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Her abdomen appears bloated and she is always tired. She often gets high fever with chills. Her pale skin is a telltale sign of anemia due to malnutrition and her illness. She has lost at least five kilograms in the past two months. She never feels hungry and hardly eats, not that there is much food anyway. Radha suspects she is suffering from the same disease that killed her father six months ago and is also taking toll of her mother and two younger siblings who have been bed-ridden for more than four months.
Radha is one of the 500,000 patients in the world today suffering from a deadly disease called visceral leishmaniasis or kala azar -- Hindi for black fever. Seen in almost 88 countries over the globe, 90 percent of the cases occur in just six countries -- Bangladesh, Nepal, Sudan, Ethiopia, Brazil and India.
As a medical student, almost two decades ago, I had a misconception that this was a rare disease restricted to some faraway village deep in the forests of Africa. But, alas, this notion, carried by many, is because it is one of the many neglected dangerous diseases in developing nations.
Leishmaniasis is a parasitic disease that spreads through the bite of the female sand fly. These flies flourish in warm, humid places and lay eggs in cow dung, cracks in house walls and the bark of old trees. Once the parasite enters the host blood through the painful sting of the sand fly, it attacks the immune cells, destroying them as it multiplies and spreads all over the body.
Various types of leishmaniasis are seen with a wide range of clinical symptoms. In Africa, it mostly affects the skin (cutaneous) causing big ulcers on exposed parts like the face and arms, leaving behind ugly scars after healing. More disabling is the mucocutaneous form, which affects the nose and throat and mouth cavities and also the surrounding areas, leaving the victims unsightly, resulting in their humiliation and even being cast out of society.
The disease commonly seen in India is kala azar, the visceral form of lesihmaniasis. The high mortality, at 50,000 deaths worldwide per year, is surpassed among parasitic diseases only by malaria.
The name kala azar, coined decades ago in India, refers to the skin discoloration observed in patients. It causes massive enlargement of vital organs like the spleen and liver. The scientist Leishman first observed the organism in smears from the spleen of a patient who died of the fever; hence the name of the disease. Death is certain if a patient fails to get treatment on time.
The reasons for the high death rate due to this disease are many and they are all intertwined. A patient of kala azar may not show signs of a clinical infection for several days. Often, this causes a delayed diagnosis. By this time, the patient also suffers from malnutrition and severe anemia. Occasionally, the disease also causes bleeding. Patients are therefore known to die even before they receive medical aid, as must have happened with Radha's father.
Since immune cells are destroyed, these patients are also susceptible to other infections like diarrheas, pneumonias and tuberculosis. Kala azar coupled with HIV infection is a physician's nightmare, as treating such patients is very complicated.
By the time a patient reaches a doctor, he needs treatment for anemia, malnutrition and the other infections in addition to the primary infection. He has a high likelihood of succumbing to any of these medical conditions.
Before starting treatment, accurate diagnosis of kala azar is an absolute must as the current drugs are quite toxic and also expensive. The surest way is examination of aspirates from the spleen or bone marrow. This can be quite challenging as the public health system in rural India is rather underdeveloped.
Blood antibody tests are quite unreliable. Some screening blood tests have been devised but they are not completely foolproof.
Then there is the problem of a suitable medicine for killing the actual parasite. All the drugs available so far need prolonged treatment, for at least three weeks, need to be injected, are expensive and have several side effects.
There is a high chance that patients might drop out of treatment due to side effects and high costs. This might spell a relapse of the fever or development of drug resistance.
Dr. C.P.Thakur, former health minister of India and an avid surgeon who has spent decades working in the field of kala azar, has established through experience that patients undergoing treatment with these toxic drugs must be strictly monitored for side effects like bleeding so that they can be detected promptly and attended to immediately. This way, the patient's life is saved and the drug can also be changed.
Currently, there is only one drug, miltefosine, that can be taken orally but its treatment course costs between US$100 to US$200, a price beyond the means of the poor patients and the public health service of India.
A U.S. non-profit pharmaceutical company, the Institute for OneWorld Health, founded by Dr. Victoria Hale, is developing a drug that can revolutionize the fight against leishmaniasis. A course of treatment with this drug, paromomycin, is expected to cost just US$10. With generous donations from the Bill and Melinda Gates' Foundation and the joint efforts of the governments of India, Nepal and Bangladesh, this drug should soon be available for use.
Leishmaniasis, a globally neglected disease, has been offering resistance against cure from many angles. But we can hope for some good news now. New drugs are in the pipeline. The vector, the sand fly, can be eliminated as it is still sensitive to DDT, an easily available and inexpensive insecticide. Aggressive research might lead to development of a vaccine that will end the menace for good.
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(Dr. Pradnya Kulkarni is a clinical pathologist from India. She worked as a consultant pathologist in a private laboratory in Pune before moving to Hong Kong with her husband and young daughter. She is also a freelance writer, focusing on medical issues of public concern. ©Copyright Pradnya Kulkarni.)
