Comparison of Levels of Nasal, Salivary, and Plasma Antibody to Severe Acute Respiratory Syndrome Coronavirus 2 During Natural Infection and After Vaccination.

BACKGROUND: Most studies of immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) measure antibody or cellular responses in blood; however, the virus infects mucosal surfaces in the nose and conjunctivae and infectious virus is rarely if ever present in the blood. METHODS: We used luciferase immunoprecipitation assays to measure SARS-CoV-2 antibody levels in the plasma, nose, and saliva of infected persons and vaccine recipients. These assays measure antibody that can precipitate the SAR-CoV-2 spike and nucleocapsid proteins. RESULTS: Levels of plasma anti-spike antibody declined less rapidly than levels of anti-nucleocapsid antibody in infected persons. SARS-CoV-2 anti-spike antibody levels in the nose declined more rapidly than antibody levels in the blood after vaccination of infected persons. Vaccination of previously infected persons boosted anti-spike antibody in plasma more than in the nose or saliva. Nasal and saliva anti-spike antibody levels were significantly correlated with plasma antibody in infected persons who had not been vaccinated and after vaccination of uninfected persons. CONCLUSIONS: Persistently elevated SARS-CoV-2 antibody in plasma may not indicate persistence of antibody at mucosal sites such as the nose. The strong correlation of SARS-CoV-2 antibody in the nose and saliva with that in the blood suggests that mucosal antibodies are derived primarily from transudation from the blood rather than local production. While SARS-CoV-2 vaccine given peripherally boosted mucosal immune responses in infected persons, the increase in antibody titers was higher in plasma than at mucosal sites. Taken together, these observations indicate the need for development of mucosal vaccines to induce potent immune responses at sites where SARS-CoV-2 infection occurs. CLINICAL TRIALS REGISTRATION: NCT01306084.

Medical Mistrust, Perceived Discrimination, and Race: a Longitudinal Analysis of Predictors of COVID-19 Vaccine Hesitancy in US Adults.

The current manuscript has two aims. First, we examined whether race and ethnicity, perceived discrimination, medical mistrust, and other demographic factors were predictors of COVID-19 vaccine hesitancy and vaccine behavior. Second, we sought to assess whether medical mistrust and perceived discrimination mediate the relationship between race and ethnicity and vaccine behavior. Specifically, we hypothesized that individuals of color had increased COVID-19 vaccine hesitancy as compared to White individuals and perceived discrimination and medical mistrust mediated this relationship. Results revealed that when accounting for sociodemographic characteristics and COVID-19-related variables those with greater medical mistrust were more likely to have vaccine hesitancy. Additionally, after accounting for medical mistrust, Black non-Hispanic/Black Hispanic/White Hispanic individuals had lower odds of having the COVID-19 vaccine compared to White non-Hispanic individuals. Furthermore, combined perceived discrimination and medical mistrust indirectly mediated the relationship between race and ethnicity and having the COVID-19 vaccine. The findings of this study indicate the need for public health efforts to address sentiments of medical mistrust and experiences of perceived discrimination when combating COVID-19 vaccine hesitancy, especially within communities of color.