§
Media = Press, news aggregators and blogs.
* Systems = another biosurveillance system included in the study.
#
Official = official sources and expert contributions.
£
Sub-Sah. Afr = Sub-Saharan Africa.
‡
N. Afr.- N.East = North Africa and Near-East.
¥
VHF = Viral Haemorrhagic Fever.