The conundrum of faster progression of disease without any signs or symptoms was disturbing. If what they found in the lab was correct, then the virus would have been able to spread without warning and as such could be ubiquitous in the region. The team then sought to learn just how widespread CRF02_AG/A was in the community. Their results confirmed their concern.
They examined samples from three distinct regions of Siberia: Novosibirsk, close to where Vector is located; Novokuznetsk, which is in the nearby federal subject of Kemerovo; and Chita, which is on the Eastern rim of Siberia and borders China and Mongolia. The CRF02_AG/A strain was present in both Novosibirsk and Novokuznetsk, although it was dominant only in the former. In contrast, there was no sign of the virus in the city of Chita; it appeared to be strain-free. This somewhat positive outcome was overshadowed by the fact that in Novosibirsk, over 70% of the cases were found to be positive for this strain.
With the data from Novosibirsk in hand, the team tried to work backwards to identify if there was a risk group associated with the spread, such as heterosexual activity, homosexual activity and injection drug use. What came back in the medical records was even more problematic; there was no specific risk associated with infection. The virus has become homogeneous in the population and due to its physical properties, was continuing to spread unsuspectingly from person to person.
As to how this type of spread could have happened, there were few answers. The only real clue was the fact that several of the Novosibirsk samples positive for CRF02_AG/A came from the penitentiary system. Unfortunately, Novosibirsk has one of the highest prison densities in the entire country so no link could be made with any confidence. If there had been a link to one specific group, such as female sex workers or injection drug users, the people at Vector would have found it.