Rapid rise of dengue cases in the Philippines as Government declares national alert
Dengue cases continue to surge in the Philippines, with over 100,000 dengue cases and more than 450 deaths reported by the Department of Health (DOH) from 1January to 29 June 2019. On 15 July, the DOH declared a National Dengue Alert, urging its regional offices to step up surveillance, case management and outbreak response.
Reported dengue cases are an 85 per cent increase from the same period last year, and the deaths mostly children from five to nine years old. Because children do not have immunity to dengue yet and are more prone to infection, they are the most affected by the disease and there is no antiviral treatment available beyond supportive care. In 2017, the Philippines Food and Drug Administration (FDA) suspended the license of the dengue vaccine Dengvaxia in 2017 following a controversy regarding a DOH school-based dengue vaccination campaign. In 2019, the FDA announced that it permanently revoked the license to import, sell, or distribute Dengvaxia in the Philippines.
According to a WHO Philippines situation report, the case fatality rate of 0.43 per cent is significantly higher than the regional average of 0.22 per cent in the Western Pacific, and has placed the risk assessment as high at national level, and low at regional and global level.
Several regions in the Philippines are at epidemic levels of dengue
Regions which have exceeded the epidemic threshold, which is the critical number required for an epidemic to occur are MIMAROPA, Western Visayas, Central Visayas, and Northern Mindanao. Other affected regions are the Cordillera Administrative Region, Calabarzon, Bicol, Eastern Visayas, Zamboanga, the Bangsamoro Autonomous Region in Muslim Mindanao (BARMM) and Metro Manila. The provinces of Iloilo, Capiz, Aklan Antique and Guimaras in the Western Visayas region declared an outbreak, with many municipalities seeking to declare a state of calamity to access emergency funding to mobilise additional resources. Regional health authorities are identifying clustering of cases as a basis for declaring a localized epidemic at the barangay (village) level.
Urbanization, climate change contributing to the spread of dengue
Several Asian countries are experiencing unusually high numbers of dengue cases for this time of year. According to the World Health Organization, of out of an estimated 2.5 billion people at risk for dengue globally, about 70 per cent live in Asia Pacific countries. Cambodia, the Lao People’s Democratic Republic, Malaysia, the Philippines, Singapore and Viet Nam have observed early increases in the number of dengue cases reported so far this year. In the Asia Pacific, climate conditions, unclean environments, unplanned urban settlements and rapid urbanization can lead to increased mosquito breeding in communities. According to Dr. Gawrie Loku Galappaththy, Medical Officer for Malaria and other Vector-borne and Parasitic Diseases of WHO Philippines, a variety of factors can contribute to the increasing dengue cases in the Philippines. “The onset of El Niño has led to drought and water shortages in some provinces in the Philippines. Due to water shortages, people collect water in containers for general use, increasing the likelihood of dengue mosquito breeding places,” said Dr. Galappaththy. “The increased awareness on dengue, and the general population is seeking health care promptly, therefore the reporting has increased,” she said. “Dengue is also a cyclical disease, which means there is an expected increase of cases every three years.”
Government action and humanitarian response
On 15 July, the Department of Health declared a National Dengue Alert, urging regional DOH offices to step up dengue surveillance, case management and outbreak response in health facilities and hospitals, as well community and school-based health education campaigns, clean-up drives, and logistics support for dengue control. In coordination with the National Disaster Risk Reduction Management Council (NDRRMC), a code blue alert was raised, activating the national Health Cluster led by DOH.
WHO is supporting the DOH with epidemiological analysis and rapid risk assessments, preparing targeted risk communication messages for health workers and communities to ensure early detection, and DOH surveillance units at municipal, provincial and regional level are proactively looking for clusters of dengue cases to launch specific response activities. Rapid diagnostic tests are also being distributed to barangays (villages). WHO is also providing technical assistance to update the clinical management guidelines on dengue patients to reduce mortality, support risk communications, advice on dengue vector control, and orient provincial level staff on outbreak response for dengue. The DOH is also undertaking a nationwide public information campaign to follow the ‘4-S method’ which stands for “Search and destroy” mosquito-breeding sites, employ “Self-protection measures” such as wearing pants and long-sleeved shirts, and daily use of mosquito repellent, “Seek early consultation”, and “Support fogging/spraying” in areas where an increase in cases is registered for two consecutive weeks to prevent an impending outbreak. The Philippine Red Cross is also ramping up its information campaign on dengue, conducting house-to-house visits, health seminars, and facilitating blood donations in some provinces.
Multi-sectoral response needed to fight the rise of dengue
According to WHO, one of the most effective measures to prevent dengue is by reducing mosquito breeding sites at the community level. Dengue mosquitoes like to breed in containers that collect water such as tires, bottles, and coconut shells. Communities can clean their surroundings, empty and wash water containers and dispose unused containers that may accumulate water.
“Dengue control is not just up to the health sector. It can only be successful if different sectors work together,” says Dr. Galappaththy. “The local government is extremely crucial in pushing for vector control at the community level, while the education sector can assist in health promotion and vector control at school settings.”