The phrase 'has been focal' is correct and can be used in written English
You can use it when you want to say that something has been the main or main focus of attention or importance. For example, "In the last few months, education reform has been a focal issue in the national debate."
Although the occurrence of such uncommon G types, except for G9, has been focal, still, in order to "be ready and prepared", we have constructed and characterized eight additional reassortant rotavirus vaccines, each of which bears a single human or bovine VP7 gene encoding G serotype 5, 8, 9 or 10 specificity and the remaining 10 genes of RRV strain MMU18006 or bovine rotavirus strain UK.
Debates have been focal points of the Republican campaign to a greater degree than they were in 2007 and 2008.
Italian and Spanish stocks also advanced after surveys showed that manufacturing activity rose in the two countries, which are in recession and have been focal points of Europe's debt crisis.
Both sit in areas that Israel controls and that the Palestinians demand as part of the territory of a future state, and both have been focal points of past violence.
The statistical tests for disturbance rate were conservatively conducted at the level of the individual: each member of the Colchester community that had been focal sampled and had performed the gesture provided a distinct data point for the analyses.
Turkey Hill has been the focal point of my whole career.
Beason has been the focal point in the change.
Chilled meat has been the focal point of Abu Ghazaleh's quagmire.
With the absence of Hill, Jerry Stackhouse has been the focal point in the Pistons' defense.
Despite that success, Rodriguez has been a focal point for criticism and self-imposed drama.
And Diallo, the league's leading scorer two years ago in Tampa Bay, has been the focal point on offense.
