ABSTRACT
IntroductionCOVID-19 vaccines have been highly effective in reducing morbidity and mortality during the pandemic. While primary series vaccination rates are generally high in Southeast Asian (SEA) countries, various factors have limited the rollout and impact of booster doses.Areas coveredWe reviewed 79 studies in the publicly available International Vaccine Access Center (IVAC) VIEW-hub platform on vaccine effectiveness (VE) after primary immunizations with two-dose schedules. VE data were reported for SARS-CoV-2 infection, COVID-19-related hospitalizations and deaths, and stratified across variants of concern (VOC), age, study design and prior SARS-CoV-2 infection for mRNA vaccines (BNT162b2, mRNA-1273 and combinations of both), vector vaccines (AstraZeneca, AZD1222 “Vaxzevria”) and inactivated virus vaccines (CoronaVac).Expert opinionThe most-studied COVID-19 vaccines provide consistently high (>90%) protection against serious clinical outcomes like hospitalizations and deaths, regardless of variant. Additionally, this protection appears equivalent for mRNA vaccines and vector vaccines like AZD1222, as supported by our analysis of local Asian and relevant international data, and by insights from SEA experts. Given the continued impact of COVID-19 hospitalizations and deaths on healthcare systems worldwide, encouraging vaccination strategies that can reduce this burden is more relevant than attempting to prevent broader but milder infections with specific variants, including Omicron.Article highlights - VE was high and comparable for both AZD1222 and mRNA vaccine types (91%-93%) in protecting against hospitalization and death from COVID-19, regardless of age.- VE against symptomatic infections trended higher (though not significantly) for mRNA-based vaccines compared to AZD1222.- Waning of VE since time of vaccination was observed for symptomatic infections but was limited for serious COVID-19 outcomes. A sub-analysis of studies with comparative arms evaluating the VE of different vaccines in the same settings also confirmed these observations for all VOC assessed, with all vaccines conferring a high level of protection against serious outcomes.- For Omicron, there is limited comparative data within the IVAC dataset, however, expert review of emerging data suggests that VE against all outcomes is lower for all COVID-19 vaccines, than for the Delta variant.- Data from the UK indicate that VE improves with a booster dose and that VE continues to be very similar, irrespective of the type of vaccine used.- Importantly, all COVID-19 vaccines evaluated here have favorable benefit/risk profiles.- Although many SEA countries have high rates of primary vaccination, there are still challenges to achieving high booster dose coverage. The results of this analysis suggest that the most effective way to achieve vaccine booster targets, particularly in resource-limited settings, would simply be to consider any vaccines which have good safety and comparable effectiveness profiles, particularly against severe outcomes, and that are accessible and optimal for the local situation.- This review reinforces the value of real-world evidence to support efforts advocating for the completion of primary series and booster vaccinations where appropriate, especially to restore VE against emerging VOC such as Omicron. However, data gaps still persist, given the lag between the emergence of new variants, updated vaccine schedules and VE data to inform their impact.
Subject(s)
COVID-19ABSTRACT
Evaluation of vaccine effectiveness over time against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection or coronavirus disease 2019 (COVID-19) is important. Evidence on effectiveness over time for the CoronaVac vaccine is lacking despite its widespread use globally. In Malaysia, a diverse set-up of COVID-19 vaccines was rolled out nationwide, and the waning of vaccine protection is a concern. We aimed to investigate and compare waning vaccine effectiveness against COVID-19 infections, COVID-19 related ICU admission and COVID-19 related deaths for BNT162b2 and CoronaVac vaccines. In this observational study, we consolidated nationally representative data on COVID-19 vaccination and patients' outcomes. Data on all confirmed COVID-19 cases from 1 to 30 September 2021 were used to compare vaccine effectiveness between the 'early' group (fully vaccinated in April to June 2021) and the 'late' group (fully vaccinated in Jul to Aug 2021). We used a negative binomial regression model to estimate vaccine effectiveness against COVID-19 infections for both 'early' and 'late' groups, by comparing the rates of infection for individuals vaccinated in the two different periods relative to the unvaccinated. Among confirmed COVID-19 cases, we used logistic regression to estimate and compare vaccine effectiveness against ICU admission and deaths between the two different periods. For BNT162b2, vaccine effectiveness against COVID-19 infections declined from 90.8% (95% CI 89.4, 92.0) in the late group to 79.1% (95% CI 75.8, 81.9) in the late group. Vaccine effectiveness for BNT162b2 against ICU admission and deaths were comparable between the two different periods. For CoronaVac, vaccine effectiveness waned against COVID-19 infections from 74.4% in the late group (95% CI 209 70.4, 77.8) to 30.0% (95% CI 18.4, 39.9) in the early group. It also declined significantly against ICU admission, dropping from 56.1% (95% CI 51.4, 60.2) to 29.9% (95% CI 13.9, 43.0). For deaths, however, CoronaVac's effectiveness did not wane after three to five months of full vaccination. Vaccine effectiveness against COVID-19 infections waned after three to five months of full vaccination for both BNT162b2 and CoronaVac in Malaysia. Additionally, for CoronaVac, protection against ICU admission declined as well. Evidence on vaccine effectiveness over time informs evolving policy decisions on vaccination.
Subject(s)
COVID-19 , Coronavirus Infections , DeathABSTRACT
Purpose: This study aimed to investigate the psychological distress and its associated factors among cancer survivors in Malaysia during the COVID-19 pandemic.Methods: An anonymous Internet-based study was conducted between 23 April and 26 June 2020. During the study period, the country underwent Phase 3 and Phase 4 of the Movement Control Order (MCO), Conditional Movement Control Order (CMCO), and Recovery Movement Control Order (RMCO). Psychological distress was measured using the Hospital Anxiety and Depression Scale (HADS), which is a 14-item self-assessment scale for measuring distress (total HADS score (HADS-T)) with two subscales, namely anxiety (HADS-A) and depression (HADS-D). Results: From a total of 631 responses received, the proportion of participants with abnormal anxiety and depression was 29.0% and 20.9%, respectively. Distress was reported in 23.0% of the respondents. A total of 16.45% had combined abnormal anxiety and depression. The highest HADS-A (6.10; 95% CI 5.64‒6.56), HADS-D (5.61; 95% CI 5.14‒6.08), and HADS-T (11.71; 95% CI 10.84‒12.58) scores were reported among respondents during Phase 4 of the MCO. Partial least squares-based structural equation modelling (PLS-SEM) revealed that self-perceived health status, perceived susceptibility, and severity of COVID-19 have the greatest effect, leading to higher HADS-A, HADS-D, and HADS-T scores. Conclusion: Heightened psychological distress was evident in cancer survivors particularly during the enforcement of the MCO over COVID-19. Providing support to address cancer survivors’ psychological and emotional needs during the COVID-19 pandemic is essential.Implication for cancer survivors: Cancer survivors or their carers should be made aware of the high psychological risk during infectious disease outbreaks and seek timely support.