An atomic bomb explosion (U.S. Air Force/AP) 
 
 The Centers for Disease Control and Prevention has rescheduled a teaching session on the public health response to a nuclear blast that was to take place Tuesday. 
 
 The session was to feature presentations from U.S. experts on public health preparedness and response and radiation, including one titled “Preparing for the Unthinkable.” It was planned months ago as part of a regular series of monthly webinars the CDC called Public Health Grand Rounds, officials said. 
 
 But media interest in the topic was unusually strong, given the escalating tensions between President Trump and North Korean leader Kim Jong Un and their most recent war of words over which leader has the larger nuclear arsenal and bigger “nuclear button.” About three dozen media outlets had expressed interest in attending the session, which is broadcast from CDC’s headquarters in Atlanta. The initial CDC announcement featured a photograph of the distinctive mushroom cloud from a nuclear blast. 
 
 On Friday afternoon, the agency said it was changing the topic to influenza and took down the mushroom cloud photo and the announcement about public health responses to a nuclear blast. 
 
 “With the spike in flu cases around the country, this Grand Rounds will provide key and timely information for public health professionals on how to reduce the spread of seasonal flu in communities and adjust to spot shortages in antiviral drugs because of high influenza activity in some areas,” the CDC said. “The previous public health topic will be rescheduled for a future Grand Rounds.” 
 
 Public Health Grand Rounds are held to give the most up-to-date, scientifically accurate information to clinicians, researchers and others working in public health. 
 
 CDC’s initial announcement about the originally planned topic had described the session like this: 
 
 “While a nuclear detonation is unlikely, it would have devastating results and there would be limited time to take critical protection steps,” the CDC website noted. “Despite the fear surrounding such an event, planning and preparation can lessen deaths and illness. For instance, most people don’t realize that sheltering in place for at least 24 hours is crucial to saving lives and reducing exposure to radiation. 
 
 “While federal, state and local agencies will lead the immediate response efforts, public health will play a key role in responding.” 
 
 Read more: 
 
 CDC says flu is now widespread across the county, and it’s not going away anytime soon 
 
 Trump to North Korean leader Kim: My ‘nuclear button’ is ‘much bigger & more powerful’ 
 
 CDC scientists pursue deadly monkeypox virus in Africa ||||| The Centers for Disease Control and Prevention has decided to postpone its session on nuclear attack preparedness next week. Much attention had been drawn to the timing of the agency’s session, which was publicized just days after President Trump touted the size of his nuclear button compared with North Korea’s. 
 
 Late Friday afternoon, the C.D.C. announced that it had changed its mind about next Tuesday’s topic, making a last-minute revision to reflect concerns about cases of severe flu. 
 
 “To date, this influenza season is notable for the sheer volume of flu that most of the United States is seeing at the same time, which can stress health systems,” the agency said. “The vast majority of this activity has been caused by influenza A H3N2, associated with severe illness in young children and people 65 years and older.” 
 
 Kathy Harben, a spokeswoman for the agency, said the Tuesday session would now address guidance for health professionals on trying to reduce the spread of the flu and to help with shortages of antiviral medicines in some hard-hit areas.
– Fear the flu, not the bomb. The Centers for Disease Control and Prevention on Friday announced that a session on nuclear attack preparedness scheduled for Tuesday will be postponed to an unspecified date, with the session's topic switching to flu and what can be done to stem its spread. "To date, this influenza season is notable for the sheer volume of flu that most of the United States is seeing at the same time, which can stress health systems," the CDC explained, per the New York Times. The session was originally to feature officials from all levels of government discussing US preparations for a nuclear blast, with presentations on "Preparing for the Unthinkable" and "Roadmap to Radiation Preparedness." The Times notes that the CDC made no mention of whether the delay was at all influenced by the outsize interest in the session, which was announced shortly after President Trump's tweet about nuclear-button size. The Washington Post reports the sessions are part of a larger monthly webinar series called Public Health Grand Rounds, and notes that roughly three dozen media outlets had shared interest in covering the session at the CDC's Atlanta HQ. (This 21-year-old thought rest could take care of the flu; he died days later.)