Evaluation of the Abbott BinaxNOW COVID-19 Test Ag Card for rapid detection of SARS-CoV-2 infection by a local public health district with a rural population.

SARS-CoV-2 RT-PCR, the gold standard for diagnostic testing, may not be readily available or logistically applicable for routine COVID-19 testing in many rural communities in the United States. In this validation study, we compared the BinaxNOW™ COVID-19 Test Ag Card with SARS-CoV-2 RT-PCR in 214 participants who sought COVID-19 testing from a local public health district in Idaho, USA. The median age of participants was 35 and 82.7% were symptomatic. Thirty-seven participants (17.3%) had positive RT-PCR results. Results between the two tests were 94.4% concordant. The sensitivity of the BinaxNOW™ COVID-19 Test Ag Card was 67.6% (95% CI: 50.2-81.9%), and the specificity was 100.0% (95% CI: 97.9-100.0%). The positive predictive value (PPV) for the BinaxNOW™ COVID-19 Test Ag Card was 100.0% (95% CI: 86.2-100.0%), and the negative predictive value (NPV) was 93.6% (95% CI: 89.1-96.6%). Although the sensitivity of BinaxNOW™ COVID-19 Test Ag Card was lower than RT-PCR, rapid results and high specificity support its use for early detection of COVID-19, especially in settings where SARS-CoV-2 RT-PCR testing is not readily available. Rapid antigen tests, such as the BinaxNOW™ COVID-19 Test Ag Card, may be a more convenient tool in quickly identifying and preventing COVID-19 transmission, especially in rural settings.

Burrowing Owls, Pulex irritans, and Plague.

Western Burrowing Owls (Athene cunicularia hypugaea) are small, ground-dwelling owls of western North America that frequent prairie dog (Cynomys spp.) towns and other grasslands. Because they rely on rodent prey and occupy burrows once or concurrently inhabited by fossorial mammals, the owls often harbor fleas. We examined the potential role of fleas found on burrowing owls in plague dynamics by evaluating prevalence of Yersinia pestis in fleas collected from burrowing owls and in owl blood. During 2012-2013, fleas and blood were collected from burrowing owls in portions of five states with endemic plague-Idaho, Oregon, Washington, Colorado, and South Dakota. Fleas were enumerated, taxonomically identified, pooled by nest, and assayed for Y. pestis using culturing and molecular (PCR) approaches. Owl blood underwent serological analysis for plague antibodies and nested PCR for detection of Y. pestis. Of more than 4750 fleas collected from owls, Pulex irritans, a known plague vector in portions of its range, comprised more than 99.4%. However, diagnostic tests for Y. pestis of flea pools (culturing and PCR) and owl blood (PCR and serology) were negative. Thus, even though fleas were prevalent on burrowing owls and the potential for a relationship with burrowing owls as a phoretic host of infected fleas exists, we found no evidence of Y. pestis in sampled fleas or in owls that harbored them. We suggest that studies similar to those reported here during plague epizootics will be especially useful for confirming these results.

Bacterial diversity within the planktonic community of an artesian water supply.

Culture and molecular methods were used to describe the planktonic bacterial diversity of an artesian water supply in rural Latah County, Idaho, within the drainage of a small perennial stream, Thorn Creek. The surrounding depth to groundwater at this location is thought to be significant (>100 m), and this transitional zone (basalt-granite) of the Palouse aquifer system is little studied. The water produced by this artesian source is consistent even in years of drought and is of high quality, both mineralogically and microbiologically. A culture-based analysis using 30 media types and four incubation temperatures demonstrated that several metabolic types were present in the water. 16S rRNA gene fragments amplified from the DNA of pooled cultured cells and from the DNA extracted from 1 L of the source water were compared using denaturing gradient gel electrophoresis. The results indicated that the two DNA samples did not have similar 16S rRNA gene compositions and that several uncultured phyla were present in the community DNA sample. These results indicated that large-scale culturing did not accurately represent the structure planktonic community. 16S rRNA gene sequences from 17 different genera were obtained from the community DNA sample; the most abundant were similar to Rhodoferax, Rhodobacter, and Polaromonas species. Sequences related to the Proteo bacteria, Bacteroidetes/Chlorobi, Firmicutes, and Acidobacterium/Fibrobacter divisions were also detected.