Ethics approval and consent to participate
Permission of the (guardians of the) cases for diagnostics and sequencing of the human specimens was not required because the GGD has legal permission, provided by Dutch national public health law (Wet Publieke Gezondheid (WPG))[34], to process patient information for surveillance and outbreak analysis of notifiable diseases and can request microbiological laboratories to perform additional testing (including whole genome sequencing) on available clinical materials (article 25 section 5 WPG). Therefore, medical ethical clearance for this study was not required.
Consent for publication
Not applicable, see section ‘Ethics approval and consent to participate’.
Availability of data and materials
The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.
Competing interests
The authors declare that they have no competing interests.
Funding
Deployment and microbiological analysis of the passive samplers described in this study was funded by a sewage consortium consisting of GGD Amsterdam, Amsterdam; GGD Rotterdam, Rotterdam; Erasmus Medical Center, Rotterdam; KWR, Nieuwegein; Partners4UrbanWater, Nijmegen; IMD, Apeldoorn; STOWA, Amersfoort, all in the Netherlands and financially supported by the Water Technology Topconsortium for Knowledge and Innovation. The hours dedicated to this project by the first and third author were funded by the Ministry of Health, Welfare and Sport of the Dutch Government within the program ‘Strengthening infectious disease control and pandemic preparedness of the regional Public Health Services’ in 2023-2024. The Ministry of Health, Welfare and Sport of the Dutch Government had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript.
Authors' contributions
MJ, CW, EF and GM coordinated the investigations of the outbreak. MJ, RS, JL, MS, EF and GM contributed to data collection, case information and data analysis. HV, MW and GM were involved in the laboratory investigations. MJ and MS drafted the manuscript and all authors were involved in revising the manuscript. All authors reviewed and approved the final version.
Acknowledgements
The authors would like to thank the sewage consortium members including M. de Graaf, Erasmus Medical Center, Rotterdam, the Netherlands; P. Bijkerk and G. Sips, GGD Rotterdam, Rotterdam, the Netherlands for their input and feedback during deployment and microbiological analysis of the passive samplers; D. McCarthy, Monash University, Melbourne, Australia, for providing the print code of the passive sampler; J. Cremer and B. van der Veer, RIVM, Bilthoven, the Netherlands, for the sequencing analysis of the human specimens; G. Elsinga, KWR, Nieuwegein, the Netherlands, for the ddPCR analysis; J. Guldemeester, Erasmus Medical Center, Rotterdam, the Netherlands, for providing HAV genome copies to use as positive controls; and N. Khawaja, GGD Amsterdam, Amsterdam, the Netherlands, for providing the case data.