way. it was a bold trial that took a look at getting groups of people who were exposed to the people who were infected, the contacts and the contacts and the contacts and to vax name p nate them a ring way, which is similar to somehow the smallpox vaccine approach was done for the elimination of smallpox. in this study, people were randomized to either get the vaccine right away in the first ring or delay the 21 days and when you compared the people who were in the immediate vaccination around that index case versus those who delay vaccination there were 17 infections in those who delayed and no infection in those who got the vaccine right away. that's an impressive result. >> the is vaccine suitable for everyone? >> yes. it's being done in safety