Combat Wombat writes: "The Mexican government says a strain of the influenza virus has killed at least 45 people and infected hundreds of others.
Seven non-fatal cases have also been confirmed in the United States.
Mexico's health ministry says the new virus has reached epidemic levels.
It was originally described as a form of swine flu, which had mutated and been passed to humans.
The US Centres for Disease Control and Prevention says closer analysis showed it is a never-before-seen mixture of swine, human and avian viruses.
Humans can occasionally catch swine flu from pigs but rarely have they been known to pass it on to other people.
Most of the cases so far recorded have been in or near Mexico City and have largely affected men between the ages of 25 and 44.
As well as ordering the closure of all schools in the capital and neighbouring Mexico states, the ministry is advising the population to avoid crowded areas and not to shake hands or kiss one another.
The World Health Organisation (WHO) says the virus has the same genetic structure as a new strain of swine flu, designated H1N1, seen in seven people in California and Texas."