Dispelling myths about viruses

It was one of those winter weeks where so much influenza was floating around that I was starting to assume each sick child had flu until proven otherwise.

Saturday morning, a little patient was brought in by her father after she woke up with a moderately high fever, annoying cough and runny nose. Much to the little girl's dismay, a nasal flu swab was performed and the rapid test did come back positive for influenza A.

Her father had three possible sources for his daughter's illness. “She went out in the cold yesterday without wearing her hat,” he offered, “plus she swam in pool water two days ago. And, she was playing with kids with colds at last night's party.” I told the dad that though his leads were all very intriguing, his little girl had probably picked up flu from one of her classmates during the past school week.

As instructors at the Harvard Medical School explain, being outside in the cold weather does not give kids colds and flu. Frigid temperatures do, however, drive families inside where they hang out with others and easily share viruses in close quarters. Influenza also appears to spread best in the low humidity and low temperatures of the winter months.

As for chlorinated swimming pool water, in Flu Questions and Answers, experts at the Centers for Disease Control and Prevention state that “there has never been a documented case of influenza virus infection associated with water exposure.”

The CDC does note that, as with all busy public places, swimming pools can be a venue for person-to-person viral spread since children tend to cough and sneeze on each other. Also, since the influenza virus can survive on surfaces for up to two to eight hours, the virus can be transmitted when kids touch a contaminated object and then touch the mucous membranes of their nose or mouth.

Influenza is generally spread within one to four days of exposure to an infected person. So, I also thought it was more likely that my preschool patient caught influenza from classmates during the previous school week rather than from the little friends that sneezed on her during the birthday party 12 hours prior to the girl's first signs of illness.

Not long after seeing my little influenza patient, I examined two other patients, both 2-years-old and both exhibiting fevers and upper respiratory symptoms. It turned out neither of these patients had influenza, and neither showed any signs of serious infection.

I recommended comfort measures for the first toddler, and the father was fine with this advice and assured me that he was keeping his daughter hydrated, but was being very careful to avoid milk. Since the little girl had no history of milk allergy or any past experience of increased congestion with dairy intake, I told dad that it was actually OK to offer his daughter milk during this upper respiratory tract illness.

In an interesting article in the online journal Medical Hypothesis, New Zealand researchers Jim Bartley and Susan McGlashan, find that though it's a widely held belief that excessive milk intake is associated with increased respiratory tract mucus production and asthma, the medical evidence for this link is limited. The duo hypothesize that only a subgroup of patients will find that asthma or rhinitis symptoms improve when dairy is eliminated from the diet.

• Dr. Helen Minciotti is a mother of five and a pediatrician with a practice in Schaumburg. She formerly chaired the Department of Pediatrics at Northwest Community Hospital in Arlington Heights.