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Because certain viruses and bacteria evolve to become resistant to the old vaccines.

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13y ago

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Why don't you need other vaccines every year?

Because some vaccination are unimportant.


Why are flue vaccines given each year?

because the influenza bug changes every year. It's never exactly the same as the previous year.


Do vaccines exist?

Yes, in fact many different vaccines exist for many different diseases (in the case of flu a new vaccine has to be made every year because the virus evolves so rapidly that the previous year's vaccine would not work against it).


How many children die from vaccines each year?

i will say about 50,000 children die each year from vaccines


When do struts on a Toyota Sequoia need to be changed?

The struts need to be changed every other year.


Was the Jewish Temple veil ever changed?

Every year.


When were vaccines created?

In the year 1796.


What cultural things are changed every year?

food shelter clothing


How did the vaccination change society?

Vaccines changed society because with out vaccines then there would be so many deaths. Vaccines help to prevent the disease before you get it. Why pay a visit to the doctor when you can just go get the vaccine and not have to get the disease.


Should you take your dogs to get vaccinated once a year or every three years?

To keep your dog's vaccines updated and protected from disease, take your dog for it's injection once a year.


Who were the two consuls during the first punic war?

The first two consuls during the first Punic war were Lucius Megellus and Quintus Vitulus. They were the first two. Remember that the consuls changed every year, so unless there was a dictator appointed the consuls changed annually and there were generally two new consuls for every year of the war.The first two consuls during the first Punic war were Lucius Megellus and Quintus Vitulus. They were the first two. Remember that the consuls changed every year, so unless there was a dictator appointed the consuls changed annually and there were generally two new consuls for every year of the war.The first two consuls during the first Punic war were Lucius Megellus and Quintus Vitulus. They were the first two. Remember that the consuls changed every year, so unless there was a dictator appointed the consuls changed annually and there were generally two new consuls for every year of the war.The first two consuls during the first Punic war were Lucius Megellus and Quintus Vitulus. They were the first two. Remember that the consuls changed every year, so unless there was a dictator appointed the consuls changed annually and there were generally two new consuls for every year of the war.The first two consuls during the first Punic war were Lucius Megellus and Quintus Vitulus. They were the first two. Remember that the consuls changed every year, so unless there was a dictator appointed the consuls changed annually and there were generally two new consuls for every year of the war.The first two consuls during the first Punic war were Lucius Megellus and Quintus Vitulus. They were the first two. Remember that the consuls changed every year, so unless there was a dictator appointed the consuls changed annually and there were generally two new consuls for every year of the war.The first two consuls during the first Punic war were Lucius Megellus and Quintus Vitulus. They were the first two. Remember that the consuls changed every year, so unless there was a dictator appointed the consuls changed annually and there were generally two new consuls for every year of the war.The first two consuls during the first Punic war were Lucius Megellus and Quintus Vitulus. They were the first two. Remember that the consuls changed every year, so unless there was a dictator appointed the consuls changed annually and there were generally two new consuls for every year of the war.The first two consuls during the first Punic war were Lucius Megellus and Quintus Vitulus. They were the first two. Remember that the consuls changed every year, so unless there was a dictator appointed the consuls changed annually and there were generally two new consuls for every year of the war.


What year was the winter olympic rotation changed from the original format summer and winter in the same year?

1992 was the last year of both olympic games in the same calender year. The winter Olympics were changed to 1994 and then every four years again in rotation. You now have an olympic games every 2 years.