Changes in the frequency of mutations were calculated for all amino acids that were used to calculate changes in thermodynamic stability. For H1N1, HA changes in the frequency of mutations calculated for yearly periods (1 October to 30 September) from 2011 to 2015. For H3N2, HA changes in the frequency of mutations were calculated for yearly periods (1 October to 30 September) from 2010 to 2016. Changes were considered significant if an amino acid frequency changed by greater than 10% from the preceding yea
Flu vaccines work by priming the immune with purified proteins from the outer layer of killed flu viruses. This induces immune cells to make antibodies that stop foreign invaders from infecting cells, readying them to attack flu viruses when the body sees them again. Most flu vaccine proteins are purified from a virus grown in chicken eggs, although a small fraction of flu vaccine proteins are produced in systems that do not involve eggs.
“We have a responsibility to ensure that research with infectious agents is conducted responsibly, and that consider the potential biosafety and biosecurity risks associated with such research,” said NIH director Dr. Francis Collins.
The team showed that antibodies elicited in ferrets and humans exposed to the egg-produced 2016-2017 strain did a poor job of neutralizing H3N2 viruses that circulated last year. However, antibodies elicited in ferrets infected with the current circulating H3N2 viral strain (that contains the new protein) and humans vaccinated with a H3N2 vaccine produced in a non-egg system were able to effectively recognize and neutralize the new H3N2 virus.Keep up to date with the latest news from ScienceDaily via social