chris smyth but these issues with different types of fact see the county authorities really have the luxury of waiting for that they just have to take as you said what's available and go on with it as opposed to waiting for the perfect vaccine for the circumstances is quite right and here we are with the world paralyzed by a pandemic and we want to get back to us and in normal as we possibly can as soon as we can and what is holding the process up at the moment is just that there is difficulty making enough vaccine we're talking about vaccinating an entire world population some vaccines are going to be much more useful in certain settings and by that i mean if you've got a vaccine that needs to be kept at minus 80 degrees it won't be any use whatsoever in a country that doesn't even have a reliable electricity supply let alone minus 80 degree freezers similarly if you have a vaccine which is very very good at surviving in the field but might be a little bit less efficacious then that's actually arguably a much better benefit and a much better prospect to use that in a poor country wh