By Jennifer Rigby LONDON (Reuters) – The Omicron variant of coronavirus is less likely to cause long COVID than previous variants, according to the first peer-reviewed study of its kind from the United Kingdom. Researchers at King’s College London, using data from the ZOE COVID Symptom study app, found the odds of developing long COVID after infection were 20% to 50% lower during the Omicron wave in the UK compared to Delta. The figure varied depending on the patient’s age and the timing of their last vaccination. Long COVID, which includes prolonged symptoms ranging from fatigue to ‘brain fog…