Booster Doses of Anti COVID-19 Vaccines: An Overview of Implementation Policies among OECD and EU Countries

Abstract

The need for an anti-COVID-19 booster dose posed an organizational challenge for health policy makers worldwide. Therefore, this study aimed to explore the health policies regarding the booster dose through an overview of recommendations issued in high-income countries. Between 10 November and 16 December 2021, the authors searched for state-level official documents about the offer of the booster dose, considering the 43 countries belonging to the European Union (EU) or the Organisation for Economic Co-operation and Development (OECD). Mainly due to the lack of English translation, 15 countries were excluded. A total of 135 documents were selected. Almost all the countries started administering the booster dose between September and November 2021. The most used products were mRNA vaccines, followed by Vaxzevria-AstraZeneca and Jcovden-Janssen/Johnson & Johnson. All countries established criteria to define categories of individuals to be vaccinated as a priority. A six/five-months interval was the main choice for general population vaccinated with mRNA vaccines, while shorter intervals were chosen for vulnerable individuals or other vaccines. Despite diversities related to the differences in health systems, economical resources, and population numbers, and the need to adapt all these factors to a massive vaccination campaign, a progressive convergence towards the same vaccination policies was highlighted.

Incidence and Determinants of Symptomatic and Asymptomatic SARS-CoV-2 Breakthrough Infections After Booster Dose in a Large European Multicentric Cohort of Health Workers-ORCHESTRA Project

“…Significant variability was observed across centres in the proportion of booster dose administration. These differences could be explained by the different starting periods of the vaccination campaign in various European countries and by different legal obligations for HW [ 17 ]. Desye reported that male HW were significantly more likely to accept the COVID-19 vaccine than female HW [ 18 ].…”

“…The second aspect is related to pandemic waves and the spread of variants that may escape the vaccination effect, which is likely more relevant during and after the period when the booster dose was administered. The first studies on BI after booster doses were conducted among Israeli HW due to the early start of all vaccination phases in this country (in July 2021) compared to elsewhere in the world [ 17 ]. Among 4,973 HW who received a third BNT162b2 dose since August 2021, Oster et al found a 0.7% rate of BI, far less the 21.4% reported among HW who received only the two-dose regimen, indicating substantial protection by a third vaccine dose [ 20 ].…”

I want to be safe: understanding the main drivers behind vaccination choice throughout the pandemic

“…The first vaccination cycle (the first and second dose) included two doses administered a few weeks apart (usually 3–12 weeks; [ 7 ]). As the pandemic progressed and new virus variants emerged, most European countries responded by implementing additional booster doses [ 8 ] to combat the rising epidemiological curve (Fig. 1 ).…”

The impact of COVID-19 booster vaccination in the current pregnancy during the Omicron waves on maternal and perinatal outcomes: a multicentre observational study

“…In the general population, recent studies reported that primary COVID-19 vaccination efficacy was up to 90% within 6 months, decreasing rapidly to 34-80% after this period [7]. So, the reduced efficacy of vaccines may be related to the new variant but also to the time from the last vaccination which emphasizes that COVID-19 vaccine booster doses are required for restoring vaccine efficacy and limiting virus circulation [7,8]. However, pregnant women remain hesitant to get booster shots of vaccine and there are still little data on the interest of booster vaccination during pregnancy in improving maternal and fetal protection against this widely spread variant [9].…”