Mobiles outnumber PCs
The diagram has two sections, the top one shows the infection rates for PCs and the bottom one for mobile devices (but not laptops which are counted as PCs). Note that the number of PCs and mobile devices in the USA is broadly similar at around 200m units which is why the circles are the same size in both the top and bottom sections of the diagram. The same is also true for Western Europe and Japan. Now look at China, where the situation is very different. There are eight times more mobile devices in China than PCs and in India and Nigeria this ratio is even greater.
The conclusion is that while the cyber threat is normally seen as a PC based issue for developed economies in the West, in reality it is a much more serious issue for mobile devices in emerging markets. China is the manufacturing centre of the world, as India is for IT and outsourced services. There are few companies in the world that do not use goods or services that originate from one of these two countries. These high malware infection rates should be borne in mind whenever communicating or transacting online with these countries.