CoronaVac is an inactivated vaccine containing whole-virion SARS-CoV-2, which has been approved in 43 countries for emergency use as of 26 November 2021. However, the long-term immune persistence of the CoronaVac vaccine is still unknown. Here, we reported the status of the persistence of antibodies and cellular responses within 12 months after two doses of CoronaVac. Such data are crucial to inform ongoing and future vaccination strategies to combat COVID-19.

Background: China pledged to join the global effort to eliminate measles by 2012. To improve measles control strategy, the epidemic trend and population immunity of measles were investigated in 1951–2011 in Beijing. Methods: The changing trend of measles since 1951 was described based on measles surveillance data from Beijing Centre of Disease Control and Prevention (CDC). The measles vaccination coverage and antibody level were assessed by routinely reported measles vaccination data and twenty-one sero-epidemiological surveys. Results: The incidence of measles has decreased significantly from 593.5/100,000 in 1951 (peaked at 2721.0/100,000 in 1955), to 0.5/100,000 in 2011 due to increasing vaccination coverage of 95%-99%. Incidence rebounded from 6.6/100,000 to 24.5/100,000 since 2005 and decreased after measles vaccine (MV) supplementary immunization activities (SIAs) in 2010. Measles antibody positive rate was 85%-95% in most of years since 1981. High-risk districts were spotted in Chaoyang, Fengtai and Changping districts in recent 15 years. Age-specific incidence and proportion of measles varied over time. The most affected population were younger children of 1–4 years before 1978, older children of 5–14 years in 1978–1996, infant of <1 years and adults of ≥15 years in period of aim to measles elimination. Conclusion: Strategies at different stages had a prevailing effect on the epidemic dynamics of measles in recent 60 years in Beijing. It will be essential to validate reported vaccination coverage, improve vaccination coverage in adults and strengthen measles surveillance in the anticipated elimination campaign for measles.

This real-world study explores the effect of coronavirus disease 2019 (COVID-19) inactivated vaccines on the prevention of asymptomatic or mild Delta or Omicron variant infections progressing to pneumonia. Association between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia cases and vaccination was measured with a multivariable logistic regression, stratified by genotype and age groups. We recruited 265 cases (111 (41.9%) infected with Delta and 154 (58.1%) with Omicron variants). There were 22 asymptomatic infected individuals, 156 mild cases without pneumonia, and 87 moderate cases with pneumonia. There was a markedly increased risk of progression to pneumonia in Delta infected cases, unvaccinated, or partially vaccinated COVID-19 patients with diabetes and those aged ≥60 years. Patients who had completed booster doses of inactivated vaccines had a reduced risk of 81.6% (95% CI: 55.6–92.4%) in progressing to pneumonia over those who were unvaccinated or partially vaccinated. The risk of progressing to pneumonia was less reduced by 88.7% (95% CI: 56.6–97%) and 73.9% (95% CI: 1.4–93.1%) among Delta and Omicron-infected patients, and was reduced by 78.5% (95% CI: 45.3–91.6%) and 94.1% (95% CI: 21.5–99.6%) among patients aged <60 and ≥60 years, respectively. Our data indicated that a complete vaccination with a booster reduced the risk of asymptomatic or mild Delta or Omicron variant COVID-19 progressing to pneumonia and, thus, reduced the pressure of severe illness on medical resources.

Hospital-based case control studies have found family history of herpes zoster (HZ) was associated with risk of HZ, but the role of family history is not fully examined for other HZ-associated outcomes such as recurrent HZ, occurrence of postherpetic neuralgia (PHN), and HZ with different pain severities. We conducted a population-based matched case control study. HZ cases that occurred during December 1, 2011 to November 30, 2012 were identified by face-to-face interview with all residents of eight selected communities/villages from three districts of Beijing, China. Medical records were reviewed for those who sought healthcare for HZ. For each case-patient, three, age-matched controls (±5 years) without HZ were enrolled from the same community/village of the matched case. Data on family history of HZ were collected by interview and only defined among first-degree relatives. A total of 227 case-patients and 678 matched controls were enrolled. Case-patients were more likely to report a family history of HZ [odds ratio (OR) =2.4, P = 0.002]. Compared with controls, association of family history decreased from HZ with PHN to HZ without PHN (OR = 6.0 and 2.3, respectively; P = 0.002 for trend), from recurrent HZ to primary HZ (OR = 9.4 and 2.2, respectively; P = 0.005 for trend), and from HZ with moderate or severe pain to HZ with mild or no pain (OR = 3.2 and 0.8, respectively; P < 0.001 for trend). Family history of HZ was associated with HZ occurrence and was more likely in HZ case-patients with PHN, recurrences, and painful HZ.

Controversies persist about the protective effects of vaccines against acute cardiovascular events. Using electronic medical records from hospitals and influenza vaccine administration data in Beijing, China, we studied individuals vaccinated between January 1, 2016, and December 31, 2018, who experienced at least one acute cardiovascular event within two years. A self-controlled case series design calculated the relative incidence (RI) and 95% confidence interval (CI) of acute cardiovascular events within one year after vaccination. Among 1647 participants (median age: 65 years, 38.43% female), the risk of events 29–365 days post-vaccination was 0.76 times the baseline level (RI: 0.76; 95% CI: 0.68–0.84). The protective effect was more pronounced in younger participants (P = 0.043) and those without cardiovascular history (P < 0.001), while acute respiratory infection (P = 0.986) and vaccination frequency (P = 0.272) had no impact. Influenza vaccines offer protection against acute cardiovascular events for at least one year, suggesting potential for cardiovascular disease prevention.

To determine the status of immune responses after primary and booster immunization for SARS-CoV-2 variants and evaluate the differences in disease resistance based upon titers of neutralizing antibodies (NAbs) against the variants. Participants aged 18–59 years received 2 doses of inactivated COVID-19 vaccine, 14 days apart, and a booster dose after 12 months. Blood samples were collected before vaccination (baseline), 1 and 6 months after primary immunization, and at multiple instances within 21 days of the booster dose. NAbs against the spike protein of Wuhan-Hu-1 and 3 variants were measured using pseudovirus neutralization assays. Of 400 enrolled participants, 387 completed visits scheduled within 6 months of the second dose and 346 participants received the booster dose in the follow-up research. After 1 month of primary immunization, geometric mean titers (GMTs) of NAbs peaked for Wuhan-Hu-1, whereas GMTs of other variants were <30. After 6 months of primary immunization, GMTs of NAbs against all strains were <30. After 3 days of booster immunization, GMTs were unaltered, seroconversion rates reached approximately 50% after 7 days, and GMTs of NAbs against all strains peaked at 14 days. Two-dose of inactivated COVID-19 vaccine induced the formation of NAbs and memory-associated immune responses, and high titers of NAbs against the variants obtained after booster immunization may further improve the effectiveness of the vaccine.