New York: FDA plans to warn that the J & J vaccine can cause an increase in the risk of rare neurological conditions known as the Guillain-Barré syndrome, another setback for vaccines is largely ruled out in the US because of the problem of manufacturing and while the security break earlier this year, said the source , Although the regulator has found that opportunities to develop low conditions, they seem to be three to five times higher among J & J shot recipients rather than among the general population in the US, the sources said.