Based on a close monitoring of the global situation and the research of our own affiliated faculty and others SFI has decided to suspend visitor-related programs as of today until more complete and reliable information is available on COVID-19. Visitors already en route or in place will continue to be welcome at SFI through to the end of their travel.

This decision is based on the following factors:

1. SFI is a global research network based on close collaboration among teams drawn globally.
2. Physical proximity is the means by which COVID-19 is transmitted.
3. The infectivity of non-symptomatic carriers is unknown but higher than anticipated.
4. The morbidity is unknown but likely to be higher than that of seasonal influenza.
5. Containment and quarantine are the best means of mitigating transmission.

Given these factors and all of the uncertainty around them the precautionary principle urges us to suspend events and programming through at least mid-May (including the May Science Board/Trustees symposium). This will come as no surprise to the world and our research colleagues who have undertaken equally forceful measures.

We shall revisit this policy within two months or in mid-May when the data will be exponentially better.

David Krakauer.