State health departments in the US are better than local departments at sharing information about the influenza A H1N1 virus with the public, according to a new study.

The RAND Corporation study published in the journal Health Affairs found that 46 of the 50 state health departments posted information about the H1N1 outbreak within a day of it being declared a public health emergency.

Only a third of the 153 local health departments surveyed posted information on their websites within a day of the declaration, the study said.

Researchers from RAND Corporation, a nonprofit research organisation, said that the flu outbreak provided a rare opportunity to analyse the performance of state and local health departments during an emergency.

RAND senior economist and lead author of the report Jeanne Ringel said that the capability to conduct basic crisis and emergency risk communication was quite good at the state level but there was a significant variation at the local level.

Information on health department websites should be provided in multiple languages to cater to a more diverse audience, the researchers said.