Dengue is an arthropod-borne viral infection caused by the dengue virus (DENV-1, DENV-2, DENV-3, and DENV-4). It is one of the most rapidly spreading infectious diseases in the world’s tropical regions, transmitted by mosquitoes of the genus Aedes. According to WHO, dengue is now endemic in more than 100 countries all across the globe1.
Female mosquitos, Aedes aegypti, take a blood meal from an infected person. The virus from the blood meal replicates inside the mosquito, reaches its salivary glands, and infects the healthy population2. Aedes aegypti breeds in old tires, laundry tanks, roof guttering, discarded tin cans, and plastic containers3,4. After the person has been infected; they remain asymptomatic during the incubation period of 5–7 days. Symptoms usually arise 3–14 days after the intrinsic incubation period has been completed5. It causes a high-grade fever (40 °C/104 °F) and other symptoms such as muscle and joint pain, headache, retro-orbital pain, vomiting, and rash. Most people recover after receiving symptomatic treatment. Only a fraction of people progresses to the critical stage, resulting in severe abdominal pain, internal bleeding, shock, and even death6. In recent times, the number of dengue cases has been increasing rapidly and has now become a major threat to health care systems worldwide. According to WHO, ~390 million people worldwide suffer from dengue every year, out of which 96 million present with clinically severe symptoms1.
Pakistan has reported multiple dengue outbreaks, such as in 2005, 2010, 2017, 2019, and 2020. In 2021 alone, 48,906 lab-confirmed cases and 183 deaths were reported. Punjab was the most infected province, with 24,146 cases and 127 deaths. Khyber Pakhtunkhwa was second, followed by Sindh, ICT, Baluchistan, Gilgit Baltistan, and Azad Jammu Kashmir (AJK)7. Pakistan is currently witnessing a dengue outbreak with a rapid rise in the number of cases amid devastating floods in the country. According to Health Department, a total of 14,738 dengue virus cases had been reported so far during the current year in different hospitals in Punjab with 292 cases reported alone on Sunday, October 30th8. In October, a total of 8223 cases surfaced all over Sindh out of them 5738 have been reported in Karachi. According to the health department, 18,377 dengue cases surfaced throughout the province from January 1 to October 27, 20229. The provincial health department on Thursday, October 27th reported that 340 more people were diagnosed with dengue in the last 24 hours in Khyber Pakhtunkhwa. The number of active cases in the province currently stands at 1544 and the total number of cases so far this year has reached 17,88310.
Recent catastrophic floods in Pakistan, triggered by torrential rain, have swept away hundreds of homes, claiming thousands of lives, affecting the country with drought, and causing a devastating blow to infrastructure. Pakistan has suffered the damage of about $10 billion with 33 million people affected11. The flood crisis has challenged the country’s enfeebled resource-restrained health care and already poor sanitation. It has put the country at high risk of water-borne diseases witnessing a hefty rise in malaria, cholera, dengue, diarrhea, life-threatening dehydration, and dermatological fungal infections. UNICEF has warned seriously about more child deaths due to water-borne diseases spreading rapidly12. A total number of deaths from diseases since July 1, 2022, has risen to 318, and 426 new dengue-positive cases were reported lately on September 15th. Meanwhile, 148,589 cases of malaria have been reported in Sindh since the floods13. WHO has warned Pakistan that these outbreaks are deemed to show adverse effects shortly, particularly in camps where stagnant water provides favorable conditions for pathogens to grow. Water-borne and vector-borne diseases will spread quickly due to extreme weather conditions. Contact with contaminated water contributes to the leading cause of water-borne diseases.
The threat of the dengue virus has increased multifold in densely populated cities that accommodate large numbers of homeless persons from different parts of the country. Inadequate sanitation, especially in rural areas inhabited by low-income groups with poorly effective mosquito control measures, will serve as breeding foci for dengue-causing mosquitoes.
Knowledge about the steps to prevent the spread of infection prevention plays a vital role in response to the outbreak. Medical experts have shed light on the dengue virus ringing bells around the corner, and hospitals around the country are packed to the brim with dengue cases. Travelers are more vulnerable to acquiring and spreading dengue than the locals, causing a widespread increase in infection14.
It is a massive task for the country to work on the rehabilitation of affected people in catastrophic flooding conditions. Considering the devastation caused by flooding, it is high time to learn how to curb the after-effects of the disaster faced by people, particularly dengue. Access to fresh water should be ensured as it will limit the spread of water-borne diseases. Establishing a dengue task force is the need of the hour for earlier detection of the virus. Access to affordable testing services should be provided to keep a close track of the number of infected people and adequate health care facilities to counter the disease. Vector Control Activities should be practiced by educating the population about routine hygienic practices, covering storage containers, using insect repellant spray and coils, and wearing clothes that keep skin minimally exposed to mosquitos.
To conclude, Pakistan needs to make a comprehensive plan to eliminate dengue outbreaks effectively. Thus concerted efforts should be made on personal and state levels to counter the menace of this public health problem. But dengue will always pose a significant threat to human health, especially in resource-limited countries.
Sources of funding
H.I., L.T., F.M., W.R., and J.A.: conception of the study, drafting of the work, final approval, and agreeing to the accuracy of the work.
Conflicts of interest disclosure
The authors declare that they have no financial conflict of interest with regard to the content of this report.
Research registration unique identifying number (UIN)
Hamza Irfan, Laiba Tanvir, Farheen Malik, Warisha Rafique, Jawad Ahmed.
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