What is black fever or 'kala-azar'? Symptoms, treatment, prevention and all you need to know about this disease

Eleven districts of Bengal have reported at least 65 cases of black fever or 'kala-azar' in the last couple of weeks, a senior official of the health department said, citing results of a state-administered surveillance.

The districts where maximum number of cases was registered include Darjeeling, Malda, Uttar Dinajpur, Dakshin Dinajpur and Kalimpong.

The districts of Birbhum, Bankura, Purulia, Murshidabad have also reported a few cases of black fever, mainly transmitted by bites of sandflies infected with the parasite 'leishmania donovani'.

What is Black Fever or Kala-Azar?

Visceral leishmaniasis (VL), also known as kala-azar is a fatal disease, if left untreated in over 95 per cent of cases. According to World Health Organisation (WHO), it is characterised by irregular bouts of fever, weight loss, enlargement of the spleen and liver, and anaemia. Most cases of kala-azar occur in Brazil, East Africa and in India.

It remains one of the top parasitic diseases with outbreak and mortality potential. The disease affects some of the poorest people and is associated with malnutrition, population displacement, poor housing, a weak immune system and lack of financial resources.

Diagnosis and treatment for Kala-azar:

In visceral leishmaniasis, diagnosis is made by combining clinical signs with parasitological, or serological tests (such as rapid diagnostic tests).

The treatment of leishmaniasis depends on several factors including type of disease, concomitant pathologies, parasite species and geographic location. Leishmaniasis is a treatable and curable disease, which requires an immunocompetent system because medicines will not get rid of the parasite from the body, thus the risk of relapse if immunosuppression occurs. All patients diagnosed as with visceral leishmaniasis require prompt and complete treatment.

How to prevent Kala-Azar or Black Fever?

According to the WHO, the diagnosis of visceral leishmaniasis is established by combining clinical indicators with parasitological or serological investigations (such fast diagnostic tests).

Leishmaniasis therapy is influenced by a number of variables, such as the disease kind, coexisting diseases, parasite species, and geographic location.

Leishmaniasis is a treatable and curable condition that needs an immune system that is functioning normally since medications will not completely eradicate the parasite from the body, increasing the chance of relapse if immunosuppression takes place.

Vector control helps to reduce or interrupt transmission of disease by decreasing the number of sandflies. Control methods include insecticide spray, use of insecticide–treated nets, environmental management and personal protection.

Published on: Saturday, July 16, 2022, 06:29 PM IST