During World War II, there were three kinds of potentially useful killed vaccines. All three killed vaccines relied on the cultivation of Rickettsia prowazekii, the organism responsible for typhus. The first attempt at a killed vaccine was developed by Germany, using the Rickettsia prowazekii found in louse feces. The vaccine was tested extensively in Poland between the two world wars and used by the Germans for their troops during their attacks on the Soviet Union.A second method of growing Rickettsia prowazekii was discovered using the yolk sac of chick embryos. Germans tried several times to use this technique of growing Rickettsia prowazekii but no effort was pushed very far.The last technique was an extended development of the previously known method of growing murine typhus in rodents. It was discovered that rabbits could be infected, by a similar process, and contract classical typhus instead of murine typhus. Again, while proven to produce suitable Rickettsia prowazekii for vaccine development, this method was not used to produce wartime vaccines.During WWII, the two major vaccines available were the killed vaccine grown in lice and the live vaccine from France. Neither was used much during the war. The killed, louse-grown vaccine was difficult to manufacture in large enough quantities, and the French vaccine was not believed to be safe enough for use.The Germans worked to develop their own live vaccine from the urine of typhus victims. While developing a live vaccine, Germany used live Rickettsia prowazekii to test multiple possible vaccines capabilities.
Secondary airway malacia was defined as airway malacia secondary to esophageal atresia, VATER/VACTERL association (condition with vertebral anomalies, anal atresia, congenital heart disease, tracheoesophageal fistula or esophageal atresia, renourinary anomalies, or radial limb defects), vascular or other external compression of the airways, or specific syndromes. Treatment
Time
Minimally Invasive, usually in conjunction with Continuous Positive Airflow Pressure. Continuous Positive Airflow Pressure
A method of respiratory ventilation. Tracheotomy
Surgical procedures on the neck to open a direct airway through an incision in the trachea (the windpipe). Prosthesis
Insertion of a prosthesis to keep the bronchial tube open. Notes
References
Carden, KA, Boiselle, PM, Waltz, DA, et al. (2005) Tracheomalacia and tracheobronchomalacia in children and adults: an in-depth review. Chest 127,984-1005. Clements, B Congenital malformations of the lungs and airways. Taussig, LM Landau, LI eds. Pediatric respiratory medicine 1999,1106-1136 Mosby. St. Louis, MO
Austin, J, Ali, T Tracheomalacia and Bronchomalacia in children: pathophysiology, assessment, treatment and anaesthesia management. Paediatr Anaesth 2003;13,3-11
McNamara, VM, Crabbe, DC Tracheomalacia. Paediatr Respir Rev 2004;5,147-154
Benjamin, B Tracheomalacia in infants and children. Ann Otol Rhinol Laryngol 1984;93,438-442


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