It attracts little attention, but every year 50000 people die of kala azar (visceral leishmaniasis), a tropical disease transmitted by sand flies. There are few effective drugs to treat kala azar, and most are unaffordable to people in developing countries.
The disease is neglected by pharmaceutical companies yet affects half a million people every year, mainly in Asia and Africa.
The symptoms are a prolonged fever, an enlarged spleen and weight loss. Without treatment, patients die within months.
Since January 2010, we have been running a kala azar treatment centre in the state of Al-Gedaref in eastern Sudan, 500 kilometres east of the capital, Khartoum. MSF staff use a rapid diagnostic test, taking a drop of blood from the patient’s finger, to check for the illness.
We talked to Dagemlidet Worku, the Ethiopian doctor in charge of the project, about treating the disease. He has previously tackled kala azar in Kenya and Uganda.
MSF Dr. Daggy Worku with a young patient at the MSF Swiss kala azar clinic in Kacheliba, northwestern Kenya © Susan Sandars/MSF
What struck you most when you arrived in eastern Sudan?
“In Kenya, I was used to treating 60 or 70 cases a month. In Al-Gedaref, when we started work at the kala azar treatment centre in Tabarak Allah, we were receiving as many as 150 patients a day in January.Some had travelled up to 130 kilometres to get treatment.
"Today we have an average of 100 patients a month.
“There wasn’t enough space in the building and we were forced to treat people under a tree. The patients were then transferred to temporary shelters, and eventually we built a new ward. I was very surprised by this influx; my Sudanese colleagues weren’t quite so surprised.
“Al-Gedaref is one of the regions in Sudan hardest hit by kala azar. In some villages, all the inhabitants are infected. Eighty-five percent of the cases recorded in northern Sudan come from this state.”
Why is this region so severely affected?
“Al-Gedaref’s climate and topography are particularly favourable for the sand flies that transmit kala azar. These insects take refuge in the cracks that form in the ground after the rainy season and in tree trunks.
“As there are 10 health centres specialising in the treatment of kala azar, patients come from other states to be treated.
“Al-Gedaref is also the place where the progress of the disease is most closely monitored. I’m sure that if the same attention were paid to it elsewhere in north Sudan, the percentage of cases recorded in Al-Gedaref would fall.”
Despite these efforts, the disease isn’t yet under control?
“A lot more financial resources are needed. Al-Gedaref has become an important region for research on kala azar, but not enough research is being focused on improving diagnosis and treatment.
“For example, sodium stibogluconate (SSG), the first-line drug against kala azar, was developed in the 1930s.
“Also, the treatment centre managed by MSF is the only one that uses a rapid screening test. This test is very easy to use, as it simply involves taking a drop of blood from the patient’s finger.
“Kala azar is a strange disease. Some of the symptoms vary, depending on whether the sufferer is in Kenya or Sudan.
“The effectiveness of the screening tests and treatment also differs depending on the country. For example, in India, patients can be cured by a single session of intravenous liposomal amphotericine B, the second-line drug. In Africa, single doses don’t work.
“Without operational research, all these differences remain a mystery.”
Why are children more affected by kala azar?
“Because they have lower immunity to fight the infection. Not everyone who comes into contact with kala azar develops the disease. What’s more, patients who have been treated before are immune to it.
“It’s no coincidence that HIV/AIDS sufferers are more vulnerable, because their immune systems are already weakened.”
Abdelrazig, who is 15 months old, is being held by his mother, Rafaa, while the nurse looks for a vein in which to inject the liposomal amphotericine B infusion. © Mohamed Nur Eldin
How can this disease be eradicated?
“As a medical organisation, MSF is trying to treat as many sufferers as possible. In 2010, we screened some 7000 people and treated around 1200 cases. The cure rate has reached 96 percent and, once cured, people are immune to the disease. That’s the best way of reducing the stock of infection.
“To eradicate kala azar, living conditions need to be improved. In Sudan, as elsewhere, kala azar hits the poorest. It attacks those weakened by malnutrition.
"As the dried mud walls of the houses are an ideal refuge for the sand flies that carry kala azar, putting up plastic sheeting inside would be a simple measure; but the communities concerned often can’t even afford to do that.
“There is doubt about the effectiveness of mosquito nets in preventing kala azar. As with all parasitic diseases, MSF simply encourages people to protect themselves by keeping their skin covered.”
Since 1988, MSF has treated more than 80000 patients with kala azar, principally in East African countries including Sudan, Ethiopia, Kenya, Somalia and Uganda.
MSF has validated and introduced rapid diagnostic tests (rK39 antigen-based dipsticks), that can be used in remote settings, providing much greater access to treatment for kala azar sufferers. If treated on time, 95 percent of patients make a full recovery.