Respiratory Syncytial Virus

Respiratory syncytial virus, or RSV, is a very common virus that infects the respiratory tract. In many older children and healthy adults it causes cold-like illness, but in infants, older adults, and medically vulnerable people it can lead to more serious lower respiratory tract disease such as bronchiolitis or pneumonia. ^[1][2]

RSV is especially important because it is one of the leading causes of respiratory illness in young children. At the same time, it is not only a pediatric problem. Adults with chronic heart or lung disease, weakened immunity, or advanced age can also become seriously ill. ^[1][2][3]

What are the symptoms?

RSV often starts with runny nose, congestion, cough, sneezing, reduced appetite, and mild fever. In very young babies, irritability, reduced feeding, and breathing difficulty may be more noticeable than classic cold symptoms. ^[1][2]

In some patients, especially infants, the infection progresses to wheezing, fast breathing, chest retractions, nasal flaring, and bronchiolitis. Older adults and people with chronic disease may develop worsening cough, shortness of breath, or pneumonia. ^[1][2][3]

How does it spread?

RSV spreads through respiratory droplets, direct contact, and contaminated surfaces. The virus can move easily through households, childcare settings, and crowded indoor spaces. ^[1][3]

Hand washing, avoiding close contact when someone is ill, cleaning frequently touched surfaces, and protecting vulnerable infants from sick contacts can help reduce spread. ^[1][3]

Who is at higher risk?

The highest-risk groups include infants—especially premature babies—older adults, people with chronic heart or lung disease, and immunocompromised patients. Severe RSV can also be more likely in infants younger than 6 months and in children with certain underlying medical conditions. ^[1][2][3]

How is it diagnosed?

Diagnosis is often based on symptoms and examination, especially during seasonal circulation. In selected cases, viral testing may be done, particularly in high-risk or hospitalized patients. The clinician also evaluates breathing effort, oxygenation, and hydration status. ^[1][2]

How is RSV treated?

Most RSV infections are managed with supportive care: fluids, rest, fever control when needed, and monitoring of breathing. Antibiotics do not treat RSV because it is a virus. In babies and high-risk patients, supportive care may include suctioning, oxygen, or hospital-based treatment if breathing becomes difficult or feeding becomes inadequate. ^[1][2]

When should you seek medical care?

A baby who is breathing fast, drawing in the chest, flaring the nostrils, feeding poorly, appearing unusually sleepy, or showing bluish color around the lips needs prompt medical assessment. In adults, shortness of breath, worsening cough, confusion, or signs of dehydration also justify evaluation. ^[1][2]