Online respondent-driven detection for enhanced contact tracing of close-contact infectious diseases: benefits and barriers for public health practice (preprint)

Background: Online respondent-driven detection (online-RDD) is a novel method of case-finding that can enhance contact tracing. However, the advantages and challenges of online-RDD for contact tracing (CT) have not yet been investigated from the perspective of public health professionals (PHPs). Therefore, it remains unclear if, and under what circumstances, PHPs are willing to apply online-RDD for contact tracing. Methods: First, between March and April 2019, we conducted semi-structured interviews with Dutch PHPs responsible for CT in practice. Questions were derived from the diffusion of innovations theory. Second, between May and June 2019 we distributed an online questionnaire to 260 Dutch PHPs to quantify the main qualitative findings. Using hypothetical scenarios that involved close-contact pathogens (scabies, shigella, and mumps), we assessed anticipated advantages and challenges of online-RDD and PHPs intention to apply online-RDD for contact tracing. Results: Twelve interviews were held and 70 PHPs filled in the online questionnaire. A majority of questionnaire respondents (71%) had a positive intention towards using online-RDD for contact tracing. Anticipated advantages of online-RDD were related to accommodating easy and autonomous participation in contact tracing of patients and contact persons, and reaching contact persons more efficiently. Anticipated challenges with online-RDD were related to limited opportunities for PHPs to support, motivate, and coordinate the execution of contact tracing, adequately conveying measures to patients and contact persons, and anticipated unrest among patients and contact persons. Online-RDD was considered more applicable when patients and their contact persons are reluctant to share sensitive information directly with PHPs, digitally skilled and literate persons are involved, and the scope of contact tracing is large. Online-RDD was considered less applicable when consequences of missing information or individuals are severe for individuals - or public health, when measures that patients and contact persons need to undertake are complex or impactful, and when a disease is perceived as particularly severe or sensitive by patients and their contact persons. Conclusions: PHPs generally perceived online-RDD as beneficial to public health practice. The method can help overcome challenges present in regular CT and could be used during outbreaks of infectious diseases that spread via close-contact, such as the SARS-CoV-2 virus. We propose a staggered implementation study to further investigate the application of online-RDD for enhanced CT during the ongoing COVID-19 pandemic.

Assessing training needs in infectious disease management at major ports, airports and ground-crossings in Europe (preprint)

Background: The implementation of core capacities as stated in the International Health Regulations (IHR) is far from complete, and, as the COVID-19 pandemic shows, the spreading of infectious diseases through points of entry (POEs) is a serious problem. To guide training and exercises, we performed a training needs assessment on infectious disease management among professionals at European POE. Methods: We disseminated a digital questionnaire to representatives of designated airports, ports, and ground-crossings in Europe. Topics were derived from the IHR core capacities for POEs. Based on the importance (4-point Likert scale) and training needs (4-point Likert scale), we identified the topics with the highest priority for training. These results were put in further perspective using prior experience (training <3 year, exercise <5 years, events <5 years). Also, preferences for training methodologies were assessed. Results: Fifty questionnaires were included in the analyses, representing 50 POEs from 19 European countries. Importance is high for 26/30 topics, although scores widely vary among respondents. Topics with a high training need (16/30) are amongst others the handling of ill travelers; using and composing the public health emergency contingency plan, and public health measures. Respondents from ports and airports attribute equal importance to most topics, but respondents from ports showed higher training needs on 75% of the topics. POEs are unevenly and generally little experienced. The most preferred training methods were presentations. Simulation is the preferred methodology for training the handling of ill or exposed travelers. Conclusions: The European workforce at designated ports, airports and ground-crossings has a different level of experience and perceives varying importance of the topics assessed in our study. We identified the topics on which training is required. We call for European collaboration between POEs to agree upon the importance of infectious disease management, and to jointly build a trained and prepared workforce that is ready to face the next crisis.  

COVID-19 in healthcare workers in three hospitals in the South of the Netherlands, March 2020 (preprint)

Background: Ten days after the first reported case of SARS-CoV-2 infection in the Netherlands, 3.9% of healthcare workers (HCWs) in nine hospitals located in the South of the Netherlands tested positive for SARS-CoV-2 RNA. The extent of nosocomial transmission that contributed to the HCW infections was unknown. Methods: We combined epidemiological data, collected by means of structured interviews of HCWs, with whole genome sequencing (WGS) of SARS-CoV-2 in clinical samples from HCWs and patients in three of nine hospitals that participated in the HCW screening, to perform an in-depth analysis of sources and modes of transmission of SARS -CoV-2 in HCWs and patients. Results: A total of 1,796 out of 12,022 HCWs (15%) of the three participating hospitals were screened, based on clinical symptoms, of whom 96 (5%) tested positive for SARS-CoV-2. We obtained complete genome sequences of 50 HCWs and 18 patients. Most sequences grouped in 3 clusters, with 2 clusters displaying local circulation within the region. The observed patterns are most consistent with multiple introductions into the hospitals through community acquired infections, and local amplification in the community. Conclusions: Although direct transmission in the hospitals cannot be ruled out, the data does not support widespread nosocomial transmission as source of infection in patients or healthcare workers.

Rapid SARS-CoV-2 whole genome sequencing for informed public health decision making in the Netherlands (preprint)

SARS-CoV-2 is a novel coronavirus that has rapidly spread across the globe. In the Netherlands, the first case of SARS-CoV-2 has been notified on the 27th of February. Here, we describe the first three weeks of the SARS-CoV-2 outbreak in the Netherlands, which started with several different introductory events from Italy, Austria, Germany and France followed by local amplification in, and later also, outside the South of the Netherlands. The timely generation of whole genome sequences combined with epidemiological investigations facilitated early decision making in an attempt to control local transmission of SARS-CoV-2 in the Netherlands.