The first cases of H1N1 , also called swine flu , were confirmed in Mexico in April . Officials in Chiapas delay school in effort to avoid flu resurgence . 1.55 million students affected , 850,000 of them in elementary school . Comment:
Officials in Chiapas delay school in effort to avoid flu resurgence . 1.55 million students affected , 850,000 of them in elementary school . Comment: