During the first 3 years of life, bronchiolitis is the most common cause of wheezing. Bronchiolitis is caused by the RSV virus. After the age of 3, asthma is the most common cause. Snorting sounds are due to mucus partially blocking the nasal passages. Rattling sounds are due to mucus in the lower throat.
Many asthmatic children wheeze soon after they get coughs and colds.
If this is the case for your child, start the asthma medicine or inhaler at the first sign of any coughing. Always keep the medicine handy, and take it with you on trips. If your supply runs low, get a refill. Try to discover and avoid the substances that trigger attacks in your child. Routinely avoid common triggers such as feather pillows and tobacco smoke.