years old
- Signs of severe respiratory impairment, such as grunting, head bobbing, nasal flaring, retractions, difficulty breathing, or increased respiratory effort
- Signs of circulatory impairments or decreased oxygenation, such as cyanosis, tachycardia or bradycardia (fast or slow heart rate), hypotension (low blood pressure), or weak pulses
- Changes in mental status, including new confusion
- Altered levels of consciousness, including the inability to wake up or stay awake
- Increased irritability
- Decreased urine output
- Lethargy
- Persistent chest pain or pressure
- Fevers that are high, persistent, or don't respond to medication
Individuals, parents, and healthcare providers should also be aware of the dangerous symptoms involving respiratory secretions, drooling, choking, gagging, hoarseness, abnormal breath sounds, increased respiratory effort, and shallow breathing. If there are any questions or concerns, always seek medical assistance.
How to Prevent Flu, COVID-19, RSV, and the Common Cold
Preventative measures are key in decreasing the spread of infections. To better understand how to prevent the spread of infections, it is crucial to reference how they spread: touching infected surfaces, breathing in infected respiratory droplets, or interacting with those who are sick. There are important steps that can be taken to reduce the likelihood of contracting infections.
- Proper hand hygiene: Washing hands with soap and warm water is extremely effective in reducing the spread of viruses. Hand sanitizer can also be an effective method if the hands are not visibly soiled; however, washing hands with soap and water should be the first line of defense if available.
- Limiting respiratory droplet spread: Covering ones mouth when sneezing or coughing and wearing a mask to prevent droplet transmission when appropriate can reduce transmission.
- Avoid sharing contaminated objects: Not sharing utensils, cups, or other items that may house viruses can help reduce the risk of contracting an illness. An infected individual can transfer the virus through contaminated surfaces.
- Distancing: Separating oneself from those who are sick is extremely important to prevent transmission. Avoid scheduling playdates for your children with others who are sick, keep children home from school or daycare if they are showing symptoms of an illness, and avoid engaging in extracurricular activities until the individual is no longer contagious. Schools and daycares may have specific requirements for returning to school, such as an allotted time without a fever or the absence of symptoms to prevent viral transmission in environments that include a lot of close-proximity interactions.
- Vaccines: Currently, there are vaccines for influenza, COVID-19, and RSV. There are no vaccines for the common cold. Vaccines help the immune system recognize the virus that causes the specific infection and learn how to fight against it. For those who are unable to be vaccinated because of age or health restrictions, herd immunity works to prevent the spread of infections. In herd immunity, enough of the general public has been vaccinated that the rate of infection has decreased, blocking the spread of infections to vulnerable populations who are unvaccinated. Vaccines are highly effective at decreasing the severity of symptoms and preventing the spread of viral infections.
Viruses Aren't the Only Thing Making Us Sick
With the increase in viral illnesses that are seen during the autumn and winter months, it is also crucial to acknowledge that illnesses can also be caused by bacteria and have a negative impact on the respiratory system. Bacteria are living, single-celled organisms that can reproduce on their own. Strep throat, pertussis (whooping cough), pneumococcal disease, and tuberculosis are among the illnesses that can spread during the upcoming months and can also lead to severe complications. These illnesses require different treatments using antibiotics that are tailored to the specific type of bacteria. Symptoms vary depending on the location of the infection and whether or not it has become systemic. Always consult with a healthcare professional regarding any infection to receive proper treatment.
Conclusion
With school back in session and respiratory illnesses on the rise, proper infection prevention is crucial to limiting the spread of viruses. Influenza, COVID-19, RSV, and the common cold are all caused by viruses and have a variety of symptoms. Careful attention to symptoms, early treatment, and infection prevention methods such as hand hygiene, distancing, and vaccines can prevent hospitalizations and deaths, and lead to healthier lives this coming respiratory season.
About the Author:
Rachel Pugmire is a registered nurse and freelance writer. She received her Bachelor of Science in Nursing in 2018, with a minor in gerontology. Her areas of expertise include emergency medicine, pediatrics, and pharmaceutical clinical trials. Medical writing has given her a platform to do what she is passionate about, which is educating patients, their families, and other healthcare professionals.
Rachel is an independent contributor to CEUfast's Nursing Blog Program. Please note that the views, thoughts, and opinions expressed in this blog post are solely those of the independent contributor and do not necessarily represent those of CEUfast. This blog post is not medical advice. Always consult with your personal healthcare provider for any health-related questions or concerns.
If you want to learn more about CEUfast's Nursing Blog Program or would like to submit a blog post for consideration, please visit https://ceufast.com/blog/submissions.
