Lao PDR becomes second country in 2023 to eliminate ‘lymphatic filariasis’

Context:

As per the information by World Health Organization (WHO), the Lao People’s Democratic Republic has eliminated lymphatic filariasis (LF).

This year, Lao is the second country after Bangladesh for such an announcement.

About the Disease:

It is commonly known as elephantiasis and is a neglected tropical disease.
Infection occurs when filarial parasites are transmitted to humans through mosquitoes.
Infection is usually acquired in childhood causing hidden damage to the lymphatic system.
The painful and profoundly disfiguring visible manifestations of the disease, lymphoedema, elephantiasis and scrotal swelling occur later in life and can lead to permanent disability.
These patients are not only physically disabled, but suffer mental, social and financial losses contributing to stigma and poverty.

Currently, 856 million people in 52 countries are living in areas that require preventive chemotherapy.

Causes and transmission:

Lymphatic filariasis is caused by infection with parasites classified as nematodes (roundworms) of the family Filariodidea.

There are 3 types of these thread-like filarial worms:

Adult worms lodge in the lymphatic vessels and disrupt the normal function of the lymphatic system.
The worms can live for approximately 6–8 years and, during their life time, produce millions of microfilariae (immature larvae) that circulate in the blood.
Mosquitoes are infected with microfilariae by ingesting blood when biting an infected host. Microfilariae mature into infective larvae within the mosquito.
When infected mosquitoes bite people, mature parasite larvae are deposited on the skin from where they can enter the body.
The larvae then migrate to the lymphatic vessels where they develop into adult worms, thus continuing a cycle of transmission.
It is transmitted by different types of mosquitoes for example by the Culex mosquito, widespread across urban and semi-urban areas, Anopheles, mainly found in rural areas, and Aedes, mainly in endemic islands in the Pacific.

WHO response:

To eliminate lymphatic filariasis as a public health problem; in 2000, Global Programme to Eliminate Lymphatic Filariasis (GPELF) was launched.
In 2012, the WHO neglected tropical diseases roadmap reconfirmed the target date for achieving elimination by 2020.
WHO’s strategy is based on 2 key components:
- Stopping the spread of infection through large-scale annual treatment of all eligible people in an area or region where infection is present; and
- Alleviating the suffering caused by lymphatic filariasis through provision of the recommended basic package of care.