Their experiments monitored 42 mouth organ players for varicocele rates and, as a control, compared them with 31 military-vehicle drivers (whose day-to-day work did not involve undue blowing). As hypothesised, the study revealed significant differences in the mouth-organ group :
“… the varicocele prevalence among wind instruments players has been higher than normal level, while it was normal for the drivers.”
“It seems that there is a relation between high rate of varicocele in music group and their type of activity involved with valsalva maneuver and long-term standings.”
See: Rezakhaniha B, Siroosbakht S, Mirzaii-Dizgah I. ‘Comparison of the Varicocele Frequency in Mouth Organ Musician and Drivers.’ Zahedan J Res Med Sci (ZJRMS) 2012; 14(6): 31-32.
 This video shows harmonica virtuoso (the late, great) Sonny Boy Williamson II performing “Keep It To Yourself”
 The (10x15cm) metallic picture as shown above – entitled ‘Muha Lady’ – is available from the Deutsches Harmonikamuseum (based in Trossingen, Germany) shop, for a very reasonable € 2,50