I was never paranoid about germs before my stem cell transplant.  Now that I have a compromised immune system, I have turned into a germaphobe.

My transplant doctor has warned me that flying can be deadly for stem cell patients when their neutrophil counts are particularly low.  First, there is the fact that most air in a plane is re-circulated.  It takes too much fuel for an airliner at 30,000 feet to pressurize and heat fresh air.  That means you are breathing the same air that the guy 10 rows in front of you was breathing when he sneezed or coughed.  That’s why my doctor will not allow me to fly without a surgical mask and he discourages me from flying three out of four weeks per month when my ongoing chemotherapy schedule makes my blood counts drop.

Then there’s the fact that airline crews do not have the time to clean seats and tray tables between flights.  CNN reported that airline seatback tray tables have an average of 2,155 colony-forming units (CFUs) per square inch.  That’s compared to 70 CFUs per square inch for airport bathroom door latches.  I heard an interview with a flight attendant last week in which she shared that she often sees parents changing their baby’s diapers on the tray tables.

I learned recently that cruise ships are off limits for stem cell patients like me.  Mary Pat and I planned a cruise to Alaska with my brother Mark and his wife Denise to thank Mark for donating his stem cells for my transplant.  When Dr. C found out about our plans he strongly urged that we cancel them.  He started his career as a ship’s doctor and is aware that medical officers on ships do not have the right drugs and medical facilities to treat an immunosuppressed patient with a systemic infection.  In addition, the hospitals at most ports of call in Alaska are probably not experienced in treating stem cell transplant patients who need specialized antibiotics and antivirals.

According to a Today.com report, in 2014, 1,766 passengers and crew members reported gastrointestinal illness outbreaks aboard a total of nine cruise ships.  An undercover team took a germ meter on a cruise to the Carribean and swabbed a serving spoon at the ship’s buffet.  The result was a reading of 2,102.  Health experts consider any reading over 100 as a fail.

The bottom line for stem cell transplant patients appears to be that you’d better wear your surgical mask on planes, you shouldn’t touch the tray back tables, you should avoid cruise ships, and you should invest heavily in hand sanitizers.