Trends in disparities in COVID hospitalizations among community-dwelling residents of two counties in Connecticut, before and after vaccine introduction, March 2020-September 2021.

BACKGROUND: Prior to the introduction of vaccines, COVID-19 hospitalizations of non-institutionalized persons in Connecticut disproportionately affected communities of color and individuals of low socioeconomic status (SES). Whether the magnitude of these disparities changed 7-9 months after vaccine rollout during the Delta wave is not well documented. METHODS: All initially hospitalized patients with laboratory-confirmed COVID-19 during July-September 2021 were obtained from the Connecticut COVID-19-Associated Hospitalization Surveillance Network database, including patients' geocoded residential addresses. Census tract measures of poverty and crowding were determined by linking geocoded residential addresses to the 2014-2018 American Community Survey. Age-adjusted incidence and relative rates of COVID-19 hospitalization were calculated and compared with those from July to December 2020. Vaccination levels by age and race/ethnicity at the beginning and end of the study period were obtained from Connecticut's COVID vaccine registry, and age-adjusted average values were determined. RESULTS: There were 708 COVID-19 hospitalizations among community residents of the two counties, July-September 2021. Age-adjusted incidence was the highest among non-Hispanic Blacks and Hispanic/Latinx compared with non-Hispanic Whites (RR 4.10 [95% CI 3.41-4.94] and 3.47 [95% CI 2.89-4.16]). Although RR decreased significantly among Hispanic/Latinx and among the lowest SES groups, it increased among non-Hispanic Blacks (from RR 3.2 [95% CI 2.83-3.32] to RR 4.10). Average age-adjusted vaccination rates among those ≥12 years were the lowest among non-Hispanic Blacks compared with Hispanic/Latinx and non-Hispanic Whites (50.6% vs. 64.7% and 66.6%). CONCLUSIONS: Although racial/ethnic and SES disparities in COVID-19 hospitalization have mostly decreased over time, disparities among non-Hispanic Blacks increased, possibly due to differences in vaccination rates.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Outbreak at a College With High Coronavirus Disease 2019 (COVID-19) Vaccination Coverage-Connecticut, August 2021-September 2021.

BACKGROUND: During August 2021-September 2021, a Connecticut college experienced a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta variant outbreak despite high (99%) vaccination coverage, indoor masking policies, and twice-weekly testing. The Connecticut Department of Public Health investigated characteristics associated with infection and phylogenetic relationships among cases. METHODS: A case was a SARS-CoV-2 infection diagnosed by a viral test during August 2021-September 2021 in a student. College staff provided enrollment and case information. An anonymous online student survey collected demographics, SARS-CoV-2 case and vaccination history, and activities preceding the outbreak. Multivariate logistic regression identified characteristics associated with infection. Phylogenetic analyses compared 115 student viral genome sequences with contemporaneous community genomes. RESULTS: Overall, 199 of 1788 students (11%) had laboratory-confirmed SARS-CoV-2 infection; most were fully vaccinated (194 of 199, 97%). Attack rates were highest among sophomores (72 of 414, 17%) and unvaccinated students (5 of 18, 28%). Attending in-person classes with an infectious student was not associated with infection (adjusted odds ratio [aOR], 1.0; 95% confidence interval [CI], .5-2.2). Compared with uninfected students, infected students were more likely to be sophomores (aOR, 3.3; 95% CI, 1.1-10.7), attend social gatherings before the outbreak (aOR, 2.8; 95% CI, 1.3-6.4), and complete a vaccine series ≥180 days prior (aOR, 5.5; 95% CI, 1.8-16.2). Phylogenetic analyses suggested a common viral source for most cases. CONCLUSIONS: SARS-CoV-2 infection in this highly vaccinated college population was associated with unmasked off-campus social gatherings, not in-person classes. Students should stay up to date on vaccination to reduce infection.