Substantial health threat: Never-before-seen tick-borne disease

Commentary: A study from researchers from China and the University of Maryland has discovered a new tick-borne infection. Dr Stephen Dumler, MD, helped identify the new bacterial species, called Anaplasma capra. “The symptoms of A capra infection include fever, headache, and tiredness, dizziness and muscle aches (similar to other Anaplasma infections)….Because no one knew the bacteria existed, no one has looked for it, and it is not clear how widespread it is. The researchers successfully treated the infection with antibiotics, particularly doxycycline.”

The discovery of this new bacteria is part of a growing international problem with ticks and emerging infections. In the last decade, we have seen an increase in the number of new bacterial infections in ticks, such as Borrelia miyamotoi, and other relapsing fever bacteria, like Borrelia bissettii. Borrelia miyamotoi was discovered in up to 4% of New England residents (NEJM), and B. bissettii was recently implicated as a human pathogen in Mendocino County, California (Girard YA, Fedorova N, Lane RS. Genetic diversity of Borrelia burgdorferi and detection of B. bissettii-like DNA in serum of north-coastal California residents. J Clin Microbiol. 2011;49:945–54). Overall, there has been a worldwide increase in the incidence of new Borrelia infections in the last 10 years, with 15 new species (1990-2010). These species include in the USA: B. burgdorferi sensu strictu, Borrelia sensu latu, and Borrelia kurtenbachii species; in Europe: Borrelia afzelii (ACA), Borrelia garinii (neuroborreliosis), B. spielmani (early skin disease), B. valaisana, B. lusitanea, and B. bavariensis; in Asia, B. japonica, B. turdi, B. tanukii, B.yangtze; in North America, Borrelia andersonii; in the southern U.S, B. americanum, and B. carolinensis; and in the Pacific U.S, B. bissettii. We have also seen an expansion of viral infections in ticks in the last few years, such as the recently discovered Heartland and Bourbon viruses, and Powassan virus.

This new Anaplasma species joins the tick-transmitted bacteria of the genera Neorickettsia, Anaplasma, and Ehrlichia. Ehrlichiosis includes HSE (N. sennetsu), HGA (A. phagocytophilum), HME (E. chaffeensis), HEE (E. ewingii) and HWME (E. Wisconsin-Minn), As is the case with Anaplasma capra, there are no specific tests for all of these species (i.e.,E. ewingii: Human Babesiosis and Ehrlichiosis-Current Status. Shah, J., Horowitz, R., Eur Infect Dis, Vol 6, Issue 1, Spring 2012), so patients may become ill without an apparent etiology . Anaplasma species may also be transmitted by blood transfusion (Annen, K., et al. Two cases of Transfusion-Transmitted Anaplasma phagocytophilum. American Journal of Clinical Pathology. 2012 Apr;137(4):562-5). It is therefore imperative that our surveillance efforts for tick-borne diseases include regularly testing ticks for novel infections, both in the US and worldwide, as the number and type of these infections is rapidly expanding.

Substantial health threat: Never-before-seen tick-borne disease, Science Daily