Thermo stability study of Temevac® I-2 Newcastle vaccine
Newcastle is a highly contagious disease of domestic poultry and wild birds and is widely regarded as the most important avian disease. Effective Newcastle vaccines are crucial for control of the disease. The objective of this study was to establish the stability of TEMEVAC® (I-2) vaccine at three different temperatures for 204 days. The study was conducted at Tanzania Vaccine Institute laboratories for the period of April-December 2017. Two vaccine batches (Batch 0068 and 0069) were subjected at 37°C for 10 days, 22-25°C for 60 days and 2-8°C for 204 days. The vaccines were 10-fold serial diluted and then inoculated into 9-days old embryonated chicken eggs and incubated for 96 hours. A virus infectivity assay and Standard mathematical technique were applied to confirm the presence and measure the amount of live Newcastle virus in the suspension. The study revealed that TEMEVAC® can maintain potency up to more than10 days, 45 days and 197 days at 37°C, 22-45°C and 2-8°C, respectively. This study underscores the importance of using TEMEVAC® vaccine which can tolerate relatively wider range of temperatures for control of the disease in rural areas.
Keywords: local chickens, Thermotolerant vaccine, Newcastle disease