[1] Med Sans Frontieres, Publ Hlth Dept, Amsterdam, Netherlands
[2] Med Sans Frontieres, Islamabad, Pakistan
[3] Med Sans Frontieres, Publ Hlth, Amsterdam, Netherlands
[4] Australian Natl Univ, Canberra, ACT, Australia
[5] Med Sans Frontieres, Khamer, Yemen
[6] Australian Natl Univ, Natl Ctr Epidemiol & Populat Hlth, Canberra, ACT, Australia