Self-Reported adverse events among Chinese healthcare workers immunized with COVID-19 vaccines composed of inactivated SARS-CoV-2

High SARS-CoV-2 infection rate in children unvaccinated with COVID-19 vaccine in Changzhou, China, shortly after lifting zero-COVID-19 policy in December 2022

BACKGROUND

China experienced an overwhelming COVID-19 pandemic from middle December 2022 to middle January 2023 after lifting the zero-COVID-19 policy on December 7, 2022. However, the infection rate was less studied. We aimed to investigate the SARS-CoV-2 infection rate in children shortly after discontinuation of the zero-COVID-19 policy.

METHODS

From February 20 to April 10, 2023, we included 393 children aged 8 months to less than 3 years who did not receive COVID-19 vaccination and 114 children aged 3 to 6 years who received inactivated COVID-19 vaccines based on the convenience sampling in this cross-sectional study. IgG and IgM antibodies against nucleocapsid (N) and subunit 1 of spike (S1) of SARS-CoV-2 (anti-N/S1) were measured with commercial kits (Shenzhen YHLO Biotech, China).

RESULTS

Of the 393 unvaccinated children (1.5 ± 0.6 years; 52.2% boys), 369 (93.9%) were anti-N/S1 IgG positive. Of the 114 vaccinated children (5.3 ± 0.9 years; 48.2% boys), 112 (98.2%) were anti-N/S1 IgG positive. None of the unvaccinated or vaccinated children was anti-N/S1 IgM positive. The median IgG antibody titers in vaccinated children (344.91 AU/mL) were significantly higher than that in unvaccinated children (42.80 AU/mL) (P < 0.0001). The positive rates and titers of anti-N/S1 IgG had no significant difference between boys and girls respectively.

CONCLUSION

Vast majority of children were infected with SARS-CoV-2 shortly after ending zero-COVID-19 policy in China. Whether these unvaccinated infected children should receive COVID-19 vaccine merits further investigation.

Sex differences in the relationship between post-vaccination adverse reactions, decision regret, and WTP for the booster dose of COVID-19 vaccine in Taizhou, China

This study investigated sex differences in the relationship between post-vaccination adverse reactions, decision regret, and willingness to pay (WTP) for the booster dose of COVID-19 vaccines. This research carried out an online cross-sectional investigation among healthcare workers (HCWs) in Taizhou, China. In total, 1,054 respondents (165 males and 889 females) have received two-dose COVID-19 vaccination. We performed descriptive analysis, chi-square test, and mediation analysis on the exported data. In this study, 67 (40.6%) males and 429 (48.3%) females had WTP for the booster dose. Our study presented that decision regret mediated the effect of adverse reactions after vaccination on WTP for the booster dose in both male and female groups. In males, decision regret played a completely mediating role, while in females, it acted as a partial mediator. Sex differences in the relationship between post-vaccination side effects, decision regret, and WTP for the third dose were demonstrated in a sample of healthcare workers.

Side Effects of COVID-19 Vaccines in Pregnant and Lactating Mexican Women and Breastfed Infants: A Survey-Based Study

COVID-19 vaccines' safety has been extensively studied; however, further analysis is required in pregnant women, nursing mothers, and breastfed infants. Our aim was to compare the extension and severity of self-reported COVID-19 vaccine side effects in pregnant and breastfeeding women, and breastfed infants. In this cross-sectional study, COVID-19-vaccinated subjects were enrolled using an online survey in Mexico. Women were classified by pregnancy and breastfeeding status at the time of vaccination (n = 3167). After the first or only dose, there was a trend toward fewer systemic effects in pregnant women (p = 0.06). BNT162b2 (Pfizer-BioNTech) had a higher frequency of local symptoms in pregnancy. Lactating women experienced fewer local symptoms after the first or single dose (p = 0.04) and the opposite occurred after the second dose (p = 0.001). ChAdOx1 (AstraZeneca) increased the chances of developing both local and systemic symptoms after the first dose but decreased them after the second dose. The severity was similar across groups, although the result of lack of association in pregnancy requires studies with a larger sample size. Irritability was the most reported symptom in breastfed infants. This study contributes to the knowledge about the side effects in pregnant and lactating women, and breastfed babies.

Female reproduction and abnormal uterine bleeding after COVID-19 vaccination

Coronavirus disease 2019 (COVID-19) vaccines have been widely administered throughout the global community to minimize the morbidity and mortality caused by the COVID-19 pandemic. Although generally well-tolerated, these vaccines have generated some unwanted consequences, including thrombosis and menstrual irregularities. The effect of vaccination on female reproductive function has also been questioned. The aim of this review is to give readers a clear understanding of the effects of COVID-19 vaccines on thrombosis, reproductive function, and menstrual irregularities by systemically analyzing the available literature. The available evidence suggests that COVID-19 vaccines have a minimal impact on ovarian reserve. Furthermore, in vitro fertilization outcomes after COVID-19 vaccination remain unimpaired compared to those who did not receive the vaccines. Current evidence supports a certain degree of impact of COVID-19 vaccines on the menstrual cycle, with the most frequent alteration being menstrual irregularity, followed by menorrhagia. These changes are generally well-tolerated and transient, lasting less than 2 months. This review, by providing information with up-to-date references on this issue, may enhance readers' understanding of the impact of COVID-19 vaccines on female reproductive function and the menstrual cycle.

Reduced antibody response to COVID-19 vaccine composed of inactivated SARS-CoV-2 in diabetic individuals

Background

Patients with type 2 diabetes mellitus (T2DM) are at increased risk for COVID-19 related morbidity and mortality. Antibody response to COVID-19 vaccine in T2DM patients is not very clear. The present work aims to evaluate the antibody response to the inactivated SARS-CoV-2 vaccine in this population.

