Cases of dengue fever, which is primarily spread through mosquito bites, usually increase in number during the rainy season.
Dengue is a female Aedes mosquito-borne disease caused by a dengue virus infection. Dengue fever symptoms will begin three to 14 days after the mosquito bite and last for two to seven days.
The Aedes mosquito is easily identifiable by the distinctive black and white stripes on its body. It prefers to breed in stagnant water easily found at homes in uncovered vessels such as flower pots, clogged drains, plastic bottles and discarded tyres.
Scientists have said that hotter and wetter weather brought on by climate change has created ideal conditions for female mosquitoes to lay their eggs.
In addition to there being more mosquitoes, the rapid urbanisation in many Asian nations means that susceptible populations are living in closer contact with disease-carrying insects.
The symptoms include sudden and persistent fever, muscle ache and the lack of energy. The infection with the dengue virus can also sometimes cause more severe symptoms including bleeding and death, known as Dengue Haemorrhagic Fever (DHF).
Four types of serotype dengue virus have been identified (DEN1, 2, 3 and 4). A person infected with one of the serotypes of the dengue virus and subsequently infected by another serotype increases their risk of getting DHF.
Dengue fever is not contagious but if transmitted, it has no specific treatment. Treatment is more focussed on supportive treatment to relieve symptoms of infection as well as close monitoring in hospital, if needed.
For each case of mosquito-borne disease reported, the Ministry of Health (MoH) in Brunei Darussalam implements measures such as contact tracing to examine people closest to the case and ensure that no one else has symptoms of dengue fever.
Tests are performed on any close contacts found to have symptoms; entomological surveillance is done to examine the entomology in the vicinity of the residence and areas frequently visited by cases to determine the type of vector that may be in the area; and vector control activities are carried out through the use of pesticides to destroy adult mosquitoes and larvae.
Insect monitoring and control is also done routinely, especially in areas that have been identified as hot spot breeding grounds and case clusters.
The ministry has also said that pesticide spraying is only a temporary alternative, and for more effective long-term control, maintaining a clean environment and a place free of becoming a potential breeding hotspot is more crucial.
The public can also take these steps to control mosquitoes inside and outside their home: install screens on windows and door; repair holes in screens; use air conditioning when available; sleep under a mosquito bed net if air conditioned or screened rooms are not available or if sleeping outdoors; wear protective clothing, and use insect repellents; keep the area around homes free from containers that collect water, and, once a week, empty and scrub, turn over, cover, or throw out these items.
The MoH shared in a statement that 43 infected cases and one disease-related death were recorded as of July 25, 2020. The number of cases shows a slight decrease compared to 2019 where 69 cases were reported during the same period, added the ministry.
Dengue cases have increased dramatically worldwide, increasing 30-fold in the past 50 years. There are an estimated 100-400 million infections each year, and about half of the world’s population is now at risk, according to the World Health Organization (WHO).
Neighbouring countries have also been battling the dengue fever since early this year, at a time when state resources have been spent on curbing the COVID-19 outbreak.
It was recently reported that dengue cases in Johor Bahru, Malaysia increased by 6.2 per cent to 7,707 between January 1 and September 12 this year compared with 8,200 cases for the same period last year. State Health Department Director Dr Aman Rabu said that 32 deaths from dengue have been recorded this year compared with 21 within the same period, last year.