LETTERS

Corrigendum

In Vol. 84, issue number 3, 2006, page 181, the correct affiliations for the sixth author of this paper, Yohannes Kinfu, should be "Australian National University",Camberra,Australia,and ACDIS,Africa Centre,University of KwaZulu-Natal, Durban, South Africa". The name of the eleventh author was incorrectly spelled; it should read "Kubaje Adazu".