Newly released records from Dr. Anthony Fauci's personal diary indicate Israel played a substantial role in influencing U.S. COVID-19 booster policy, providing early evidence of declining vaccine protection months before comparable American data became available.
The documents, released July 26 by Sen. Rand Paul ahead of Fauci's Senate appearance, reference Israeli studies, health officials and vaccination data repeatedly as the Biden administration weighed whether to recommend a third dose of the Pfizer-BioNTech vaccine. When Fauci testified before the Senate Homeland Security and Governmental Affairs Committee on July 29, he declined to answer lawmakers' questions, invoking his Fifth Amendment right against self-incrimination more than 100 times.
Israel features prominently throughout the more than 1,100 pages of diary entries, referenced dozens of times as American officials consulted Israeli data to understand the evolving pandemic.
By mid-2021, Israel held a unique position in the global pandemic response. Having vaccinated much of its population months before most countries, primarily with Pfizer-BioNTech, it became the first nation able to measure how vaccine protection changed in real-world conditions. Its centralized healthcare system and comprehensive national health databases provided evidence American officials lacked at the time.
On July 6, 2021, Fauci recorded concern over Israeli findings showing vaccine protection against infection had declined sharply with the Delta variant - from approximately 94 percent to about 64 percent. Though protection against severe illness remained high, the decline represented an early indication that immunity might not prove as durable as expected. Fauci noted "a dramatic diminution with the delta variant in protection against infection and symptomatic disease" And observed an increase in hospitalizations in Israel among vaccinated people. He briefed President Biden the same day.
By mid-August, Fauci's diary recorded increasingly urgent concerns over waning immunity. He documented that Israeli officials were reporting "a gradual waning of protection of the Pfizer vaccine over a few months," With protection against infection and mild disease "dramatically diminished," While protection against hospitalization had "also significantly decreased."
The administration advanced toward recommending booster shots despite incomplete American data. The diary notes disagreement among scientists, including vaccine expert Dr. Paul Offit and virologist Dr. Vincent Racaniello, who argued broader evidence was needed before recommending boosters to the general public.
Fauci repeatedly justified the administration's position by referencing Israeli experience. Following discussions with Israeli health officials including Health Ministry Director-General Professor Nachman Ash and others, Fauci concluded Israel's data warranted moving forward. He described Israeli findings as showing gradual vaccine protection decline over several months, with significant protection restoration after a third dose.
"The Israelis have always been about a month or so ahead of the USA," Fauci wrote.
Fauci compared Israeli findings with American evidence, noting "The data from the U.S.A. cohorts was suggesting that but did not definitively show it." He also wrote, "These data are well ahead of the somewhat disjointed data from the CDC."
The diary describes close communication between Fauci and Israeli leadership. Then-Prime Minister Naftali Bennett requested a Zoom meeting seeking Fauci's "opinion and ultimate support" For Israel's booster campaign and later asked for Fauci's cellphone number so he could "intermittently call me for advice." After obtaining State Department approval, Fauci provided his personal number.
Fauci recorded that the eight-month interval for booster recommendations was driven largely by logistical considerations rather than biology or clinical evidence. He expressed frustration with White House officials who publicly described the timeline as dictated by science, writing "That is just not true."
Following one meeting with Israeli experts, Fauci noted that "the people in the White House medical team are all excited now about the Israeli data." During another conversation, Biden reportedly asked Bennett about Israel's booster timeline. According to the diary, "President Biden called me up on my cell phone. He said he was in with the Prime Minister of Israel and the Prime Minister was telling him that Israel will be giving their booster shot at five months." Biden asked whether the United States was following Israel's lead.