Methods

Two groups of subjects with no history of SARS-CoV-2 infection were included: 63 T2DM patients and 56 non-T2DM controls. Each participant received two doses of inactivated COVID-19 vaccine. IgG antibodies against the nucleocapsid (N) and spike (S) proteins of SARS-CoV-2 (anti-N/S IgG) and receptor binding domain (RBD) proteins (anti-RBD IgG) were quantitatively evaluated by the electrochemiluminescence immunoassays, respectively.

Results

It was observed that the positive rates and titers of anti-N/S IgG and anti-RBD IgG in T2DM patients were significantly lower than those in controls, respectively (anti-N/S: 85.7 vs. 98.2%, P = 0.034; 25.48 vs. 33.58 AU/ml P = 0.011; anti-RBD: 85.7 vs. 96.4%, P = 0.044; 15.45 vs. 22.25 AU/ml, P = 0.019). Compared to non-T2DM subjects, T2DM patients with uncontrolled glycemia showed lower positive antibody rates and titers (anti-N/S IgG: 75% and 13.30 AU/ml; anti-RBD IgG: 75% and 11.91 AU/ml, respectively, all P < 0.05), while T2DM patients with controlled glycemia had similar positive antibody rates and titers (anti-N/S IgG: 94.3% and 33.65 AU/ml; and anti-RBD IgG: 94.3% and 19.82 AU/ml, respectively, all P > 0.05).

Conclusion

In the analysis performed, the data indicate that T2DM patients with uncontrolled glycemia showed a lower level of IgG antibodies compared to non-diabetic controls and individuals with controlled glycemia when immunized with the inactivated COVID-19 vaccine.

COVID-19 vaccine hesitancy and associated factors among infertile couples undergoing assisted reproductive treatment

Although periconception vaccination is important to maternal and neonatal health, little is known about the COVID-19 vaccine hesitancy among infertile couples seeking fertility treatment. Thus, we conducted this survey among infertile patients in a reproductive medicine center, between September 2021 and December 2021, to estimate the prevalence of COVID-19 vaccine hesitancy and its influencing factors. Information was collected through face-to-face interviews among volunteers. Among the 987 included interviewees, 17.33% reported hesitancy in primary vaccination, 25.63% reported hesitancy in booster vaccination, and 32.32% delayed the primary vaccination. Hesitancy in primary vaccination was associated with unexplained infertility (OR: 1.77, 95% CI: 1.05-2.98), ongoing IVF treatment (OR: 2.17, 95% CI: 1.22-3.89), concerns for vaccine safety (OR: 4.13, 95% CI: 2.66-6.42), effectiveness (OR: 1.62, 95% CI: 1.15-2.28), and influence on pregnancy (OR: 2.80, 95% CI: 1.68-4.67). These factors were also associated with hesitancy in booster vaccination. Delay of the primary vaccination was inversely associated with a college or above degree (OR: 0.49, 95% CI: 0.27-0.87), previous history of influenza vaccination (OR: 0.67, 95% CI: 0.46-0.98), and was positively associated with concerns for the influence on pregnancy (OR: 7.78, 95% CI: 5.01-12.07). It is necessary to carry out targeted education program by health professionals to publicize the benefits of periconception vaccination, and to reduce the resistance to COVID-19 vaccine among infertile couples.

COVID-19 vaccination coverage among adolescents aged 12–17 years in three provinces of eastern China: A cross-sectional survey, 2021

High vaccination coverage is essential to prevent and control the spread of the COVID-19 epidemic. Currently, the real-world acceptance of COVID-19 vaccines among adolescents aged 12–17 years in China has not been reported. We aimed to assess the acceptance rate of COVID-19 vaccination among adolescents in eastern China and to identify factors associated with the intention to get vaccinated against COVID-19. We conduct a cross-sectional questionnaire survey among adolescents from three provinces in the eastern part of China from 16 August to 28 October 2021. The questionnaires were distributed to 2,100 students, and 2,048 students completed the questionnaires. The results showed that 98.4% (2,016/2,048) of adolescents had received at least one dose of the COVID-19 vaccine and 1.6% (32/2,048) declined the vaccination. The participants from rural districts, or whose parents were vaccinated, were more likely to accept the vaccine. The main reason for declining vaccination was worry about vaccine safety (25%). The main adverse event after the vaccination was pain at the injection site. In conclusion, the vaccine coverage rate reached 98.4% among the adolescents in this study, which met the criteria for herd immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The high vaccination rate is beneficial to the prevention and control of the COVID-19 pandemic.

Menstrual abnormalities after COVID-19 vaccines: A systematic review

The objective of this systematic review is to give a comprehensive interpretation of menstrual cycle changes after the COVID-19 vaccination. Additionally, it is imperative to assess reports of menstrual changes following vaccination to dispel concerns that COVID-19 vaccines hinder the likelihood of pregnancy in the long run. A literature review was conducted using digital databases to systematically identify the studies reporting any menstrual abnormalities after the COVID-19 vaccine. Detailed patient-level study characteristics including the type of study, sample size, administered vaccines, and menstrual abnormalities were abstracted. A total of 78 138 vaccinated females were included in this review from 14 studies. Of these, 39 759 (52.05%) had some form of a menstrual problem after vaccination. Due to the lack of published research articles, preprints were also included in this review. Menorrhagia, metrorrhagia, and polymenorrhea were the most commonly observed problems and the overall study-level rate of menstrual abnormality ranged from 0.83% to 90.9%. Age, history of pregnancy, systemic side-effects of COVID-19, smoking, and second dose of COVID-19 vaccine were predictors of menstrual problems after vaccination.