Amidst concerns over global warming, the World Health Organization (WHO) issued a stark warning earlier this year in July, underscoring the perilous link between rising temperatures and the surge in dengue infections worldwide.
Dr Raman Velayudhan, Head of WHO’s Global Programme on the Control of Neglected Tropical Diseases, revealed that about half of the world’s population is at risk of dengue, and dengue affects approximately 129 countries
WHO further reported that the cases of the disease, which causes fever and muscle pain, represent just a fraction of the total number of global infections since most cases are asymptomatic. It is fatal in less than 1% of people.
The Lancet, in its annual global countdown on the health impacts of climate change, highlighted a concerning trend: the number of months conducive to dengue transmission by Aedes aegypti mosquitoes has risen to 5.6 months per year in India, reflecting a 1.69% annual increase between 1951-1960 and 2012-2021.
As of 26 October 2023, Nagaland recorded a staggering 2,899 confirmed cases of dengue, marking the highest incidence on record. Dr Niesakho Kire, the state program officer of the National Centre for Vector Borne Disease Control, disclosed to PTI that the first dengue case in Nagaland surfaced a mere eight years ago in June 2015.
With cases on a relentless rise and many going unreported due to factors like limited awareness, insufficient testing, and reliance on home remedies, Kire said that the figures could be just the tip of the proverbial iceberg.
“Climatic change is undoubtedly a significant factor. Rising temperatures, erratic rainfall, and urbanization provide fertile ground for Aedes mosquitoes, carriers of the dengue virus, to breed. Dimapur, once a city with moderate temperatures, has now become one of the hotspots. Dengue has seeped into the hilly regions, affecting villages where healthcare facilities are limited,” Kire was quoted by PTI.
Attributing the surge in dengue cases to climatic changes, Kire emphasized that rising temperatures, unpredictable rainfall, and urbanization have created fertile grounds for Aedes mosquitoes to breed. Cities like Dimapur, once characterized by moderate temperatures, have now become hotspots. Dengue has infiltrated hilly regions, affecting villages with limited healthcare facilities.
Kire explained that unpredictable rains, combined with widespread construction and inadequate drainage systems, create stagnant water pockets ideal for mosquito breeding.
As per the PTI report, the transmission of dengue, closely linked to three key environmental factors—rainfall, humidity, and temperature—dictates the geographies in which it spreads, and the transmission rate of the viral infection caused by the dengue virus (DENV), transmitted to humans through the bite of infected mosquitoes. According to WHO, a warmer climate is believed to expedite mosquito multiplication and facilitate the virus’s replication within their bodies.