An experimental tuberculosis (TB) vaccine may provide a way to enhance
protective effects of the BCG TB vaccine, which is widely used but offers
limited protection for adults, reported researchers from England and Belgium
in the November Nature Medicine.
The researchers found that the candidate vaccine, a modified vaccinia
virus expressing a TB bacterial antigen, induced an immune response (indicated
by high levels of interferon-gamma-secreting antigen-specific T cells) in
volunteers who had never been vaccinated. Volunteers who had previously received
the BCG vaccine had substantially stronger responses, and at 24 weeks after
vaccination, these levels were 5 to 30 times greater than those of vaccinees
given a single BCG vaccination.
Stephenson J. TB Vaccine Boost. JAMA. 2004;292(19):2329. doi:10.1001/jama.292.19.2329-d