Anaplasma bovis-Like Infections in Humans, United States, 2015-2017.

We detected the DNA of an Anaplasma bovis-like bacterium in blood specimens from 4 patients from the United States with suspected tickborne illnesses. Initial molecular characterization of this novel agent reveals identity to A. bovis-like bacteria detected in Dermacentor variabilis ticks collected from multiple US states.

A Method for Dynamically Selecting the Best Frequency Hopping Technique in Industrial Wireless Sensor Network Applications.

Industrial wireless applications often share the communication channel with other wireless technologies and communication protocols. This coexistence produces interferences and transmission errors which require appropriate mechanisms to manage retransmissions. Nevertheless, these mechanisms increase the network latency and overhead due to the retransmissions. Thus, the loss of data packets and the measures to handle them produce an undesirable drop in the QoS and hinder the overall robustness and energy efficiency of the network. Interference avoidance mechanisms, such as frequency hopping techniques, reduce the need for retransmissions due to interferences but they are often tailored to specific scenarios and are not easily adapted to other use cases. On the other hand, the total absence of interference avoidance mechanisms introduces a security risk because the communication channel may be intentionally attacked and interfered with to hinder or totally block it. In this paper we propose a method for supporting the design of communication solutions under dynamic channel interference conditions and we implement dynamic management policies for frequency hopping technique and channel selection at runtime. The method considers several standard frequency hopping techniques and quality metrics, and the quality and status of the available frequency channels to propose the best combined solution to minimize the side effects of interferences. A simulation tool has been developed and used in this work to validate the method.

First Records of Established Populations of Ixodes scapularis (Acari: Ixodidae) Collected From Three Nebraska Counties.

Reported cases of Lyme disease in Nebraska have been assumed to be imported from other endemic areas. Previous surveillance efforts provided no evidence of established populations as only individual specimens of Ixodes scapularis (Say) had been collected. In the winter of 2018, adult I. scapularis were found on a dog at Two Rivers State Recreation Area, Douglas County, prompting tick collection at the site and nearby natural areas. In May 2019, all life stages of host-seeking I. scapularis were collected using dragging and flagging techniques in sites located near the Platte River in Douglas, Sarpy, and Saunders counties. This is the first documentation of established populations of I. scapularis in Nebraska.

Climate and tick seasonality are predictors of Borrelia burgdorferi genotype distribution.

The blacklegged tick, Ixodes scapularis, is of significant public health importance as a vector of Borrelia burgdorferi, the agent of Lyme borreliosis. The timing of seasonal activity of each immature I. scapularis life stage relative to the next is critical for the maintenance of B. burgdorferi because larvae must feed after an infected nymph to efficiently acquire the infection from reservoir hosts. Recent studies have shown that some strains of B. burgdorferi do not persist in the primary reservoir host for more than a few weeks, thereby shortening the window of opportunity between nymphal and larval feeding that sustains their enzootic maintenance. We tested the hypothesis that climate is predictive of geographic variation in the seasonal activity of I. scapularis, which in turn differentially influences the distribution of B. burgdorferi genotypes within the geographic range of I. scapularis. We analyzed the relationships between climate, seasonal activity of I. scapularis, and B. burgdorferi genotype frequency in 30 geographically diverse sites in the northeastern and midwestern United States. We found that the magnitude of the difference between summer and winter daily temperature maximums was positively correlated with the degree of seasonal synchrony of the two immature stages of I. scapularis. Genotyping revealed an enrichment of 16S-23S rRNA intergenic spacer restriction fragment length polymorphism sequence type 1 strains relative to others at sites with lower seasonal synchrony. We conclude that climate-associated variability in the timing of I. scapularis host seeking contributes to geographic heterogeneities in the frequencies of B. burgdorferi genotypes, with potential consequences for Lyme borreliosis morbidity.

Field estimation of the flock-level diagnostic specificity of an enzyme-linked immunosorbent assay for Avian metapneumovirus antibodies in turkeys.

