Dengue is an acute mosquito-borne viral infection that places a significant socioeconomic and disease burden on many tropical and subtropical regions of the world. It is currently recognized as one of the world's emerging infectious diseases. About 50-100 million cases of dengue fever and 500,000 cases of Dengue Hemorrhagic Fever (DHF), resulting in around 24,000 deaths, are reported annually. Over half of the world's population resides in areas potentially at risk for dengue transmission, making dengue one of the most important human viral diseases transmitted by arthropod vectors in terms of morbidity and mortality clinical infectious disease (Jelinik, 2000).
The four dengue viruses originated in monkeys and independently jumped to humans in Africa or Southeast Asia between 100 and 800 years ago. Dengue remained a relatively minor, geographically restricted disease until the middle of the 20th century. The disruption of the second world war-in particular the coincidental transport of Aedes mosquitoes around the world in cargo - are thought to have played a crucial role in the dissemination of the viruses. DHF was first documented only in the 1950's during epidemics in the Philippines and Thailand. It was not until 1981 that large numbers of DHF cases began to appear in the Carribean and Latin America, where highly effective Aedes control programs had been in place until the early 1970's. (CDC, 2015)
Dengue fever and the life - threatening dengue hemorrhagic fever (DHF) often occur in massive epidemics. Dengue spreads rapidly afflicting a great many people during an epidemic causing loss of lives. (Lim, 2001)
WHO declared dengue and dengue hemorrhagic fever to be endemic in the Asian sub-continent. Presently, dengue is endemic in 112 countries of the world.
In 1953, the Philippines became the subject of the epidemic transmission of serious mosquito-borne diseases caused by viral infection. Aside from malaria and classic dengue fever, Philippine Hemorrhagic fever became a notifiable disease in the country in 1958.
The National Epidemiology Center of the Philippines' Department of Health reports a total of 59,943 dengue cases from January 1 to September 6, 2014. This is 59.57% lower compared to the same time period last year (148,279) of the total cases, 10.47% came from Northern Mindanao (Region X), 9.6% from CARAGA (Region XIII), 9.19% from Davao Region (Region 11). Next is from Region IV-A and, Region III, which are 8.93% and 8.01% respectively, to the overall figure. Majority of the infected patients were 5 to 14 years old children (38.91% of the total cases), and more than half were males (52.77%). A total of 242 deaths (CFR 0.40%) were recorded since January 2014, and most of them were children. (WHO, 2015)
In the Philippines, dengue is reported as a leading cause of childhood hospitalizations. By September 2011, the disease had already resulted in 285 deaths of children between 1 and 9 years of age 2. Fatalities for the 1-9 years of age cohort accounted for nearly 60% of deaths due to dengue in 2011. Capeding M.R. Dengue in the Philippines. (Capeding, 2014)
Given this scenario, the aim of my study was to determine the statistical data of incidence rate in Bohol. The researcher is also keen to find out the municipalities affected by dengue fever and its specific incidence rate to determine which has the leading incidence cases of dengue fever in the Province of Bohol.
The researcher also primarily concentrates on the age group distribution to encourage families, private and government agencies such as schools and other institutions to be more equipped with knowledge on how to avoid and somehow help control the spread of this disease.