The organization said 13 countries had adopted preventive measures, including the temporary closure of schools and universities, affecting 290.5 million students worldwide.
Iliripoti kuwa nchi 13 zilikuwa zimeweka hatua za kuzuia ugonjwa ikiwemo kufungwa kwa muda kwa shule na vyuo vikuu, iliyoathiri wanafunzi milioni 290.5 kote duniani.