Ricin chain A. This vaccination is effective for several months due to the body's production of antibodies to the foreign protein. In 1978 Bulgarian defector Vladimir Kostov survived a ricin attack similar to the one on Georgi Markov, probably due to his body's production of antibodies. When a ricin-laced pellet was removed from the small of his back it was found that some of the original wax coating was still attached. For this reason only small amounts of ricin had leaked out of the pellet, producing some symptoms but allowing his body to develop immunity to further poisoning. The seeds of
London Buses route 7 and London Bridge station. This route disappeared later in 1916 owing to Wartime shortages, but reappeared on 30 April 1917. During the 1920s, route 7 was extended to Acton and a 7B was introduced as a Waterloo station to London Bridge, Monday to Friday peak hours only service via Holborn. On 1 December 1924, a new system of route numbering on London buses came into force under The London Traffic Act 1924. This gave the Metropolitan Police responsibility for bus operation and route numbering. Route 7 remained unchanged; the 7A was renumbered 107, and the 7B to 166. Short workings