A "positive" result was represented by clumping of bacteria, indicating that the body was producing anti-serum (now called antibodies) against the pathogen.Citing the example of the Second Boer War, during which many soldiers died from easily preventable diseases, Wright convinced the British Army that 10 million vaccine doses should be produced for the troops being sent to the Western Front, thereby saving up to half a million lives during World War I. The British Army was the only combatant at the outbreak of the war to have its troops fully immunized against the bacterium. For the first time, their casualties due to combat exceeded those from disease.In 1909, Frederick F. Russell, a U.S. Army physician, adopted Wrights typhoid vaccine for use with the Army, and two years later, his vaccination program became the first in which an entire army was immunized. It eliminated typhoid as a significant cause of morbidity and mortality in the U.S. military. Typhoid vaccination for members of the American military became mandatory in 1911. Before the vaccine, the rate of typhoid fever in the military was 14,000 or greater per 100,000 soldiers.
However, the dosage used in the Phase III trial may have been too low to be efficacious.A Phase II study with maribavir demonstrated that prophylaxis with maribavir displayed strong antiviral activity, as measured by statistically significant reduction in the rate of reactivation of CMV in recipients of hematopoietic stem cell/bone marrow transplants. In an intent-to-treat analysis of the first 100 days after the transplant, the number of subjects who required pre-emptive anti-CMV therapy was statistically significantly reduced with maribavir compared to placebo.ViroPharma conducted a Phase III clinical study to evaluate the prophylactic use for the prevention of cytomegalovirus disease in recipients of allogeneic stem cell transplant patients. In February 2009, ViroPharma announced that the Phase III study failed to achieve its goal, showing no significant difference between maribavir and a placebo at reducing the rate at which CMV DNA levels were detected in patients.The safety and efficacy of maribavir were evaluated in a Phase III, multicenter, open-label, active-controlled trial that compared maribavir with a treatment assigned by a researcher running the study, which could include one or two of the following antivirals used to treat cytomegalovirus: ganciclovir, valganciclovir, foscarnet, or cidofovir. In the study, 352 transplant recipients with cytomegalovirus infections who did not respond (with or without resistance) to treatment randomly received maribavir or treatment assigned by a researcher for up to eight weeks. The study compared the two groups plasma cytomegalovirus DNA concentration levels at the end of the studys eighth week, with efficacy defined as having a level below what is measurable.