The genome of influenza viruses is generally divided into eight separate strands while that of the SARS virus is compact. The structure is different, and because it is a new virus, no one in the world has any antibodies against it. The virus is thus surprisingly lethal.
一般流感病毒固定有八段基因，而 SARS 病毒卻只有一條基因，構造不同，但因是新型病毒，全人類都沒有抗體，故而造成驚人的殺傷力。