Harmonization of Newborn Screening Results for Pompe Disease and Mucopolysaccharidosis Type I.

In newborn screening, false-negative results can be disastrous, leading to disability and death, while false-positive results contribute to parental anxiety and unnecessary follow-ups. Cutoffs are set conservatively to prevent missed cases for Pompe and MPS I, resulting in increased falsepositive results and lower positive predictive values. Harmonization has been proposed as a way to minimize false-negative and false-positive results and correct for method differences, so we harmonized enzyme activities for Pompe and MPS I across laboratories and testing methods (Tandem Mass Spectrometry (MS/MS) or Digital Microfluidics (DMF)). Participating states analyzed proofof- concept calibrators, blanks, and contrived specimens and reported enzyme activities, cutoffs, and other testing parameters to Tennessee. Regression and multiples of the median were used to harmonize the data. We observed varied cutoffs and results. Six of seven MS/MS labs reported enzyme activities for one specimen for MPS I marginally above their respective cutoffs with results classified as negative, whereas all DMF labs reported this specimen's enzyme activity below their respective cutoffs with results classified as positive. Reasonable agreement in enzyme activities and cutoffs was achieved with harmonization; however, harmonization does not change how a value would be reported as this is dependent on the placement of cutoffs.

Prevalence of IgG antibodies against the severe acute respiratory syndrome coronavirus-2 among healthcare workers in Tennessee during May and June, 2020.

SARS-CoV-2 seroprevalence was low (<1%) in this large population of healthcare workers (HCWs) across the state of Tennessee (n=11,787) in May-June 2020. Among those with PCR results, 81.5% of PCR and antibody test results were concordant. SARS-CoV-2 seroprevalence was higher among HCWs working in high-community-transmission regions and among younger workers. IMPORTANCE: These results may be seen as a baseline assessment of SARS-CoV-2 seroprevalence among HCWs in the American South during a period of growth, but not yet saturation, of infections among susceptible populations. In fact, this period of May-June 2020 was marked by the extension of renewed and sustained community-wide transmission after mandatory quarantine periods expired in several more populous regions of Tennessee. Where community transmission remains low, HCWs may still be able to effectively mitigate SARS-CoV-2 transmission, preserving resources for populations at high risk of severe disease, and these sorts of data help highlight such strategies.

West Nile virus infection in free-ranging squirrels in Illinois.

West Nile virus (WNV) infection was diagnosed in 13 gray squirrels (Sciurus carolinensis) and 3 fox squirrels (Sciurus niger) that were observed with neurologic signs before death or found dead. All 16 had gliosis throughout all sections of the brain. Most had lymphoplasmacytic encephalitis or meningoencephalitis, many with admixed neutrophils. Neuronal necrosis and neuronophagia were also prominent features. West Nile virus antigen was demonstrated in the brain, spleen, heart or kidney in 10 of 13 gray squirrels and 3 of 3 fox squirrels by immunohistochemistry. Nucleic acid amplification tests (NAATs) confirmed the presence of WNV in the brain or spinal cord of 10/10 gray squirrels and 1/3 fox squirrels tested. Viral levels were quantified in various tissues of selected gray squirrels, and titers were highest in spleen and brain, with no virus detected in serum. This is the first description of lesions associated with WNV infection in gray and fox squirrels.