Detection and prevalence of Anaplasma phagocytophilum and Rickettsia helvetica in Ixodes ricinus ticks in seven study areas in Sweden

• BACKGROUND: Tick-borne Anaplasma phagocytophilum and Rickettsia spp. are considered to be emerging human pathogens, but only limited data are available on their occurrence in Sweden. Two real-time PCR assays followed by nested PCR and sequence analysis were carried out to investigate the prevalence of A. phagocytophilum and spotted fever rickettsiae in ticks from seven areas in Sweden. RESULTS: In 139 pooled samples, representing a total of 1245 Ixodes ricinus ticks (204 larvae, 963 nymphs, 38 males, 40 females), the overall positive mean infection prevalence was 1.3-15.0% for A. phagocytophilum and 1.5-17.3% for R. helvetica . A. phagocytophilum was only detected in nymphs (1.7-19.4%), whereas R. helvetica was detected in all three tick stages. Support for vertical and transstadial transmission was only obtained for R. helvetica . Both agents showed similar infection rates across study areas, although infection rates were greater in coastal areas. CONCLUSIONS: The results show that both pathogens occurred in all seven locations, indicating that they are prevalent in Sweden and should be considered etiological agents in patients recently bitten by ticks.

Subject headings

Medical and Health Sciences  (hsv)

Basic Medicine  (hsv)

Microbiology in the medical area  (hsv)

Medicin och hälsovetenskap  (hsv)

Medicinska grundvetenskaper  (hsv)

Mikrobiologi inom det medicinska området  (hsv)

Medical and Health Sciences  (hsv)

Clinical Medicine  (hsv)

Infectious Medicine  (hsv)

Medicin och hälsovetenskap  (hsv)

Klinisk medicin  (hsv)

Infektionsmedicin  (hsv)

Natural Sciences  (hsv)

Biological Sciences  (hsv)

Biological Systematics  (hsv)

Naturvetenskap  (hsv)

Biologiska vetenskaper  (hsv)

Biologisk systematik  (hsv)

MEDICINE  (svep)

Microbiology, immunology, infectious diseases  (svep)

Microbiology  (svep)

Bacteriology  (svep)

MEDICIN  (svep)

Mikrobiologi, immunologi, infektionssjukdomar  (svep)

Mikrobiologi  (svep)

Bakteriologi  (svep)

MEDICINE  (svep)

Microbiology, immunology, infectious diseases  (svep)

Infectious diseases  (svep)

MEDICIN  (svep)

Mikrobiologi, immunologi, infektionssjukdomar  (svep)

Infektionssjukdomar  (svep)

NATURAL SCIENCES  (svep)

Biology  (svep)

Organism biology  (svep)

Systematics and phylogenetics  (svep)

NATURVETENSKAP  (svep)

Biologi  (svep)

Organismbiologi  (svep)

Systematik och fylogeni  (svep)

Clinical Bacteriology  (uu)

Klinisk bakteriologi  (uu)

Biologi med inriktning mot systematik  (uu)

Biology with specialization in Systematics  (uu)

Keyword

Rickettsia

Anaplasma

Ehrlichia

Ixodes ricinus

Ticks

Sweden

anaplasmosis

rickettsiosis