The Advisory Committee on Immunization Practices (ACIP) recommended that dengue pre-vaccination screening tests for Dengvaxia administration have at least 98% specificity and 75% sensitivity. This study evaluates the performance of commercial anti-DENV IgG tests to identify tests that could be used for pre-vaccination screening. First, for seven tests, we evaluated sensitivity and specificity in early convalescent dengue virus (DENV) infection, using 44 samples collected 7-30 days after symptom onset and confirmed by RT-PCR. Next, for the five best-performing tests and two additional tests (with and without an external test reader) that became available later, we evaluated performance to detect past dengue infection among a panel of 44 specimens collected in 2018-2019 from healthy 9- to 16-year-old children from Puerto Rico. Finally, a full-scale evaluation was done with the four best-performing tests using 400 specimens from the same population. We used virus focus reduction neutralization test and an in-house DENV IgG ELISA as reference standards. Of seven tests, five showed ≥75% sensitivity in detecting anti-DENV IgG in early convalescent specimens with low cross-reactivity to the Zika virus. For the detection of previous DENV infections, the tests with the highest performance were the Euroimmun NS1 IgG ELISA (sensitivity 84.5%, specificity 97.1%) and CTK Dengue IgG rapid test R0065C with the test reader (sensitivity 76.2% specificity 98.1%). There are IgG tests available that can be used to accurately classify individuals with previous DENV infection as eligible for dengue vaccination to support safe vaccine implementation. IMPORTANCE: The Advisory Committee on Immunization Practices (ACIP) has set forth recommendations that dengue pre-vaccination screening tests must exhibit at least 98% specificity and 75% sensitivity. Our research rigorously assesses the performance of various commercial tests against these benchmarks using well-characterized specimens from Puerto Rico. The findings from our study are particularly relevant given FDA approval and ACIP recommendation of Sanofi Pasteur's Dengvaxia vaccine, highlighting the need for accurate pre-vaccination screening tools.

BACKGROUND: Structural racism and pandemic-related stress from the COVID-19 pandemic may increase risk of adverse birth outcomes. OBJECTIVE: Our objective was to examine associations between neighborhood measures of structural racism and pandemic stress with three outcomes: SARS-CoV-2 infection, preterm birth (PTB) and delivering a newborn small-for-gestational-age (SGA). Our secondary objective was to investigate the joint associations of SARS-CoV-2 infection during pregnancy and neighborhood measures on PTB and SGA. STUDY DESIGN: We analyzed data for 967 patients from a prospective cohort of pregnant persons in New York City, comprised of 367 White persons (38%), 169 Black persons (17%), 293 Latina persons (30%), 87 Asian persons (9%), 41 persons of unknown race-ethnicity (4%), and 10 of unknown race-ethnicity (1%). We evaluated structural racism (social/built structural disadvantage, racial-economic segregation) and pandemic-related stress (community COVID-19 mortality, community unemployment rate increase) in quartiles by zip code. SARS-CoV-2 serologic enzyme-linked immunosorbent assay was performed on blood samples from pregnant persons. We ascertained preterm birth (PTB) and small-for-gestational age (SGA) from an electronic medical record database. We used log-binomial regression with robust standard error for clustering by zip code to estimate associations of each neighborhood measure separately with three outcomes: SARS-CoV-2 infection, PTB, and SGA. Covariates included maternal age, parity, insurance status, and BMI. Models with PTB and SGA as the dependent variables additionally adjusted for SARS-CoV-2 infection. RESULTS: 193 (20%) persons were SARS-CoV-2 seropositive, and the overall risk of PTB and SGA were 8.4% and 9.8%, respectively. Among birthing persons in neighborhoods in the highest quartile of structural disadvantage (n=190), 94% were non-White, 50% had public insurance, 41% were obese, 32% were seropositive, 11% delivered preterm, and 12% delivered an infant SGA. Among birthing persons in neighborhoods in the lowest quartile of structural disadvantage (n=360), 39% were non-White, 17% had public insurance, 15% were obese, 9% were seropositive, 6% delivered preterm, and 10% delivered an infant SGA. In adjusted analyses structural racism measures and community unemployment were associated with both SARS-CoV-2 infection and PTB, but not SGA. High vs. low structural disadvantage was associated with an adjusted relative risk (aRR) of 2.6 for infection (95% Confidence Interval (CI)=1.7, 3.9) and 1.7 for PTB (95%CI=1.0, 2.9); high vs. low racial-economic segregation was associated with aRR of 1.9 (95% CI=1.3, 2.8) for infection and 2.0 (95%CI=1.3, 3.2) for PTB; high vs. low community unemployment increase was associated with aRR of 1.7 (95% CI=1.2, 1.5) for infection and 1.6 (95%CI=1.0, 2.8) for PTB. COVID-19 mortality rate was associated with SARS-CoV-2 infection, but not PTB or SGA. SARS-CoV-2 infection was not independently associated with birth outcomes. We found no interaction between SARS-CoV-2 infection and neighborhood measures on PTB or SGA. CONCLUSIONS: Neighborhood measures of structural racism were associated with both SARS-CoV-2 infection and PTB, but these associations were independent and did not have a synergistic effect. Community unemployment rate increases were also associated with an increased risk of PTB independently of SARS-CoV-2 infection. Mitigating these factors might reduce the impact of the pandemic on pregnant people.

