Are climate change and tuberculosis related?

Populations in developing countries contract tuberculosis more easily

by Lorenzo Ciotti
Are climate change and tuberculosis related?

The classic symptoms of tuberculosis are a chronic cough with blood-streaked sputum, infrequently high fever, night sweats, and weight loss. Infection of other organs causes a wide range of symptoms. Diagnosis is based on radiological examination, commonly a chest X-ray, a tuberculin skin test, blood tests, and microscopic examination and microbiological culture of body fluids.

Treatment is difficult and requires taking multiple antibiotics for a long time. Antibiotic resistance is a growing problem in coping with the disease. Prevention is based on screening and vaccination programs with the Calmette-Guérin bacillus.

Populations in developing countries contract tuberculosis more easily, as they often have a more compromised immune system due to the high rates of AIDS. The distribution of tuberculosis is not uniform throughout the world, about 80% of the resident population in many Asian and African countries test positive for tuberculin, while only 5-10% of the US population is affected.

The study A scoping review on climate change and tuberculosis, published on the International journal of biometeorology, told: "Climate change is a global public health challenge. The changes in climatic factors affect the pattern and burden of tuberculosis, which is a worldwide public health problem affecting low and middle-income countries.

However, the evidence related to the impact of climate change on tuberculosis is few and far between. This study is a scoping review following a five-stage version of Arksey and O'Malley's method. We searched the literature using the keywords and their combination in Google scholar, and PubMed.

Climate change affects tuberculosis through diverse pathways: changes in climatic factors like temperature, humidity, and precipitation influence host response through alterations in vitamin D distribution, ultraviolet radiation, malnutrition, and other risk factors.

The rise in extreme climatic events induces population displacement resulting in a greater number of vulnerable and risk populations of tuberculosis. It creates a conducive environment of tuberculosis transmission and development of active tuberculosis and disrupts tuberculosis diagnosis and treatment services.

Therefore, it stands to reasons that climate change affects tuberculosis, particularly in highly vulnerable countries and areas. However, further studies and novel methodologies are required to address such a complex relationship and better understand the occurrence of tuberculosis attributable to climate change."