Seasonal and inter-seasonal RSV activity in the European Region during the COVID-19 pandemic from autumn 2020 to summer 2022

© 2023 The Authors. Influenza and Other Respiratory Viruses published by John Wiley & Sons Ltd.Background: The emergence of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in early 2020 and subsequent implementation of public health and social measures (PHSM) disrupted the epidemiology of respiratory viruses. This work describes the epidemiology of respiratory syncytial virus (RSV) observed during two winter seasons (weeks 40–20) and inter-seasonal periods (weeks 21–39) during the pandemic between October 2020 and September 2022. Methods: Using data submitted to The European Surveillance System (TESSy) by countries or territories in the World Health Organization (WHO) European Region between weeks 40/2020 and 39/2022, we aggregated country-specific weekly RSV counts of sentinel, non-sentinel and Severe Acute Respiratory Infection (SARI) surveillance specimens and calculated percentage positivity. Results for both 2020/21 and 2021/22 seasons and inter-seasons were compared with pre-pandemic 2016/17 to 2019/20 seasons and inter-seasons. Results: Although more specimens were tested than in pre-COVID-19 pandemic seasons, very few RSV detections were reported during the 2020/21 season in all surveillance systems. During the 2021 inter-season, a gradual increase in detections was observed in all systems. In 2021/22, all systems saw early peaks of RSV infection, and during the 2022 inter-seasonal period, patterns of detections were closer to those seen before the COVID-19 pandemic. Conclusion: RSV surveillance continued throughout the COVID-19 pandemic, with an initial reduction in transmission, followed by very high and out-of-season RSV circulation (summer 2021) and then an early start of the 2021/22 season. As of the 2022/23 season, RSV circulation had not yet normalised.Peer reviewe

The Czech Surveillance System for Invasive Pneumococcal Disease, 2008-2013: A Follow-Up Assessment and Sensitivity Estimation.

Invasive pneumococcal disease (IPD) is caused by Streptococcus pneumoniae and mostly presents as pneumonia, sepsis or meningitis. A notable portion of IPD cases is vaccine preventable and the pneumococcal conjugate vaccine (PCV) was introduced into the routine childhood immunization programs in many countries during the last decades.Before PCV introduction in the Czech Republic in 2010, a national surveillance system for IPD was implemented in 2008 and further improved in 2011. In this study, we describe the new surveillance system for the first time and measure its sensitivity between 2010 and 2013 using the capture-recapture method. Furthermore, we describe the recent epidemiological trend of IPD, taking sensitivity estimates into account.Between 2010 and 2013 the estimated sensitivity of the overall IPD surveillance increased from 81% to 99%. The sensitivity of individual reporting sources increased from 72% to 87% for the laboratory system and from 31% to 89% for the epidemiological notification system. Crucial for this improvement was the introduction of quarterly report reminders in 2011. Due to positive source dependency, the presented sensitivity estimates are most probably overestimated and reflect the upper limit of reporting completeness. Stratification showed variation in sensitivity of reporting particularly according to region. An effect of the PVC vaccination in the Czech Republic is visible in the incidence of IPD in target age groups (<5 y). This influence was not evident in the total IPD incidence and may interfere with increasing sensitivity of reporting. In 2013, an increase in the IPD incidence was observed. This finding requires further observation and a detailed vaccine impact analysis is needed to assess the current immunization strategy

Number of reported and estimated IPD cases in the CZ according to reporting source (EPIDAT, NRL) from 2010 to 2013.

<p>+ = captured by this source; - = not captured by this source.</p

Estimated reporting sensitivity of the Czech IPD surveillance system by source of reporting and in total, 2010 to 2013.

<p>Error bars reflect 95% confidence intervals.</p

Timeline of events related to the introduction of PCV vaccination and IPD surveillance in the Czech Republic, 2005–2013.

<p>* Licensed and available on the private market.</p

Estimated sensitivity of IPD reporting stratified by region according to the Nomenclature of Units for Territorial Statistics (NUTS 2), 2013, CZ.

<p>Error bars reflect 95% confidence intervals.</p

Structure and levels of the Czech IPD surveillance system, based on two reporting sources.

<p>NRL = National Reference Laboratory for streptococcal infections, EPIDAT = Czech national epidemiological database, MoH = Ministry of Health, TESSy = The European Surveillance System.</p