Why is it Africa's men infidelity is taken lightly why that of women are taboo?

Well, I think that is just your opinion not fact, there is no culture i know in Africa that condones infidelity whether man or woman, what happens to women just like any other things when it comes to Family they on their own tend to be careful in facing the issue when it occurs so it doesn't lead to the man bringing in the woman he dates.
I heard a case where  a lady angrily left her husband because of infidelity and next thing the man did after some few attempts to bring her wife back , was to go and brought the lady in question into the house. After his wife finally forgave and made up her mind to return this outside lady is pregnant for her husband.

 So because of a case like this women don't push much when an incident of infidelity is found.
Also want to add that isn’t peculiar to any country or continent as your title suggested.

Yes, that doesn't imply that men are immune to infidelity as Martina title suggested.   I nearly fall from my chair when I saw this title. 

I have just read a 'scientific' article which claims that men are created like that. In other words, they cannot live with just one partner so they naturally search for more females. I thought to myself my oh my, now they are even trying to 'scientifically' justify infidelity. Imagine...