It is estimated that the infection rate is 2 percent in Britain, 4 to 6 percent in France, 8 to 10 percent in the United States, and 13 percent in Japan.
Arvestuste kohaselt on Suurbritannias nakatumise määr 2 protsenti, Prantsusmaal 4 – 6 protsenti, Ameerika Ühendriikides 8 – 10 protsenti ja Jaapanis 13 protsenti.