In the preliminary stages, symptoms of bronchiolitis are similar to those of common cold. As the disease progresses to more advanced stages, signs and symptoms take a severe turn, and include:

• Development of cyanosis, characterized by bluish coloration of skin, which occurs due to lack of oxygen supply
• Cough that eventually gets worse
• Wheezing accompanied by dyspnea
• Fatigue
• Fever
• Tachypnea
• Development of intercostal retractions, a condition, wherein the muscles surrounding the ribs sinks in, when the affected child tries to breathe
• The nostrils of the affected child widen when he tries to inhale [8]

A preliminary physical examination will be conducted, to study the signs and symptoms of the disease, and to also listen to the wheezing sounds, with the help of a stethoscope. No other tests would be required, other than physical examination. However, in case the child has developed severe bronchiolitis, then the following tests would be employed to check for sings of pneumonia [9].

• Chest x-ray: This would be done, to check for signs of pneumonia.
• Blood tests: Are necessary to determine the levels of leukocytes. Leukocytosis is a sign of infection. Blood tests would also help analyze the levels of oxygen in the body.
• Mucus sample test: A swab of the mucus sample will be tested, for the presence of virus [10].

Bronchiolitis can be successfully treated at home, with supportive care. The following methods are adopted, for treating children affected with lung infections [11]:

• Drinking plenty of fluids is necessary. Mothers are advised to continue with breast milk, and, or formula milk, for infants.
• Plenty of rest is advised.
• Use of humidifier is indicated, which would help in loosening the thickened accumulated mucus.
• In many cases, nebulized albuterol treatment is also administered. Inhaled hypertonic saline is also an effective treatment regime [12].

The prognosis of the condition is favorable, if treatment is initiated in the preliminary stages. Failure to do so may cause breathing problems in the child, and require hospital admissions. Symptoms begin to improve within 3 days, and children should completely recover by 1 week. In rare cases, children develop pneumonia, and other associated respiratory infections. However, affected children are at an increased risk of developing wheezing problems in the future, and can even develop asthma later in their lives [6] [7].

Respiratory syncytial virus (RSV) causes bronchiolitis in majority of the cases. It is a contagious disease, and can spread through infected droplets, that are spread in air by individuals contracted with this disease condition. In addition to RSV, other viruses such as influenza virus, adenovirus and parainfluenza virus can also cause bronchiolitis.

The condition is common during the winter season, and early months of spring. Children less than 2 years and those with a compromised immune system fall easy prey to the virus [2].

It has been estimated that in the US, about 25% of respiratory tract infections occur in the first year of life. It has also been reported that about 132,000 to 172,000 RSV-related hospitalizations occur in the pediatric population. The estimated cost from hospitalization is calculated to be approximately more than $700 million annually [3].

Anatomically, bronchioles are the small airways, measuring less than 2mm in diameter. These airways get inflamed due to viral agents, which in turn causes mucus buildup, making passage of air difficult. Such sequence of events causes difficulty in passage of air, into and out of the lungs, making breathing difficult for the affected individuals [4]. Bronchiolitis is a contagious disease. It is spread when healthy individuals come in contact with respiratory droplets of infected individuals, when they sneeze, cough or talk [5].

Majority of the cases of bronchiolitis can seldom be prevented; owing to the fact, that the virus is commonly found in the environment. However, individuals are still advised to adopt certain measures, such as frequent hand washing, which can, to a certain extent, prevent the spread of the disease.

Boosting a child’s immunity is yet another way, which can help prevent development of bronchiolitis. A drug known as palivizumab, has promising effects in boosting the immune system.

Such a type of lung infection is a common occurrence amongst children less than 2 years of age. In many cases, bronchiolitis mimics the signs of common cold and cough in the preliminary stages. As the disease advances, affected individuals would also experience wheezing, coughing and difficulty in breathing. Supportive care forms the basis of the treatment regime, and children do well with medications and nebulized epinephrine [1].

• Definition: Bornchiolitis is inflammation of the bronchioles of the lungs, due to viral infections. This causes accumulation of mucus in the bronchioles, which ultimately leads to breathing difficulties in the affected children. The condition is common during the winter season, and children less than 2 years of age, commonly fall prey to it.
• Cause: The respiratory syncytial virus is the major cause of bronchiolitis. Other viruses such as influenza virus, parainfluenza virus and adenovirus can also cause this disease condition. Bronchiolitis is an infectious disease, and can spread by coming in contact with respiratory droplets of infected individuals.
• Symptoms: Symptoms of bronchiolitis include cough, wheezing, cyanosis, fatigue, fever and rapid breathing. Affected children experience intercostals contractions, which is characterized by contractions of the ribs muscles, when the child breathes.
• Diagnosis: In majority of the cases, preliminary physical examination is enough, to diagnose the condition. However, if the child is suffering from severe form of bronchiolitis, then more tests would be required, to diagnose onset of pneumonia.
• Treatment: Many children can be treated at home, through supportive care. Medications are of little help in treating viral infections. In addition, use of bronchodilators in such cases, is also contraindicated. Affected children are advised plenty of rest, along with fluids, and mothers are asked to continue breast feeding their babies. Use of nebulized albuterol is also indicated.

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