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Introduction The recently emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus that causes coronavirus disease 2019 (COVID-19) disease, has spread globally and is now responsible for massive [...], The newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) highlights the urgent need for assays that detect protective levels of neutralizing antibodies. We studied the relationship among anti-spike ectodomain (anti-ECD), antireceptor-binding domain (anti-RBD) IgG titers, and SARS-CoV-2 virus neutralization (VN) titers generated by 2 in vitro assays using convalescent plasma samples from 68 patients with COVID-19. We report a strong positive correlation between both plasma anti-RBD and anti-ECD IgG titers and in vitro VN titers. The probability of a VN titer of [greater than or equal to] 160, the FDA-recommended level for convalescent plasma used for COVID-19 treatment, was [greater than or equal to] 80% when anti-RBD or anti-ECD titers were [greater than or equal to] 1:1350. Of all donors, 37% lacked VN titers of [greater than or equal to] 160. Dyspnea, hospitalization, and disease severity were significantly associated with higher VN titer. Frequent donation of convalescent plasma did not significantly decrease VN or IgG titers. Analysis of 2814 asymptomatic adults found 73 individuals with anti-ECD IgG titers of [greater than or equal to] 1:50 and strong positive correlation with anti-RBD and VN titers. Fourteen of these individuals had VN titers of [greater than or equal to] 1:160, and all of them had anti-RBD titers of [greater than or equal to] 1:1350. We conclude that anti-RBD or anti-ECD IgG titers can serve as a surrogate for VN titers to identify suitable plasma donors. Plasma anti-RBD or anti-ECD titers of [greater than or equal to] 1:1350 may provide critical information about protection against COVID-19 disease.

Outbreaks and spread of infectious diseases are often associated with seasonality and environmental changes, including global warming. Free‐living stages of soil‐transmitted helminths are highly susceptible to climatic drivers; however, how multiple climatic variables affect helminth species, and the long‐term consequences of these interactions, is poorly understood. We used experiments on nine trichostrongylid species of herbivores to develop a temperature‐ and humidity‐dependent model of infection hazard, which was then implemented at the European scale under climate change scenarios. Intestinal and stomach helminths exhibited contrasting climatic responses, with the former group strongly affected by temperature while the latter primarily impacted by humidity. Among the demographic traits, larval survival heavily modulated the infection hazard. According to the specific climatic responses of the two groups, climate change is expected to generate differences in the seasonal and spatial shifts of the infection hazard and group co‐circulation. In the future, an intensification of these trends could create new opportunities for species range expansion and co‐occurrence at European central‐northern latitudes. [ABSTRACT FROM AUTHOR]

Simple Summary: The Manyara region is amongst the tuberculosis hot spot regions in Tanzania; both pulmonary and extra-pulmonary cases have been reported, which raises questions on risk factors of the disease and the Mycobacteria species circulating in the area. A questionnaire was administered to identify risk factors of the disease. Furthermore, pulmonary and extra-pulmonary samples were collected from participants and cultured, and organisms from positive cultures were subjected to molecular speciation using PCR to identify MTBC species. The study found a low awareness of both human TB, animal TB, and zoonotic TB among participants. All specimens, pulmonary or extrapulmonary, that were positive by culture were typed as M. tuberculosis sensu stricto. Effective TB disease educational programs should be implemented to overcome the problem. Tuberculosis (TB) results from infection with members of the Mycobacterium tuberculosis complex (MTBC) and represents a major global public health concern. We here sought to assess the perceptions of human and animal TB and the prevalence of circulating MTBCs lineages and associated risk factors through a cross-sectional survey of 335 individuals presenting with symptoms of pulmonary or extrapulmonary TB in the Manyara region of Tanzania. After the enrollment of participants, a questionnaire survey was conducted, samples were collected for bacterial culture, and real-time multiplex PCR was performed to differentiate amongst primary animal and human MTBC lineages. The results show poor TB awareness: 31.6% of the participants were not aware of human TB; 82.4% were unaware of animal TB and 95.2% lacked awareness of zoonotic TB (zTB) transmission. A total of 18 recovered specimens (5%; 95% CI: 3–8%) were positive by culture, all of which were typed as M. tuberculosis sensu stricto using a lineage-specific PCR assay. While no single risk factor was significantly associated with MTBC culture positivity, the survey revealed considerable self-reported high-risk practices for contracting zTB. Together, the results show that Manyara residents have poor knowledge of diseases caused by MTBCs and high evidence of risky practices for contracting zTB. [ABSTRACT FROM AUTHOR]

The conceptual understanding of immune‐mediated interactions between parasites is rooted in the theory of community ecology. One of the limitations of this approach is that most of the theory and empirical evidence has focused on resource or immune‐mediated competition between parasites and yet there is ample evidence of positive interactions that could be generated by immune‐mediated facilitation.We developed an immuno‐epidemiological model and applied it to long‐term data of two gastrointestinal helminths in two rabbit populations to investigate, through model testing, how immune‐mediated mechanisms of parasite regulation could explain the higher intensities of both helminths in rabbits with dual than single infections.The model framework was selected and calibrated on rabbit population A and then validated on the nearby rabbit population B to confirm the consistency of the findings and the generality of the mechanisms. Simulations suggested that the higher intensities in rabbits with dual infections could be explained by a weakened or low species‐specific IgA response and an asymmetric IgA cross‐reaction.Simulations also indicated that rabbits with dual infections shed more free‐living stages that survived for longer in the environment, implying greater transmission than stages from hosts with single infections. Temperature and humidity selectively affected the free‐living stages of the two helminths.These patterns were comparable in the two rabbit populations and support the hypothesis that immune‐mediated facilitation can contribute to greater parasite fitness and local persistence. [ABSTRACT FROM AUTHOR]

Why are cows sacred? Travel anywhere in India and they have the right of way. Travel anywhere in the eastern United States and you'll see squirrels, more than likely, as [...]

Author(s): Isabella M. Cattadori (corresponding author) [1]; Daniel T. Haydon [2]; Peter J. Hudson [1] There is circumstantial evidence that correlated climatic conditions can drive animal populations into synchronous fluctuations [...]