In some cases, these vaccines use epitopesâthe very specific parts of the antigen that antibodies or T cells recognize and bind to. Because subunit vaccines contain only the essential antigens and not all the other molecules that make up the microbe, the chances of adverse reactions to the vaccine are lower.
Tornadoes occur in many parts of the world, including Australia, Europe, Africa, Asia, and South America. Even New Zealand reports about 20 tornadoes each year. Two of the highest concentrations of tornadoes outside the U.S. are Argentina and Bangladesh.
Tweet. Tornadoes occur around the world, most notably in the United States, South America and parts of Africa and Asia. One of the key points of activity is a section of the U.S. known as Tornado Alley, which is considered to be where tornadoes are most common. According to the United States National Weather Service, Oklahoma City, Oklahoma, has the dubious honor of having been struck by tornadoes more often than any other city in the U.S., with the count in excess of 100.