The mosquito-borne disease dengue has become unstoppable due to climate change, according to global health experts who advised nations to institute more aggressive elimination drives to stem the disease that sickens over 50 million and kills 24,000 worldwide every year.

Cold temperature kills adult mosquitoes, including their larvae, limiting the population of dengue carrying mosquitoes. However, global warming has disrupted this natural procedure, resulting to increased mosquito populations and consequently of dengue worldwide.

The World Health Organization said tropical countries like the Philippines are particularly at high risk.

A recent four-day symposium hosted by the Novartis Institute for Tropical Diseases (NITD) in
Mandaluyong City brought together leading dengue experts including scientists that discussed the growing global presence of the disease as they struggle to find solutions, including vaccines to prevent its spread.

NITD is a Singapore-based nonprofit research facility devoted to finding medicines to treat “neglected” infectious diseases.

Dengue fever is transmitted through the bite of the Stegomyia albopticus (formerly known as Aedes
Aegypti) mosquito and is characterized by a sudden onset of fever, weakness, headaches, nausea, vomiting, eye, joint and muscle pain, and rashes.

There are four known strains of dengue, considered the second deadliest mosquito-borne disease next to next to malaria.

"Temperature is only one of the many complex factors in the transmission of the disease. The major drivers of global dengue are population growth, modern transportation and lack of effective mosquito control," Dr. Duane Gubler, Director of the Asia Pacific Institute of Tropical Medicine and Infectious Diseases, told delegates during the symposium.

In the Philippines, Health Secretary Francisco T. Duque III revealed that the Philippines experienced an alarming rise in reported dengue cases in 2007 when there were over 45,300 cases and 416 deaths. It was the second worst year for dengue following the first one in 1998.

"It was a pattern that was unusual because we were reporting dengue even at the start of the year – outside of the peak season. And what's more, the cases were bursting out of the usual 3- to 5-year epidemic cycles," Duque said.

"Dengue had thus become a virus that was misbehaving out of its niche and a frightening year-round public health threat."

The health chief said the Department of Health began a more “aggressive assault against dengue in 2006 through a large-scale vector eradication and public education programs”.

Duque said although the Philippines lacked the important diagnostic tools, drugs and vaccines against dengue, the DoH relied on working with local governments and community leaders in eliminating stagnant water and other possible mosquito breeding sites.

"Education was the only tool that we have and prevention, our main focus. While we have had some success for the first time in four years to put the brakes on the accelerating trends of dengue, work is needed to develop new approaches for dengue and to understand the disease more clearly to reduce its toll and to improve its outcomes in clinical management," he said.

Duque revealed that there is a 37 percent decrease in reported dengue cases as of August 2009 compared to the same period last year.

As of September 1, there are a total of 16,317 dengue cases reported nationwide compared to the same period last year when a total of 25,969 dengue cases entered the dengue disease surveillance report of the DoH.

The areas that posted the highest dengue cases this year are NCR, Davao del Sur, Batangas, Rizal, Iloilo, Guimaras, North Cotabato, South Cotabato, and Nueva Ecija.