The Invasive Respiratory Infection Surveillance (IRIS) Initiative reveals significant reductions in invasive bacterial infections during the COVID-19 pandemic

Background Streptococcus pneumoniae, Haemophilus influenzae and Neisseria meningitidis are leading causes of invasive diseases including bacteraemic pneumonia and meningitis, and of secondary infections post-viral respiratory disease. They are typically transmitted via respiratory droplets. We investigated rates of invasive disease due to these pathogens during the early phase of the COVID-19 pandemic. Methods Laboratories in 26 countries across six continents submitted data on cases of invasive disease due to S pneumoniae, H influenzae and N meningitidis from 1 January 2018 to 31 May 2020. Weekly cases in 2020 vs 2018-2019 were compared. Streptococcus agalactiae data were collected from nine laboratories for comparison to a non-respiratory pathogen. The stringency of COVID-19 containment measures was quantified by the Oxford COVID-19 Government Response Tracker. Changes in population movements were assessed by Google COVID-19 Community Mobility Reports. Interrupted time series modelling quantified changes in rates of invasive disease in 2020 relative to when containment measures were imposed. Findings All countries experienced a significant, sustained reduction in invasive diseases due to S pneumoniae, H influenzae and N meningitidis , but not S agalactiae , in early 2020, which coincided with the introduction of COVID-19 containment measures in each country. Similar impacts were observed across most countries despite differing stringency in COVID-19 control policies. There was no evidence of a specific effect due to enforced school closures. Interpretation The introduction of COVID-19 containment policies and public information campaigns likely reduced transmission of these bacterial respiratory pathogens, leading to a significant reduction in life-threatening invasive diseases in many countries worldwide. ### Competing Interest Statement The German Reference Center for Streptococci receives financial support from Pfizer and Merck. MC has previously received a professional fee from Pfizer (Ireland), an unrestricted research grant from Pfizer Ireland (2007-2016) and an Investigator Initiated Reward from Pfizer Ireland in 2018 (W1243730). HH has received research funds from Astellas and Pfizer and a professional fee from Pfizer. The funders had no role in the collection, analysis, interpretation of data or in the writing of and decision to submit the article for publication. ### Funding Statement The infrastructure for the IRIS initiative was funded by a Wellcome Trust Investigator Award to ABB (grant number 206394/Z/17/Z) and a Wellcome Trust Biomedical Resource Grant to MJCM, ABB and KAJ (grant number 218205/Z/19/Z). The German National Reference Laboratory for Meningococci and Haemophilus influenzae is supported by the Robert Koch Institute with funds from the Federal Ministry of Health (funding code 1369-237). The Irish Meningitis and Sepsis Reference Laboratory has received support from Childrens Health Ireland at Temple Street, the Royal College of Surgeons in Ireland, Health Protection Surveillance Centre and the SpID-Net project, which has received funding from the European Centre for Disease Prevention and Control (ECDC) and Horizon 2020. The Polish data collection was partially supported by the Ministry of Health within the framework of the National Programme of Antibiotic Protection (NPOA) and by the Ministry of Science and Higher Education (Mikrobank 2 Programme). Funding for materials, equipment and human resources associated with the laboratory in Catalonia, Spain was provided by Agencia de Salut Publica de Catalunya and Sant Joan de Deu Foundation. BHN has received funding from the Knut and Alice Wallenberg Foundation, the Swedish Research Council and Region Stockholm. The funders had no role in the collection, analysis, interpretation of data or in the writing of and decision to submit the article for publication. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Prof Kevin Marsh is the chair of OxTREC, the University of Oxford ethical committee that considers health related research conducted by Oxford-associated researchers where the research is primarily conducted outside of the UK. He confirmed that OxTREC would not require this study to go through ethical review, because it involves routine surveillance and no possibility of individual patients being identified. Prof Marsh also stated that this is the view that is taken by other ethical committees that he is familiar with. All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes A list of anonymised cases with sampling dates is available upon request. OxCGRT data are publicly available and found here: Google Mobility Reports data are publicly available and found here: