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OBJECTIVES: As the world transitions into a new era of the COVID-19 pandemic in which vaccines become available, there is an increasing demand for rapid reliable serological testing to identify individuals with levels of immunity considered protective by infection or vaccination. METHODS: We used 34 SARS-CoV-2 samples to perform a rapid surrogate virus neutralisation test (sVNT), applicable to many laboratories as it circumvents the need for biosafety level-3 containment. We correlated results from the sVNT with five additional commonly used SARS-CoV-2 serology techniques: the microneutralisation test (MNT), in-house ELISAs, commercial Euroimmun- and Wantai-based ELISAs (RBD, spike and nucleoprotein; IgG, IgA and IgM), antigen-binding avidity, and high-throughput multiplex analyses to profile isotype, subclass and Fc effector binding potential. We correlated antibody levels with antibody-secreting cell (ASC) and circulatory T follicular helper (cTfh) cell numbers. RESULTS: Antibody data obtained with commercial ELISAs closely reflected results using in-house ELISAs against RBD and spike. A correlation matrix across ten measured ELISA parameters revealed positive correlations for all factors. The frequency of inhibition by rapid sVNT strongly correlated with spike-specific IgG and IgA titres detected by both commercial and in-house ELISAs, and MNT titres. Multiplex analyses revealed strongest correlations between IgG, IgG1, FcR and C1q specific to spike and RBD. Acute cTfh-type 1 cell numbers correlated with spike and RBD-specific IgG antibodies measured by ELISAs and sVNT. CONCLUSION: Our comprehensive analyses provide important insights into SARS-CoV-2 humoral immunity across distinct serology assays and their applicability for specific research and/or diagnostic questions to assess SARS-CoV-2-specific humoral responses.

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Compared to adults, children with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have mild or asymptomatic infection, but the underlying immunological differences remain unclear. We describe clinical features, virology, longitudinal cellular and cytokine immune profile, SARS-CoV-2-specific serology and salivary antibody responses in a family of two parents with PCR-confirmed symptomatic SARS-CoV-2 infection and their three children, who were repeatedly SARS-CoV-2 PCR negative. Cellular immune profiles and cytokine responses of all children were similar to their parents at all timepoints. All family members had salivary anti-SARS-CoV-2 antibodies detected, predominantly IgA, that coincided with symptom resolution in 3 of 4 symptomatic members. Plasma from both parents and one child had IgG antibody detected against the S1 protein and virus neutralising activity ranging from just detectable to robust titers. Using a systems serology approach, we show that all family members demonstrated higher levels of SARS-CoV-2-specific antibody features than healthy controls. These data indicate that children can mount an immune response to SARS-CoV-2 without virological evidence of infection. This raises the possibility that despite chronic exposure, immunity in children prevents establishment of SARS-CoV-2 infection. Relying on routine virological and serological testing may therefore not identify exposed children, with implications for epidemiological and clinical studies across the life-span.

After more than half a century of unrealized potential, India is now emerging as an important state in the global balance of power. In the years ahead, India will have an opportunity to shape the outcomes on some of the most critical issues of the twenty-first century: the construction of Asian stability, globalization, economic prosperity, cultural vibrancy, neutralization of extremist ideologies, terrorism and fundamentalism, and upholding democracy. Given the magnitude of the global security challenges, the United States needs a strong and competent partner in the Indian sub-continent. With the signing of the India-US nuclear pact, a major milestone has been reached in the relations between the two countries. However, the past record of India-US relations has not been encouraging and although it has reached an all time high now, there is a need to sustain, strengthen, and further this relationship. This study will focus on the various areas which provide the opportunities for building confidence, progressing in mutually beneficial fields, and promoting peace and stability as natural allies in a turbulent world., USAWC Strategy Research Project

Since the consolidation of several civil engineering career fields into one generalized Minuteman facility maintenance specialty there has been debate over whether it resulted in more effective maintenance and better trained technicians, or whether personnel proficiency and hardware conditions have deteriorated. To study this question historical data from 3901st Strategic Missile Evaluation Squadron reports was analyzed in terms of personnel proficiency ratings and diesel pass rates. Additionally, as survey of the technicians was conducted to determine their perceptions of their performance. Results indicate personnel proficiency and diesel pass rates have declined since the consolidation of the specialties, and corrective action will be complicated by technicians perceptions of their adequate job proficiency. Recommendations include dividing the technicians into specialized maintenance areas, modifying training programs to accommodate this specialization, increasing the time required for upgrade to the five skill level, emphasizing adequate feedback at all levels of supervision, and improving the information maintained in evaluation archival records. (Author)