Dengue surge in Pakistan amidst the torrential rains: The threat of a potential outbreak
Abstract
With 390 million infections occurring globally and the infection putting half of the world's population at risk, dengue is an illness with potential, life-threatening manifestations such as plasma leakage and fluid retention, severe bleeding, and organ impairment. This disease is already lurking in the various regions of Pakistan, which was recently ravaged by decades’ worst flood. With mosquitoes being its eminent transmission source, it is coherent that a country with massive flooding, accumulation of stagnant water, and lack of adequate drainage systems can lead to a dengue outbreak. Pakistan, a low-middle-income country, is still recuperating from the aftershocks of the pandemic, a recent cholera outbreak, and the massive economic destruction they caused, especially in the healthcare sector. Concerningly, the World Health Organization has already issued a “second catastrophe” warning for Pakistan in the aftermath of the fatal floods which have caused the destruction of hundreds of health facilities while physicians and medical workers on the ground scramble to combat outbreaks of waterborne and other illnesses. If the spread of dengue isn't contained immediately, it will destroy the healthcare systems across the country and result in massive fatalities. To avoid tragic consequences, the government and concerned authorities must devise plans to launch public health programs aimed at boosting knowledge of the disease, its symptoms, transmission, prevention, and control. In this commentary, we discuss the current spike of dengue virus, epidemiology, transmission patterns, and preventative efforts in the aftermath of Pakistan's disastrous floods.
Lately, Pakistan has fallen prey to a catastrophe in the form of unprecedented and torrential rainfalls. The Pakistan Meteorological Department released a report in July 2022 stating that the province of Sindh received a rainfall of 244.9 mm in comparison to its normal rainfall of 60.1 mm, Balochistan witnessed 163.3 mm of rainfall against 29.7 mm, Punjab received 224.3 mm of rainfall compared to 104.1 mm and Khyber Pakhtunkhwa received 138.8 mm as opposed to its typical rainfall of 106.7 mm.1 These record-breaking downpours have led to the emergence of the deadliest flash and urban floods of the decade in Pakistan, impacting 33 million people, leaving over 6.4 million people in urgent need of relief, and claiming more than a thousand lives. WHO has warned the nation of the risk of deadly water-borne diseases like malaria and dengue in the wake of the devastating flooding, and an uptick in dengue cases is already being observed across the country.2
It is an incredibly alarming state of affairs that since July 4th, 2022, which marked the beginning of heavy monsoon rainfalls,1 Pakistan has reported an increase in 932 cases of Dengue virus as documented by the European Center for Disease Control and Prevention.3 Another report claimed that the Primary and Secondary Health Department in Punjab has recorded a total of 2033 cases of Dengue virus.4 Health officials in the southern region of Sindh province have reported 3830 incidences of dengue fever, with at least nine fatalities.5 Together with this, each day in Khyber Pakhtunkhwa, more than 200 people are testing positive for dengue on average thus setting off alarm bells of a potential dengue outbreak.6 Historical data also provides evidence that there was a substantial surge in dengue cases across the country following flooding brought on by the summer monsoon rains in 2009 and 2010, implying that the outbreak was fostered by the heavy downpours.7
The unusually heavy precipitation has made very favorable conditions for the dengue virus. The absence of a functional drainage system has led to a significant accumulation of stagnant water after the flooding. Together with this, retained water in containers, and tires, have been excellent breeding grounds for mosquitoes carrying the pathogen, augmenting dengue cases. Poor sanitary conditions, heaps of garbage everywhere due to improper garbage disposal, and millions of people who lack awareness and supplies have also raised the likelihood of an upsurge in dengue cases, further contributing to the threat of a dengue outbreak.
Dengue carries an estimated prevalence of 390 million infections worldwide, causing 25,000 fatalities annually.8 Approximately 50% of the world's population (3.5 billion) is currently in danger from dengue, drastically increasing the worldwide burden of the disease, with 70% concentrated in Asia alone.9 Ten Southeast Asian nations are home to 1.3 billion of the world's 3.5 billion people exposed to the danger of dengue fever.9 This disease, caused by the dengue virus (DENV) with four distinct serotypes, is a vector-borne disease transmitted to humans by the bite of an infected female mosquito, mainly the Aedes aegypti. The extrinsic incubation period (EIP) of 8–12 days is influenced by the ambient temperatures ranging optimally between 25°C and 28°C, thus indicating that lower temperatures in rainfall can have a major impact on the spread of the virus. If not managed properly, the disease can progress to its potentially fatal complications, Dengue Hemorrhagic Syndrome, which includes severe manifestations such as plasma leaking, fluid accumulation, excessive bleeding, respiratory distress, or organ dysfunction.
The lack of a specific treatment for Dengue virus and no commercially available vaccine for it in Pakistan presage a crisis for the overburdened healthcare of the nation that is in shambles following the recent Cholera outbreak and the Covid-19 pandemic. The decade's worst flood, wrecking approximately 900 healthcare facilities across the country2 and leaving millions of masses deprived of basic medical necessities has made it obligatory for the governing bodies and concerned authorities to promptly release a complete plan of action and adequate funds to restore healthcare system, upgrade sewage infrastructure and ameliorate water sanitation. Strict hygiene regulations must be enforced throughout the country. Public health initiatives aiming at increasing awareness of the disease, its symptoms, transmission, prevention, and control, must be taken to avoid fatal consequences.
Vector control programs (VCPs), aimed at halting the life cycle of the Aedes mosquitoes, subsequently aiding its elimination from breeding environments such as indoor containers, discarded tires, drums, barrels, and tanks, must be constituted. VCPs will help eradicate the spread of other mosquito-borne illnesses as well, such as Malaria, Chikungunya, and the Zika virus. Decreased DENV transmission can be achieved by the promising and proven strategy of introducing Aedes aegypti infected with the virus-blocking bacteria Wolbachia into the environment.10 Moreover, the use of genetically modified male Aedes aegypti that carry the lethal RIDL (Release of Insects with Dominant Lethal) gene, resulting in the transmission of the transgene to embryos and the subsequent death of larvae when they mate with wild-type females, is another effective method for controlling dengue vectors.10
It is the need of the hour that the Government and Non-Governmental Organizations establish free-of-cost medical camps and transport mobile clinics in flood-hit areas to dispense healthcare facilities and dengue testing services. In addition, mosquito repellants, insecticide spray, and insecticide-treated nets must be dispensed for free to protect citizens from the disease. Because dengue is endemic in Pakistan, an early warning system is required to prevent a potential outbreak and a probable epidemic. For accurate case counting and better prevention efforts, public health surveillance techniques must be implemented to assist in evaluating the geographical spread of dengue, thereby aiding in taking early measures and appropriate distribution of resources. Since a shortage of platelets has been reported by the labs, health officials must do their share by organizing blood donation campaigns with adequate screening facilities. Finally, a comprehensive framework is required for the execution of Disaster and Disease Preparedness Programs to avert the major devastation and resultant fatalities occurring due to natural and health crises. However, failure to adopt such preventive measures will result in catastrophic death tolls, exacerbating the already strained healthcare system of Pakistan.
AUTHOR CONTRIBUTIONS
Aqsa Shoaib: Conceptualization, data curation, writing – original draft. Najwa Salim: Conceptualization, data curation, writing – original draft. Summaiyya Waseem: Supervision, visualization, writing – review and editing.
CONFLICT OF INTEREST
The authors declare no conflicts of interest.
Open Research
DATA AVAILABILITY STATEMENT
Data sharing is not applicable to this article as no data sets were generated or analyzed during the current study.
