Pediatrics is very seasonal regarding infectious diseases and their consequences. Some of the most common infections seen during the wintertime are respiratory syncytial virus (RSV), influenza virus, and rotavirus. Exacerbations of asthma are also more commonly seen during the winter, as there are many children whose main trigger for wheezing is the presence of an upper respiratory infection caused by one of the common winter viruses.

RSV affects people of all ages, but most commonly infects babies and young children. By age two years, a large majority of children have been infected. There are more than 120,000 hospitalizations per year in the United States for RSV related disease. RSV is one of the most common causes of both upper and lower respiratory tract infections in the pediatric population.

The most serious RSV infections occur in infants and young children and especially those who are born prematurely, have underlying lung or heart disease, or those with immune problems. RSV is transmitted through direct contact with respiratory secretions or indirectly from contaminated surfaces. Presence in day care centers, living in crowded conditions, or being exposed to cigarette smoke are risk factors for contracting infection.

The season for this viral illness usually clusters between November and April in the northern hemisphere. The symptoms may be as mild as slight upper airway congestion and runny nose and cough to more severe infection with lower airway involvement exhibited by wheezing, severe cough, and increased work of breathing. RSV infection in the first 6 months of life is often associated with recurrent subsequent wheezing episodes. It is thought that there is some association between significant infection with RSV and predisposition to asthma or reactive airway disease.

RSV may be rapidly detected by obtaining a nasal specimen from the patient. Treatment usually involves supportive and symptomatic care. Supplemental oxygen and upper airway suctioning are the hallmarks of treatment for babies with RSV bronchiolitis (lower airway tract disease). The use of breathing treatments with bronchodilator aerosols (the medicine usually used to treat asthma) are usually of little value in treating these babies. There is currently no vaccine available, but there is an antibody preparation for those babies at increased risk. This may be used as a preventative measure if the appropriate criteria are fulfilled.

Influenza virus infections tend to cluster during the winter months as well. There are usually strains of both Influenza A and B which are prevalent during any one season. The symptoms range from mild upper respiratory symptoms with low grade fever to much more severe cases with high fevers, shaking chills, severe cough, muscle aches, and lung involvement. Associated signs and symptoms include headaches, sore throat, and conjunctivitis. Some strains also cause vomiting, diarrhea, and abdominal pain.

Secondary complications of influenza include pneumonia, myositis (muscle inflammation), and meningitis/encephalitis. Fortunately, most children who contract influenza virus have a relatively mild illness with few complications.

Treatment involves symptomatic care including pain and fever control and prevention of dehydration. There is medication available which may be used in select patients under certain circumstances. This may shorten the course of the illness, but is not a cure.

Influenza vaccine is available and targets the expected infectious strains each year. While not always correctly predicted, the immunization will still afford some protection to whichever strain actually prevails. Injectable influenza vaccines are indicated for anyone over the age of six months who is not allergic to eggs. The oral vaccination available is a live virus vaccine and is only indicated for patients who meet the age and condition criteria.

Rotavirus causes gastrointestinal illness and affects nearly all children in the United States by the time they are three years old. It occurs primarily in the late fall and winter in Southern California. It is spread by “fecal-oral” transmission, meaning that the virus is spread by dirty hands onto foods or surfaces. Rotavirus can live for a prolonged period of time on surfaces like plastic and metal and on objects such as toilet handles and sinks. There is some evidence that it is also spread by coughing and sneezing, as well.

Symptoms of rotavirus usually begin two to four days after exposure. Vomiting occurs in about 75% of children and usually lasts a few days, as does a fever. Diarrhea is usually very watery and generally lasts five to six days, but can continue for much longer in some individuals, and may result in dehydration. Abdominal pain and cramping can be severe.

Treatment for rotavirus involves trying to keep children comfortable and hydrated. Hydration by mouth is the most effective way to prevent dehydration. For children who are able, a regular diet should be continued. Oral rehydration solutions, such as Pedialyte or Ricelyte, should be given to children who are vomiting or who are mildly dehydrated. Severely dehydrated children may need intravenous fluids. Regular diet should be restarted as soon as possible, with an emphasis on rice, banana, and yogurt with lactobacillus added. Over the counter medications which are marketed to stop vomiting and diarrhea should not be used.

Hand washing with soap and warm water is the most effective way to prevent the spread of rotavirus. Transmission of mother’s antibodies through breast milk is helpful in providing immunity. There is now a live oral vaccine series which may be given to infants with their routine immunizations.

Asthma is the most common chronic childhood illness in the United States and is responsible for over 10 million lost school days each year. It is a result of airway inflammation and hyper-responsiveness to various triggers. Symptoms of asthma vary widely and can range from audible wheezes to intermittent or persistent cough, exercise intolerance, shortness of breath with minimal exertion, and waking up with shortness of breath or cough. The incidence of asthma has almost doubled between 1980 and 1996, and African Americans are affected twice as often as Caucasians and have a higher associated death rate.

There are many things which affect the incidence and persistence of asthma. Maternal smoking is the greatest risk factor for wheezing in infants. Children with allergies or a family history of asthma are at greater risk for developing asthma. House dust mites, cockroaches, mold, and indoor pets are important triggers. Exposure to viruses may cause significant wheezing during the first three years of life, but children without other risk factors (such as allergies and family history) generally outgrow this reaction. It is for this reason that the frequency of asthma attack in young children is higher during the winter months when there are more upper respiratory infections.

Treatment of asthma involves education about symptoms, triggers, and when to use specific medications. All children should have a written “Asthma Action Plan” to follow during periods of both wellness and asthma symptoms. Short acting inhaled or nebulized medications, such as albuterol, are used for intermittent symptoms to relax the airways and make breathing easier. Inhaled steroids are important in helping prevent asthma symptoms. Other medications may be used for more severe or persistent asthma. In some cases, children with significant allergies may be desensitized with “allergy shots”.

Top of Page