Leprosy

Leprosy (Hansen’s Disease), is a chronic infectious disease that primarily affects the peripheral nerves, skin, upper respiratory tract, eyes, and nasal mucosa. The disease is caused by a bacillus (rod-shaped) bacterium known as Mycobacterium leprae (M. leprae).

What is Leprosy?

Leprosy is a chronic infection caused by the bacillus Mycobacterium leprae.

Leprosy Causes

Leprosy Diagnosis and Classification

Leprosy Prevention and Vaccination

Leprosy Research

Forms of Leprosy

Signs and Symptoms of Leprosy

Leprosy Stigma

History of Leprosy

Notable Cases of Leprosy

Leprosy Epidemiology

Leprosy Complications

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Genetics and Susceptibility to Leprosy

Leprosy Treatment

Latest Leprosy News and Research

Scientists trace leprosy’s roots in South America back 4,000 years

Researchers have recovered and sequenced Mycobacterium lepromatosis genomes from 4,000-year-old human remains in Chile, providing the first molecular evidence of ancient leprosy in the Americas. The findings reveal the deep evolutionary roots and complex spread of Hansen’s disease long before European contact.

1 Jul 2025

Ancient DNA sheds light on the origins of leprosy in the Americas

Hansen's Disease, more commonly known as leprosy, is a chronic disease that can lead to physical impairment. Today it exists in over 100 countries, and while the infection is treatable, access to treatment varies widely with socioeconomic conditions.

30 Jun 2025

Understanding antibiotic resistance mechanisms in Mycobacterium species

Announcing a new article publication for BIO Integration journal. Tuberculosis (TB) is caused by Mycobacterium tuberculosis (M.tb) complex (MTBC), which includes M.tb as one of the causative bacteria.

3 Jun 2025

Genetic analysis shows leprosy was endemic in pre-colonial America

Long considered a disease brought to the Americas by European colonizers, leprosy may actually have a much older history on the American continent.

29 May 2025

Syphilis family traced to Pre-Columbian Americas

In spring 1495, the Italian campaign of Charles VIII of France was interrupted by an intense outbreak of an apparently unknown illness – a disease of high mortality that quickly engulfed the whole of Europe and left its survivors with life changing impairments to their bodies and minds.

18 Dec 2024

Study suggests mosquitoes as potential vectors for Buruli ulcers in Australia

Researchers find strong evidence suggesting mosquitoes may transmit Mycobacterium ulcerans, the bacteria causing Buruli ulcers, but caution that further study is needed.

15 Aug 2024

The case of the armadillo: Is it spreading leprosy in Florida?

In an open-air barn at the edge of the University of Florida, veterinarian Juan Campos Krauer examines a dead armadillo's footpads and ears for signs of infection.

24 May 2024

WHO's new SkinNTD app proves effective in training healthcare workers for neglected tropical diseases

The SkinNTD app, developed by the WHO, shows promise in training frontline healthcare workers in low- and middle-income countries to diagnose and manage neglected tropical diseases. Early evaluations in Ghana and Kenya indicate the app is user-friendly, effective, and valuable for remote areas.

20 May 2024

Experts advocate three-pronged approach to identifying missing tuberculosis cases

In the journey towards a world free of Tuberculosis (TB), the crucial first step begins with identifying individuals affected by the disease.

25 Mar 2024

AHRI partners with BGI Genomics to boost its genomics and precision medicine capabilities

On October 13, 2023, in Addis Ababa, Armauer Hansen Research Institute (AHRI) and BGI Genomics signed a Memorandum of Understanding to enhance the Institute's genomics and precision medicine capabilities.

21 Nov 2023

Uniting Against Antimicrobial Resistance: An Interview with the World Health Organization

An interview with Kitty van Weezenbeek, Director of Surveillance, Prevention and Control of AMR for the World Health Organistion (WHO) AMR division.

20 Nov 2023

Doctors advocate fresh efforts to combat Chagas disease, a silent killer

When Maira Gutiérrez was diagnosed with Chagas disease in 1997, neither she nor her primary care physician had even heard of the malady. She discovered her illness only by chance, after participating in a Red Cross blood drive organized by her employer, Universal Studios.

22 Aug 2023

Researchers find new way to target leprosy infection

Leprosy has existed since at least Biblical times, yet scientists still don't know exactly how Mycobacterium leprae causes the disease's symptoms.

12 Jul 2023

Study identifies the predictors of post-coronavirus disease 2019 (COVID-19) syndrome symptoms

Study identifies the predictors of post-coronavirus disease 2019 (COVID-19) syndrome symptoms.

30 Jun 2023

Aggressive lung pathogen may not be prone to person-to-person transmission

A little-known bacterium - a distant cousin of the microbes that cause tuberculosis and leprosy - is emerging as a public health threat capable of causing severe lung infections among vulnerable populations, those with compromised immunity or reduced lung function.

30 May 2023