by Andrea Therese Canivel
The Los Baños Municipal Health Office (MHO) continues to promote community sanitation efforts to prevent the spread of dengue notwithstanding the free school-based immunization (SBI) program of the Department of Health (DOH) that started April this year.
The MHO warns against dependence on the vaccine for preventing dengue and emphasizes the importance of collective and pro-active action.
According to Wilma Estacio, a public health nurse and designated dengue surveillance officer at the MHO, community participation and cooperation are necessary in combatting the threat of dengue. She said that the availability of a vaccine should not be reason for complacency. “Talagang kailangan ng community participation kasi hindi naman yan kaya lahat ng vaccine,” she said.
The SBI targets over one million Grade 4 students in Regions III, IV-A, and NCR where the highest dengue incidence have been recorded in the country. In an epidemiological study of dengue from 2000-2011, it was found that children aged 5–14 years old represent the age group with the highest proportion of dengue in the Philippines. In Region IV-A, Laguna is second to Cavite in terms of recorded cases.
Data from Wilson Gascon of the LB MHO
In Los Baños alone, the MHO recorded a total of 328 cases in 2015. In the past three years, there have been a total of 1,018 reported cases, with the highest count of 453 occurring in 2014.
Among the 13 barangays in Los Banos, Batong Malake has the highest recorded incidence in 2015 with 56 reported cases, a significant decrease from the 2013 and 2015 statistics of 88 and 83, respectively. The same barangay also had the highest incidence in the past three years, averaging 76 reported cases annually.
Data from Wilson Gascon of the LB MHO
Through SBI, students will receive the first of three shots under this initiative.
Anita Dorado, a nurse serving as childcare coordinator at the Los Banos MHO, finds the timing of the program challenging because the school year has ended for most of the elementary schools. “Sa school ang first round namin [of vaccinations]; ang first dose ay April or May or June… Ang problema nila (DOH) ay sa estudyante na mahahagilap nila ng April-May kasi bakasyon,” she said.
In Los Baños, the MHO is in charge of administering the vaccine to students. Scheduling and identifying students for vaccination is the task of the DOH.
Prevention
In the midst of challenges in the implementation, the Los Banos MHO continues to promote the “Search and Destroy” component of the DOH strategy 4 S Kontra Dengue, which summarizes the four ways by which dengue can be prevented. The 4 S stand for the following: (1) search and destroy; (2) self-protection measures; (3) seek early consultation; and (4) say ‘no’ to indiscriminate fogging.
Search and destroy entails emptying and keeping dry all possible containers of stagnant water where mosquitoes can lay eggs. This step means looking for possible breeding sites of mosquitoes and emptying them of water, such as flower vases, water storage (e.g., drums and buckets) gutters, clogged canals, empty tin cans, and tires. Estacio said that even dish draining racks can be potential breeding sites of mosquitoes.
According to Dorado, keeping the surroundings clean is an important step toward health as it prevents not just dengue but also other diseases, particularly those brought by mosquitoes. Other mosquito-borne diseases include the Zika virus, yellow fever and chikungunya.
Self-protection means personal care to avoid exposure to and being bitten by mosquitoes. Examples given by the DOH in existing campaign materials include wearing clothes that provide ample skin coverage, using insect repellents that usually come in the form of lotions or sprays, and using mosquito nets or kulambo.
Seeking early consultation means going to a health facility for check-up when symptoms of dengue show, such as fever lasting at least two days, red spots, abdominal pain, nose and gum bleeding, vomiting, and nausea. Depending on the result of initial evaluations or tests, appropriate treatment will then be prescribed. Symptoms of dengue may take three to seven days to fully manifest.
