Signs and symptoms of croup

Signs and symptoms of croup

How soon will signs of a croup infection begin?

Symptoms of viral croup will typically surface within two or three days following exposure to one of the viruses that cause it (with an incubation period of 24 to 72 hours). This is also the time when a child is at their most contagious and at high risk of infecting others.

Infection can spread to anyone, of any age and will generally present signs of sore throat, cough and a fever. Older children (including teenagers) and adults may not develop the characteristic stridor and barking cough, however, but instead get laryngitis (inflammation of the voice box that causes a loss of voice).

A pregnant woman who is exposed to parainfluenza viruses can also fall ill with similar, but severe symptoms of croup (more severe than a woman who is not pregnant at the time of infection), but infections have not been known to cause any serious harm to a developing foetus.

How long does viral croup last?

Viral croup symptoms will typically last between 3 and 7 days (sometimes up to 10 days in severe cases). A cough may linger for a few weeks, but once a child’s fever has broken and their body temperature has returned to normal, they are usually no longer contagious and may even begin to feel a lot better. Only at this stage can school-going children return to the company of others, without risk of spreading infection.

The first 2 or 3 days of croup symptoms (when a child is most contagious) are usually the worst of the infection. Thereafter, symptoms begin to subside and become less severe.

What are the most common signs and symptoms of croup?

Young children under the age of 3 generally tend to experience severe symptoms of croup. A young child’s respiratory system is normally smaller (i.e. they have smaller airways) and still developing during early years of life.

A young child will typically become highly agitated when suffering from croup. Increased fussiness and crying often aggravate symptoms even further, worsening discomfort and increasing breathing difficulties.

The most common signs and symptoms for croup include:

  • Nasal congestion (a blocked nose)
  • Runny nose
  • Sore throat
  • Fever (37°C / 100°F to 39°C / 103°F)
  • Heavy breathing (laboured and noisy / stridor as air is inhaled and exhaled through the airways)
  • Hoarse / raspy voice
  • Barking cough (often worse at night and often aggravated by agitation, crying and anxiety)
  • Swollen lymph nodes / larynx and trachea
  • Redness of the eyes
  • Retractions (characterised by skin which pulls between the ribs when breathing and or/ collarbone, especially if breathing at a fast pace)

Spasmodic croup signs and symptoms typically come on suddenly (‘out-of-the-blue’). A child may appear to be well, often when put to bed and then suddenly awaken with signs of croup – a barking cough, stridor, fever and sore throat. Unlike viral croup, symptoms of spasmodic croup can resolve within 8 to 10 hours, but can recur with the same acute onset pattern by nightfall (sometimes on up to 3 or 4 consecutive nights). A ‘wet’ cough and mucus-like nasal discharge is often seen in persisting symptoms.

Why is croup worse at night?

A bout of croup almost always appears to be at its worst during the night. It is during these hours that coughing spasms worsen, and a child shows more signs of distress. During sleep, or when at rest (i.e. lying down), a change in blood flow takes place, contributing to altered breathing capacity in the respiratory tract. Coughing and breathing difficulties can also worsen as a result of dry air. If breathing difficulties are not too severe, and a parent or caretaker can control the agitation of the child, symptoms can be reasonably managed with home treatment.

When to call the doctor if your child has croup

Symptoms relating to either type of croup, which are life-threatening are rare, and the majority of instances will be mild. Severity of symptoms depends largely on the amount of narrowing which occurs in the respiratory airways. The more narrowing, the more effort is needed to inhale sufficiently, which can impact a child’s ability to breathe.

A child with severe symptoms will likely refuse to lie down, cry and even demand to be kept in an upright position. Retractions of the skin may be noticeable just above the collarbone and between the ribs.

Normally, once a child’s ability to breathe is severely affected, and he or she appears exhausted (i.e. difficult to waken and when awake is highly agitated and listless), it is a strong sign that medical intervention is required and croup has reached a severe stage.

Breathing difficulties can escalate quickly, so any parent or caretaker who becomes concerned at any point should rather take precaution and seek assistance from a medical professional as soon as possible.

If a child begins to experience the following, along with breathing difficulties, a medical doctor should be consulted as soon as possible:

  • Stridor, which has worsened and become more high-pitched
  • Rapid or fast paced breathing (approximately 60 breaths taken in a minute)
  • Difficulties with swallowing (often accompanied by drooling)
  • Signs of dehydration (with dry lips and tongue, few tears when crying, sunken eyes and very little to no urine output)
  • Cyanosis (grey or blue discolouration of the skin – usually apparent around the nose, mouth and fingernails)

Severe exhaustion and reduced respiratory ability must be treated as a medical emergency so as to avoid complications of respiratory failure.

In any event where symptoms of croup do not appear to resolve within a week (especially if a child is still feverish with a temperature around 37.5°C to 39°C / 99.5°F to 103°F) or recur (with or without a fever), a doctor must be consulted as soon as possible. This is necessary so as to rule out any possibility of other conditions causing symptoms, or perhaps a bacterial infection.

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