Overview

Children's health and wellbeing is one of the worries that parents face on a daily basis. From common colds to more severe illnesses, parents always worry about their children and want what is best for them. In this article, we will discuss two illnesses that can affect our young ones: croup and measles. Croup is an illness that occurs in childhood and affects the trachea (windpipe), bronchi (airway to the lungs), and the larynx (voice box).¹ It is commonly caused by viruses, most notably parainfluenza virus although other viruses are capable of this illness too.¹ Measles, on the other hand, is caused by the measles virus (MeV) which is a highly infectious virus leading to a systemic rash and causes more than 100,000 deaths in children per year.² To further delve into the differences between the two, more information will be provided below, so let’s get into it.

Croup

As mentioned above, croup occurs due to viral infections, with 70% of the cases being due to parainfluenza virus, while the rest include influenza A and B, respiratory syncytial virus, adenovirus, measles and human coronavirus NL63.³ It is an acute infection that affects the upper respiratory system, causing inflammation in the mucosa.⁴ Croup syndrome is an urgent paediatric condition that is characterised by an abrupt development of a barking cough (mostly at night), accompanied with inspiratory stridor, hoarseness, and distress due to upper-airway obstruction.⁵ The pathogenesis of croup is defined as generalised inflammation of the dilated pits, swelling of the mucosa, and hypersecretion of the mucous glands.⁵ Additionally, there is a narrowing of the subglottic area which can lead to respiratory tract obstruction.⁵  

There are 3 scores for croup:⁵

• Mild croup: This is defined as a croup of a score 0 to 2, with occasional barking cough, absence of stridor during rest, and absence of mild retractions of the skin of the chest wall
• Moderate croup: This has a croup score of 3 to 5 and is associated with frequent barking cough, audible stridor during rest and retraction of the skin of the chest wall (also known as suprasternal and sternal wall retraction) at rest with mild agitation
• Severe croup: This stage of croup is of score from 6 to 11. It is characterised as a frequent barking cough, prominent inspiratory and sometimes expiratory stridor, significant sternal wall retractions, decreased entry of air upon auscultation, and marked distress or agitation

Symptoms and complications

The symptoms of croup usually occur in late autumn or early winter, however, they can happen during any time of the year.¹ The symptoms include:¹ 

• Barking cough
• A hoarse or croaky voice
• Breathing difficulties
• Stridor which is a harsh grating sound that can be heard when inhaling

Stridor is more commonly detectable when the children cry or cough, but in more severe cases it can be detected when they are resting or sleeping.¹ Some children will present cold-like symptoms such as a sore throat, runny nose, and fever, and the symptoms tend to get worse at night.¹ It is rare for children to die of croup and for complications to occur, however, obstruction to the airway can lead to respiratory distress and even respiratory arrest, which is when the heart continues to beat but the breathing stops.¹ Other complications include secondary infections, such as pneumonia or bacterial tracheitis, which can develop after the initial viral infection that causes croup. Also, middle ear infection and lymphadenitis can develop.¹

Diagnosis and treatment

Diagnosis of croup is done by a visit to the GP, where their physical symptoms are checked such as the sound of their cough and the presence of fever. Sometimes pulse oximetry would be done to test the child’s level of oxygen, and to rule out other possible causes of the symptoms such as allergies, epiglottitis, or congenital lesions.¹ It is important not to try and check your child’s throat by yourself as this can trigger a spasm response of the airway, which will cause it to swell and make breathing even more difficult.¹

Treatment of croup is dependent on the symptoms and how severe they are, for example:¹

• Painkillers to relieve pain such as paracetamol
• Rest
• Intake of plenty of fluids
• Corticosteroid medications such as dexamethasone or prednisolone to help decrease the swelling in the throat 

In cases of severe croup, immediate treatment with nebulised adrenaline is done and hospitalisation is required.^1,5

Prevention

Croup is similar to the common cold in many ways and its prevention is difficult. However, there are some steps we can take to reduce the risk such as maintaining good hygiene to reduce the spread of infection like. regular washing of the hands and cleaning surfaces.¹ Additionally, vaccinations can help protect against some of the infections that cause croup such as:¹

• MMR: Protects against measles, mumps and rubella
• DTaP/IPV/Hib: Protects against diphtheria, tetanus, polio, Haemophilus influenza B, and whooping cough

Measles

Measles is a febrile rash disease that can cause serious complications and even death in children. It is one of the world’s most contagious viral illnesses.⁶ Prior to vaccinations, measles caused significant illness and death worldwide, it caused approximately 135 million cases and more than 6 million deaths globally each year.⁶ It spreads through tiny droplets from the nose or mouth of infected individuals when they sneeze or cough, which can be inhaled or touched by others. The virus can survive on surfaces for several hours.⁷ 

The measles virus is a morbillivirus of the paramyxovirus family.⁸ It is a negative sense, single-stranded RNA virus and is considered monotypic, meaning it belongs to a genus with only a single species.⁶ After infection, the virus undergoes an incubation period during which it will replicate in the alveolar macrophages and dendritic cells before causing a systemic infection, where the infected lymphocytes will spread the virus through the body to the major organs and peripheral tissues, such as the skin and lungs.⁶ In uncomplicated cases of measles, symptoms usually subside a few days after developing the rash and patients who recover develop a strong and competent immunity that lasts a lifetime.⁶

Symptoms and complications

Measles is common in young children and has multiple symptoms, including:⁷

• Flu-like symptoms: runny nose, coughing, sneezing
• Red and sore eyes that might be sensitive to the light
• Swollen and watery eyes
• Fever
• Tiny grey or white spots in the mouth
• Body ache
• Lack of appetite
• Fatigue or lethargy
• Irritability

A measles rash is seen 2 to 4 days after the initial signs of infection and it typically fades after a week.⁷ The rash appears as small red or brown, flat or slightly raised spots that can join together into large blotchy patches.⁷ This rash first appears on the head or neck and then spreads to the rest of the body.⁷

Measles can pose a serious health risk if it spreads to different parts of the body, such as the brain or lungs, leading to complications such as:⁹

• Seizure
• Blindness
• Pneumonia
• Meningitis

While these complications are rare, they can still occur. Babies and immunocompromised individuals are at a higher risk than others.⁹ Additionally, measles can have an effect on pregnancy, it can cause low birth weight, premature birth, miscarriage, and stillbirth.⁹

Diagnosis and treatment

Diagnosis of measles can be done through the examination of the symptoms as well as laboratory tests to confirm the results.¹⁰ The laboratory tests involve testing for the measles-specific IgM antibody in the serum as well as the RNA of the virus using RT-PCR from a respiratory sample. This is done by obtaining a serum sample and a throat or nasopharyngeal swab.¹⁰ Urine samples, which may also contain the virus, can be used for testing as well.¹⁰

Prevention

There are several steps that we can take to reduce and prevent the transmission of measles including:⁷

• Take time off school or work for at least four days when the rash appears
• Regular hand washing and maintaining good hygiene
• Disposing of tissues as soon as they’ve been used
• Avoiding close contact with people who are not fully vaccinated
• Getting the MMR vaccine
• In case the MMR vaccine is not suitable, patients can opt for human normal immunoglobulin (HNIG) treatment if they are at immediate risk of contracting measles

Summary

Croup and measles share some similarities but they also have distinct differences. Both can affect children and require attention. In most cases, croup can resolve on its own and does not pose a high risk, unlike measles which can be quite deadly if left untreated. Croup can also develop as a result of a measles infection, making it important to diagnose the cause of the illness properly to ensure your children receive the appropriate care and treatment.