RESUMEN
INTRODUCTION: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) booster vaccination campaign and the emergence of SARS-CoV-2 Omicron variants impact the prevalence and levels of SARS-CoV-2 antibodies in the Netherlands. In this study we determined antibody levels across age groups, the impact of Omicron variant infections, and the effect of booster vaccinations on antibody levels. METHODS: In September and December 2021 and in February 2022, over 2000 Dutch blood donors were tested for presence of SARS-CoV-2 antibodies. Donations were selected based on age, sex, and region of residence, to provide an optimal coverage and representation of the Dutch population. RESULTS: Levels of vaccination-induced spike antibodies decreased over time in all age groups. Donors vaccinated with Janssen or AstraZeneca had significantly lower antibody levels than donors vaccinated with Pfizer or Moderna vaccine. Boostering with an mRNA vaccine elevated antibody levels in all age-groups irrespective of the initial vaccine. In donors aged < 56 years, the proportion of infected donors almost doubled between December 2021 and February 2022. CONCLUSION: The booster vaccination campaign increased antibody levels in all age-groups. After a booster vaccination, donors initially vaccinated with AstraZeneca or Janssen vaccine showed antibody levels similar to donors initially vaccinated with an mRNA vaccine. The emergence of the SARS-CoV-2 Omicron variant in the Netherlands caused a substantial increase in donors with infection-induced antibodies, especially among younger donors.
Asunto(s)
Donantes de Sangre , COVID-19 , Humanos , SARS-CoV-2 , COVID-19/epidemiología , COVID-19/prevención & control , Anticuerpos Antivirales , VacunaciónRESUMEN
OBJECTIVE: To gain an insight into the waiting periods for cataract, arthroscopic knee and total hip operations and the patients' opinion on this subject. DESIGN: Retrospective study. SETTING: The district of Groningen, the Netherlands. METHOD: A study population of 300 national health insurants who underwent a cataract operation (100), an arthroscopic knee operation (100) or a total hip operation (100) in 1992 and 50 private insurants who underwent a cataract operation in 1992, was obtained by a select sampling. By a structured questionnaire, information about basic variables (age, gender, education, occupation, perceived urgency and form of insurance), waiting periods and opinions on the waiting periods was gathered. RESULTS: The waiting periods between the specialist consultation and the operation were 5.2 and 7 months for eye, knee and hip patients respectively. The waiting period per hospital varied from 4-7 months for an eye operation, 1-4 months for a knee operation and 2.5-12 months for a hip operation. The waiting period was not affected by basic variables, except the waiting period for hip operation which benefited from a high urgency declaration by the specialist. 60% of the eye patients, 45% of the knee patients and 47% of the hip patients were satisfied about the waiting period. 15% of all patients were dissatisfied about it. CONCLUSION: Waiting periods for operations in this study were not determined by patient-specific basic variables, varied strongly between hospitals and did not cause discontent among the majority of the patients, despite durations of mostly several months.