(Reuters) -The U.S. health regulator said on Thursday it was limiting the use of Johnson & Johnson’s COVID-19 vaccine for adults due to the risk of a rare blood clotting syndrome, the latest setback to the shot that has been eclipsed by rivals. The J&J shot, which received U.S. clearance in February 2021 for adults, can be administered in cases where authorized or approved COVID-19 vaccines are not accessible or if an individual is less keen on using the other two shots, the Food and Drug Administration said. J&J is one of the three vaccines in use in the United States. The other two are from …