With more than 700 people around the world dead from swine flu since the outbreak started four months ago—an increase of at least two-thirds from the last official death toll of 429, published July 6 by the World Health Organization—swine flu could be the biggest flu pandemic ever seen, says Margaret Chan, director-general of the WHO. Luckily, most cases are still only producing mild symptoms like headache, runny nose and sneezing; the great majority of people won’t even require medical attention before recovering, the BBC reports. About 125,000 confirmed cases have been reported globally, although the number certainly exceeds that; but the WHO says it’s pointless to identify every new H1N1 case, as the pandemic is developing so fast. In past pandemics, flu viruses took over six months to spread as widely as this virus is spread in under six weeks. School closures are among several recommendations being looked as, as the flu is expected to surge in the Northern hemisphere in the fall, when the weather cools.