Introduction

Are you a parent of children under 3? Do you always dread the arrival of the incoming winter?  You are not alone! Many parents with small children get exhausted because their kids fall sick frequently during winter. Not to forget how worse the winter viral diseases can be on the tender airways of these tiny humans. 

You may wonder how to distinguish one viral infection effectively from another as they have overlapping symptoms.

In this article, you will get sufficient information to differentiate croup and RSV, the top 2 viruses that badly impact the health of kids under 3.

Brief overview of croup and RSV

Although both viruses and bacteria can cause croup, viral croup is the most common. Parainfluenza viruses type 1 and 2 are the primary causative agents of croup. However, other viruses such as measles, influenza A and B, and adenovirus can also be responsible for causing croup.¹ 

On the other hand, an RSV infection is caused by the respiratory syncytial virus (RSV) which spreads through infected water droplets in the air while somebody with an RSV infection coughs or sneezes near your child.² In addition to causing an illness defined by its characteristic symptoms, an RSV can also be responsible for causing viral croup.¹ 

You need to be aware of the fact that both croup and RSV are known to cause serious respiratory illnesses to your children targeting your children’s lungs and respiratory tracts (airways). It often peaks during the winter months.³ 

Small children, especially those in the age range from 6 months to 3 years, have airways that are smaller in width and shorter in length. They get swollen easily when infected by a virus and the swelling narrows their airways further down. This eventually makes it difficult for your kid to breathe.^4,5 

As croup and RSV have many common factors, it is important to understand the differences. It makes you aware of the infection-specific and serious symptoms. This also provides ways for precise diagnosis and customised treatment.

Which age groups are susceptible?

Croup can affect infants as young as 6 months to 3 years, but risks are high among toddlers between 1-3 years of age. Although mild symptoms are prominent among affected children, croup can get worse and life-threatening.⁶ It rarely affects adults.

RSV affects everyone regardless of age. However, the impact is higher among small children under 2 years, especially premature babies. Also, older children and adults (over 60 years) with heart or lung problems and weakened immune systems are susceptible to RSV infection.⁷ 

Healthy adults will have symptoms such as sneezing, mild coughing and runny nose similar to the common cold.⁷

Which organs are affected?

Croup mainly affects the upper respiratory tract of your children, including the larynx (voice box) trachea (windpipes) and bronchi (large tubes that connect the trachea to the right and left lungs). Therefore, croup is also known as laryngotracheobronchitis.⁸ Furthermore, the infection makes the upper respiratory tract swollen leading to breathing difficulties.

RSV is known to affect the areas in the lower respiratory tract. The virus targets your child’s bronchioles (smallest airways in the lungs) and lungs in particular. The infection that affects bronchioles is called bronchiolitis. During this condition, the bronchioles get inflamed along with mucus build up resulting in breathing difficulties. 

Sometimes, the virus affects the lungs and causes pneumonia (inflammation of the lungs) which worsens the condition and can be very serious in infants and toddlers.⁹

What are the signs and symptoms?

Croup

One of the characteristic features of croup is the distinctive rough cough when forced through narrow airways. It sounds like a seal's bark which worsens at night. In addition, your child may have a high-pitched stridor due to the obstructed airways and the irregular airflow which may result in respiratory distress.^10,11 Croup can be mild, moderate or severe and the symptoms differ in children.

Mild croup

A mild croup lasts only a week or less. Your child may present symptoms like a common cold with a runny nose briefly and then a harsh, barking cough may start within 48 hours.⁶ Other notable symptoms are:

• Fever
• Rash
• Redness in the eye
• Scratchy or husky voice 
• Swollen lymph nodes

Moderate or severe croup

The moderate to severe symptoms of croup include:

• Difficulty in breathing and distress
• Restlessness - child often crying or upset
• Anxiety or nervousness
• Visible retractions of skin around the child’s ribs and above the breastbone
• Bluish appearance of skin due to reduced level of oxygen especially around nose, mouth and fingernails (cyanosis)
• Excessive drooling and difficulty in swallowing¹²

RSV

When your child has an RSV infection, it takes approximately 5 days for the first symptom to appear after the first exposure to the virus.¹³

Mild RSV infection

The first signs are mild, similar to a common cold and your child may recover in a week or two. However, sometimes, it may progress to severe and life-threatening. 

