Seroprevalence of antibodies against Borrelia burgdorferi sensu lato in healthy blood donors in Romania: an update

Abstract

Background The Borrelia burgdorferi sensu lato (s.l.) genogroup is the causative agent responsible for Lyme borreliosis, a common tick-borne infectious disease in some temperate regions of the Northern Hemisphere. In humans, the clinical manifestations of Lyme borreliosis vary from dermatological infection to severe systemic manifestations. In Romania, data on the seroprevalence of Lyme borreliosis and associated risk factors are scarce and outdated, as the only seroprevalence study with a large dataset was published more than 20 years ago. Therefore, the aim of the present study was to evaluate the seroprevalence for Borrelia burgdorferi s.l. in healthy blood donors from six Romanian counties and identify the associated risk factors. Methods The study was conducted among 1200 healthy blood donors aged between 18 and 65 years during November 2019 and September 2020 from six counties in the northwestern and central parts of Romania. A two-tiered testing strategy was applied. Positive and equivocal immunoenzymatic test results for IgG and IgM antibodies were further confirmed by Western blot. Results Serum samples from 20% of the blood donors had positive or equivocal IgG and IgM ELISA index values. In total, 2.3% of the serum samples for IgG and 1.8% for IgM were positive by Western blot. The seroprevalence for both antibodies varied between 1.5% (Satu-Mare) and 6.5% (Bistrița-Năsăud) in the six counties investigated. The highest seroprevalence was observed in men (4.7%), in blood donors performing their professional activities outdoors (4.2%), and in those aged ≥ 56 years (8%). Conclusions These findings confirm the presence of specific IgG and IgM antibodies to B. burgdorferi s.l. among healthy blood donors from Romania. Furthermore, potential risk factors, such as gender, age, and behavior, associated with the presence of positive B. burgdorferi s.l. antibodies among healthy blood donors were identified. Graphical Abstract

Seroprevalence Rates against West Nile, Usutu, and Tick-Borne Encephalitis Viruses in Blood-Donors from North-Western Romania

“…Human blood samples from healthy donors were collected between November 2019 and February 2020 and between August and September 2020 by the Regional Blood Transfusion Centers in six counties from the north-western region of Romania (Alba (AB), Cluj (CJ), Sălaj (SJ), Bistrit , a-Năsăud (BN), Maramures , (MM), and Satu-Mare (SM)), as previously described [38]. Two hundred samples were analyzed per county, resulting in a total of 1200 samples being assessed in the current study.…”

“…The study group consisted of 1200 samples collected from healthy blood donors in six counties from the north-western region of Romania (200 samples from each county), as previously described [38]. Briefly, the age of the study participants varied between 18 and 65 years, with a median age of 41 years (interquartile range .…”

Seroepidemiology of Borrelia burgdorferi s.l. among German National Cohort (NAKO) Participants, Hanover

“…In addition, we are the first to report that both decreasing BMI and self-reported depression symptomatology are independently associated with positive IgG serostatus. We applied three classification definitions to determine seropositive blood samples to facilitate comparisons with (inter-) national serosurveys, as researchers have been using different definitions [22,24,58], which considerably affect the reported proportion of seropositivity [24], which we also demonstrated in our work.…”

Regional seropositivity for Borrelia burgdorferi and associated risk factors: findings from the Rhineland Study, Germany

“…Woudenberg et al [ 30 ] and Wilking et al [ 32 ] used a more sensitive classification for their serosurvey results, as they additionally classified borderline line blot results with prior positive ELISA as positive. On the contrary, Kalmár et al [ 34 ] applied a classification of seropositive samples corresponding to MIQ 12. Moreover, some studies have additionally reported serological results that have been corrected for sample deviations from the general population [ 32 ].…”

“…Moreover, some studies have additionally reported serological results that have been corrected for sample deviations from the general population [ 32 ]. These differences in classification and testing procedures, such as utilizing different test kits, make it difficult to compare the results between studies [ 30 , 32 , 34 ].…”