Health Medical Pharma

Opinion: Dr K Leelamoni on dengue prevention, surveillance in India

Opinion: Dr K Leelamoni on dengue prevention, surveillance

October 3, 2023: Limna Purushan, 46, works as a domestic helper in my home in Kochi. She has been saving up all her life to build what she says is her “dream home.” 

That was not the sole reason for the worried look on her face when she came to work recently. Her 23-year-old son had developed a fever with headache and severe body aches.

The concern: Was it Dengue, the disease that has displaced the other mosquito-borne disease malaria in the Indian consciousness over the past few decades?

According to the latest report of the National Center for Vector Borne Disease Control of the Government of India, more than 94,198 cases and 91 deaths were reported in the country this year (till September 17).

Kerala topped the list with 9,770 cases and 37 deaths. 

From 4,083 cases and 32 deaths in 2018, the number of cases had almost doubled in the southern state.


Limna’s response to my queries showed the awareness that may have contributed to the highest number of reported cases of dengue, a viral infection caused by the dengue virus (DENV), in Kerala.

 “I will give my son paracetamol (acetaminophen)  tablets and wait for 2-3 days. If the fever doesn’t subside, I will take him to hospital,” she told me. 

I thought she hit the nail right on. 

During these times we need to have the same level of awareness about personal protective measures and how to control the Aedes aegypti mosquito, the vector of the break-bone fever or dengue.

It is interesting to note that till about two decades ago, the most common and dreaded mosquito-borne disease in India was malaria. 

Even in the curriculum of medical schools, dengue and chikungunya were accorded a low priority till the 1990s, and considered to be mainly the headache of African countries. 

Not any longer, as it is obvious now. About half of the world’s population is now at risk of dengue with an estimated 100–400 million infections occurring a year.


Aedes aegypti, are fierce and aggressive “day-biters” that can live indoors for several days. They prefer to remain indoors in the dark corners of rooms, under chairs and other furniture. People sharing the same room or using the same workplace get infected easily.

Whether indoors or outdoors, these mosquitoes prefer fresh, clean water to lay eggs — even a small spoon of water will suffice. 

This takes us to the first key step of prevention. Water containers big or small, especially those kept over window sills, flower pots, and water coolers become egg-laying sites.

Broken bottles and coconut shells found scattered outside are also preferred by the mosquito.

Though normally a self-contained disease, dengue can become fatal in some cases when an already infected person with a specific serotype of the virus gets infected with a different serotype. 

Also at risk are those with comorbidities like diabetes, hypertension, heart disease and chronic kidney disease.

Timely consultation

Other than removing open water containers at home, early confirmation of the disease and timely referral to hospitals, with facilities like blood and platelet transfusion, is critical to prevent a fatal outcome.

In Kerala, for instance, abundant and incessant rain resulting in waterlogging in many areas over the last few years has been pointed out as one of the major factors behind the increase in cases.

It is well known that increased humidity and stagnant water help in mosquito breeding and survival.

Among the other key prevention measures is the participation of the local population in identifying breeding sources. 

The population at risk should also ideally wear long-sleeved clothes and pants to minimise the risk of a bite.


At a higher level, regular monitoring and surveillance for mosquitoes and other vectors should be an integral part of the health system. 

Developing a dedicated workforce consisting of public health experts and epidemiologists will be useful in preventing recurrent seasonal outbreaks. Apart from strengthening hospital facilities for severe cases, constant surveillance should be mounted for emerging new viral strains.

Dengue is found in tropical and sub-tropical climates worldwide, mostly in urban and semi-urban areas. The incidence of dengue has risen globally, with cases reported to the WHO increasing from 505,430 cases in 2000 to 5.2 million in 2019.

Dengue continues to affect Brazil, Colombia, the Cook Islands, Fiji, India, Kenya, Paraguay, Peru, the Philippines, the Reunion Islands and Vietnam as of 2021. The disease is now endemic in more than 100 countries and has spread to the European region.

Back at my home, meanwhile, Limna is keeping her fingers crossed. Hopefully, it’s not dengue, she said. I agreed. Even if it is, her awareness about the disease, I told her, is half the battle won.

(The writer was a former Head of the Department of Community Medicine at the Government Medical College in Kozhikode and Thiruvananthapuram and worked at the Amrita Institute of Medical Sciences in Kochi.)

1 Comment

  • Dr. Ratnakumari October 26, 2023

    Very nice presentation.
    Nice way of prrsenting facts. To start with a real case of fever made tte reading interesting.

Leave a Reply

Your email address will not be published. Required fields are marked *