Recycled airplane air makes readers sick

DEAR DR. GOTT: My husband and I seldom get colds, but every year we spend 14 hours in airplanes on our way to Eastern Europe and, inevitably, we both come down with colds within a week to 10 days after arrival.     Last time my cold developed into a very bad case of bronchitis, and my husband lost days of work. I firmly believe it is something we catch from the recycled air on the planes. Would wearing a surgical-type mask stop a cold virus? I know it wouldn’t be very easy to wear one on such a long flight, but then, neither is being sick when you are halfway around the world. What would you suggest to avoid this problem in the future?
    DEAR READER: Airline companies, in an attempt to conserve energy, have altered the pattern of in-flight air recycling. This saves fuel but means that infectious micro-organisms can contaminate the cabins easily, and these germs are undoubtedly new to you and your husband. Such viruses and bacteria can be prevented from entering the respiratory tract. I do not know of any other way to avoid exposure.
    This is a common occurrence and does not necessarily reflect an immune deficiency or other health problem.
    DEAR DR. GOTT: I have a question about blood-pressure machines. Is the wrist type as accurate as the upper-arm machine?
    DEAR READER: In my experience, the wrist blood-pressure unit is not as accurate as the standard upper-arm type. However, the wrist readings are often appropriate for home monitoring in conjunction with periodic upper-arm determinations.