• Stuffy nose 
• Coughing
• Sneezing
• Consistent low-grade fever 
• Headache
• Sore throat

Severe RSV infection

Infants are severely affected by RSV in general and  the symptoms include:

• High fever
• Dry and rough cough
• Wheezing (noisy breathing out) 
• Rapid and shallow breathing 
• Distress in breathing
• Bluish colour of the skin (cyanosis)
• Poor feeding
• Unusual tiredness 
• Extreme fuzziness

What are the complications?

Croup

Although complications are rare, sometimes your child may need immediate medical attention and a hospital stay if they need:

• Supplemental oxygen to keep up safe levels
• Intravenous fluids due to dehydration
• Breathing treatments to relieve repeated wheezing episodes

RSV

Your child may get affected by RSV multiple times within the same season of infection.¹⁴  The risks of reinfection are higher in children who go to daycare facilities or in infants having an older sibling attending daycare. In addition, older adults who are immunocompromised or with heart /lung issues may develop complications often. 

The major complications of RSV infections are:

• Requiring hospitalisation to monitor oxygen levels
• If your kid gets pneumonia or bronchiolitis and has severe respiratory distress. 
• May develop asthma later in life
• Frequent middle ear infection 

What are the currently available treatment options?

The treatment options for croup and an RSV infection are almost similar and always depend on the severity of your child’s condition. 

Mild cases

Generally, home remedies would suffice to treat mild cases and comfort your child as listed below:

• A cool mist from a humidifier or cool air from an open window helps your child by soothing the dry and irritated airway. 
• You can also keep the hot water shower running to generate steam and sit with your child inside the bathroom.
• The child's throat will clear up with the Intake of warm fluids which may help to prevent dehydration. 
• Use nasal saline drops and suction to clear their stuffy nose.
• Sometimes, the doctor may recommend over-the-counter medication such as paracetamol or ibuprofen to reduce your child’s fever and discomfort due to body pain.
• Avoid smoking indoors as being around smoke can worsen your child’s condition.
• Make them sleep in an elevated position to ease breathing.
• Your child’s doctor may prescribe antibiotics if a secondary bacterial infection is suspected.

Moderate to severe cases

You must visit the emergency room (ER) if your child’s condition gets severe.

The treatment options for moderate to severe croup include:

• Prevent dehydration through intravenous (IV) fluids.
• Monitor oxygen levels, breathing and heart rate regularly. 
• Very rarely, there is a need for a breathing machine (mechanical ventilation).

For children with severe croup,  the following treatment strategies give immediate and effective relief:

• Your child will be given corticosteroids¹⁵ in the ER and within the first six hours, it reduces the swelling of the larynx.
• Your child will be given nebulised epinephrine (as inhalation mist)¹⁵ and within minutes, it reduces the swelling in your child’s airways.

However, the above is not found to help treat RSV infection.¹⁶

What are the preventive measures?

The following simple measures can play an effective role in preventing both croup and RSV infection:

• Wash your hands often and practise it with your child regularly
• Avoid meeting other kids with fevers and cold
• Never share drinking glasses with your children
• Cover your mouth and nose when coughing or sneezing and encourage your child also to do the same
• Dispose of used tissues immediately
• Consider washing your child’s toys regularly

Summary

Both croup and RSV infect small children under 3 years of age. They affect the respiratory tract of children and can cause a range of symptoms right from mild common cold-like symptoms to serious respiratory distress depending on the severity of the infection. 

A clear understanding of the differences between croup and RSV is essential for you as parents to know what exactly your child is dealing with, what sort of home remedies might ease them and when they need acute medical attention. It also helps to address the infection promptly and prevents complications.