IN its continued effort to eradicate lymphatic filariasis, Guyana has embarked on an ambitious two-year Mass Drug Administration (MDA) campaign under the National Lymphatic Filariasis Elimination Programme.
Launched in July 2024, the initiative is spearheaded by the Ministry of Health in collaboration with the Pan American Health Organization and the World Health Organization (PAHO/WHO). With a targeted approach, this campaign is focused on eliminating and preventing the spread of the disease, bringing Guyana closer to achieving elimination status by 2030.

Lymphatic filariasis, commonly known as filaria, is a mosquito-borne parasitic disease that can lead to severe disability. The disease is transmitted through the bite of an infected Culex mosquito, which thrives in urban and semi-urban areas. When the mosquito bites an infected person, it ingests microfilariae—tiny parasitic worms present in the blood. These parasites mature within the mosquito, becoming infectious larvae that are passed on to new hosts through subsequent bites.
Although filaria can be contracted in childhood, its most debilitating symptoms—swelling of the arms, legs, breasts, and scrotum—often manifest later in life, leading to long-term physical impairment and social stigma. The disease affects over 120 million people globally, spanning regions in Asia, Africa, the Western Pacific, the Caribbean, and South America.

HISTORICAL PERSPECTIVE
Guyana’s battle against lymphatic filariasis has spanned decades. In 2003, a Ministry of Health assessment found a 9.3 percent positivity rate for filaria nationwide. This alarming discovery prompted a series of interventions, beginning with the introduction of Diethylcarbamazine (DEC) salt—a fortified table salt that was widely distributed to households.

“We put salt in our food, and salt was one of the things that was being used in a broad way across the country,” recalled Minister of Health, Dr. Frank Anthony. “They had maybe one or two importers, and they had to comply by adding DEC to the salt that was being distributed.”
The DEC salt, once consumed, worked by killing microfilariae organisms in the body. However, an unexpected chemical reaction caused the salt to turn blue when heated, leading to widespread rejection by the public. This setback forced health authorities to pivot to distributing anti-filaria tablets.
Between 2016 and 2018, the Ministry distributed a combination of DEC and albendazole tablets, commonly known in Guyana as “worm tablets.” While these drugs were effective, the World Health Organization later introduced an enhanced approach—the triple drug therapy which includes ivermectin alongside DEC and albendazole.

TRIPLE DRUG THERAPY
PAHO/WHO research has shown that the triple drug combination significantly reduces microfilariae in the blood for a longer period compared to the previous double-drug treatment. More importantly, it accelerates the elimination process, requiring only two annual rounds to interrupt transmission, compared to the five-year cycle needed for the previous method. Although mild and temporary side effects may occur, the treatment is generally regarded as safe and effective.
This year, as part of the ongoing MDA campaign, the triple drug therapy is being distributed across the remaining endemic regions—Region Three and Region Four. These two regions are the last in Guyana requiring mass treatment, signalling that the country is in the final stretch of achieving elimination status.

Aiming for Elimination by 2030 Dr. Annastacia Sampson, National Filaria Coordinator at the Ministry of Health’s Vector Control Services, emphasised the significance of this final push.
“We’re looking to have that elimination status by 2030. So we have up until then to put everything in place in order to get that done,” she stated. “And given that we only have two more regions to continue with for MDA, we can now shift our focus in equipping those facilities in other regions.”
Beyond drug distribution, the Ministry continues to promote mosquito control measures to further accelerate disease elimination. These include vector control strategies such as mosquito net distribution, environmental sanitation, and public awareness campaigns.
With only two regions left to complete the MDA campaign, Guyana stands on the verge of a historic public health achievement. If successful, the elimination of lymphatic filariasis will mark a significant victory for the nation, ensuring that future generations are free from the burden of this debilitating disease.