Given how rare the blood clotting event is, right now thought to be less than one in a million, individuals who received the Johnson & Johnson vaccine should be aware but recognize it is extremely unlikely they will be affected. In the first one to four days after vaccination, vaccinated persons should anticipate the known side effects from this vaccine—including the low-grade fever, chills, aches, mild headache, injection site soreness. These are expected and not the symptoms associated with these rare clotting events. Symptoms of concern occur anywhere from five days to three weeks after vaccination, and include severe headache with or without vomiting, any new neurologic or stroke-like symptoms, or other new symptoms including easy bruising, red dot-like rash, severe abdominal pain, and trouble breathing.