Taxonomic corrections to species of Rhyparochromidae (Hemiptera: Heteroptera) described by Carl Peter Thunberg.

Types of Rhyparochromidae (Hemiptera: Heteroptera: Lygaeoidea) species described by Carl Peter Thunberg, deposited in the Museum of Evolution (formerly Zoologiska Institut), Uppsala University, Uppsala, Sweden, were reexamined and the taxonomic and nomenclatural problems that existed among those species discussed and resolved as required. Lectotypes are designated for Cimex caffer Thunberg, 1784, Lygaeus ater Thunberg, 1822, Lygaeus biguttatus Thunberg, 1822, and Pendulinus guttatus Thunberg, 1825. The lectotype of Pendulinus (now Metochus) guttatus is designated as neotype of Pendulinus (now Metochus) uniguttatus Thunberg, 1822; as a result the former name becomes junior objective synonym of the latter. The following taxonomic changes are proposed: Lethaeus ater (Thunberg, 1822), new combination (from Lygaeus); Migdilybs biguttatus (Thunberg, 1822), new combination (from Lygaeus) = Migdilybs furcifer Hesse, 1925, new subjective synonym; Metochus uniguttatus (Thunberg, 1822) = Metochus bengalensis (Dallas, 1852), confirmed subjective synonym = Metochus yeh (Dohrn, 1860), confirmed subjective synonym; Raglius alboacuminatus (Goeze, 1778) = Cimex caffer Thunberg, 1874, confirmed subjective synonym. Lethaeus barberi Slater, 1964 does not belong to Lethaeus Dallas, 1852 but currently it cannot be placed with confidence in any existing genus. 

Dissemination of spotted fever rickettsia agents in Europe by migrating birds.

Migratory birds are known to play a role as long-distance vectors for many microorganisms. To investigate whether this is true of rickettsial agents as well, we characterized tick infestation and gathered ticks from 13,260 migratory passerine birds in Sweden. A total of 1127 Ixodes spp. ticks were removed from these birds and the extracted DNA from 957 of them was available for analyses. The DNA was assayed for detection of Rickettsia spp. using real-time PCR, followed by DNA sequencing for species identification. Rickettsia spp. organisms were detected in 108 (11.3%) of the ticks. Rickettsia helvetica, a spotted fever rickettsia associated with human infections, was predominant among the PCR-positive samples. In 9 (0.8%) of the ticks, the partial sequences of 17kDa and ompB genes showed the greatest similarity to Rickettsia monacensis, an etiologic agent of Mediterranean spotted fever-like illness, previously described in southern Europe as well as to the Rickettsia sp.IrITA3 strain. For 15 (1.4%) of the ticks, the 17kDa, ompB, gltA and ompA genes showed the greatest similarity to Rickettsia sp. strain Davousti, Rickettsia japonica and Rickettsia heilongjiangensis, all closely phylogenetically related, the former previously found in Amblyomma tholloni ticks in Africa and previously not detected in Ixodes spp. ticks. The infestation prevalence of ticks infected with rickettsial organisms was four times higher among ground foraging birds than among other bird species, but the two groups were equally competent in transmitting Rickettsia species. The birds did not seem to serve as reservoir hosts for Rickettsia spp., but in one case it seems likely that the bird was rickettsiemic and that the ticks had acquired the bacteria from the blood of the bird. In conclusion, migratory passerine birds host epidemiologically important vector ticks and Rickettsia species and contribute to the geographic distribution of spotted fever rickettsial agents and their diseases.

Migrating birds and tickborne encephalitis virus.

During spring and autumn 2001, we screened 13,260 migrating birds at Ottenby Bird Observatory, Sweden, and found 3.4% were infested with ticks. Four birds, each a different passerine species, carried tickborne encephalitis virus (TBEV)-infected ticks (Ixodes ricinus). Migrating birds may play a role in the geographic dispersal of TBEV-infected ticks.

Migratory passerine birds as reservoirs of Lyme borreliosis in Europe.

To define the role of birds as reservoirs and disseminators of Borrelia spirochetes, we characterized tick infestation and reservoir competence of migratory passerine birds in Sweden. A total of 1,120 immature Ixodes ricinus ticks were removed from 13,260 birds and assayed by quantitative polymerase chain reaction (PCR) for Borrelia, followed by DNA sequencing for species and genotype identification. Distributions of ticks on birds were aggregated, presumably because of varying encounters with ticks along migratory routes. Lyme borreliosis spirochetes were detected in 160 (1.4%) ticks. Borrelia garinii was the most common species in PCR-positive samples and included genotypes associated with human infections. Infestation prevalence with infected ticks was 5 times greater among ground-foraging birds than other bird species, but the 2 groups were equally competent in transmitting Borrelia. Migratory passerine birds host epidemiologically important vector ticks and Borrelia species and vary in effectiveness as reservoirs on the basis of their feeding behavior.