Chicken counting

An AIDS vaccine is heading for clinical trials in South Korea. It was developed at the University of Western Ontario. Dr. Yong Kang heads the group and of course he also does work on VSV. Of course, as this article in The National Post quoting our very own Dr. Earl Brown says "Don't count your chickens." In regards to his hopes for this vaccine. Apparently the quote ends there. The question remains, I guess, are we allowed to count them after they have hatched? The timeline suggests using the vaccine in uninfected people within 6 years.