U.S. news outlets say the Biden administration will begin urging all Americans who have been fully vaccinated against COVID-19 to get an additional shot. The added dose is intended to offer more protection against the highly contagious delta variant that has led to a wave of new infections.Federal health officials are expected to announce sometime this week that Americans should get the extra shot, commonly known as a booster, eight months after their initial inoculation. Most Americans received either the two-dose Pfizer or Moderna vaccines, while some were given the Johnson & Johnson single-dose vaccine.Officials had been rejecting calls to authorize booster shots of COVID-19 vaccines saying data suggested that people are still protected from the virus, including the delta variant. But new studies out of Israel show the Pfizer vaccine’s effectiveness had significantly decreased among elderly people who were inoculated at the beginning of this year. The data prompted Israel to begin administering booster shots to people 50 years or older.The booster shots will likely begin sometime in September after the Food and Drug Administration approves Pfizer’s request to use the vaccine for a third dose. The first to receive the booster will be health care workers, nursing home residents and other elderly people — the same groups that received the first shots in the U.S.CNN says experts anticipate the policy will be extended to those who received the one-dose Johnson & Johnson vaccine, once they have more data.Both the FDA and the Centers for Disease Control last week recommended a third shot of Pfizer or Moderna for some people with weakened immune systems.Some information for this report came from the Associated Press. 
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