 Daraasaddan oo uu sameeyay David Lawson oo katirsan mac-hadka nadaafadda ee London School of Hygiene oo soo xiganaya mac-hadka kale ee National Academy of Sciences journal ayaa tusaale usoo qaatay dalka Tanzania oo uu sheegay in ragga guursaday dumar badan ay ka hanti badan yihiin ragga qaba hal xaas oo kaliya. 