The World Health Organization has warned of possible dengue outbreak in Kathmandu Valley.

Two health experts from the UN health agency, who visited the Capital two weeks ago, said that eggs, larva and pupa of Aedes aegypti and Aedes albopictus mosquito, which transmit the dengue virus, were found in huge numbers in various places of the Valley.

“The WHO officials visited some hospitals, academies and public places, where they found eggs, larva and pupa of dengue-spreading mosquitoes,” Dr Bibek Kumar Lal, director at the Epidemiology and Disease Control Division, told the Post on Sunday. “We are at high risk of dengue spread, as the vector is already present in Kathmandu Valley which offers a very suitable environment for the mosquitoes to survive.”

The two experts from WHO’s South-East Asia Regional Office in Delhi and Thailand were called by the WHO’s country office in Nepal at the request of the Ministry of Health and Population.

Several studies carried out in the past had also found the presence of dengue-carrying mosquitoes in significant numbers in the Valley.

Local cases of dengue transmission were also reported in the Valley—at least 18 cases last year in the Banasthali-Sanobharyang area. The division had in the past also alerted local health units of the Valley in Kathmandu, Bhaktapur and Lalitpur to be prepared against a possible dengue outbreak and take precautionary measures.

The team of experts has also cautioned about the trend to hoarding drinking water in the Valley, which gives the dengue spreading mosquitoes a perfect breeding ground.

Dengue-transmitting mosquitoes breed in clean water and bite people in daylight.

Due to an acute drinking water crisis, people in the Valley collect water in various types of containers and keep until they are used. Uncovered water tanks and discarded plastic cups and bottles could become a breeding ground for dengue-carrying mosquitoes.

The experts had also visited Dharan Sub-metropolitan City of Sunsari, where over 3,000 people have been infected this year with dengue virus, and pointed out the underlying causes of dengue spread—the trend of hoarding water, discarded water bottles and plastic cups and garbage piles.

“They stressed the need to raise awareness among people about protecting them from dengue virus and continue the search and destroy drive,” said Ghanshyam Pokhrel, a senior public health administrator at the division. “They asked us not to limit the search and destroy drive to rallies, placards and banners.”

Dengue is a mosquito-borne viral disease, which is transmitted by the female Aedes aegypti and Aedes albopictus mosquitoes. The same vector also transmits chikungunya, yellow fever, and Zika virus, according to the World Health Organization.

According to doctors, mild to high fever, severe muscle pain, rashes, severe headache, and pain in eyes are some of the symptoms of dengue.

The UN health agency says there is no specific treatment for severe dengue, but early detection and access to proper medical care can lower the fatality rate.

According to the division, as many as 3,425 people have been infected with dengue virus in the fiscal year 2018-019—the highest number of infections in 15 years. Among them, 3,152 were from Province 1, with 3,025 cases reported from Sunsari district alone.

According to the data provided by the division, 2,111 people were infected in 2016-017; 1,527 in 2015-016; 811 in 2017-018; 301 in 2013-014 and 134 were infected in 2014-015.

Health experts have warned that the number of dengue cases could increase this year, as the infection has continued and the post-monsoon season is yet to start. There is generally a rise in dengue cases during the post-monsoon season.

Dr Sushilnath Pyakurel, director general at the Department of Health Services, blamed the failure of health agencies to act in a coordinated manner for the spread of dengue.

“I have to accept that we have been unable to contain the spread of the deadly disease due to lack of coordination among various agencies,” said Dr Pyakurel, “Multi-sectoral efforts are needed to contain further spread of dengue fever.”