FACTBOX - Some facts about the WHO's Int'l Health Regulations

(Reuters) - The World Health Organisation (WHO) on Saturday declared the swine flu outbreaks in Mexico and the United States "a public health emergency of international concern."

The decision was reached by WHO Director-General Margaret Chan after discussions with an emergency committee of experts. She used her authority under the International Health Regulations (IHR), which are overseen by the WHO, a United Nations agency based in Geneva.

Here are some facts about the International Health Regulations:

* Under the WHO's International Health Regulations, a public health emergency is of international concern if it constitutes a public health risk to other states through the spread of disease and potentially requires a coordinated international response.

* The IHR regulations, which entered into force in June 2007, are an international legal instrument that is binding on 194 countries, including all the member states of WHO.

* The regulations require countries to report certain disease outbreaks and public events to WHO. They also establish a number of procedures that the agency must follow in its work to uphold global public health security.

* They aim to help the international community prevent and respond to acute public health risks that have the potential to cross borders and threaten people worldwide. Such crises can result from emerging infections like Severe Acute Respiratory Syndrome (SARS), bird flu, or other emergencies such as chemical spills, leaks, dumping or nuclear meltdowns.

* The regulations also aim to limit interference with international traffic and trade.

(Compiled by Stephanie Nebehay)