Application of a life table approach to assess duration of BNT162b2 vaccine-derived immunity by age using COVID-19 case surveillance data during the Omicron variant period.

BACKGROUND: SARS-CoV-2 Omicron variants have the potential to impact vaccine effectiveness and duration of vaccine-derived immunity. We analyzed U.S. multi-jurisdictional COVID-19 vaccine breakthrough surveillance data to examine potential waning of protection against SARS-CoV-2 infection for the Pfizer-BioNTech (BNT162b) primary vaccination series by age. METHODS: Weekly numbers of SARS-CoV-2 infections during January 16, 2022-May 28, 2022 were analyzed by age group from 22 U.S. jurisdictions that routinely linked COVID-19 case surveillance and immunization data. A life table approach incorporating line-listed and aggregated COVID-19 case datasets with vaccine administration and U.S. Census data was used to estimate hazard rates of SARS-CoV-2 infections, hazard rate ratios (HRR) and percent reductions in hazard rate comparing unvaccinated people to people vaccinated with a Pfizer-BioNTech primary series only, by age group and time since vaccination. RESULTS: The percent reduction in hazard rates for persons 2 weeks after vaccination with a Pfizer-BioNTech primary series compared with unvaccinated persons was lowest among children aged 5-11 years at 35.5% (95% CI: 33.3%, 37.6%) compared to the older age groups, which ranged from 68.7%-89.6%. By 19 weeks after vaccination, all age groups showed decreases in the percent reduction in the hazard rates compared with unvaccinated people; with the largest declines observed among those aged 5-11 and 12-17 years and more modest declines observed among those 18 years and older. CONCLUSIONS: The decline in vaccine protection against SARS-CoV-2 infection observed in this study is consistent with other studies and demonstrates that national case surveillance data were useful for assessing early signals in age-specific waning of vaccine protection during the initial period of SARS-CoV-2 Omicron variant predominance. The potential for waning immunity during the Omicron period emphasizes the importance of continued monitoring and consideration of optimal timing and provision of booster doses in the future.

Possible Exposures Among Mpox Patients Without Reported Male-to-Male Sexual Contact - Six U.S. Jurisdictions, November 1-December 14, 2022.

The extent to which the 2022 mpox outbreak has affected persons without a recent history of male-to-male sexual contact (MMSC) is not well understood. During November 1-December 14, 2022, CDC partnered with six jurisdictional health departments to characterize possible exposures among mpox patients aged ≥18 years who did not report MMSC during the 3 weeks preceding symptom onset. Among 52 patients included in the analysis, 14 (27%) had a known exposure to a person with mpox, including sexual activity and other close intimate contact (eight) and household contact (six). Among 38 (73%) patients with no known exposure to a person with mpox, self-reported activities before illness onset included sexual activity and other close intimate contact (17; 45%), close face-to-face contact (14; 37%), attending large social gatherings (11; 29%), and being in occupational settings involving close skin-to-skin contact (10; 26%). These findings suggest that sexual activity remains an important route of mpox exposure among patients who do not report MMSC.

Recent Incarceration Among Individuals Infected With Hepatitis A Virus During Person-to-Person Community Outbreaks, United States, 2016-2020.

OBJECTIVES: Although many people who are incarcerated have risk factors for hepatitis A virus (HAV) infection, the proportion of hepatitis A cases among people with a recent incarceration is unknown. We examined the relationship between recent incarceration and HAV infection during community-based, person-to-person outbreaks to inform public health recommendations. METHODS: The Centers for Disease Control and Prevention surveyed health departments in 33 jurisdictions reporting person-to-person HAV outbreaks during 2016-2020 on the number of outbreak-associated cases, HAV-infected people recently incarcerated, and HAV-associated hospitalizations and deaths. RESULTS: Twenty-five health departments reported 18 327 outbreak-associated hepatitis A cases during January 11, 2016-January 24, 2020. In total, 2093 (11.4%) HAV-infected people had been recently incarcerated. Of those with complete data, 1402 of 1462 (95.9%) had been held in a local jail, and 1513 of 1896 (79.8.%) disclosed hepatitis A risk factors. Eighteen jurisdictions reported incarceration timing relative to the exposure period. Of 9707 cases in these jurisdictions, 991 (10.2%) were among recently incarcerated people; 451 of 688 (65.6%) people with complete data had been incarcerated during all (n = 55) or part (n = 396) of their exposure period. CONCLUSIONS: Correctional facilities are important settings for reaching people with risk factors for HAV infection and can also be venues where transmission occurs. Providing HAV vaccination to incarcerated people, particularly people housed in jails, can be an effective component of community-wide outbreak response.

Demographic and Clinical Characteristics of Mpox in Persons Who Had Previously Received 1 Dose of JYNNEOS Vaccine and in Unvaccinated Persons - 29 U.S. Jurisdictions, May 22-September 3, 2022.

