30 January – World Neglected Tropical Diseases Day
More than one billion people worldwide are at risk of illness, disfigurement, disability, and even death from neglected tropical diseases (NTDs). Especially in the poorest regions of the world where access to clean water, sanitary facilities and health care is restricted for many people, viruses, bacteria, parasites, fungi or even poisonous snakes have an easy game. The consequences are serious diseases such as river blindness or sleeping sickness, dengue fever, leprosy, or the effects of snakebites. Since these diseases rarely endanger people in industrialised countries or travellers, they are often neglected in terms of funding for research and therapies.
Africa is one of the regions where neglected tropical diseases occur as “widespread diseases”. “They are often among the most common causes of disease in the affected countries,” says the deputy coordinator of the DZIF research area Malaria and Neglected Tropical Diseases, Prof. Achim Hörauf from University Hospital Bonn.
Promising active agents in clinical testing
One example is river blindness (onchocerciasis), an infection of the cornea caused by the offspring of filariae. The infection leads to vision loss in one in twenty patients and blindness in one in a hundred. The risk of infection with these filariae is particularly high along rivers where their vector, the blackfly, can be found. About 21 million people are infected. DZIF scientists led by Prof. Hörauf, Prof. Marc Hübner, Dr Kenneth Pfarr and Dr Andrea Schiefer at the University Hospital Bonn have developed the antibiotic corallopyronin A. It acts against certain bacteria that live in the filariae and are vital for them. Currently still in the preclinical phase with transition to a human phase 1 trial planned for 2024, corallopyronin A is one of the most promising drug candidates for the treatment of tropical filarial infections. The scientists in Bonn also have a number of other drug candidates for the treatment of worm diseases in the pipeline.
Together with Prof. Michael Ramharter, coordinator of the DZIF research area Malaria and Neglected Tropical Diseases and Head of the Department of Clinical Research at the Bernhard Nocht Institute for Tropical Medicine (BNITM), Prof. Hörauf, Prof. Hübner and Dr Klarmann-Schulz are also conducting clinical trials on the treatment of the worm disease loiasis in the Central African region. With the help of the studies, the scientists want to find out whether certain broad-spectrum anti-worm drugs are able to successfully eliminate the so-called African eyeworm, Loa loa. Scientists at the Centre de Recherches Médicales de Lambaréné (CERMEL) in Gabon—an African Partner Institution of the DZIF—are also significantly involved in the studies.
For an exciting insight into the worm disease loiasis, read the article "Once the worm is in" (in German) in the SYNERGIE magazine of the German Centers for Health Research.
Schistosomiasis—global second only to malaria
Schistosomiasis is the second most common parasitic tropical disease worldwide after malaria. The pathogen is a fluke that feeds on human blood. Infection occurs through contact with freshwater, where the larvae develop in freshwater snails. The worms can severely damage various organs and, among other things, limit fertility in women. DZIF scientists led by Dr Daniela Fusco at the BNITM in Hamburg are working to further develop diagnostics and, above all, rapid tests for schistosomiasis. The goal is to determine the prevalence of schistosomiasis in Madagascar more precisely and to treat those affected in a more targeted way. Another DZIF-supported study led by Prof. Ramharter and Dr. Johannes Mischlinger of BNITM in collaboration with CERMEL and Prof. Kremsner of the University Hospital Tübingen is investigating a new strategy of preventive therapy for schistosomiasis in school children in high-endemic areas of Gabon.
DZIF scientists at the Institute for Tropical Medicine, Travel Medicine and Human Parasitology of the University Hospital Tübingen are also working intensively on schistosomiasis and filariae. Schistosomiasis is often accompanied by co-infection with other parasites. "In Africa, especially in the sub-Saharan region, people are often infected by two or three parasite species at the same time," explains Dr Carsten Köhler. In DZIF-supported projects, he and his colleagues Dr Meral Esen, Dr Andrea Kreidenweiss and Dr Jana Held are improving and developing diagnostics and therapy for new infections with juvenile schistosomes—an early developmental stage of the worms—and researching chronic infections with innovative immunological methods.
An ominous interplay
Led by PD Dr Inge Kroidl, scientists in the Division of Infectious Diseases and Tropical Medicine of the LMU University Hospital Munich are investigating the interaction between certain worm diseases and HIV infections. In a cohort study in Tanzania, they found out that an infection with the worm Wuchereria bancrofti increases the risk for an infection with HIV by a factor of two to three. The first positive results have already been obtained on the question of whether treatment of the worm also reduces the risk of HIV infection. Co-infection of the Schistosoma species S. haematobium with HIV or the human papillomavirus (HPV) is another focus of research in a joint project with Prof. Clarissa Prazeres da Costa of the Technical University of Munich. The fact that schistosomiasis can also cause genital changes is still little known to both doctors and patients. Moreover, the diagnostics available to date are rather unreliable. "This problem is to be specifically investigated and improved in the DZIF central research theme "Neglected tropical diseases", explain Prof. Prazeres da Costa and PD Dr Kroidl.
For inquiries about neglected tropical diseases, feel free to contact the DZIF experts denoted above and below. Please email all inquiries and cc them to presse@dzif.de.
DZIF experts:
Prof. Dr. Marc Hübner
University Hospital Bonn
E-Mail
Dr. Daniela Fusco
Bernhard Nocht Institute for Tropical Medicine, Hamburg
E-Mail
Dr. Dr. Carsten Köhler
University Hospital Tübingen
E-Mail
Dr. Meral Esen
University Hospital Tübingen
E-Mail
Dr. Andrea Kreidenweiss
University Hospital Tübingen
E-Mail
Dr. Jana Held
University Hospital Tübingen
E-Mail
PD Dr. Inge Kroidl
LMU University Hospital Munich
E-Mail
Prof. Dr. Clarissa Prazeres da Costa
Technical University of Munich
E-Mail
