The H1N1 influenza A virus has claimed 1,154 lives worldwide since it first emerged in April 2009, according to the World Health Organization (WHO).

The WHO said that 168 countries had been affected by the H1N1 virus as of 31 July 2009 and the number of laboratory-confirmed cases reached 162,380 globally.

The number of cases reported understates the actual number as countries no longer need to report individual cases, the WHO said.

The most cases (98,242) were identified in the Americas with 98,242 people diagnosed, followed by the Western Pacific with 26,661 sufferers and Europe, where those with the virus total 26,089.

The Americas also registered most number of deaths, with 1,108 killed by the virus, according to the WHO data.