How Climate Change Hampers Fight Against Vector-Borne Diseases in South Asia

© AP Photo / Manish SwarupIn this Tuesday, Sept. 27, 2016 photo, a giant sized billboard on dengue awareness, a mosquito-borne viral ailments, stands by the side of a road in Gurgaon, on the outskirts of New Delhi, India.
In this Tuesday, Sept. 27, 2016 photo, a giant sized billboard on dengue awareness, a mosquito-borne viral ailments, stands by the side of a road in Gurgaon, on the outskirts of New Delhi, India. - Sputnik International, 1920, 13.10.2022
Subscribe
Monsoon rains create a perfect environment for mosquito breeding, leading to an exponential spike in their population. The surge in water-borne diseases comes alongside several South Asian states now grappling to contain the spread of dengue and malaria, both tropical diseases spread by mosquitoes.
According to the World Health Organization (WHO), around 70 percent of dengue — a viral disease transmitted by the Aedes Aegypti mosquito — is reported in Asia's tropical and subtropical areas.
The disease occurs in two forms: either with flu-like symptoms including fever and vomiting, or as dengue hemorrhagic fever (DHF) —where platelets in the body fall, which is a more deadly form.
With dengue cases mounting in the Indian capital, the Delhi government directed all hospitals to reserve at least 10-15 percent of beds for dengue patients on Tuesday. The move came after 321 cases of dengue were reported in the first five days of October, bringing the total number of cases reported this season to 1,258.
The spike hasn't been limited to Delhi: over the last decade, West Bengal reported more than 20,000 cases, prompting the state health department to restrict hospital staff holiday time.

According to the WHO, the surge in vector-borne diseases, including malaria, will be the second disaster in Pakistan after unprecedented rainfall claimed the lives of more than 1,700 people. The country may record 2.7 million cases by January 2023.

Children sleep on a cot covered with a mosquito net in their temporary shelter after their homes for inundated with floodwaters in New Delhi, India, Thursday, Sept. 29, 2022. - Sputnik International, 1920, 11.10.2022
Pakistan Decides to Purchase 6.2 million Mosquito Nets From India
Bangladesh, too, has seen an outbreak of dengue, with at almost 22,000 cases and about 70 deaths recorded this year.
Talking to Sputnik, Deputy Director for the Centre for Environmental Health Poornima Prabhakaran said: "If we compare previous years' data, not just numbers of infected patients are increasing, but the disease is spreading geographically too."

"Ten years ago, the southern part of India did not use to report dengue or malaria cases, but now the diseases are spread to that part too," Prabhakaran said, opining that the mosquito-borne disease could become a serious threat on the future.

Explaining the connection between vector-borne disease and dengue, Dr. Monalisa Sahu, an infectious diseases consultant at the Yashoda Hospital in Hyderabad, told Sputnik that studies show that temperature plays a crucial role in the ecology of mosquito virus.
"Ambient temperature has been associated with a faster rate of viral replication within the vector and a shorter extrinsic incubation period resulting in faster disease transmission," she stated. At the same time, "variability in rainfall influences habitat availability for Ae. aegypti, and Ae. albopictus (both a breed of mosquito found in South East Asia) larvae and pupae."
Dr. Sahu explained that temperature and rainfall act as the chief regulator of evaporation, thereby also affecting the availability of water habitats. "Indirectly, rainfall, temperature, and humidity influence and promote or impede the growth of vector populations."

"That's the major reason we're seeing a rise in cases across South East Asia," she added, given that different parts of the region, especially India and Pakistan, recorded dramatic heatwaves and unprecedented spells of rainfall this year.

Dhavan also underlined that mosquito populations are rising in countries where climate change has become a top issue on the agenda.
Pakistan is the most drastic example, where a health emergency has been declared due to stagnant flood water, which provide the perfect home for mosquitoes to lay eggs. As per Pakistani officials, it may take up to three to six months for the floodwaters to fully recede.
Meanwhile, rains are expected to pick up again in Pakistan this month.
Prabhakaran argued that "let's not just think that people with lower social and economic status are vulnerable": younger, older people, people with chronic diseases - everyone's health is directly or indirectly affected.
Speaking about how regions should prepare, Prabhakaran said: "There is a need for decentralized planning as both malaria and dengue exist in particular geographies."

Moreover, people often forget that mosquitoes' favorite places to breed are dark, humid and unventilated areas. That's why housing plays a very important role in climate change, Prabhakaran explained.

"Individuals on their own can only take steps to [prevent infection] by small steps. Civic authorities need to take effective and regular steps — like checking on standing stagnant water during the rainy season, fogging, customized health adaptation plans, moreover, primary healthcare need to be aware," she said.
Municipal workers fumigate a densely populated area in New Delhi, India, Wednesday, Oct. 27, 2021. - Sputnik International, 1920, 05.10.2022
Asian Dengue Outbreak: No Panic, But Systematic Testing Needed, Doctor Says
Nevertheless, there have been some examples in India which raise hopes of beating the disease.
In the tribal state Odisha, the number of cases of people suffering from Malaria reduced by 89% when test kits were given to healthcare workers (since 2015) who did door-to-door testing in villages. It also helped villagers to become aware of the disease.
In Tamil Nadu, the government availed dengue tests at primary health centers, improving the testing rate and preventing the disease at an early stage.
Newsfeed
0
To participate in the discussion
log in or register
loader
Chats
Заголовок открываемого материала