Selenium represents an essential trace nutrient that is necessary for biological functions. Deficiencies can induce disease, but excess can induce toxicity. Selenium deficiency is a major concern in underdeveloped countries, while also posing as a toxic pollutant in waterways surrounding landfills, agricultural areas, and fossil fuel production sites. We examined the microbiome of selenomethionine (SeMet) fed American alligators (Alligator mississippiensis) at the beginning and end of a 7-week exposure experiment. Alligators were randomly divided into three groups: control and 1000 or 2000 ppm SeMet. DNA from before exposure (oral and cloaca swabs) and post-exposure (oral, cloaca, small & large intestines) sampling were extracted and amplified for bacterial 16 s rRNA. While treatment did not seem to have much effect, we observed a predominance of Fusobacteriaceae and Porpyromonodaceae across all tissue types. Cetobacterium and Clostridium are the most abundant genera as potential indicators of the aquatic and carrion feeding lifestyle of alligators.

Paraquat (PQ) is an herbicide used in many countries, including the USA. It is also implicated as a risk factor for sporadic Parkinson's disease (sPD), especially in those living in agricultural areas and drinking well water. Studies linking PQ to sPD are not consistent however and there appears to be inter-individual differential susceptibility. One likely reason is genetically based differential susceptibility to paraquat neurotoxicity in sub-populations. To address this issue, we tested the effects of paraquat in a genetic reference population of mice (the BXD recombinant inbred strain family). In our earlier work, we showed that in genetically susceptible mice, paraquat increases iron in the ventral midbrain, the area containing the substantia nigra. Our hypothesis is that genetic variability contributes to diverse PQ-related susceptibility and iron concentration. To test this hypothesis, we treated male mice from 28-39 BXD strains plus the parental strains with one of 3 doses of paraquat, 1, 5 and 10 mg/kg three times on a weekly basis. At the end of the treatment period, we analyzed the ventral midbrain for concentrations of iron, copper, and zinc, also we measured the concentration of paraquat in cerebellum, and proinflammatory cytokines in serum and cerebellum. The effect on paraquat treated mice with 5 mg/kg and principal component analysis of iron showed suggestive QTL on chromosome 5. Overall, our results suggest that gene Prkag2 and related networks may serve as potential targets against paraquat toxicity and demonstrate the utility of genetically diverse mouse models for the study of complex human toxicity.

BACKGROUND: Dengue is an important arboviral disease with about 100 million dengue cases per year, of which, ~5% result in severe disease. Clinical differentiation of dengue from other acute febrile illnesses (AFI) is difficult, and diagnostic blood tests are costly. We evaluated the utility of anti-DENV IgM in urine to identify dengue cases among AFI patients enrolled in a clinical study. METHODS: Between May 2012-March 2013, 1538 study participants with fever for </=7 days were enrolled, a medical history was obtained, and serum and urine specimens were collected. Serum was tested for DENV RNA and anti-DENV IgM. Urine was tested for anti-DENV IgM, and its sensitivity and specificity to detect sera laboratory-positive dengue cases were calculated. We evaluated if urine anti-DENV IgM positivity early (</=5 days post-illness onset [DPO]) and late (6-14 DPO) in the clinical course was associated with dengue severity. RESULTS: Urine anti-DENV IgM sensitivity and specificity were 47.4% and 98.5%, respectively, when compared with serum anti-DENV IgM ELISA results, and 29.7% and 91.1% when compared with serum rRT-PCR results. There was no correlation between urine anti-DENV IgM positivity and patient sex or pre-existing chronic disease. Early in the clinical course, a significantly higher proportion of those who developed dengue with warning signs had anti-DENV IgM in their urine when compared to those without warning signs (20.4% vs. 4.3%). There was no difference in the proportion with urine anti-DENV IgM positivity between severity groups late in the clinical course. CONCLUSION: While detection of urine anti-DENV IgM lacked adequate diagnostic sensitivity, it is a highly specific marker for laboratory-positive dengue, and its presence early in the clinical course may distinguish those with more severe disease. Further assessment of urine anti-DENV IgM by DPO is warranted to determine its utility as an early diagnostic (and possibly prognostic) marker for dengue.

