Background Tick-borne diseases are of substantial concern worldwide in both humans and animals. Several hard tick species are of medical and veterinary interest in Europe, and changes in the range of tick species can affect the spread of zoonotic pathogens. The aim of the present study was to map the current prevalence and distribution pattern of ticks and related tick-borne pathogens in Latvia, a Baltic state in northern Europe. Methods Nearly 4600 Ixodes ricinus , I. persulcatus and Dermacentor reticulatus tick samples were collected in all regions of Latvia during 2017–2019 and were screened by molecular methods to reveal the prevalence and distribution pattern of a wide spectrum of tick-borne pathogens. Results New localities of D. reticulatus occurrence were found in western and central Latvia, including the Riga region, indicating that the northern border of D. reticulatus in Europe has moved farther to the north. Among the analyzed ticks, 33.42% carried at least one tick-borne pathogen, and 5.55% of tick samples were positive for two or three pathogens. A higher overall prevalence of tick-borne pathogens was observed in I. ricinus (34.92%) and I. persulcatus (31.65%) than in D. reticulatus (24.2%). The molecular analysis revealed the presence of tick-borne encephalitis virus, Babesia spp., Borrelia spp., Anaplasma phagocytophilum and Rickettsia spp. Overall, 15 and 7 tick-borne pathogen species were detected in Ixodes spp. and D. reticulatus ticks, respectively. This is the first report of Borrelia miyamotoi in Latvian field-collected ticks. Conclusions This large-scale countrywide study provides a snapshot of the current distribution patterns of Ixodes and Dermacentor ticks in Latvia and gives us a reliable overview of tick-borne pathogens in Latvian field-collected ticks.

BackgroundDifferent tick species are able to transmit different pathogens, and tick-borne diseases are of substantial concern worldwide for both humans and animals. Environmental changes and changes in the range of tick species, including Dermacentor reticulatus in Europe, can affect the spread of zoonotic pathogens. The aim of this study was to investigate the prevalence of the tick-borne pathogens in ticks removed from dogs in Latvia, and to explore possible changes between years 2011 and 2016.ResultsIn 2011, only Ixodes ticks (221 Ixodes ricinus and 22 Ixodes persulcatus) were collected from dogs, while in 2016 tick samples belonged to Ixodes ricinus (360), Ixodes persulcatus (2) and Dermacentor reticulatus (27) species. In total, 35.8 and 40.0% of adult ticks were pathogen-positive in 2011 and 2016, respectively; the difference was not statistically significant (P > 0.05). The molecular analysis indicated the presence of 13 tick-borne microorganisms; the most prevalent pathogen was Rickettsia, followed by Borrelia burgdorferi sensu lato group spirochetes, Anaplasma phagocytophilum and Babesia species. Borrelia miyamotoi was also present. A co-infection with two and three tick-borne pathogens was detected in 7.9 and 7.4% of Ixodes ricinus and Dermacentor reticulatus, respectively. The results of this study confirmed that the spread of novel vectors could bring additional risk of exposure to novel emerging pathogens to pets and their owners, as both Babesia canis and Rickettsia raoultii were shown to be highly associated with Dermacentor reticulatus ticks in Latvia.ConclusionsThis study demonstrates the potential danger from the inadvertent introduction of novel disease pathogens and vectors. Awareness of co-infections and Dermacentor reticulatus-related pathogens needs to be increased.

No abstract

Background: Urogenital tuberculosis (TB) is rare in children and usually develops due to reactivation of the foci in the genitourinary tract after the latency period following initial infection. Urogenital TB in children has no pathognomonic clinical features that can result in overlooking or misdiagnosing this clinical entity. Here, we report important findings regarding the pathogenesis and transmission of TB by using genotyping and whole-genome sequencing (WGS) in a study of renal TB case in a child. Case presentation: A 13-year-old boy was admitted to the hospital because of high fever, severe dry cough, flank pain and painful urination. Abdominal ultrasonography and CT revealed an 8 mm calculus in the kidney, and clinical findings were initially interpreted as nephrolithiasis. Nevertheless, due to the atypical clinical presentation of kidney stone disease, additional investigations for possible TB were performed. The QuantiFERON®-TB Gold Plus test was positive, and the Mantoux test resulted in 15 mm of induration, confirming infection with Mycobacterium tuberculosis (Mtb). Chest X-ray was normal. Chest CT revealed calcified intrathoracic lymph nodes. The urine sample tested positive for acid-fast bacilli, and Mtb cultures were obtained from urine and bronchial aspirate samples, resulting in a final diagnosis of intrathoracic lymph node and renal TB. Contact investigation revealed that the child's father was diagnosed with TB when the child was 1 year old. Genotyping and WGS analysis of Mtb isolates of the child and his father confirmed the epidemiological link and pointed to the latency of infection in the child. Conclusions: This case report confirmed the development of active TB from calcified lesions in adolescent after 12 years of exposure, demonstrated the absence of microevolutionary changes in the Mtb genome during the period of latency, and proved the importance of appropriate evaluation and management to prevent the progression of TB infection to active TB disease. The use of WGS provided the ultimate resolution for the detection of TB transmission and reactivation events.