Prevalence of Anaplasma phagocytophilum and its coinfection with Borrelia afzelii in Ixodes ricinus and Ixodes persulcatus ticks inhabiting Tver Province (Russia) – a sympatric region for both tick species

Abstract

Human granulocytic anaplasmosis (HGA) and Lyme borreliosis (LB) are tick-borne infectious diseases caused by Anaplasma phagocytophilum and Borrelia burgdorferi sensu lato species, respectively. In this study, p44/msp2 paralogues specific to A. phagocytophilum and 5S-23S rRNA gene-intergenic spacers specific to B. burgdorferi sensu lato species were detected by PCR in ticks collected in two regions, Tver (Kalinin) and Konakovo, of the Tver (Kalinin) Province located 150 km north-west of Moscow. The PCR amplicons obtained were further characterized by sequencing and RFLP analysis. In the total of 199 ticks collected, 8.8 % (7/80) and 33.8 % (27/80) of Ixodes ricinus, and 2.5 % (3/119) and 45.4 % (54/119) of Ixodes persulcatus, were found to be infected with A. phagocytophilum and B. burgdorferi sensu lato spp., respectively. Of those 199 ticks, 5 (2.5 %) were coinfected with A. phagocytophilum and Borrelia afzelii. Phylogenetic analysis revealed unique p44/msp2 paralogous genes in A. phagocytophiluminfected Russian ticks. The sequence similarities with those of A. phagocytophilum in the United States, UK and Japan ranged from 42 % to 80.4 %, and there were no sequences showing more than 90 % similarity with those sequences from the other countries. The results showed that the p44/msp2 sequence similarity groups may provide an index of adaptation of A. phagocytophilum strains to specific vector ticks or reservoir hosts in different countries and areas. These findings suggest that there is a public health threat from HGA and LB in Tver Province surrounding Moscow. INTRODUCTIONHuman granulocytic anaplasmosis (HGA) and Lyme borreliosis (LB) are tick-borne and emerging infectious diseases caused by Anaplasma phagocytophilum (formerly Ehrlichia phagocytophila, revised by Dumler et al., 2001) and Borrelia burgdorferi sensu lato species. HGA is a febrile systemic illness and the severity of this disease ranges from asymptomatic seroconversion to death. The first case of human infection by A. phagocytophilum was found in the United States in 1994 (Chen et al., 1994). Since then, the number of patients has increased in the United States (Dumler et al., 2005). In Europe, the first human cases of this disease were described in 1997 (Petrovec et al., 1997), and serological and PCR analyses suggest that A. phagocytophilum is distributed throughout Europe and in some parts of the Middle East and Asia (Blanco & Oteo, 2002;Cao et al., 2000; Heo et al., 2002;Keysary et al., 1999). LB is the most common tick-borne infectious disease in the Northern Hemisphere (Masuzawa, 2004;Steere, 2001 METHODSSurvey area and tick sampling. During the summer of 2002, unfed adult ticks (I. persulcatus and I. ricinus) were collected from vegetation by a dragging method using 1 m 2 flannel flags, in the Tver (Kalinin) and Konakovo regions of the Tver Province, which are located 110-150 km north-west from Moscow. Vegetation in the survey area consists of Russian plain and forest (aspen, firs and birches) with bushes. The areas are mostly forest with l...

Identification of Anaplasma phagocytophilum in tick populations in Estonia, the European part of Russia and Belarus

“…However, A. phagocytophilum has previously been reported simultaneously in I. persulcatus and I. ricinus at geographical sites where the two tick species are distributed. Moreover, sequences of the A. phagocytophilum p44/msp2 gene indicated that there are no differences between sequences derived from I. ricinus and I. persulcatus [23]. In Estonia, even at two sites in south‐eastern Estonia, where both species of ticks co‐circulate and I. ricinus constitutes the minority (10–20%) of the tick population, we found A. phagocytophilum only in I. ricinus ; thus, the role of I. persulcatus for the circulation of A. phagocytophilum in Estonia is unclear and further tick collections are necessary.…”

Molecular-genetic and ultrastructural characteristics of ‘Candidatus Ehrlichia khabarensis’, a new member of the Ehrlichia genus

“…I. persulcatus ticks inhabiting the Far East were shown to be infected by the same Anaplasmataceae bacteria -Anaplasma phagocytophilum, E. muris, and 'Candidatus Neoehrlichia mikurensis' -as I. persulcatus in other parts of their distributive area (Eremeeva et al, 2006;Shpynov et al, 2006;Masuzawa et al, 2008;Rar et al, 2010). In addition, a new genetic variant of Anaplasma bovis was found in H. concinna ticks, and two distinct Ehrlichia genetic variants were found, namely Ehrlichia sp.…”

Mechanisms of Obligatory Intracellular Infection with Anaplasma phagocytophilum

“…Although Ixodes ticks often feed on white-tailed deer, the deer are infected with the Ap-Variant 1 strain of A. phagocytophilum, rather than with the human strain, in the United States (146). Diverse A. phagocytophilum strains are also found in animals and ticks in Europe, Japan, and Russia (109,111,151,160,170,203,238,239), where HGA has been rarely reported. These findings imply that the zoonosis potential of A. phagocytophilum depends not only on the transmissibility, habitats, and population density of ticks and infected mammals (90) but also on the genetic variations of A. phagocytophilum.…”