The World Health Organization has sought to eliminate filariasis, globally, by 2030, a decade later than its original target of 2020. While India’s target year is now 2027, this deadline has been arrived at after several revisions: the National Health Policy had originally set the goalpost for 2015. Filariasis, clearly, has been difficult disease to eradicate.

While pioneering experiments by vector specialists over the years have helped India reduce its disease burden, consistent efforts are needed to eliminate the disease, reports have acknowledged. 

“Filariasis is the common term for a group of diseases caused by parasitic nematodes belonging to the superfamily Filarioidea. Adult worms of these parasites live in the lymphatic system, cutaneous tissues or body cavity of the humans and are transmitted through vectors”, explains a documents from the National Centre for Vector Borne Diseases Control.

Filariasis caused by nematodes that live in the human lymph system is called Lymphatic Filariasis (LF). The burden of lymphatic filariasis is massive in India, with as many as 670 million persons at risk for the disease, according to a report published in the Indian Journal of Medical Research in 2022. 

While the disease has been around for decades in India, there still exist many misconceptions about it, says S. Sabesan, former director of the Indian Council of Medical Research — Vector Control Research Centre, Puducherry.

Kerala’s story with filariasis

Kerala  was instrumental in spotlighting filariasis in India. In 1984-85, a group of filariasis affected persons in Alappuzha formed an association, and its president contested the general election that year, aiming to attract the attention of politicians and bureaucrats. It bore fruit. A Member of Parliament from Kerala S. Krishna Kumar, became the deputy minister in the Union Health Ministry. He called for action against filariasis in Kerala, which set the ball rolling, recalls Dr. Sabesan. 

Kerala’s culture of associations helped to further the project of eliminating filariasis, he says. All associations were amassed under the umbrella of the Filariasis control movement or ‘Filco‘ movement. The project targeted removing floating vegetation where mosquitoes that cause the disease breed. The mosquitoes lay eggs on leaves and the larvae absorb oxygen from the air sacs in the roots of the plants. Understanding the breeding pattern of the mosquitoes helped remove the floating vegetation, which was then placed as manure in coconut groves.

To control mosquitoes the State Health Department also targeted Kerala’s large resource of ponds and water bodies to develop aquaculture, using fish from dams. The fish would feed on the larvae, curtailing mosquito breeding.

Interdepartmental support

Support also came from Kerala’s Agriculture Department which saw the potential of improving livelihoods in rural areas. Shramdhan workers cleaned temple tanks, canals and water bodies, and NABARD pitched in with financial support to remove the plants, and establish aquaculture.

In two years, inland fisheries had been developed. To add value to the removed water vegetation, hemp was cultivated. This improved the quality of fertilisers that coconut groves received. Ultimately, the Health Department roped in the Education Department to raise an army of schoolchildren who could spread awareness to help improve adherence to treatment of the disease. 

The Health Department also used the knowledge of how village residents checked the feet of eligible young women to check if they harboured the disease before offering a marriage proposal. The Department made a young woman with lymphatic oedema, in whose family many women had been rejected owing to the disease, their mascot. The young woman recovered from filariasis after treatment and this boosted people’s confidence. Her story was made into a short film, Yudham (war) and exhibited, giving further fillip to treating the disease. Alongside, the Department trained Filco workers to detect the disease and bring in patients for treatment.

Free clinics were opened to offer treatment. The next step was checking for hidden disease, which involved mass drug administration. Soon, the number of cases fell drastically indicating that the disease was in the elimination stage.

The Kerala Health Department’s approach included collaborating with the Agriculture Department to develop aquaculture, engaging schoolchildren for awareness, and using a recovered patient as a mascot. Mass drug administration and training workers to detect and treat the disease led to a significant reduction in cases, pushing filariasis towards elimination. Picture shows an awareness campaign on filariasis held in Tamil Nadu (Photo taken on August 21, 1987)
PHOTO: THE HINDU ARCHIVES

A win, and a mass strategy

The success of the experiment was shared at the WHO’s meeting in 1996 in Kuala Lampur and the World Health Assembly decided on a strategy of administering a single dose of diethylcarbamazine citrate (DEC).

In India, the annual single dose mass therapy was introduced in 2002, but the nation-wide the scheme did not help in eliminating the disease, for want of follow-up care.

In 2006, the Union Health Ministry introduced the drug Albandazole that can have an effect on adult worms of the parasite. But there was a lack of compliance, even though the drugs were distributed. The Health Ministry found that despite distributing the drug there, was no reduction in the number of cases.

Meanwhile in Kerala another development took place.

