US Will Begin Third Dose on September 20

STUDIES SHOW THAT VACCINE EFFECTIVENESS DECREASES OVER TIME

El Comercio de Colorado Newsroom

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The federal government of the United States will administer the third COVID-19 vaccine September 20. Those who have received the second injection of Pfizer or Moderna eight months prior can be vaccinated as of that date. Health authorities have made this decision due to the observed reduction in the effectiveness of vaccines over time due to the delta variant.

US Surgeon General Vivek Murthy, a spokesman for the federal administration on public health, noted that “recent data makes it clear that protection against mild and moderate disease diminishes over time. This is likely due to a decline in immunity and the growth of the delta variant,” explained Murthy of the White House pandemic response team.

Effectiveness Decreases Over Time

Experts emphasized that the data confirms that both doses of vaccines are effective against severe forms of COVID. However, Murthy remarked that a third dose is recommended because there is concern that the protection will end up diminishing even in severe cases. According to the CDC Director, Rochelle Walensky, studies indicate that the effectiveness of vaccines decreases over time.

“Although our vaccines are currently working well enough to prevent hospitalizations, we are seeing concerning evidence of a decline in vaccine effectiveness over time. Additionally, there are international reports, such as in Israel, showing vaccinated persons contracting COVID with severe symptoms,” said Walensky.

Aplicarán tercera dosis desde 20 de septiembre

Fauci’s Message

Faced with this risk, the government’s main epidemiologist, Anthony Fauci, clarified that the levels of antibodies in vaccinated people decrease over time. “Higher levels of antibodies are associated with higher levels of vaccine efficacy,” said Fauci while considering the possibility that greater protection against the delta variant requires more antibodies.

“And a boost in immunization with messenger RNA (the technology used to develop the Pfizer and Moderna vaccines),” he added, “multiplies antibody levels at least tenfold and probably more.” The US also anticipates that those who have received the Johnson & Johnson (J&J) vaccine, which is a single dose, may need an additional injection.

Pfizer and Moderna use messenger RNA technology, a kind of code that the vaccine delivers to cells. This code serves as an instruction manual for the vaccinated person’s immune system so that the body recognizes the coronavirus and attacks it. Serums like J & J’s use an adenovirus, a “deactivated” virus, that sends instructions to the vaccinated body to fight COVID-19.