HEALTH-ASIA: Dengue Goes Rural

By Marwaan Macan-Markar Reprint | | Print |

Marwaan Macan-Markar

BANGKOK, Mar 23 2006 (IPS) - From being a tormentor of people living in tropical, humid cities across Asia, the lethal dengue-carrying mosquito is spreading its wings into rural areas. That, warns public health experts, could result in dengue fever adding to the list of diseases sapping poor village communities.

Concern is fuelled by the geographic shift of the dengue mosquito, which, unlike the malaria mosquito, has always been known for breeding in cities, and the inability of small rural health facilities to handle a surge in dengue cases.

”Rural health systems are not equipped to treat dengue patients and lack the basic equipment to diagnose, ” Prof. Duane Gubler, director of the Asia-Pacific Institute for Tropical Medicines and Infectious Diseases, at the Honolulu-based University of Hawaii, told IPS.

Hospitals treating patients with dengue fever are expected to identify which of the known four strains of the infection have infected the patients. Treatment includes regular testing of the patient’s blood to monitor the platelet count. Patients with the fatal dengue haemorrhagic fever (DHF) experience severe pain in the stomach, vomiting and bleeding from many parts of the body, including the nose and gums.

World Health Organisation (WHO) experts say that this new pattern of dengue’s spread has been marked over the past decade. It has been attributed to the changing lifestyles and the movement of populations between the rural and urban areas.

”It started out as an urban disease, but as urbanisation spread so did the mosquito. Over the last 10 years, dengue has become more of a disease of the poor in rural areas,” says Dr. Kevin Palmer of the WHO’s Manila-based Western Pacific Regional Office. ”People at risk live in areas with poor health services.”

Among the features of modern urban living that have helped spread dengue to the rural areas are containers that could collect water, such as jars, pots, flower vases, discarded bottles, tins and barrels.

According to the Geneva-based global health agency, two of South-east Asia’s poorest countries, Burma and Cambodia, have shown signs of the disease hitting rural areas as has been the case in South Asian countries such as India, Bangladesh and Bhutan.

The increasing presence of dengue in rural areas comes at time when countries are still battling the Aedes aegypti mosquito, which spreads the disease, in cities, add WHO officials.

These concerns will frame some of the discussions due to take place during a two-day international meeting, which gets under way on Wednesday in Thailand’s northern city of Chiang Mai, to assess current dengue prevention and control efforts in Asia and the Pacific region,

Currently, an estimated 50 -100 million cases of dengue fever are reported every year across the world, of which some 500,000 are DHF cases, according to a WHO background note. Some 25,000 deaths are reported to occur annually due to DHF.

There has also been a spike in the frequency with which dengue is reported in the tropical countries in the world. ”About 50 years ago, epidemics of dengue occurred every 10-20 years. Now the epidemics are reported every 2-3 years,” adds the WHO note. ”In addition to older children, adults are being increasingly affected.

South-east Asia, in fact, was hit by a surge in dengue cases last year, ranging from cases in such affluent countries as Singapore to developing nations as Malaysia, Thailand, the Philippines and Indonesia. Singapore, often hailed for having a model dengue prevention programme, had over 11,000 cases in 2005, which was a record high.

Community involvement is paramount to control dengue, says Prof. Goh Kee Tai, of Singapore’s health ministry. ”Community ownership of the programme is important. Everybody in the community has to be mobilised.”

Thailand has mobilised tens of thousands of health volunteers to visit communities across the country to drive home that message. This Surveillance Rapid Response Team is also tasked to collect vital information about the strain of the dengue virus.

In addition to such a local, bottom-up approach to combat the dengue mosquito from breeding and spreading, funds from the international community and government are desperately needed to combat dengue, say the WHO officials.

”We need money for vector control, money for local authorities (to mount prevention programmes) and money to train doctors and nurses as each new batch comes out,” says WHO’s Palmer. ”Surveillance systems are weak and the information provided is sporadic. We only know when an epidemic is in progress.”

And the likelihood of a dengue vaccine coming to the rescue is still a distant prospect, says Gubler, the infectious disease expert from Hawaii. ”WHO made a commitment to develop a vaccine in 1977. They said it would take 10 years, but we are still waiting.”

Currently, there are five good vaccine candidates going through pre-clinical trials, Gubler he adds. ”We would like to think that we would have a good vaccine candidate in seven years. But don’t hold your breath.”