Eva Sapi Ph.D.
Eva Sapi Ph.D. is an Associate Professor of Biology and Environmental Science at the University of New Haven, where she combines teaching with research, leading graduate students in developing a higher level of understanding of Lyme disease.
In her research, Dr. Sapi investigates the presence of different formations (spirochete, round bodies and biofilm) of Borrelia burgdorferi, the Lyme disease bacteria. She also studies resistance of these different forms to antibiotics and natural agents. She organized three national Lyme disease conferences in the last several years.
Introduction
Lyme disease is caused by the species of bacteria, Borrelia burgdorferi, and is transmitted to humans by a vector ticks, Ixodus scapularis. (1-2) Many investigators, including the University of New Haven Lyme disease research group, focused on identifying novel tick-borne bacteria, viruses and fungal co-infections in ticks or in patients with a tick bite history. (1-2) Despite these efforts and the introduction of novel treatment protocols, there are little improvements in the outcome of some of the Lyme patients.
Can species other than bacteria, virus or fungus be responsible for these chronic problems found in Lyme patients? It has been proposed that certain parasites could also be a factor in Lyme disease. European doctors have already incorporated Ivermectin, an antihelminth drug, into their Lyme disease protocol with surprising success. Ivermectin is well known for its effectiveness against filarial nematode infections and is often used by veterinarians to eradicate parasitic infections. (3)
Can Lyme disease patients have filarial nematode co-infection and can they acquire this infection from ticks? The only evidence reported of filarial worm presence in ticks was from a study by Burgdorferi’ in 1984 where thirty microfilarial worms (species not identified) were found in one adult Ixodis dammini tick in Shelter Island, NY. (4) Black flies have already been identified as vectors of filarial nematodes. (5) Interestingly, ticks can also be used as an in vitro experimental vector system to study the transmission of filarial nematodes and it was shown that the infected nymphal stage could transmit the filarial worms. (6) If filarial nematodes could be a tick-borne co-infection of Lyme disease patients, their eradication would require additional treatments using specific filaricidal drugs, which could explain why standard antibiotic based protocols often fail in some chronic Lyme disease cases. (7)
Preliminary research data on the potential presence of filarial nematodes in ticks from the University of New Haven research group, suggested that Ixodes tick could harbor filarial nematode DNA sequence and these sequences have high similarity to one of the filarial nematode species called Onchocerca (Presented at ILADS conference on October 29th, 2009 and at the University of New Haven Lyme Disease Conference on May 8th 2010.)
Filariasis infects more than one hundred and twenty million men, women, and children throughout the world (8). There are a number of nematode species that use mosquitoes as their vectors, causing different lymphatic filariasis infections. Onchocerca volvulus, for example, is responsible for river blindness.(9) However, it is very possible that the species we have found in deer tick is a novel Onchocerca species due to that there are only being partial similar to known Onchocerca species. A phylogenetic approach is being used now to determine the exact filarial genus and species similarity.
Identification of this potential novel tick-borne pathogen could help to design more specific tests and treatment for patients with a tick bite history and could provide a novel therapeutic target for physicians to explore for those chronically ill Lyme disease patients.
This study is supported by the Turn the Corner Foundation to E.S.
1. Krause, P.J. et al. 1996. Concurrent Lyme disease and Babesiosis: Evidence for increased severity and duration of illness. JAMA; 275: 1657-1660.
2. Adelson, M.E. et al. 2004. Prevalence of Borrelia burgdorferi, Bartonella spp., Babesia microti, and Anaplasma phagocytophila in Ixodes scapularis Ticks Collected in Northern New Jersey. J. Clin. Microbiol; June 1, 2004. 42(6): 2799 – 2801.
3. Mullen, G. & Durden L. 2009. Veterinary Importance. Med. Vet. Entomol; Academic Press. 2nd Ed. 263.
4. Beaver, P.C. and Burgdorferi W. 1984. A microfilaria of exceptional size from the Ixodid tick, Ixodes dammini from Shelter Island New York. J. Parasitol; 70: 963-966.
5. Walsh E. 1983. Sampling simuliid black flies. Pest and Vector Management in the Tropics: 93-99.
6. Olmeda-Garcia A.S. & Rodriguez J.A. 1994. Stage specific development of filarial nematodes in vector ticks, J. Helminthol; 68, 231-235.
7. Stricker, R.B. 2007. Counterpoint: long-term antibiotic therapy improves persistent symptoms associated with Lyme disease. Clin Infect. Dis; 45(2):149-157.
8. Rajan, T.V. 1990. Molecular biology of human lymphatic filariasis. Exp. Parasitol; 70: 500-503.
9.Morales-Hojas, R., Cheke, R.A. & R.J. Post. 2007. A preliminary analysis of the population genetics and molecular phylogenetics of Onchocerca volvulus (Nematoda: Filarioidea) using nuclear ribosomal second internal transcribed spacer sequences. Mem Inst Oswaldo Cruz. Nov; 102(7): 879-882.
NLBF does not necessarily endorse the opinions expressed in this article; and the author of this article does not necessarily endorse NBLF’s points of view.{jcomments on}
