Sentence examples for could have circulated from inspiring English sources
One could argue that some of the pathogens may not be new at all; they could have circulated among humans for centuries and are just being identified for the first time because of increased surveillance and reporting.
Both Group 1 and Group 2 aVDPVs could have circulated in sub-populations with low vaccine coverage, although such pockets have not yet been identified (see example [33]).
Our findings suggest that H3N2 and H1N2 viruses could have circulated for many years in Brazil but were not associated with major clinical illness and have become pathogenic only since 2009, after reassortment with co-circulating pH1N1 virus internal genes.
These results should be interpreted with caution because of known antigenic cross-reactivity of arboviruses, including CHIKV; however, these finding indicate that CHIKV could have circulated in the region and that there may be immunity among some populations.
Since that time, rumors have circulated that BP could cut ties with their CEO.
Following the 1995 destruction by fire of Ambohimanga's sister rova at Antananarivo, widely believed to have been a politically motivated arson, rumors have circulated that Ambohimanga could suffer a similar fate.
Rumors have circulated that the church could close, worrying many in the congregation who see St. Elizabeth as a second home.
"Influenza viruses readily swap genes to generate new viruses, so something like this could happen, especially since many of these viruses have circulated in recent years," Kawaoka said.
This result could indicate that at some point a vaccine-like virus may have circulated in commercial flocks during 2007.
It and several of the claims it contained have circulated for months within newsrooms, including the Guardian's, which resisted their publication until adequate verification could be unearthed.
