What causes prolonged fever in children? How long should a fever last? When should you take your child to the emergency department? Get answers to these questions and more.

Understanding Fever in Children

Fever is one of the most common reasons parents call the pediatrician, especially during the winter months when various viruses are circulating. According to Dr. Karen Acker, a pediatric infectious diseases specialist, a fever, defined as a body temperature of more than 100.4°F, is the body’s normal response to fighting an illness. It means the immune system is doing its job, and in most circumstances, there is no need to be worried.

Duration of Fever

Typically, a fever due to a common virus can last from 24 hours to three to four days. However, fevers can sometimes last longer, even over a week, and this is not necessarily a reason to be alarmed, as long as the child is not struggling with other symptoms, such as dehydration, shortness of breath, or severe lethargy or irritability. If the fever persists for seven days or more, it is a good idea to bring the child to the pediatrician for evaluation.

Causes of Prolonged Fever

Viruses such as the common cold, RSV, the flu, and COVID-19 can often look alike, and the only way to know for sure is to have the child tested by the pediatrician. Influenza is typically accompanied by high fever, body aches, fatigue, and upper respiratory symptoms, including cough. RSV usually causes runny nose and cough, but children can get a fever, and 20% to 30% of children have faster breathing due to infection of the lower airways (known as bronchiolitis). COVID-19 can cause runny nose, cough, and fever, but it appears to be a less common cause of more severe disease and hospitalization in children compared to RSV and influenza.

When to Seek Medical Care

For infants less than 6 weeks old, a fever always warrants a visit to the emergency department, as young babies are at higher risk for infection. For older infants, you should discuss with your pediatrician, who will recommend whether to go to the emergency room. If your child is unable to drink, is dehydrated (has less than five wet diapers in 24 hours), has difficulty breathing, or is inconsolable, it is recommended to go to the emergency department.

Treating Fever at Home

Treating a fever is more about treating the symptoms rather than trying to bring down the temperature. If a child has a fever and is still playing, drinking fluid, eating, and running around, there is no need to treat it with medication. However, if the child is feeling uncomfortable, over-the-counter fever reducers, such as acetaminophen (Tylenol) and ibuprofen (Advil, Motrin), can reduce the temperature and help them feel better. Remember, babies under 6 months cannot take ibuprofen – only acetaminophen.

Febrile Seizures

Febrile seizures are a common occurrence in young children, and they are caused by the fever triggering seizure activity in the brain. While they can be frightening for parents, they are generally not harmful and do not indicate a more serious underlying condition. If a child experiences a febrile seizure, it is important to remain calm, ensure the child is safe, and seek medical attention.

When to Worry About a Fever

Fever is a normal part of the body’s immune response, and in most cases, it is not a cause for concern. However, if a child is unable to drink, is dehydrated, has difficulty breathing, or is inconsolable, it is important to seek medical attention immediately. Additionally, if a fever persists for more than seven days, it is a good idea to have the child evaluated by a pediatrician.

Differentiating Viral Illnesses

While the common cold, RSV, the flu, and COVID-19 can all cause fever, there are some general differences in the symptoms. Influenza is typically accompanied by high fever, body aches, fatigue, and upper respiratory symptoms, while RSV usually causes runny nose and cough, and COVID-19 appears to be a less common cause of severe disease in children compared to RSV and influenza.

Treating Fever at Home

If a child has a fever but is otherwise acting normally, there is no need to treat the fever with medication. However, if the child is feeling uncomfortable, over-the-counter fever reducers can help alleviate the symptoms. It is important to remember that babies under 6 months can only take acetaminophen, not ibuprofen.

Seeking Medical Attention

For infants less than 6 weeks old, a fever always warrants a trip to the emergency department, as young babies are at higher risk for infection. For older infants, it is best to discuss the situation with the pediatrician, who can provide guidance on whether the child needs to be seen in the emergency room.