Just for the record MSF is a "Secular" charity, not an "Atheist" charity.
There is a huge difference and I'm sure many of it's members have religious beliefs, which is totally irrelevant to MSF's activities.
While the official line is that MSF are independent, the truth is that they are highly critical of any religious policy which conflicts with commonly accepted medical practises, such as wearing a condom to prevent transmission of HIV. They are independent in the sense they favour no religion, nor are they officially an atheist charity, but the belief systems of many involved are definitely leaning towards anti-religion. Most charitable-minded people who have strong religious convictions don't offer their services to MSF, they sign up to the charitable cause associated with their faith.