As of November 14, 2022, monkeypox (mpox) cases had been reported from more than 110 countries, including 29,133 cases in the United States.* Among U.S. cases to date, 95% have occurred among males (1). After the first confirmed U.S. mpox case on May 17, 2022, limited supplies of JYNNEOS vaccine (Modified Vaccinia Ankara vaccine, Bavarian Nordic) were made available to jurisdictions for persons exposed to mpox. JYNNEOS vaccine was approved by the Food and Drug Administration (FDA) in 2019 as a 2-dose series (0.5 mL per dose, administered subcutaneously) to prevent smallpox and mpox disease.† On August 9, 2022, FDA issued an emergency use authorization to allow administration of JYNNEOS vaccine by intradermal injection (0.1 mL per dose) (2). A previous report on U.S. mpox cases during July 31-September 3, 2022, suggested that 1 dose of vaccine offers some protection against mpox (3). This report describes demographic and clinical characteristics of cases occurring ≥14 days after receipt of 1 dose of JYNNEOS vaccine and compares them with characteristics of cases among unvaccinated persons with mpox and with the vaccine-eligible vaccinated population in participating jurisdictions. During May 22-September 3, 2022, among 14,504 mpox cases reported from 29 participating U.S. jurisdictions,§ 6,605 (45.5%) had available vaccination information and were included in the analysis. Among included cases, 276 (4.2%) were among persons who had received 1 dose of vaccine ≥14 days before illness onset. Mpox cases that occurred in these vaccinated persons were associated with lower percentage of hospitalization (2.1% versus 7.5%), fever, headache, malaise, myalgia, and chills, compared with cases in unvaccinated persons. Although 1 dose of JYNNEOS vaccine offers some protection from disease, mpox infection can occur after receipt of 1 dose, and the duration of protection conferred by 1 dose is unknown. Providers and public health officials should therefore encourage persons at risk for acquiring mpox to complete the 2-dose vaccination series and provide guidance and education regarding nonvaccine-related prevention strategies (4).

Incidence of Multisystem Inflammatory Syndrome in Children Among US Persons Infected With SARS-CoV-2.

Importance: Multisystem inflammatory syndrome in children (MIS-C) is associated with recent or current SARS-CoV-2 infection. Information on MIS-C incidence is limited. Objective: To estimate population-based MIS-C incidence per 1 000 000 person-months and to estimate MIS-C incidence per 1 000 000 SARS-CoV-2 infections in persons younger than 21 years. Design, Setting, and Participants: This cohort study used enhanced surveillance data to identify persons with MIS-C during April to June 2020, in 7 jurisdictions reporting to both the Centers for Disease Control and Prevention national surveillance and to Overcoming COVID-19, a multicenter MIS-C study. Denominators for population-based estimates were derived from census estimates; denominators for incidence per 1 000 000 SARS-CoV-2 infections were estimated by applying published age- and month-specific multipliers accounting for underdetection of reported COVID-19 case counts. Jurisdictions included Connecticut, Georgia, Massachusetts, Michigan, New Jersey, New York (excluding New York City), and Pennsylvania. Data analyses were conducted from August to December 2020. Exposures: Race/ethnicity, sex, and age group (ie, ≤5, 6-10, 11-15, and 16-20 years). Main Outcomes and Measures: Overall and stratum-specific adjusted estimated MIS-C incidence per 1 000 000 person-months and per 1 000 000 SARS-CoV-2 infections. Results: In the 7 jurisdictions examined, 248 persons with MIS-C were reported (median [interquartile range] age, 8 [4-13] years; 133 [53.6%] male; 96 persons [38.7%] were Hispanic or Latino; 75 persons [30.2%] were Black). The incidence of MIS-C per 1 000 000 person-months was 5.1 (95% CI, 4.5-5.8) persons. Compared with White persons, incidence per 1 000 000 person-months was higher among Black persons (adjusted incidence rate ratio [aIRR], 9.26 [95% CI, 6.15-13.93]), Hispanic or Latino persons (aIRR, 8.92 [95% CI, 6.00-13.26]), and Asian or Pacific Islander (aIRR, 2.94 [95% CI, 1.49-5.82]) persons. MIS-C incidence per 1 000 000 SARS-CoV-2 infections was 316 (95% CI, 278-357) persons and was higher among Black (aIRR, 5.62 [95% CI, 3.68-8.60]), Hispanic or Latino (aIRR, 4.26 [95% CI, 2.85-6.38]), and Asian or Pacific Islander persons (aIRR, 2.88 [95% CI, 1.42-5.83]) compared with White persons. For both analyses, incidence was highest among children aged 5 years or younger (4.9 [95% CI, 3.7-6.6] children per 1 000 000 person-months) and children aged 6 to 10 years (6.3 [95% CI, 4.8-8.3] children per 1 000 000 person-months). Conclusions and Relevance: In this cohort study, MIS-C was a rare complication associated with SARS-CoV-2 infection. Estimates for population-based incidence and incidence among persons with infection were higher among Black, Hispanic or Latino, and Asian or Pacific Islander persons. Further study is needed to understand variability by race/ethnicity and age group.

Pathogenicity and genetic variation of 3 strains of Corynebacterium bovis in immunodeficient mice.

Corynebacterium bovis has been associated with hyperkeratotic dermatitis and acanthosis in mice. We studied 3 different strains of C. bovis: one previously described to cause hyperkeratotic dermatitis (HAC), one that infected athymic nude mice without leading to the classic clinical signs, and one of bovine origin (ATCC 7715). The 3 strains showed a few biochemical and genetic differences. Immunodeficient nude mice were housed in 3 independent isolators and inoculated with pure cultures of the 3 strains. We studied the transmission of these C. bovis studies to isolator-bedding and contact sentinels housed for 5 to 12 wk in filter-top or wire-top cages in the respective isolators. Using a 16S rRNA-based qPCR assay, we did not find consistent differences in growth and transmission among the 3 C. bovis strains, and neither the incidence nor severity of hyperkeratosis or acanthosis differed between strains. Housing in filter-top compared with wire-top cages did not alter the morbidity associated with any of the strains. Our findings confirmed the variability in the gross and histologic changes associated with C. bovis infection of mice. Although bacteriology was a sensitive method for the detection of Corynebacterium spp., standard algorithms occasionally misidentified C. bovis and several related species. Our study demonstrates that PCR of skin swabs or feces is a sensitive and specific method for the detection of C. bovis infection in mice. An rpoB-based screen of samples from North American vivaria revealed that HAC is the predominant C. bovis strain in laboratory mice.