Possible dengue outbreak and some thoughts
DENGUE, a viral infection mainly transmitted through Aedes aegypti and Aedes albopictus, has now become a major public health threat to Bangladesh. Dengue infection usually occurs in the monsoon and post-monsoon time, from June to September, but an ‘epidemiological shift’ appears to have occurred in 2019 with more infection before the monsoon. The dengue outbreak that took place in 2019 caused cases of 101,354 infection and 164 death, as official records show. Pre-monsoon dengue infection is reportedly likely this year too.
The first record of a case of probable dengue, referred to as ‘water poison’ associated with flying insects, is found during the Jin dynasty (265–420) in China, but the first recorded dengue outbreak happened in Asia, Africa and North America almost simultaneously in the 1780s, soon after the identification and naming of the disease. In Bangladesh, dengue fever was officially reported for the first time in 2000 that left 93 dead although it also appears that Bangladesh first experienced an undocumented dengue outbreak in 1964. After 2004, the number of deaths decreased, but drastically increased in 2018. The 2019 outbreak broke all earlier records in Bangladesh.
Directorate General of Health Services statistics show at least 271 dengue hospital admission in the past three months. Moreover, a number of surveys, carried out in the capital by the health services directorate general and a team of researchers of Jahangirnagar University, identified an alarming presence of Aedes mosquito larvae in areas under the Dhaka South City Corporation jurisdiction. Dengue virus is found in at least 44 wards, with higher intensity of Aedes in seven wards in the survey done in 98 out of 129 wards.
Even though the pre-monsoon survey does not indicate the presence of Aedes as very risky, the rainy season that is favourable to the breeding of Aedes may make a massive dengue outbreak in many areas. There is, of course, dangerous abundance of almost all risk sources such as open water bodies, drains and containers not only in Dhaka but also in other areas. As a result, a possible spread of aedes larvae bearing four types of dengue viruses such as DENV-1, DENV-2, DENV-3 and DENV-4 remains high during the rainy season.
Because of the ongoing COVID-19 threat, which has impacted the entire health system, an outbreak of dengue, sooner or amidst the threats of the COVID-19 outbreak, can have a devastating impact. Double viral threats can ominously result in a denial of health services, spread of coronacvirus infection and a rising death toll, more expenditure by the government and so on. In fact, hospitals and clinics are not much responsive to other health complications fearing a possible transmission of the coronavirus that has already infected about 6,000 people and, meanwhile, many patients with other health complications have been denied treatments.
Under such possibilities, a well-planned preventive response is crucial. The authorities concerned, however, repeatedly claim having a full preparation this time with sufficient insecticides and mosquito repellents. Indeed, city authorities which insufficiently and sporadically started spraying of insecticides to destroy the sources of Aedes mosquitoes have almost stopped doing so with the onset of the COVID-19 outbreak. The government authorities concerned need to take lessons from the past year’s mistakes, which brought distressing consequences, and step up the current meagre efforts to prevent a potentially massive dengue outbreak.
The government’s preventive efforts need to focus on all urban and rural areas, especially areas vulnerable to a possible dengue outbreak. Given that dengue is more prevalent in cities, city corporations must be active in taking early prevention measures. Effective steps to destroy the sources that can turn into favourable breeding grounds for Aedes are urgent. Widespread awareness campaigns can be of great help, too. The government also needs to ensure that hospitals and clinics treat dengue patients even if coronavirus infection continues to rise or remain as it is now.
The 2019 dengue outbreak made people aware of sources of dengue virus carrying Aedes aegypti and Aedes albopictus, which spread zika and chikungunya viruses too, and the transmission of dengue virus although a large number of people usually are reluctant to follow the health and cleanliness protocols. However, people should be more cautious and aware in order to stave off any repeat of the dengue outbreak.
Lastly, lack of a strong national committee resulted in ineffectually managed response in 2019. But this time, a national steering committee on the prevention of dengue outbreak is going to be formed with representation from various ministries and departments under the local government and rural development ministry to lead and monitor related activities. This is a good step but it is also expected that the committee is formed at the earliest and it needs to strictly lead and monitor all prevention efforts in the capital an in other areas.
Amir Mohammad Sayem writes opinion pieces on social issues, politics, environmental issues, international relations and current affairs.
