The World Health Organization (WHO) said the Latin American country had registered 1,200 cases of dengue fever outbreaks, and 110 cases of dengue haemorrhagic fever by mid-June, and that the international community is in a period when incidence of the disease is high in a number of countries.

To prevent the fever from spreading to China, travellers from regions subject to dengue fever are being requested to declare at Chinese quarantine and inspection stations any symptoms such as fever, headaches, bone or joint and muscular pains and rashes that are associated with the disease.

The request was made in a bulletin issued yesterday by the State Administration of Quality Supervision and Quarantine.

If such travellers develop any of these symptoms after they enter China, they should get medical treatment immediately, said the bulletin.

Dengue is a mosquito-borne infection which in recent years has become a major international public health concern, and dengue haemorrhagic fever is a potentially lethal complication, according to information posted on the WHO's official website www.who.int.

No vaccine for dengue has yet been developed.

In another development, Brazilian scientists has said earlier this year that they had developed a bacteria-based product to eradicate larvae of the mosquito that transmits Dengue fever.

The product still needs approval by Brazil's health agency.

But Rose Monnerat, a researcher from Embrapa, Brazil's agriculture institute, predicted it will be available on the market by September.

To prevent such mosquitoes from entering China, Chinese quarantine authorities said all transport equipment and containers from dengue infected areas should be disinfected.

Quarantine officials yesterday also advised people who may be heading for El Salvador or other dengue regions to get the latest information about the disease from local quarantine agencies or health care centres.

China has no diplomatic relations with the Republic of El Salvador. The number of people travelling to the country is not immediately available.

Experts said travellers to El Salvador can take precautions to diminish the risk of contracting the disease, including wearing clothing that covers the body and using mosquito repellent.

The disease is found in tropical and sub-tropical regions around the world, mostly in urban and semi-urban areas.

Annually, there are 20 million cases of dengue infection across the global community, resulting in around 24,000 deaths, according to a WHO report.

(China Daily July 04, 2002)