Dengue outbreak: where do we stand?
An outbreak is a sudden occurrence of something unwelcome, such as disease. Dengue is a viral infection transmitted by the bite of an infected mosquito. Dengue fever is marked by an onset of sudden high fever, severe headache, pain behind the eyes, and pain in muscles and joints. Some may also have a rash and varying degree of bleeding from various parts of the body including nose, mouth and gums or skin bruising.
Symptomatic illness can vary from dengue fever to the more serious dengue haemorrhagic fever. Dengue haemorrhagic fever is a more severe form, seen only in a small proportion of those infected. Dengue shock syndrome is a dangerous complication of dengue infection and is associated with high mortality. Severe dengue occurs as a result of secondary infection with a different virus serotype.
Dengue and other mosquito-borne diseases like malaria, Zika virus, chikungunya, yellow fever, among others spread mostly during the monsoon and post-monsoon seasons.
People facing any of the symptoms must rush to a doctor and get the necessary tests done and follow what they are prescribed by the doctor. One should also take adequate rest and increase the intake of liquid. Always keep dengue infected patients covered with mosquito net to prevent spread. Use of mosquito net to protect uninfected persons, if possible, in the daytime.
Rapid and unplanned urbanisation, living conditions for the urban poor and lack of sanitation are all contributing to a surge in numbers of people catching vector-borne diseases. Various awareness drives and campaigns must be carried out on different platforms and health systems are being strengthened to deal with the rising numbers of dengue patients. This year, the dengue fever outbreak may become alarming in Bangladesh where there is panic all over due to COVID-19. While the dengue season generally peaks from May, the density of mosquitos in the capital has increased manifold compared to last year when the country witnessed the worst dengue outbreak in history.
The primary preventative measure to reduce dengue infections is the control of mosquito populations. The transmission of dengue requires mosquitoes as vectors. One practical and recommended environmental management strategy is to eliminate unnecessary container habitats that collect water such as plastic jars, bottles, cans, tires, and buckets in which mosquito can lay their eggs. When container habitats are removed and water storage containers are covered to prevent mosquitoes from getting inside them, mosquitoes have fewer opportunities to lay eggs and cannot develop through their life stages.
Source reduction can be effective when performed regularly, especially when members of a community are mobilised and educated about vector control. Environmental management initiatives can also include major changes in a community, such as installing water systems with direct connections to residences and replacing wells and other water storage containers, which can be mosquito breeding habitats. Smaller-scale environmental changes can also be effective. For example, mosquito populations can be reduced when all members of a community clear blocked gutters and street drains and keep their yards free of containers with standing water.
In Bangladesh, last year's dengue outbreak was unprecedented. But we have to understand that there is no alternative but to raise awareness in destroying the breeding grounds for mosquitoes to bring the dengue menace to an end.
Climate change and changing patterns of rainfall, humidity is leading to longer breeding spells for the mosquitoes and diminishing disease incubation time. This is leading dengue epidemics to become much more unpredictable in terms of when and where they occur, and their scale, overwhelming our already COVID-19 burdened health system.
The writer is a gerontologist and a public health specialist. E-mail: email@example.com