Saying ‘no’ to indiscriminate fogging means resorting to fogging only in times of imminent outbreak. Fogging entails the use of a synthetic pyrethroid similar to insecticide formulas found in common supermarket insecticide sprays. The fog discharged by the fogging machine is created by blasting very fine droplets of the insecticide and water mix into the air through the machines. While the amount of insecticide in the fog is completely harmless to humans because it is only present in small quantities enough to kill mosquitoes, indiscriminate fogging can make mosquitoes immune to the insecticide. According to the MHO, indiscriminate or too frequent fogging can cause the mosquitoes to develop immunity to the chemical. Dorado said that the health office conducts fogging only when there is high incidence or reported cases of dengue in a specific place.
In addition to promoting the 4 S to combat dengue, the MHO also teaches community leaders how to operate fogging machines and to observe the 4 o’clock habit of the DOH.
Sanitation personnel from the health office demonstrate to barangay councilors the proper use of these machine so the barangay leadership can conduct fogging as the need arises without having to wait for the sanitation officers.
They also continue reminding people about cleaning up their surroundings at 4 PM as a dengue-preventive measure. The DOH encourages the clean-up at 4 PM when dengue-carrying mosquitoes called aedes aegypti are most active.
Local initiatives
According to a 2013 DOH advisory, the best approach to correctly doing the 4 o’clock habit is the “stop, look, and listen” approach—(1) to stop or drop all other activities and focus on the dengue prevention activity; (2) look for or seek out possible mosquito breeding sites and get rid of the stagnant water, as also captured in the 4 S Kontra Dengue strategy; and (3) listen or pay attention to instructions and advisories of local authorities in implementing a synchronized 4 o’clock habit.
Dorado said that all barangays are aware about the 4 S and the 4 o’clock habit. “May ginagawa silang search and destroy talaga. Sa ibang barangay nakikita ko naman regular sila na merong parang naglilinis pati yung mga canals,” she said.
In barangays Lalakay and Putho, locals observe other preventive measures, such as ovicidal-larvicidal trapping or OL trapping. It involves everyday monitoring of a three-part kit designed by the Department of Science and Technology in 2010 to trap and kill mosquito larvae as soon as they are laid and to monitor the amount of mosquitoes in the area. The kit consists of a black container, a lawanit paddle or a strip of wood made from the wall of a coconut husk where mosquitoes lay their eggs, and a pack of pellets containing the larvicide used to make a solution that kills the eggs and larvae of mosquitoes.
The trap simulates the optimum conditions for a mosquito to lay its eggs: a dark area with clean, clear, stagnant water, as well as a rough and damp surface. The scent of the solution in the kit attracts female Aedes aegypti mosquitoes to lay their eggs on the lawanit stick that is half-submerged in the larvicidal solution created by the pellets.
Dengue is a disease endemic to the Philippines. A vector borne disease—which means that it is transmitted by insects, specifically through the bite of Aedes aegypti mosquitoes—it affects 110,000 persons annually. In 2015, the DOH recorded 142,227 cases in the first 11 months, from January 1 to October 31.
The vaccine
The DOH seeks to prevent dengue through vaccination. Dengvaxia is the world’s first dengue vaccine, which has been available in private hospitals since its release in February and in public hospitals starting March. The Philippines is second only to Mexico in releasing Dengvaxia for sale and public use.
Doses of the vaccine are given six months apart. Under the SBI program of the DOH, the government will spend a total of Php 3,000 per child to complete the required three doses, for total of Php 3.5 billion for all public school children. The high cost prevented the DOH from purchasing the vaccine in October 2015.
The Philippines was one of the countries involved in the 20-year trial of the vaccine, which was done in five Asian countries and five Latin American countries where dengue is endemic. The vaccine was launched here in the country after all three phases of the trial have been completed, with 3,500 students from Cebu and San Pablo, Laguna participating.
The average direct medical cost of treating dengue in the country from 2008 to 2012 was estimated at $345 million US dollars annually according to a study on the economic cost and burden of dengue in the Philippines published in 2015 in the American Journal of Tropical Medicine and Hygiene.
Vaccinating annually for five years starting in 2016 will result in an estimated 24.2% decrease in dengue cases, according to a study done by the University of the Philippines National Institute of Health.