Susan Monarez, the director of the U.S. Centers for Disease Control and Prevention, is being ousted from her role less than a month after the Senate confirmed her to lead the public health agency, the White House confirmed to CBS News.

The Department of Health and Human Services announced in an X post Wednesday that Monarez no longer leads the CDC. Reports on her ouster were immediately followed by a dispute between the administration and her attorneys regarding whether she had been legally fired, with lawyers for Monarez arguing she’s still in charge of the CDC and only President Trump can fire her.

It’s not clear why Monarez was removed from the job — but several other top CDC officials resigned Wednesday, often citing disagreements with the Trump administration over its vaccine policy, budgets cuts to the agency, and what one described as the “weaponization of public health.”

Prominent D.C.-based attorney Mark Zaid said in a statement that Monarez “has neither resigned nor received notification from the White House that she was fired.” He said that he and lawyer Abbe Lowell are representing Monarez.

Zaid alleged that Monarez was “targeted” because she “refused to rubber-stamp unscientific, reckless directives and fire dedicated public health experts.”

White House spokesman Kush Desai alleged in response that Monarez was terminated because she “refused to resign despite informing HHS leadership of her intent to do so.”

“As her attorney’s statement makes abundantly clear, Susan Monarez is not aligned with the President’s agenda of Making America Healthy Again,” Desai said in response to Zaid’s initial statement.

Hours later, Zaid and Lowell said Monarez was told of her firing Wednesday night by a “White House staffer in the personnel office.” In a statement to CBS News, they called the move “legally deficient” and argued that she remains the leader of the CDC because, as a presidential appointee, “only the president himself can fire her.” 

On Monday, Monarez had to cancel an agency-wide meeting because she had been summoned to Washington, D.C., according to CDC officials.

In its X post, HHS thanked Monarez “for her dedicated service for the American people,” and said Secretary of Health and Human Services Robert F. Kennedy Jr. “has full confidence in his team” at the CDC.

At least three other senior CDC leaders have resigned from the agency, according to resignation emails obtained by CBS News.

Daniel Jernigan, who led the CDC’s National Center for Emerging and Zoonotic Infectious Diseases, told colleagues he was leaving due to “the current context in the Department.” The CDC’s Chief Medical Officer Debra Houry and the head of the National Center for Immunization and Respiratory Diseases, Demetre Daskalakis, also announced their departures.

Houry’s message to CDC staffers warned about the “rise of misinformation” about vaccines. She also argued planned cuts to the agency’s budget will hurt the CDC.

“For the good of the nation and the world, the science at CDC should never be censored or subject to political pauses or interpretations,” wrote Houry, who worked at the CDC for over a decade. “Vaccines save lives—this is an indisputable, well-established, scientific fact.”

Daskalakis said in a note to CDC staff: “I am not able to serve in this role any longer because of the ongoing weaponizing of public health.”

Daskalakis also posted on X a resignation letter addressed to Houry, in which he criticized recent changes to vaccine recommendations and warned of an “intentional eroding of trust in low-risk vaccines.” He also said Kennedy and his staff’s views “challenge my ability to continue in my current role at the agency.”

“Having worked in local and national public health for years, I have never experienced such radical non-transparency, nor have I seen such unskilled manipulation of data to achieve a political end rather than the good of the American people,” Daskalakis wrote.

Democratic Sen. Patty Murray of Washington, who serves on the Senate health committee, reacted to Monarez’s ouster by calling for Kennedy to be fired, calling him “a dangerous man who is determined to abuse his authority to act on truly terrifying conspiracy theories and disinformation.”

“If there are any adults left in the White House, it’s well past time they face reality and fire RFK Jr,” Murray said in a statement.

CDC departures follow months of upheaval

The sudden departures come at a tumultuous time for the public health agency. Staff are still reeling from an early August shooting outside the CDC’s Atlanta headquarters by a gunman who police said was upset about COVID-19 vaccines.

Kennedy — a longtime vaccine skeptic — also fired every member of an independent CDC panel tasked with making vaccine recommendations. During Kennedy’s tenure, HHS has made other moves on vaccines that have troubled public health and infectious disease experts. Kennedy halted contracts for mRNA vaccine research earlier this month, and the Food and Drug Administration on Wednesday approved updated COVID-19 vaccines for seniors and people with health conditions, but not for healthy adults and children.  

Meanwhile, the CDC faced hundreds of layoffs this year.

There has been some friction between Monarez and Kennedy over COVID-19 vaccines and the CDC’s vaccine advisory panel, CDC officials told CBS News. Monarez has publicly said that vaccines “save lives.” The Trump administration was also unhappy with the way she had talked about the Atlanta shooting and stopped her from publishing an op-ed about the incident, the officials said.

Mr. Trump nominated Monarez to lead the CDC in late March, calling her a “dedicated public servant” who could repair what he called a loss of public confidence in the CDC “due to political bias and disastrous mismanagement.” Monarez was confirmed by the Senate in a party-line vote in late July, after previously serving as the agency’s acting head starting in January.

She was nominated to lead the agency after Mr. Trump pulled his initial pick for the job, former Florida Rep. Dave Weldon, a physician who was controversial in part due to his past skepticism of vaccines. In private meetings with Weldon, some Republican senators and their staffers grew concerned that he seemed unfamiliar with the CDC’s operations, CBS News reported at the time.

