As the coronavirus disease (COVID-19) pandemic is not over and the severe acute respiratory syndrome coronavirus (SARS-CoV-2) will likely become endemic, it is important to reflect on systems to detect and monitor the spread and evolution of the virus. Moreover, careful consideration is needed to prepare sentinel surveillance systems for the future, when testing for SARS-CoV-2, influenza viruses and possibly other viruses with public health impact, such as respiratory syncytial virus (RSV), needs to be integrated.
The first cases of COVID-19 in Europe were identified on 24 January 2020 in France, and hereafter, uncontrolled community transmission was detected in the United Kingdom (UK) and Italy in February, and in Spain in early March. Most European countries have shown that consistent application of societal and public health measures can slow person-to-person spread of SARS-CoV-2. These measures included for instance isolation, contact tracing, quarantine of contacts and detection of active cases through testing. In addition, public health interventions included physical distancing, hand hygiene and widespread use of face masks in public. Whereas the surge of outbreaks and the timing of measures taken differed across countries, most countries at some point imposed lockdowns and curfews, effectively shutting down non-essential economic activity to minimise in-person interactions to contain the virus. However, many countries experienced a surge in cases when measures were relaxed.
In March 2020, the World Health Organization (WHO) recommended that in addition to outbreak investigation and management, countries should set up and maintain enhanced influenza surveillance activities. Rather than setting up new systems, the European Centre for Disease Prevention and Control (ECDC) and WHO recommended that, when possible, countries should adapt existing respiratory disease surveillance systems to monitor the spread of COVID-19, such as hospital-based severe acute respiratory infection (SARI), primary care acute respiratory infection (ARI) and influenza-like illness (ILI). These surveillance systems should be used to detect and monitor community transmission of SARS-CoV-2 according to four transmission scenarios – no cases, sporadic cases, clusters of cases, and community transmission with the aims to (i) monitor geographical spread, severity, and intensity of transmission; (ii) collect genomic information to be considered in the development of drugs and vaccines; (iii) collect data on risk factors for disease to enable targeted prevention; (iv) monitor the impact on health systems; and (v) monitor the impact of mitigation measures.
In Europe, influenza surveillance is performed jointly by ECDC and the WHO Regional Office for Europe (WHO/EURO). The data from the countries’ weekly reports are summarised in the Flu News Europe, a weekly bulletin produced by the two organisations. Data related to SARS-CoV-2 detection and COVID-19 epidemiology were rapidly added to the weekly reports. In addition, 15 countries across Europe participate in the Influenza-Monitoring Vaccine Effectiveness in Europe (I-MOVE) network to share information and estimate influenza vaccine effectiveness across influenza seasons, including both primary and secondary care. Established in 2007, the I-MOVE network includes primary care, hospital, and laboratory surveillance networks that measure influenza vaccine effectiveness. The network has vast experience in multicentre studies. Sentinel primary care practitioners collect specimens from a sample of patients who present with ILI or ARI within 8 days of symptom onset. These specimens are tested at regional reference laboratories. Participating countries/regions adapt the generic protocol to their specific situation. In response to the COVID-19 pandemic, this network was expanded to include COVID-19 in the I-MOVE-COVID-19 Consortium. The expansion was designed to strengthen surveillance systems in the participating countries so that European countries detected and responded to COVID-19 cases as rapidly as possible.
The I-MOVE-COVID-19 primary care network aims to share information and to conduct studies on sentinel surveillance for COVID-19 to better understand the virus and its spread. The network comprises six sentinel sites in European Union (EU) countries (France, Ireland, the Netherlands, Portugal, Spain and Sweden) and two sites in the UK (England and Scotland) (see Supplementary Table S1 for a description of the network).
Here we present the experiences of these I-MOVE-COVID-19 network countries in adapting their primary care influenza sentinel surveillance systems for COVID-19 surveillance. Our objectives are to map the adaptations to the surveillance systems during the first pandemic phase (March–September 2020) and to identify the strengths, challenges and lessons learned from the perspective of seven participating sentinel sites. Our ultimate aim is to use this information to prepare future integration of COVID-19 and influenza sentinel surveillance and strengthen preparedness. With new SARS-CoV-2 variants emerging worldwide and the relaxation of social and testing measures, the importance of virus detection and characterisation through primary care sentinel surveillance is warranted even more, while ‘the threat of influenza epidemic and pandemics persist’.
This work is licensed under a Creative Commons Attribution 4.0 International License. http://creativecommons.org/licenses/by/4.0/
Bagaria, J., Jansen, T., Marques, D., Hooiveld, M., McMenamin, J., de Lusignan, S., Vilcu, A., Meijer, A., Rodrigues, A., Brytting, M., Mazagatos, C., Cogdale, J., van der Werf, S., Dijkstra, F., Guiomar, R., Enkirch, T., Valenciano, M. & I-MOVE-COVID-19 study team 2022, 'Rapidly adapting primary care sentinel surveillance across seven countries in Europe for COVID-19 in the first half of 2020: strengths, challenges, and lessons learned', Eurosurveillance, 27(26). https://doi.org/10.2807/1560-7917.ES.2022.27.26.2100864