42 months ago

Dear Doctor,With a population of 9 Million we had 2500 new cases of Gonoorhea (G.) last year in Switzerland where I live. Based on your answers from the previous exchange of questions with you I have calculated a guesstimated risk for getting infected with G. by receiving oral sex without deep throating from a white female between the age of 18 and 65 .

I am very interested to hear from you if you find anything wrong with my calculation as the result is truly different from the common perception of the level of risk of contracting G. from receiving oral sex.

1.       I have excluded persons from 0-18 and 65 till 95 (50 % of population). Remaining 4.5 Million People and 2500 infections G. per year.

2.       60 % of women (2.7 Million ) got 1500 infection and 40 % of men ( 1.8 Million )got 1000 infections.

3.       From the 1000 infections of the 1.8 Million men 20 % (200) are caused by receiving oral sex while the other ones are from vaginal (400)  and anal (400). I have accounted oral sex to be half as risky as anal/vaginal and therefore took 50 % of the number of anal and / or vaginal.

4.        However  the risk to contract Gonoorhea from JUST ONE encounter (instead of multiple encounters )with a woman who is infected with oral G. is just 5 % (20 % for vaginal and anal ) of the normal risk . Remaining infections 5 % from 200 =10

5.       Conclusion : Risk for contracting G. by receiving normal oral sex with deepthroating  is

10 : 1.8 Million or 1 : 180 000 per year

6.       BUT : If the oral sex is performed without deepthroating the risk is only 5 % of the risk of normal oral sex with deepthroating. Remaining infections are then ONLY 0.5 cases for 1.8 Million men PER YEAR.

7.       Conclusion : Risk for contracting G. by oral sex without deepthroating 1 :3.6 Million PER YEAR.

8.        However if you calculate the risk on any given day of the year then the risk is 350 times smaller and only  1:  1.26 billion basically ZERO.

Can you agree broadly on these numbers ?


Edward W. Hook M.D.
Edward W. Hook M.D.
42 months ago
You are playing mathematical games here.  If you are expecting me to tell you that there is no risk for gonorrhea from receipt of oral sex, that is not going to happen.  On one hand, as you have demonstrated, if all gonorrhea was diagnosed and treated, AND if all new partnerships were at equal risk, your calculations would be at least of a similar order of magnitude as you calculate.  Indeed, particularly in Switzerland overall gonorrhea is uncommon and thus the risk of infection is low HOWEVER, some gonorrhea is likely treate without specifically being diagnosed or reported and some persons are at higher risk to be infected than others (commercial sex workers for instance).   Nonetheless, you are correct that, for any specific exposure, the risk of getting Gonorrhea is quite low.