Kalaa zar in Bangladesh
The parasitic disease kala-azar (visceral leishmaniasis, VL) was first described in 1824 in Jessore district, Bengal (now Bangladesh). Epidemic peaks were recorded in Bengal in the 1820s, 1860s, 1920s, and 1940s. After achieving good control of the disease during the intensive vector control efforts for malaria in the 1950s-1960s, Bangladesh experienced a VL resurgence that has lasted to the present. Surveillance data show an increasing trend in incidence since 1995.” (Bern C, Chowdhury R.)
My mother is from Jessore, so I have visited the villages near Jessore several times to meet my relatives and for paying respect to my grandparents’ graves. As a child, I always wondered why the children in the village ate so much!? Most of the children there had swollen abdomen. Recently I came to know about this disease that pretty much answered my untold question. While doing a course (Medical Diagnostic) I came to know about leishmaniasis and started looking into it. I am sure most of us have come across patients with this disease known as Visceral Leishmaniasis. Visceral Leishmaniasis is a type of Leishmaniasis that causes swollen abdomen and is very common in Bangladesh especially among the poor. To my surprise, I have met many people who misunderstood VL as worm disease!
Leishmaniasis is a disease that is transmitted by sandflies (mainly female phlebotomine) and caused by obligate intracellular protozoa, genus Leishmania. About 21 of 30 species cause human infection. These include the L. donovani, L. mexicana L. tropica; L. major; L. aethiopica; etc.
There are three main forms of the disease:
Visceral leishmaniasis, VL (kala-azar) can be deadly if left untreated. Symptoms include- irregular bouts of fever, weight loss, enlargement of the spleen and liver, and anemia. An estimated 200 000 to 400 000 new cases of VL take place globally each year. Over 90% of new cases occur in six countries: Bangladesh, Brazil, Ethiopia, India, South Sudan, and Sudan. Enlargement of the spleen and liver causes the swelling of the abdomen.
Cutaneous leishmaniasis (CL) is the most common kind and causes ulcers on unprotected portions of the body, leavinlifelongng marks and stern disability. Over two-third of CL new cases occur in six countries: Afghanistan, Algeria, Brazil, Colombia, Iran (Islamic Republic of) and the Syrian Arab Republic. An estimated 0.7 million to 1.3 million new cases occur worldwide annually.
Mucocutaneous leishmaniasis- causes damage to the mucous membranes of the nose, mouth and throat. Around 90% of muco-cutaneous leishmaniasis cases take place in Bolivia, Brazil and Peru.
Major risk factors
Poverty escalates the risk of leshmaniasis. The leading reasons are deprived housing and domestic sanitary conditions that help the proliferation of sand-fly breeding and resting sites, as well as their access to humans.
Diets lacking protein-energy, iron, vitamin A and zinc increase the chances of kala-azar. Leishmaniasis is climate-sensitive, and strongly affected by changes in rainfall, temperature and humidity. Drought, famine and flood resulting from climate change may lead to immense shift and migration of people in areas with transmission of leishmaniasis, and poor nutrition could compromise their immunity.
Though there are many types of Leishmania, the different species are morphologically indistinguishable, but they can be differentiated by isoenzyme analysis, monoclonal antibodies or antigen based immunochromatographic test (ICT).
The first step to a treatment is to make sure the diagnosis is correct. Factors like the type of leishmaniasis, the Leishmania species that caused it, the potential severity of the case and the patient's underlying health has to be considered.
The skin sores of cutaneous leishmaniasis usually heal without treatment. But this can take months or even years, and the sores can leave ugly scars. Another apprehension applies to some types of the parasite found in parts of Latin America: certain types might spread from the skin and cause sores in the mucous membranes of the nose (most common location), mouth, or throat (mucosal leishmaniasis). Mucosal leishmaniasis is not usually noticed before the original sores healed. Ensuring adequate treatment of the cutaneous infection is the best approach to avert mucosal leishmaniasis. Severe cases of visceral leishmaniasis are usually fatal if not treated.
Prevention and control
Prevention and control of leishmaniasisnecessitates an amalgamation ofthe intervention policiess because the disease spreads through a complex biological system involving the human host, parasite,Sandflyy vector and in some causes an animal reservoir. Early diagnosis decreases the prevalence of the disease and stops disabilities and death. Now, there are extremely effective and safe anti-leishmanial medicines, particularly for VL and access to these medicines is improving. Awareness of the disease is vital since it allows victims and the relatives of the victims to take measures. Vector control is very important for the regulation of this disease. Insecticides, aerosols and mosquito nets should be used to prevent sandflies from transmitting the disease. An effective disease surveillance is mandatory. Timely detection and treatment helps diminish spreading of the disease and monitor the transmission and burden of disease.
Bangladesh is flooded with diseases. Poor hygiene and overpopulation acts as an aid for the transmission of many diseases. Raising awareness among ourselves may help prevent these. Leishmaniasis, chiefly VL is a severe ailment, yet a number of people perceive it to pass away like a common infection. People having the symptoms must visit hospitals for diagnosis. Benjamin Franklin once said ‘An ounce of prevention is worth a pound of cure.’
1. (n.d.). Retrieved August 21, 2014, from www.who.int/leishmaniasis/resources/BANGLADESH.pdf
2. Reducing Visceral Leishmaniasis by Insecticide Impregnation of Bed-Nets, Bangladesh. (2013, July). Retrieved August 21, 2014, from Centers for Disease Control and Prevention: http://wwwnc.cdc.gov/eid/article/19/7/12-0932_article
3. Leishmaniasis. (2014, April 17). Retrieved August 21, 2014, from MedicineNet.com: http://www.medicinenet.com/leishmaniasis/article.htm
4. Leishmaniasis . (2014, January). Retrieved August 21, 2014, from World Health Organization: http://www.who.int/leishmaniasis/en/
5. C, B., & C. R. (2014). The epidemiology of visceral leishmaniasis in Bangladesh: prospects for improved control.
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