There was no information about cause or transmission... just a mandatory immunization program,
Kh#244;ng h#7873; c#243; th#244;ng tin g#236; v#7873; nguy#234;n nh#226;n... ch#7881; c#243; m#7897;t ch#432;#417;ng tr#236;nh ch#7889;ng d#7883;ch b#7855;t bu#7897;c.