FRIDAY, Jan. 21 (HealthDay News) -- People who use public
transportation have a nearly sixfold increased risk of developing
an acute respiratory infection that requires a visit to the doctor,
But, people who travel by public transit every day might be
somewhat more protected from acute respiratory infections than
occasional users of the transit system, the researchers at the
University of Nottingham in England found.
The study was conducted in Nottingham during an influenza
outbreak between Dec. 2, 2008 and Jan. 15, 2009. The researchers
asked 138 patients (72 with an acute respiratory infection and 66
controls) at a doctor's office about their use of public transit in
the five days before the start of respiratory symptoms or before
their medical appointment.
"We found a statistically significant association between acute respiratory infection and bus or tram [streetcar] use in the five days before symptom onset. The risk appeared greatest among occasional bus or tram users," Jonathan Van Tam, a professor of health protection in the School of Community Health Science and director of the Health Protection Research Group, said in a University of Nottingham news release.
"These data are very plausible when we think about the greater likelihood of developing protective antibodies to common respiratory viruses if repeatedly exposed. The findings have differing implications for the control of seasonal acute respiratory infections and for pandemic influenza. In the latter case we don't have an opportunity to build up any immunity beforehand because it's, by definition, a new virus," Van Tam said.
The study was published in the Jan. 14 online edition of the
BMC Infectious Diseases.
The American Academy of Family Physicians has more about
colds and the flu.