New Species Behind Leprosy?

There have been discussions on the role of a novel species of Mycobacterium, M. lepromatosis, in the causation of Leprosy for a long time now. In 2008, Han and colleagues (1) found the novel bacterium as the causative organism behind diffuse lepromatous leprosy. A new paper (2) published in the Proceedings of the National Academy of Sciences (PNAS) has further strengthened the premise of a novel species causing leprosy by conducting a whole genome study.

The concept that Mycobaterium leprae is the only causative organism behind the disfiguring disease which has almost been eliminated from many parts of the world, now stands challenged by the emergence of this new evidence. The contribution of this new species to the overall case load and what implications it holds for public health approaches to control the disease in the long run needs to be reexamined.
The new paper, by Singha et al, has isolated Mycobacterium lepromatosis from the skin lesions of a patient suffering from diffuse lepromatous leprosy and has conducted a whole genome sequencing, followed by comparison with that of the Mycobacterium leprae, to establish the unique identities of the two different organisms.

References:

1. Han XY, Seo YH, Sizer KC, Schoberle T, May GS, Spencer JS, Li W, Nair RG. A new _Mycobacterium_ species causing diffuse lepromatous leprosy. Am J Clin Pathol. 2008 Dec;130(6):856-64. doi: 10.1309/AJCPP72FJZZRRVMM.
2. Singha P, Benjaka A, Schuenemannb VJ, Herbigb A, et al. Insight into the evolution and origin of leprosy bacilli from the genome sequence of Mycobacterium lepromatosis. PNAS. March 18, 2015. doi: 10.1073/pnas.1421504112.

Novel Tick-Borne Anaplasma Maybe Transmitted to Human from Infected Goats

A new study from China, published in the Lancet Infectious Diseases journal, contends that a novel, tick-borne Anaplasmosis maybe transmitted from infected goats to human beings in contact. The abstract of the study is given below:

Summary

Background

Anaplasma phagocytophilum and Anaplasma ovis cause human infections. We investigated the potential for human pathogenicity of a newly discovered Anaplasma species infecting goats in China.

Methods

We collected blood samples from patients with a history of tick bite in the preceding 2 months at Mudanjiang Forestry Central Hospital of Heilongjiang Province from May 1, to June 10, 2014, to detect the novel Anaplasma species by PCR. We inoculated positive samples into cell cultures. We characterised the isolated pathogen by morphological and phylogenetic analyses. We tested serum antibodies by indirect immunofluorescence assay.

Findings

28 (6%) of 477 patients assessed were infected with the novel Anaplasma species according to PCR and sequencing. We isolated the pathogen in vitro from three patients. Phylogenetic analyses of rrs, gltA, groEL, msp2, and msp4 showed that the pathogen was distinct from all known Anaplasmaspecies. We provisionally nominate it “Anaplasma capra”. 22 (92%) of 24 patients with data available had seroconversion or a four-fold increase in antibody titres. All 28 patients developed non-specific febrile manifestations, including fever in 23 (82%), headache in 14 (50%), malaise in 13 (46%), dizziness in nine (32%), myalgia in four (14%), and chills in four (14%). Additionally, ten (36%) of 28 patients had rash or eschar, eight (29%) had lymphadenopathy, eight (29%) had gastrointestinal symptoms, and three (11%) had stiff neck. Five patients were admitted to hospital because of severe disease. Six (35%) of 17 patients with data available had high hepatic aminotransferase concentrations.

Interpretation

The emergence of “A capra” as a cause of human disease suggests that individuals living in or travelling to endemic regions in northern China should take precautions to reduce their risk of exposure to this novel tick-borne pathogen.

Reference

Li H, Zheng Y-C, Ma L, et al. Human infection with a novel tick-borne_Anaplasma_ species in China: a surveillance study. Lancet InfectiousDiseases. Published Online: 29 March 2015. DOI:http://dx.doi.org/10.1016/S1473-3099(15)70051-4. Available at: LINK