The last several months have been tough on many families with infants and toddlers. By this time of year, the average infant or toddler who attends preschool or child care (or has an older sibling who does) has likely had between six and twelve respiratory infections since the fall.
Respiratory infections can vary from mild cold viruses and ear infections to throat infections, croup, and lung infections. Studies consistently show that young children who are around other young children average two respiratory infections per month during cold and flu season. With slight variations from year to year, cold and flu season in Richmond typically lasts from sometime in September through March or early April. When factoring that each new infection can last upwards of ten to fourteen days in young children, this adds up to somewhere between twenty and twenty-eight days of symptoms every month, for roughly half the year. Parents are not far off when they say it seems like their child is sick all the time.
These statistics are not meant to scare parents but rather frame their expectations for what has undoubtedly been a long six months. Clichés like “it’s just another cold” and “it helps build immunity” provide little consolation when you are a parent of an infant or toddler who’s struggling to breathe through their nose due to perpetual congestion or wakes up coughing most nights due to the constant post-nasal drip that is amplified when they lay down. During the winter, exhausted parents spend a lot of time at the pediatrician’s office. They just want their child to be well, to make it an entire week without having to pick up their child early due to illness, and to remember what it feels like to get a few nights of good sleep in a row. Amidst all of this, parents cannot help but wonder: Is there something wrong with my child’s immune system? How many infections is too many?
How Baby’s Immune System Works
It may be helpful to understand how the immune system develops in the first two to three years of life. In the early days and weeks, an infant’s immune system is relatively weak. To fight infections, young infants rely on antibodies that were transferred through the placenta before birth, antibodies transferred in breast milk, and through herd immunity of their loved ones whose own immune systems have developed strength through fighting germs and receiving vaccinations. As early as six weeks (though more commonly at the two-month checkup), infants receive their first series of vaccinations against respiratory germs. These vaccines stimulate infant immune systems to develop protection against some of the most serious respiratory germs – ones that cause life-threatening infections like whooping cough and meningitis. Now primed, their young immune systems begin to do a better job fighting common, everyday infections like cold viruses. This is reassuring because as the child ages and begins interacting with other young children, there is no shortage of germ exposure. With stimulation from each new infection and each dose of vaccine, the immune system develops greater memory and gets stronger. Then, when the germs appear in the future, the immune system can recognize this more quickly and fight the infection more effectively and efficiently.
With this in mind, how many respiratory infections are too many? Perhaps, this question oversimplifies a complex issue. More appropriate would be one of the following: 1) How do we know when a child has been sick more frequently or persistently than expected based on age, time of year, and germ exposure? or 2) How do we know when a child’s immune system is responding appropriately to infections?
In addition to persistent respiratory symptoms, pediatricians are monitoring those infants and toddlers who are not growing well, who require hospitalization and IV antibiotics to clear a bacterial infection, who have taken two or more cumulative months of oral antibiotics with little effect, who have non-healing wounds or chronic diarrhea, or who have a family history of immunodeficiency (i.e. weakened immune system). If one or more of these conditions apply to your child, contact your pediatrician to discuss whether bloodwork might be helpful to assess your child’s immune system. If none of these conditions apply to your child, their immune system is likely working the way it is supposed to – it just needs more time and experience.
