Imported goods and overseas travel mean Bermuda is at constant risk of bringing the deadly dengue fever to the Island, Chief Medical Officer John Cann said.

He was speaking after an infectious diseases conference in Argentina heard cases of the fever are increasing in almost every country in North and South America, with numbers doubling from 1997 to 1998.

Bermuda has been free of the fever since 1941 when a scorched earth policy was taken to rid the Island of the mosquitoes which carry it, but the insects returned in 1998.

None of the mosquitoes are carrying the infection and no one on the Island has the virus. The virus is transferred if a mosquito bites an infected person and then passes it to another human.

But Dr. Cann said the Island was vulnerable to importing the disease if people travelled overseas to infected areas, and because Bermuda imported most of its goods.

He told The Royal Gazette yesterday: "There is still mosquito activity in Bermuda which we are keeping under surveillance, but we don't have a pool of infected people.

"The real risk might be people travelling to infected areas who come back sick and don't go to their doctors and the mosquito could bite that individual and then infect another person.

"We've been free for decades, but with international travel and the way we transport our goods, we run this risk.'' In late 1998, mosquitoes were found on the Island for the first time since 1941. The Island was devastated in 1941 when 1,501 were infected and 17 killed.

In 1998, Environmental Health officers identified breeding sites in Warwick, Paget, Pembroke and Southampton.

Members of the public have been warned not to leave water lying to prevent the mosquitoes laying their larvae.

A half inch of water is enough for the mosquitoes, which have white bands on their bodies, to lay their larvae.

Dengue fever, for which there is no vaccine, causes excruciating muscle and joint pains, high fevers and severe headaches. Its more virulent form called haemorrhagic dengue can cause internal bleeding and death.

The disease was almost wiped out in 1962, but cases are increasing in almost every Western hemisphere country except Bermuda, Canada, Chile and Cuba.

Eric Martinez, a specialist in dengue fever, told the International Congress on Infectious Diseases in Buenos Aires that a lack of coordination between and within governments, dwindling resources and declining awareness of the problem had led to a resurgence in the virus.

Dr. Martinez, a Cuban, said: "If we continue with our present conditions, we're going to have serious problems.'' According to the US Centres for Disease Control and Prevention (CDC), the number of cases of dengue fever in the Americas more than doubled to 741,794 in 1998 from 364,945 in 1997.

Even in the United States there were 90 laboratory diagnosed cases of dengue in 1998, including one death.

Dr. Martinez said socioeconomic conditions, public health services and preventive and vigilance programmes must improve to combat the mosquito and the disease.

"If these things don't occur, and presently they aren't, at the doors of the 21st century, we will have to say that the 21st century will be like no other in terms of outbreaks and epidemics of dengue and haemorrhagic dengue.'' Global warming was increasing the geographical areas in which the mosquito can live, he said, adding: "This is a global problem.'' Francisco Pinheiro of the Pan American Health Organisation said community participation community awareness was the keystone toward prevention.

Argentina has recently increased its dengue awareness programmes fearing an outbreak of the disease at home after the number of cases in neighbouring Paraguay reached what the government there called an "epidemic explosion''.

The Argentine government has said Paraguay has about 10,000 confirmed cases of dengue in a country of five million people, with one fatality. In March, Argentina detected 170 cases of dengue, all Paraguayans or people who had been in the South American country.

Dr. Cann said he did not agree co-operation was a problem, particularly between Caribbean nations. Bermuda is one of 22 countries which receive information from the Epidemiology Centre in Trinidad.

He said: "I would not agree with that statement.

"There is a real effort to alert and take the steps necessary, certainly within the Caribbean. Through the Epidemiology Centre we get the alerts when there is viral activity and get constant reminders of the types of things individual countries and regions should do to combat this.'' Dr. John Cann CONFERENCE CON