Night shift work was not associated with a higher risk of becoming infected. The two together were worse than either alone: night shift workers with chronic insomnia had roughly 2.7 times the risk of day workers without insomnia. Night workers with obesity showed nearly three times the long COVID risk, compared with a much smaller elevation among day workers without obesity. The authors describe their findings as the first to link night shift work to increased long COVID risk. Night shift workers had an 88 percent higher risk of long COVID than day workers, but not a higher risk of contracting the virus.