Today the Advisory Committee on Immunization Practices (ACIP) to the Centers for Disease Control and Prevention (CDC) discussed the continued use of the Johnson & Johnson (J&J) COVID-19 vaccine, after reports of blood clots related to vaccination have risen.ACIP unanimously voted to say mRNA vaccines are preferred over the use of the J&J vaccine for all persons 18 and older in the United States.The preferred recommendation language was the attempt of ACIP members to thread the needle between two uncomfortable realities: mRNA vaccines appear to have fewer serious side effects than J&J and offer longer-lasting protection, but some Americans will not get mRNAs, and some populations, including the homeless and migrant workers, are better served