Manifestaciones articulares en enfermos de Lyme

Occurrence of Borrelia and Borreliella species in Ixodes ricinus collected from roe deer in northwestern Spain

Ixodes ricinus, comprising the predominant tick species in Europe, can transmit important human pathogens, including Borreliella spp., the causal agent of Lyme borreliosis. One hundred and seventy five roe deer hunted in two areas (plateau and mountain) of Galicia (northwest Spain) were examined for the presence of ticks; all roe deer were infested by I. ricinus. Nymphs (n = 1000), males (n = 1449) and females (n = 1000) of I. ricinus were analysed in pools of up to 10 ticks to detect both Borreliella and Borrelia DNA. The average number of I. ricinus per roe deer was similar in both areas, regardless of the life stage; although the percentage of Borreliella and Borrelia positive pools was higher in ticks collected from roe deer hunted in the plateau area, no significant differences were detected. Sequence analysis at the flagellin gene allowed the identification of four Borreliella species (Borreliella afzelii, Borreliella garinii, Borreliella lusitaniae and Borreliella valaisiana) and Borrelia miyamotoi in adult males; only B. valaisiana and B. miyamotoi were detected in nymphs and all females were negative. All Borreliella and Borrelia species found in roe deer were previously identified in questing I. ricinus collected in the same study area, although the prevalence was lower in the present study. The analysis of male I. ricinus ticks collected from roe deer gives a good estimation of Borreliella diversity in questing ticks.

Molecular identification of Borrelia spirochetes in questing Ixodes ricinus from northwestern Spain

BACKGROUND

Ixodes ricinus, the predominant tick species in Europe, can transmit the causative agents of important human diseases such as Lyme borreliosis (LB), caused by Borrelia spirochetes. In northern Spain, LB is considered endemic; recently, a significant increase of the annual incidence of LB was reported in the northwestern (NW) region.

METHODS

In order to provide information on the prevalence of Borrelia spp., pooled and individually free-living I. ricinus from NW Spain were molecularly analyzed. Positive samples were characterized at the fla and Glpq genes and the rrfA-rrlB intergenic spacer region to identify Borrelia species/genospecies.

RESULTS

Borrelia burgdorferi (sensu lato) (s.l.) individual prevalence and MIR were significantly higher in adult females (32.3 and 16%) than in nymphs (18.8 and 6.2%) and adult males (15.6 and 8.4%). Five Borrelia genospecies belonging to the B. burgdorferi (s.l.) group were identified: B. garinii was predominant, followed by B. valaisiana, B. lusitaniae, B. afzelii and B. burgdorferi (sensu stricto) (s.s.). One species belonging to the tick-borne relapsing fever group (B. miyamotoi) was also found, showing low individual prevalence (1%), positive pool (0.7%) and MIR (0.1%) values. To our knowledge, this is the first citation of B. miyamotoi in free-living ticks from Spain.

CONCLUSIONS

The significant prevalences of B. burgdorferi (s.l.) genospecies detected in questing ticks from NW Spain are similar to those detected in northern and central European countries and higher to those previously found in Spain. These results together with the high incidence of LB in humans and the high seroprevalence of B. burgdorferi (s.l.) in roe deer shown in other studies reveal that the northwest area is one of the most risky regions for acquiring LB in Spain.

[Usefulness of serological studies for the early diagnosis of Lyme disease in Primary Health Care Centres]

Objetivo

Determinar la utilidad del diagnóstico precoz de la enfermedad de Lyme (EL) en los Centros de Atención Primaria (CAP) empleando el ELISA como técnica de cribado serológico.

Métodos

Se realiza un estudio retrospectivo (2006-2013) consistente en la determinación mediante ELISA de la seropositividad a Borrelia de 2.842 personas consideradas en riesgo de padecer EL. Se estudia la relación entre el hábitat y la zona de residencia de las personas con seropositividad a Borrelia, según la procedencia de las muestras (CAP/Hospital).

Resultados

El 15,2% de los sueros resultaron positivos frente a Borrelia spp. La seropositividad fue significativamente superior en las muestras remitidas desde los CAP que desde el Hospital y en los habitantes del rural y la montaña frente al área urbana y la meseta. El porcentaje de seropositividad se incrementó con el transcurso de los años.

Los médicos de Atención Primaria detectaron mayor porcentaje de enfermos de Lyme en Fase I y tras la instauración del tratamiento no se observaron secuelas.

Conclusiones

El papel del médico de atención primaria es primordial en el diagnóstico precoz de la EL, constatándose un mayor porcentaje de seropositivos entre las muestras remitidas desde los CAP con predominio del diagnóstico en Fase I de enfermedad y la resolución sin secuelas.

La detección de anticuerpos específicos frente a Borrelia, mediante ELISA, es una prueba útil para el cribado de pacientes en riesgo de EL.