The salt story

Through a project, salt-infused with a low dose of the drug DEC was introduced in Kerala. This project was launched with the support of the salt corporation in Thoothukudi in Tamil Nadu. Within a year, the number of filariasis cases fell significantly. The project’s success was expanded in Tamil Nadu’s Kanyakumari district in 2003. 

By 2020, the Indian Council of Medical Research launched DEC salt in Andaman and Nicobar and successfully eliminated another variety of filariasis. This salt therapy could be used as an adjunct therapy across the country Dr. Sabesan has said in the white paper he has published on the subject: Not only is it odourless, but it also doesn’t change the colour of food and is safe for pregnant women and children as well. 

For the success to be sustained it is imperative that we achieve the target of elimination, he says. “Tamil Nadu is doing well. But filariasis is found in Karnataka, Andhra Pradesh, Bihar and Uttar Pradesh as well. There are areas where filariasis is a challenge. If uncontrolled, filariasis will be reintroduced, as the vector is already present in the atmosphere. The low density carriers will build up gradually. So it is necessary to continue surveillance even after elimination is declared. Vector entomologists must focus on the mosquitoes and the vector,” he emphasises.

Telangana State AIDS Control Society (TSACS) presented data on the number of HIV cases detected in Telangana in 2024. The image is used for representative purposes only.
| Photo Credit: RAMAKRISHNA G

As many as 9,415 people in Telangana tested positive for HIV in 2024, according to data presented by the Telangana State AIDS Control Society (TSACS). The figures emerged during a high-level review meeting chaired by Minister for Health C. Damodar Raja Narasimha on Monday.

A total of 19.02 lakh individuals were tested for HIV in the State during the year. Officials informed the Minister that approximately 1.24 lakh people living with HIV were currently receiving free treatment through the network of Antiretroviral Therapy (ART) centres across Telangana.

TSACS officials said that more than 5,000 HIV patients were concentrated in 13 districts, while another 13 districts had between 2,000 to 5,000 patients. The Minister instructed health officials to scale up testing in all districts, especially targeting high-risk groups, and to intensify awareness programmes to curb the spread of the virus.

He stressed the need to regularly assess the performance of NGOs working in collaboration with TSACS. “The State government is committed to the goal of eliminating HIV AIDS by 2030. All our efforts should be directed toward this objective,” he said.

Dementia cases are expected to triple globally, with low- and middle-income countries projected to bear a disproportionate burden. Addressing high blood pressure could be a key strategy in reducing dementia risk | Image used for representational purpose only
| Photo Credit: Getty Images

Addressing high blood pressure could lower one’s risk of developing cognitive impairment by 16 per cent and dementia by 15 per cent over the following four years, according to clinical trial results published in the journal Nature Medicine.

Cognitive decline usually precedes dementia, an ageing-related condition that steadily impairs one’s speech, memory and language.

The phase 3 clinical trial involved nearly 34,000 patients aged over 40 in rural China. People in 163 villages were provided hypertension treatment through medicines and lifestyle changes, while people in other 163 villages continued their usual care.

Researchers, including those at The University of Texas, U.S., found that over a follow-up period of four years, systolic blood pressure fell by 22 mm Hg and diastolic blood pressure by 9.3 mm Hg, among the people treated for hypertension.

Further, at the end of the four-year follow-up, “anti-hypertensive treatment was associated with a 15 per cent reduction in dementia events,” the authors wrote.

Dementia: prevention and management

Dementia cases around the world are expected to triple over the coming decades, with low- and middle-income countries projected to bear a disproportionate burden.

Blood pressure is known to be a risk factor for developing dementia. A study, published in the journal Neurology in January, showed that an aggressive control of blood pressure for over three years can provide sustained benefits in preventing cognitive decline.

Future directions for health research

However, the research team said that few trials have looked at whether treating blood pressure through medicines could impact one’s risk of dementia.

Reacting to the study, Julia Dudley, head of research at Alzheimer’s Research U.K., said, “This large trial of over 33,000 people in rural China provides further evidence that addressing high blood pressure could be one way to reduce dementia risk.” The study is consistent with a Lancet Commission report, released in August 2024, that newly added ‘high cholesterol’ to a list of risk factors for dementia, added Ms. Dudley, not involved with the study.

The list now consists of 14 risk factors, all of which together account for nearly half of the world’s dementia cases. However, “while the results from this trial are reassuring, further studies are needed to understand how other risk factors like genetics interact with factors like high blood pressure to influence dementia risk,” Ms. Dudley said.

The researcher added, “It will also be interesting to see whether interventions trialled in this study can work in other populations across the world.”