Malaria Epidemic in Subic, Zambales, Philippines

Resurgence of Malaria in Subic, Zambales, Philippines is happening fueled by economic boom. Yearly outbreaks has been a regular occurrence in the last three years.Each year bigger than the previous. Outbreaks is fed by continuous movement of a significant number of migrant workers brought about by economic activities in the area.

Subic is a former American naval base. The naval base was returned to the Philippines immediately after the eruption of Mount Pinatubo.It was converted to a free port zone and incentives were given to attract foreign investors and provide job opportunities to the country. Several investors locate into the free port area and these attracted workers not only from the province of Zambales but also from other provinces of Luzon. One of the investor is a ship building company. Building ship is a huge investment and a huge task. It requires earth movement to house a ship building facility and it also need a huge manpower complement. Mountains have to be leveled wherein the assembly area will be built as well as to provide accommodation to its workers. Roads has to be built to provide access. Workers has to be recruited to provide the hands for the construction of all the facilities. Workers has to be in great number to implement the project on time. These activities provide human host is feeding the life cycle of malaria by providing susceptible hosts.

Zambales is a malaria endemic province as well Bataan, its neighbor province. Malaria incidence on Zambales is low previously but occasionally outbreaks occur. Zambales is a mountainous province and indigenous people, the Aetas, is present in the area. Malaria vector is also present in the area.

Malaria epidemic in Subic has been occurring three years in a row. Malaria parasite and its mosquito vector is already in the area long before the economic boom. Movement of workers into the area contributed to the increase in the number of malaria cases owing to several factors. Migrant workers has no immunity since most of them came from non-endemic areas, they are not aware that the malaria exist in the area, and they are not aware that they get malaria from mosquito bite. The sheer number of workers going into Subic every quarter is a management dilemma. About 15,000 to 17,000 new workers arrived for the site construction as well as base workers for ship building. They come from as far as northern Luzon to as far as Bicol and other Islands of the Philippines. Movement of workers and its sheer number make health system inadequate. Local Health authorities cannot cope with the demand.

Health authorities of Subic has been doing its part. They are providing diagnosis and treatment, vector control and health education. They provided net in cooperation with the National Department of Health and the Global Fund through the Tropical Disease Foundation. The interventions made were not perfect. It is not adequate to start with, they cannot cope with the number of workers and its turn over. They are limited in providing vector control. Nets distributed are taken along by the workers once their work contract is through. Another set of workers come in to replace those that finished their work contract not knowing of the danger they face. A new set of unprotected and unaware highly vulnerable workers come in. The health authorities are also limited in information dissemination. They cannot put billboards that will warn the workers since the area is a tourist destination and authorities fear they will drive away tourist. The country as a whole will also be affected in the long run. Workers may reintroduce malaria into their home province.

The local health authorities need to double or quadruple their efforts. They have to increase their diagnostic and treatment facility by increasing the number of microscopist and ensure the availability of medicines all the time. The National Health Office can augment microscopist initially. Vector control may not be adequate or effective because the housing condition is not conducive for indoor residual spraying. Net distribution is not sustainable because of the frequent turnover of workers. The best option is to go to the people. Inform the workers and the ommunity that they need to use mosquito net and prevent malaria themselves. This can be done only thorugh simple poster using a recycled 8x11 bond paper with the message "Iwasan ang malaria Magkulambo" and post it in every door of the house, along the road, in the vehicles and in any area visible to the workers but not to the tourist. This needs replacement every two months. This needs a bold decision since people will be encourage to use the net though it will not be provided. It is putting their health on their own hands. Human nature dictates that if there is danger they will be reacting to it. In the case of Subic malaria, promoting the net use without providing one is a test on how human react to the threat. Monitoring the sale of nets in the public market is good indicator that people are responding. It is always a preconceived idea on part of health providers that people are not capable of buying nets on their own. In times of need through proper guidance of health authorities people will protect themselves. Those who cannot really afford to buy nets are the ones that can be assisted by the health authorities for provision of free nets. This is placing health into the hands of the people. The health authorities' role then is to maximize the use and availability of the diagnostic and treatment facility and guide the people what to do.

Local Health authorities cannot do it alone. They need the cooperation and assistance of all agencies operating in Subic both government and non-government, local and international. Information is power. Forewarned is forearmed. Inform the people. Good Luck Subic!!!

Vector Control and Malaria Elimination

Vector control against malaria consist mainly of Insecticide Treated Nets (ITN) or Indoor Residual House Spraying (IRS). Both of them are effective as long as they are used properly. The current practice is to apply vector control one to two months before the peak season. The purpose of application before the peak season is to taper the incidence of malaria and prevent the seasonal peaks. This very effective in averting the occurrence of the peak but this will only lead to control or reduction of cases and not elimination. This only reduces cases but not necessarily the transmission.
Malaria elimination requires vector control as soon as transmission in a community is identified. It must be done any time of the year in order to prevent the transfer of the parasite to other people which will become another source of parasite to perpetuate the cycle. The most important point is to identify the area or community where there is active or ongoing transmission at the moment. All the control measures then must be applied at the same time in order to eliminate the sources of parasite in all of its location in the community. To reiterate, they are in the mosquito vector, in humans with symptoms of malaria, in asymptomatic malaria carriers, in human with malaria at the pre-patent and incubation period and lastly in the human with hypnozoites in their liver. Failure to address anyone of each location will perpetuate the species and keep the malaria cycle go on and on and on.