Association Between Social Vulnerability and SARS-CoV-2 Seroprevalence in Specimens Collected From Commercial Laboratories, United States, September 2021-February 2022.

OBJECTIVE: We conducted a national US study of SARS-CoV-2 seroprevalence by Social Vulnerability Index (SVI) that included pediatric data and compared the Delta and Omicron periods during the COVID-19 pandemic. The objective of the current study was to assess the association between SVI and seroprevalence of infection-induced SARS-CoV-2 antibodies by period (Delta vs Omicron) and age group. METHODS: We used results of infection-induced SARS-CoV-2 antibody assays of clinical sera specimens (N = 406 469) from 50 US states from September 2021 through February 2022 to estimate seroprevalence overall and by county SVI tercile. Bivariate analyses and multilevel logistic regression models assessed the association of seropositivity with SVI and its themes by age group (0-17, ≥18 y) and period (Delta: September-November 2021; Omicron: December 2021-February 2022). RESULTS: Aggregate infection-induced SARS-CoV-2 antibody seroprevalence increased at all 3 SVI levels; it ranged from 25.8% to 33.5% in September 2021 and from 53.1% to 63.5% in February 2022. Of the 4 SVI themes, socioeconomic status had the strongest association with seroprevalence. During the Delta period, we found significantly more infections per reported case among people living in a county with high SVI (odds ratio [OR] = 2.76; 95% CI, 2.31-3.21) than in a county with low SVI (OR = 1.65; 95% CI, 1.33-1.97); we found no significant difference during the Omicron period. Otherwise, findings were consistent across subanalyses by age group and period. CONCLUSIONS: Among both children and adults, and during both the Delta and Omicron periods, counties with high SVI had significantly higher SARS-CoV-2 antibody seroprevalence than counties with low SVI did. These disparities reinforce SVI's value in identifying communities that need tailored prevention efforts during public health emergencies and resources to recover from their effects.

Identification of potent and reversible piperidine carboxamides that are species-selective orally active proteasome inhibitors to treat malaria.

Malaria remains a global health concern as drug resistance threatens treatment programs. We identified a piperidine carboxamide (SW042) with anti-malarial activity by phenotypic screening. Selection of SW042-resistant Plasmodium falciparum (Pf) parasites revealed point mutations in the Pf_proteasome ß5 active-site (Pfß5). A potent analog (SW584) showed efficacy in a mouse model of human malaria after oral dosing. SW584 had a low propensity to generate resistance (minimum inoculum for resistance [MIR] >109) and was synergistic with dihydroartemisinin. Pf_proteasome purification was facilitated by His8-tag introduction onto ß7. Inhibition of Pfß5 correlated with parasite killing, without inhibiting human proteasome isoforms or showing cytotoxicity. The Pf_proteasome_SW584 cryoelectron microscopy (cryo-EM) structure showed that SW584 bound non-covalently distal from the catalytic threonine, in an unexplored pocket at the ß5/ß6/ß3 subunit interface that has species differences between Pf and human proteasomes. Identification of a reversible, species selective, orally active series with low resistance propensity provides a path for drugging this essential target.