The flu, or influenza, is a viral infection that impacts the respiratory tract. It is a highly contagious infection that tends to occur seasonally. KidsHealth.org points out that most cases of the flu appear between late December and early March, but the flu season begins in November and ends in early March. Because the flu is caused by a virus, treatment focuses on providing comfort for and monitoring the infant.
Sudden Illness
KidsHealth.org explains that caregivers may notice that the onset of flu symptoms in infants can be sudden. The flu shares many symptoms with the common cold, but this sudden worsening of symptoms is more characteristic of the flu than a cold.
Fever
For approximately the first five days, the infant is likely to have a fever. Very young infants are not as likely to shiver with a fever, but older infants and toddlers may. The March of Dimes explains that fever appears suddenly and is often higher than 101 degrees Fahrenheit. Depending on the age of the infant, immediate medical attention may be necessary for fever. Infants younger than 3-months-old with a fever higher than 100.4 degrees, infants between 3 and 6 months with a fever higher than 101 degrees and children older than 6-months-old with a fever above 103 degree Fahrenheit all require medical intervention, per the March of Dimes.
Pain
Pain is difficult to recognize in an infant. The flu often causes muscle aches and sometimes abdominal cramping with nausea, vomiting or diarrhea. Headaches are common in older children and adults with the flu, but not as much in infants. Caregivers can recognize pain in infants by looking for arching of the back, persistent irritability and seeming to be inconsolable. Even when held, the infant may cry or curl up to protect the body from touch.
Fatigue
Sleeping longer and more frequently are signs of many types of illnesses. If an infant seems to be lethargic or difficult to wake, emergency treatment is necessary. Weakness or a lack of interest in playing are common signs of the flu in infants.
Appetite
The overall discomfort the infant experiences with the flu can impact the appetite. The baby may refuse to eat or seem overly fussy when being fed. Caregivers should monitor the infant's urine output. Dehydration is a serious complication of the flu, especially in infants. Some signs of dehydration include darkness under the eyes, sunken soft spot on the head, few wet diapers and crying without tears.
Respiratory Illness
The flu can cause a dry cough and a runny nose in infants. The March of Dimes warns against giving infants over-the-counter cold medicines as they can have serious side effects. Overall, the symptoms of illness tend to last about five days. Infants who have trouble breathing or a cough that lasts more than a week should follow up with a doctor. Pneumonia is one possible complication of the flu.
