In September 2023 the UKHSA announced that the flagship SIREN study is “entering a new phase” of surveillance of respiratory infections in healthcare workers. SIREN 2.0, as the next phase is to be known, begins this month. The SARS-CoV-2 immunity and reinfection (SIREN) study was established at the height of the pandemic in June 2020. It has continually tested healthcare workers across the UK for COVID-19, providing “crucial information” on the virus’ evolution. In winter 2022 testing for influenza and respiratory syncytial virus (RSV) began and will continue this year.  

Informing vaccine understanding 

UKHSA states that the emergence of the BA.2.86 variant has accelerated the autumn vaccine campaign, as we reported recently. SIREN 2.0 testing of healthcare workers, who are a cohort eligible for the vaccine, will inform data on vaccine efficacy and infection-acquired immunity. From the original cohort of 45,000 further participants will be recruited. 

Vital data 

Professor Susan Hopkins, Chief Medical Advisor at the UKHSA thanked the participants in “this crucial study”.  

“It is because of you that we have been able to collect vital data and insights on COVID-19 across the pandemic, furthering our understanding on immune response and the protection offered by vaccines.”  

The next phase of the study will “play a core role in the continued surveillance of COVID-19″, including the detection of new variants, and allow the assessment of the “impact of influenza and RSV on healthcare workers”. Working with partners at the Worldwide Influenza Centre (WIC) at the Francis Crick Institute and the Respiratory Virus and Microbiome Initiative (RVI) at the Wellcome Sanger Institute, the team will “continue to answer the most important questions” on respiratory diseases.  

The Wellcome Sanger Institute will sequence samples provided by the UKHSA, using metagenomics to investigate other pathogens. Influenza virus strains that are identified during the study will be shared with WIC, which may facilitate the design of future influenza vaccines

Maximising the yield of science 

Dr Ewan Harrison is Head of RVI at the Wellcome Sanger Institute and is “excited” to work with the SIREN study to “maximise the yield of science”.  

“The RVI builds on the technology used for the genomic surveillance of SARS-CoV-2 during the pandemic. We hope that by expanding the range of respiratory viruses that are routinely sequenced, we can contribute to scientific understanding that will help prevent and treat infections caused by respiratory viruses.”  

Samples from participants are already being tested in a partnership with the newly established VDEC. This will allow greater understanding of the immune response provided by vaccination and inform the national risk assessment.  

For more on infectious disease surveillance and responses, come to the World Vaccine Congress in Barcelona next month, or subscribe to our weekly newsletters here!