Kala-azar Disease

• Between 2007 and 2022, the number of Kala-azar cases in India fell by 98.7%, from 44,533 to 834, with 632 endemic blocks (99.8%) in Bihar, Uttar Pradesh, Jharkhand, and West Bengal receiving eradication status (less than one case per 10,000).
• Littipara in the Jharkhand district of Pakur is the sole remaining endemic block (1.23 cases per 10,000 population).

About:

• It is a slow-moving indigenous disease caused by a protozoan parasite from the genus Leishmania.
• Kala-azar, also known as leishmaniases, is one of the most deadly neglected tropical diseases (NTDs) that is endemic in 76 countries and threatens roughly 200 million people.

Forms:

• There are three types of leishmaniasis: visceral (also known as kala-azar, the most severe form of the disease), cutaneous (the most common, affecting the skin), and mucocutaneous.
• It is a fatal parasitic disease caused by the protozoa parasite Leishmania that primarily affects humans in Africa, Asia, and Latin America.
  • If left untreated, the condition can be fatal.

Global and National Status:

• According to the World Health Organization (WHO), Kala-azar is the world's second-deadliest parasitic disease, with approximately 89% of global cases reported from eight countries as of November 2022: Brazil, Eritrea, Ethiopia, India, Kenya, Somalia, South Sudan, and Sudan.
• India accounts for approximately 11.5% of all Kala-azar cases reported globally.
• Over 90% of kala-azar cases in India are reported from Bihar and Jharkhand, while Uttar Pradesh and West Bengal have met their block-level elimination targets.
• It is transmitted to humans through the bite of an infected female phlebotomine sandfly.
• Fever, weight loss, anemia, and liver and spleen enlargement are all symptoms.
• Kala-azar prevention entails actions to eliminate sandfly breeding areas and to protect humans from sandfly bites.
• This can be accomplished by utilizing pesticides, bed nets, and repellents, as well as improving living conditions and providing access to clean water and sanitation.
• In locations where the disease is endemic, the WHO also recommends Mass Drug Administration (MDA).

Treatment:

• Kala-azar is treated with medications such as sodium stibogluconate and meglumine antimoniate.

Impacts:

• Malnutrition, population dislocation, poor housing, a weakened immune system, and a lack of financial resources are all related with the disease.
• Environmental changes such as deforestation, dam construction, irrigation systems, and urbanisation have also been related to leishmaniasis.

Control and prevention:

• Leishmaniasis prevention and control necessitate a variety of intervention measures.
• It is a treatable and curable condition that "needs an immunocompetent system because treatments will not remove the parasite from the body, increasing the likelihood of relapse" if immunosuppression occurs.
• Effective disease surveillance is critical for monitoring and responding quickly during epidemics and circumstances with high case fatality rates under treatment.

Initiatives that are related:

• Global: The World Health Organization's New Roadmap for 2021-2030: By 2030, a group of 20 diseases known as neglected tropical diseases must be prevented, controlled, eliminated, or eradicated.
• The WHO has also developed the Global Programme for the Elimination of Lymphatic Filariasis (GPELF), which seeks to eliminate MDA-caused lymphatic filariasis, onchocerciasis, and Kala-azar.
• The GPELF aim of eliminating these diseases globally by 2020, set in 2000, was not met. Despite difficulties caused by Covid-19, WHO will ramp up efforts to meet this aim by 2030.

Indian Government effort:

• To attain its goal of removing kala-azar from India by 2023, the central government has taken many efforts, including building pucca dwellings through the PM-AWAS yojana, rural electrification, testing, treatment, periodic high-level review, and award distribution.

National Kala-azar Elimination Program

• The National Health Policy 2002 set the objective of eliminating Kala-azar in India by 2010, which was later changed to 2015.
• India signed a Memorandum of Understanding (MoU) with Bangladesh and Nepal to eradicate Kala-azar from the South-East Asia region (SEAR).
• Currently, all programmatic activities are carried out through the National Vector Borne Disease Control Programme (NVBDCP), which serves as an umbrella program and is part of the National Health Mission (NHM).

Kala-azar Disease

Recently, a team of researchers from the National Centre for Cell Science (NCCS), Pune have found new biomolecules to fight drug resistance in Kala-azar (visceral leishmaniasis). NCCS is an autonomous organisation under the Department of Biotechnology, Government of India. It was established to facilitate cell biology research in the country.

Leishmaniasis

• It is a neglected tropical disease affecting almost 100 countries including India.
  Neglected tropical diseases are a diverse group of communicable diseases that prevail in tropical and subtropical conditions in 149 countries.
• It is caused by a parasite called Leishmania, which is transmitted through the bite of sand flies.

There are three types of leishmaniasis:

• • Visceral leishmaniasis affects multiple organs and is the most serious form of the disease.
  • Cutaneous leishmaniasis causes skin sores and is the most common form.
  • Mucocutaneous leishmaniasis causes skin and mucosal lesions.

Visceral leishmaniasis, which is commonly known as Kala-azar in India, is fatal in over 95% of the cases, if left untreated.

Resistance to Drug: The only drug available against leishmaniasis, miltefosine, is rapidly losing its effectiveness because of emerging resistance to this drug due to a decrease in its accumulation inside the parasite.

Responsible Proteins: A protein called ‘P4ATPase-CDC50’, is responsible for the intake of the drug by the parasite, and another protein, called ‘P-glycoprotein’, is responsible for throwing this drug out from within the parasite’s body.

A decrease in the activity of the former protein, and an increase in the activity of the latter results in less accumulation of miltefosine inside the parasite’s body, thus causing it to become resistant to the drug.

While exploring ways to tackle miltefosine resistance, the researchers worked with one of the species of Leishmania that causes infection, called Leishmania major.

They tried to manipulate these transporter proteins in the species in a manner that would result in increased uptake of the drug and a decrease in its being thrown out of the parasite’s body.

They used computational methods to design small molecules, called peptides, that could very specifically interact with the transporter proteins of Leishmania major alone, and not interfere with human proteins in any way.

A peptide is a short chain of amino acids. Amino acids are organic compounds that combine to form proteins.

Also read: https://www.aspireias.com/daily-news-analysis-current-affairs/The-Orphan-Drug-Act-Rare-diseases