The number of confirmed cases of swine flu or A (H1N1) virus has increased to 5,251, with 61 people dead from the disease around the world, the World Health Organisation announced on Tuesday.
According to latest WHO update, Mexico and the US have topped the list of 30 countries where laboratory-confirmed human cases of the virus have been reported. Mexico has 2,059 cases with 56 deaths while the US has 2600 with three deaths.
Canada has 330 cases, including one death, while Costa Rica has eight cases, including one death.
"WHO's pandemic alert level remains at Phase 5 -- on a six-point warning scale -- as it has for the past several days," Dr Keiji Fukuda, WHO's acting assistant director-general for health security and environment said.
"Community-level sustained human-to-human transmission has been documented in North America, in Mexico and in the US most clearly. We do not see clear evidence of sustained community-level transmission going on in other countries yet," he said.
Dr Fukuda noted that it is possible that the alert level will go up to Phase 6, which would mean that the spread of the virus has become established in another region outside of North America and is spreading at the community level.
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