Monarez holds a Ph.D. in microbiology and immunology, though unlike most prior CDC directors, she is not a medical doctor. She previously served as deputy director of the Advanced Research Projects Agency for Health, a federal agency that backs advanced medical research. She also worked in the Obama-era White House’s science and technology office and the Department of Homeland Security during Mr. Trump’s first term. 

During her Senate confirmation hearing, Monarez faced a number of questions about vaccine recommendations. Kennedy has pushed a discredited theory linking routine childhood shots to autism, but during her hearing, Monarez refuted that view and said she has “not seen a causal link between vaccines and autism.” 

“Vaccines absolutely save lives, and if I’m confirmed as CDC director, I commit to making sure we continue to prioritize vaccine availability,” Monarez told lawmakers.

Supernovae are among the most energetic phenomena in the Universe, and definitely one of the most spectacular! These events take place when a star has reached the end of its life cycle and undergoes gravitational collapse at its center, exploding and shedding its outer layers in the process. For astronomers, supernovae are not only a fascinating field of study, shedding light on the evolution of stars, but are also a means of measuring distance and the rate at which the Universe is expanding. They are an essential part of the Cosmic Distance Ladder because their brightness makes them very reliable “standard candles.”

Spotting supernovae represented a major challenge, though, since they are transient events that are extremely difficult to predict. Luckily, astronomers are getting better at spotting supernovae thanks to high-cadence surveys by observatories that continuously monitor the skies. According to a new study led by the Institute of Space Sciences (ICE-CSIC) in Barcelona, it is still crucial to develop protocols and methods for detecting them promptly. They further present a methodology for obtaining the spectra of supernovae as soon as possible by combining wide-field sky surveys with immediate follow-up by telescopes.

The research was led by Lluís Galbany, a staff researcher at the Institute of Space Sciences (ICE-CSIC) and a member of the Institut d’Estudis Espacials de Catalunya(IEEC). He and his colleagues at the ICE-SCIC and IEEC were joined by researchers from the European Southern Observatory (ESO), the Institut de Física d’Altes Energies (IFAE), the Instituto de Ciencias Exactas y Naturales (ICEN), the Instituto de Astrofísica de La Plata (IALP), and numerous universities worldwide. Their paper, “Rapid follow-up observations of infant supernovae with the Gran Telescopio Canarias,” has been published in the Journal of Cosmology and Astroparticle Physics (JCAP).

Artistic elaboration based on images from the original paper Galbany et al., JCAP, 2025. Credit: Galbany et al., JCAP, 2025

Detecting a supernova during the first hours and days after it explodes is essential since the explosion preserves direct clues about the progenitor system. This information helps distinguish between competing explosion models and allows astronomers to estimate critical parameters and study the local environment. This has proved very challenging in the past because most supernovae were detected days or weeks after the explosion event. These explosions fall into two broad categories, which are determined by the mass of the progenitor star.

The first are known as thermonuclear supernovae, which involve stars whose initial mass did not exceed eight Solar masses (typically white dwarfs). If these stars are part of a binary system, their powerful gravity will likely siphon material from their companion, raising the star’s internal pressure until it explodes in a Type Ia supernova. The second type is core-collapse supernovae, which involve massive stars whose initial mass exceeds this limit. As Galbany summarized in an ICE-CSIC press release:

They shine thanks to nuclear fusion in their cores, but once the star has burned through progressively heavier atoms—right up to the point where further fusion no longer yields energy—the core collapses. At that point, the star collapses because gravity is no longer counterbalanced; the rapid contraction raises the internal pressure dramatically and triggers the explosion. The sooner we see them, the better.

As noted, high-cadence surveys that cover large sections of the sky and revisit them frequently are changing this, though protocols are still needed to exploit the data they collect. The protocol developed by Galbany and his colleagues begins with a rapid search for candidates based on the criteria that it was absent in the previous night’s images, and the new light source lies within a galaxy. When both conditions are met, the team triggers the Optical System for Imaging and low-Intermediate-Resolution Integrated Spectroscopy (OSIRIS) instrument on the Gran Telescopio de Canarias (GTC) to obtain spectra from the explosions. Said Galbany:

The supernova’s spectrum tells us, for instance, whether the star contained hydrogen—meaning we are looking at a core-collapse supernova. Knowing about the supernova in its very earliest moments also lets us seek other kinds of data on the same object, such as photometry from the Zwicky Transient Facility (ZTF) and the Asteroid Terrestrial-impact Last Alert System (ATLAS) that we used in the study. Those light-curves show how brightness rises in the initial phase; if we see small bumps, it may mean another star in a binary system was swallowed by the explosion.

The ICE Gran Telescopio Canarias telescope, located at the El Roque de los Muchachos Observatory on the island of La Palma, Spain. Credit: Instituto de Astrofísica de Canarias

The team tested this method using GTC data and found ten supernovae that occurred within six days, two within the first 48 hours. The ten events were divided equally into the thermonuclear and core-collapse categories, and the team confirmed them by making additional cross-matches with data obtained by other observatories on the same patch of sky. Based on the success of their study, the team believes that even faster detections are within reach. As Galbany summarized:

What we have just published is a pilot study. We now know that a rapid-response spectroscopic program, well coordinated with deep photometric surveys, can realistically collect spectra within a day of the explosion, paving the way for systematic studies of the very earliest phases in forthcoming large surveys such as the La Silla Southern Supernova Survey (LS4) and the Legacy Survey of Space and Time (LSST), both in Chile.

Further Reading: ICE-CSIC, arXiv