BACKGROUND: Anti-dengue virus (DENV) immunoglobulin M (IgM) seroconversion has been the reference standard for dengue diagnosis. However, paired specimens are rarely obtained, and the interval for this testing negates its usefulness in guiding clinical case management. The presence of DENV viremia and appearance of IgM during the febrile phase of dengue provides the framework for dengue laboratory diagnosis by using a single serum specimen. METHODS: Archived paired serum specimens (n = 1234) from patients with laboratory-confirmed dengue from 2005 through 2011 were used to determine the diagnostic performance of real-time reverse transcription polymerase chain reaction (RT-PCR), for detection of DENV serotypes 1-4, and enzyme-linked immunosorbent assays (ELISAs), for detection of DENV nonstructural protein 1 (NS1) antigen and anti-DENV IgM. RESULTS: During 1-3 days after illness onset, real-time RT-PCR and NS1 antigen testing detected 82%-69% and 90%-84% of cases, respectively, as viremia levels declined, while anti-DENV IgM ELISA detected 5%-41% of cases as antibody appeared. Over the 10-day period of the febrile phase of dengue, the cumulative effect of using these 3 types of tests in a diagnostic algorithm confirmed ≥90% of dengue cases. CONCLUSIONS: The use of molecular or NS1 antigen tests to detect DENV and one to detect anti-DENV IgM in a single serum specimen collected during the first 10 days of illness accurately identified ≥90% of dengue primary and secondary cases.

West Nile virus (WNV) outbreaks in North America have been characterized by substantial die-offs of American crows (Corvus brachyrhynchos). In contrast, a low incidence of bird deaths has been observed during WNV epidemic activity in Europe. To examine the susceptibility of the western European counterpart of American crows, we inoculated carrion crows (Corvus corone) with WNV strains isolated in Greece (Gr-10), Italy (FIN and Ita09), and Hungary (578/10) and with the highly virulent North American genotype strain (NY99). We also inoculated American crows with a selection of these strains to examine the strains' virulence in a highly susceptible bird species. Infection with all strains, except WNV FIN, resulted in high rates of death and high-level viremia in both bird species and virus dissemination to several organs. These results suggest that carrion crows are highly susceptible to WNV and may potentially be useful as part of dead bird surveillance for early warning of WNV activity in Europe.

BACKGROUND: Early detection and control of vaccine-derived poliovirus (VDPV) emergences are essential to secure the gains of polio eradication. METHODS: Serial sewage samples were collected in 4 towns of Mexico before, throughout, and after the May 2010 oral poliovirus vaccine (OPV) mass immunization campaign. Isolation and molecular analysis of polioviruses from sewage specimens monitored the duration of vaccine-related strains in the environment and emergence of vaccine-derived polioviruses in a population partially immunized with inactivated poliovirus vaccine (IPV). RESULTS: Sabin strains were identified up to 5-8 weeks after the campaign in all towns; in Aguascalientes, 1 Sabin 3 was isolated 16 weeks after the campaign, following 7 weeks with no Sabin strains detected. In Tuxtla Gutierrez, type 2 VDPV was isolated from 4 samples collected before and during the campaign, and type 1 VDPV from 1 sample collected 19 weeks afterward. During 2009-2010, coverage in 4 OPV campaigns conducted averaged only 57% and surveillance for acute flaccid paralysis (AFP) was suboptimal (AFP rate <1 per 100 000 population <15 years of age) in Tuxtla Gutierrez. CONCLUSIONS: VDPVs may emerge and spread in settings with inadequate coverage with IPV/OPV vaccination. Environmental surveillance can facilitate early detection in these settings.

A commercial anti-dengue virus (DENV) indirect IgG enzyme-linked immunosorbent assay (ELISA) for serological diagnosis was evaluated for its utility in determining previous DENV exposure in US travelers. The Boston Area Travel Medicine Network clinics used Focus Diagnostics anti-DENV IgG ELISA to measure anti-DENV IgG antibodies in 591 pre-travel specimens from US residents who had traveled to dengue endemic countries. When using the manufacturer's index cut-off value for this ELISA, false-positive results were observed that overestimated the perceived past DENV exposure in US travelers. Validation of 121 of these anti-DENV IgG results by plaque reduction neutralization test (PRNT) was used for receiver operator characteristics (ROC) curve optimization of the index cut-off value from 1 to 3.0, improving the specificity of the anti-DENV IgG ELISA from 24% to 95.7%. Additionally, previous vaccination with yellow fever virus contributed to 52.8% of the false positive rate in the anti-DENV IgG ELISA results. Optimization of the cut-off value of the anti-DENV IgG ELISA provided better interpretation and confidence in the results and eliminated the need for confirmation by PRNT. The travel history of US travelers was also useful for categorizing these travelers in groups for analysis of previous DENV exposure.

Directors of all major BioSafety Level 4 (BSL-4) laboratories in the United States met in 2008 to review the current status of biocontainment laboratory operations and to discuss the potential impact of a proposed 2-person security rule on maximum-containment laboratory operations. Special attention was paid to the value and risks that would result from a requirement that 2 persons be physically present in the laboratory at all times. A consensus emerged indicating that a video monitoring system represents a more efficient, economical standard; provides greater assurance that pathogens are properly manipulated; and offers an increased margin of employee safety and institutional security. The 2-person security rule (1 to work and 1 to observe) may decrease compliance with dual responsibilities of safety and security by placing undue pressure on the person being observed to quickly finish the work, and by placing the observer in the containment environment unnecessarily.