Communities of practice
Filariasis: new drugs and new opportunities for lymphatic filariasis and onchocerciasis
16 Feb 2009
Source: Current Opinion in Infectious Diseases (see original article)
Citation: Hoerauf A (2008). Curr Opin Infect Dis; 21(6):673-681.
2008 Wolters Kluwer Health | Lippincott Williams & Wilkins
Treatment of onchocerciasis and lymphatic filariasis has been largely focused on drugs that act against the microfilarial stages of the parasites responsible for these debilitating conditions. For two decades diethylcarbamazine, ivermectin and albendazole have been used in mass drug administration (MDA) programmes that have achieved a high level of success. However, an alternative approach is to use the antibiotic doxycycline to target the Wolbachia bacteria that are endosymbionts of the parasites and have been shown to be essential for their fertility and survival.
In a review article in Current Opinion in Infectious Diseases Professor Achim Hoerauf points out that, in comparison with currently used regimens, the newer treatment has shown superior activity against the parasites. When a doctor is treating a single patient for disease symptoms then doxycycline seems to be the appropriate for individual drug administration (IDA). Professor Hoerauf says that IDA may offer a new, complementary opportunity for antifilarial drug delivery in developing endemic countries.
The article discusses the use of the ‘classical’ microfilaricidal drugs and reviews the progress that has been made. This is considerable but elimination of lymphatic filariasis and onchocerciasis as public health problems in areas of high endemicity will be more difficult, using these drugs, than was at one time anticipated. There are also concerns resulting from the appearance of resistance to ivermectin in onchocerciasis programmes. In lymphatic filariasis it is now considered that – since that the disease-inducing stage of the worm is the adult residing in the lymphatics – an agent with adulticidal activity will be required to improve the effectiveness of treatment.
While the drugs used in MDA are excellent tools for transmission control, for the best possible treatment of individual patients, IDA with doxycycline is an exciting new option. Much of the article is given over to discussing the evidence supporting this position. Recommendations for treatment using doxycycline are also provided. Although successful treatment requires 4–6 weeks, it has limited side effects and does not lead to the adverse reactions of drugs that kill adult filariae too rapidly, which results in pain, abscess formation or both.
The article also outlines the priorities for future research. Professor Hoerauf believes that in the battle against filarial diseases, “the exploitation of antibiotics is only at its beginning”.
Note: This article is published in a journal which is not open access. To see the full article a subscription to Current Opinion in Infectious Diseases is therefore required. In some developing countries, readers who are based in institutions may be able to access it through the HINARI programme.
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