Routine serologic testing for Avian metapneumovirus (AMPV) infection of turkey flocks at slaughter is currently being used to monitor changes in the occurrence of AMPV infection in endemic areas and can also be used to detect the emergence of infection in currently unaffected areas. Because of the costs associated with false-positive results, particularly in areas that are free of AMPV infection, there is a need to obtain improved estimates of flock-level specificity (SP). The objective of this study was to estimate flock-level SP of a program to monitor AMPV infection in turkey flocks at processing using a standard enzyme-linked immunosorbent assay (ELISA). A study was carried out in which 37 AMPV-free flocks from 7 Midwest operations were followed serologically. Six percent, 3%, and 0.2% of total samples tested AMPV positive at 8 weeks, 12 weeks, and at processing, respectively. Overall, flock-level SP increased as the cutoff increased and as age increased. Flock-level SP at processing was 97%, if a cutoff of 1 was used (the flock was classified as positive if at least 1 sample tested positive), and 100%, if any other cutoff was used. Administration of antibiotics (P = 0.02) and vaccination for Bordetella avium (P = 0.08) were positively associated with the probability of (false) positive test results. These findings suggest possible cross-reactions with other infections and highlight the need to consider variable diagnostic performance depending on farm conditions.

Ectoparasites of cattle and small ruminants.

Arthropod ectoparasites are the most ubiquitous life forms affecting ruminant animals and commonly affect the daily activity and health status of ruminants. This article describes the phenology of several important ectoparasites of livestock and small ruminants, and delineates some general control and management strategies for protecting domestic ruminants.

Note on Ehrlichia chaffeensis, Ehrlichia ewingii, and "Borrelia lonestari" infection in lone star ticks (Acari: Ixodidae), Nebraska, USA.

The lone star tick, Amblyomma americanum (L.) (Acari: Ixodidae), is established in southeastern Nebraska yet the prevalence of tick-associated microorganisms is not known. An initial PCR-based analysis for Ehrlichia chaffeensis, Ehrlichia ewingii, and Borrelia infection in host-seeking adult ticks collected in southeast Nebraska was conducted. A total of 251 adult ticks collected in six sites in southeast Nebraska were tested. E. chaffeensis, E. ewingii, and Borrelia spp. were present, and the prevalence of each was approximately 1.6%. This study demonstrates that Ehrlichia spp. are present in Nebraska lone star tick populations.

Human risk of infection with Borrelia burgdorferi, the Lyme disease agent, in eastern United States.

The geographic pattern of human risk for infection with Borrelia burgdorferi sensu stricto, the tick-borne pathogen that causes Lyme disease, was mapped for the eastern United States. The map is based on standardized field sampling in 304 sites of the density of Ixodes scapularis host-seeking nymphs infected with B. burgdorferi, which is closely associated with human infection risk. Risk factors for the presence and density of infected nymphs were used to model a continuous 8 km×8 km resolution predictive surface of human risk, including confidence intervals for each pixel. Discontinuous Lyme disease risk foci were identified in the Northeast and upper Midwest, with a transitional zone including sites with uninfected I. scapularis populations. Given frequent under- and over-diagnoses of Lyme disease, this map could act as a tool to guide surveillance, control, and prevention efforts and act as a baseline for studies tracking the spread of infection.

Renal infection by a new coccidian genus in big brown bats (Eptesicus fuscus).

A novel coccidian parasite from the kidney of big brown bats (Eptesicus fuscus) is described. This coccidian (Nephroisospora eptesici nov. gen., n. sp.) was associated with a generally mild, focal or multifocal, well-demarcated cortical renal lesion less than 1 mm in diameter. The lesion represented cystic, dilated tubules with hypertrophied tubular epithelial cells and was present in the kidneys of 29 of 590 bats. Numerous coccidian parasites in various stages of development were present within the tubular epithelial cells and within the cyst lumina. Oocysts were collected from cystic dilated tubules. Thin-walled, sporulated ellipsoidal oocysts measuring an average of 18.9 x 20.8 microm were present in kidney tissue. The oocysts contained 2 sporocysts with 4 sporozoites. A polar body and a prominent oocyst residuum were present in the oocysts, but no micropyle, sporocyst residuum, or Stieda bodies were detected. Analysis of the 18S rRNA gene sequence put the parasite in the Sarcocystidae. The parasite is closely related to Besnoitia, Hammondia, Neospora, and Toxoplasma. Ultrastructural features, such as the presence of an apical complex in merozoites, support the identification of a coccidian. A new genus and species, Nephroisospora eptesicii, is proposed for this unusual coccidian in which the entire cycle is completed in the kidney of a single host; it has a membrane-like oocyst wall, sporogony occurs in the host rather than in the abiotic environment, and the positioning of the parasite by nucleic acid sequence indicates it to be closely allied to Sarcocystis and Besnoitia.