A standardized instrument quantifying risk factors associated with bi-directional transmission of SARS-CoV-2 and other zoonotic pathogens: The COVID-19 Human-Animal Interactions Survey (CHAIS)

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SARS-CoV-2 (CoV-2), which surfaced in late 2019 in Wuhan City, China, most likely originated in bats and rapidly spread among humans globally, harming and disrupting livelihoods worldwide. Early into the pandemic, reports of CoV-2 diagnoses in pets and other animals emerged, including dogs, cats, farmed mink and some large felids (tigers and lions) from various countries. While most CoV-2 positive animals were confirmed to have been in close contact with CoV-2 positive humans, there has been a paucity of published evidence to-date describing risk factors associated with CoV-2 transmission among humans and domestic and wild animals. The COVID-19 Human-Animal Interactions Survey (CHAIS) was developed through a cross-CEIRS Center collaboration to provide a standardized survey describing human-animal interaction during the pandemic and to evaluate behavioral, spatiotemporal, and biological risk factors associated with bi-directional zoonotic transmission of CoV-2 within households and other shared environments. CHAIS measures four broad domains of transmission risk; 1) intensity and risk of infection among human hosts, 2) spatial characteristics of shared environments, 3) behaviors and human-animal interactions, and 4) animal susceptibility to infection and propensity for onward spread. Following the development of CHAIS, with a One Health approach, a multidisciplinary group of experts (n=20) was invited to review and provide feedback on the survey for content validity. Expert feedback was incorporated into two final survey formats-a long-form and an abridged version for which specific core questions addressing zoonotic and reverse zoonotic transmission were identified. Both forms are modularized, with each section having the capacity to serve as independent instruments, allowing researchers to customize the survey based on context and research-specific needs. Further adaptations for studies seeking to investigate other zoonotic pathogens with similar routes of transmission (i.e. respiratory, direct contact) are also possible. The CHAIS instrument is a standardized human-animal interaction survey developed to provide important data on risk factors that guide transmission of CoV-2 from humans to animals, with great utility in capturing information of zoonotic transmission risk factors for CoV-2 and other similar pathogens.


  • We present a standardized survey instrument for evaluating risk factors associated with bi-directional zoonotic transmission of SARS-CoV-2 and other similarly transmitted pathogens in household and other settings where humans and animals share close contact.

  • The CHAIS instrument evaluates behavioral, spatiotemporal, and host determinants of transmission risk of SARS-CoV-2 and is highly adaptable for use in studies seeking to investigate other zoonotic pathogens such as influenza viruses.

  • This standardized instrument will enable pooling of data across studies for meta-analyses to improve predictive models of bi-directional transmission of SARS-CoV-2 among humans and animals and will inform public health prevention and mitigation measures.

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  1. SciScore for 10.1101/2021.09.21.21263227: (What is this?)

    Please note, not all rigor criteria are appropriate for all manuscripts.

    Table 1: Rigor

    Ethicsnot detected.
    Sex as a biological variablenot detected.
    Randomizationnot detected.
    Blindingnot detected.
    Power Analysisnot detected.

    Table 2: Resources

    No key resources detected.

    Results from OddPub: We did not detect open data. We also did not detect open code. Researchers are encouraged to share open data when possible (see Nature blog).

    Results from LimitationRecognizer: We detected the following sentences addressing limitations in the study:
    Researchers should take into consideration the current limitations of antibody testing, including type of immunoglobulin detection, evolving knowledge of immune response and antibody duration in humans and animals, and accuracy of tests, among others (Mathur & Mathur, 2020; Özçürümez et al., 2020; Theel et al., 2020). Researchers also should consider vaccination status of people and animals and are encouraged to add questions as needed in this regard. Finally, studies conducted in households or other environments (such as zoos) where infected humans have similarly reported interactions with multiple animal species, may build upon laboratory animal model studies by elucidating natural-world differences in susceptibility and transmission patterns. CHAIS as a standard instrument for other zoonotic pathogens: The CHAIS instrument was specifically designed to be adapted to support studies investigating zoonotic and reverse zoonotic transmission of CoV-2 and similarly transmitted pathogens in settings where animals and humans share close contact, such as zoonotic strains of influenza viruses, Chlamydophila felis, Bordetella bronchiseptica, Y. pestis, Streptococcus group A, and methicillin-resistant Staphylococcus aureus (MRSA), among others (Davis et al., 2012; Defres, Marwick, & Nathwani, 2009; Loeffler A, 2011; Manian, 2003; Rubinstein, Kollef, & Nathwani, 2008; Shrikrishna D, 2009; Trujillo J, 2012). While there may be important pathological and immunological differences between...

    Results from TrialIdentifier: No clinical trial numbers were referenced.

    Results from Barzooka: We did not find any issues relating to the usage of bar graphs.

    Results from JetFighter: We did not find any issues relating to colormaps.

    Results from rtransparent:
    • Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
    • Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
    • No protocol registration statement was detected.

    Results from scite Reference Check: We found no unreliable references.

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