Marc Lipsitch

Marc Lipsitch

@mlipsitch.bsky.social

Professor of Epidemiology Harvard Chan SPH, Director, @ccdd-hsph.bsky.social. Views my own.

1.8K followers461 following70 posts

Key points: A popular "hazard difference" estimator for averted outcomes is biased, but an unbiased one can be calculated from status-based aggregated data (knowing y/n vaccinated for those with and without the outcome). For avertible outcomes, this doesn't work; need to know dates of vaccination.

Marc Lipsitch reposted

For Marburg, a reservoir is known, but serious efforts at countermeasures have been spurred by human outbreaks. We conclude that virus prospecting is neither necessary, sufficient, nor particularly feasible as a driver for medical countermeasure (at least vaccine) development.

There may be other justifications for the expense and risk incurred by such prospecting efforts, but vaccine development is not a strong one. Pathogen identification at the human interface (in spillover cases) and efforts to avoid or remediate human drivers of spillover risk may be more efficient.

Then we identify the large number of targets for which vaccines are arguably more urgent than for any virus known only in non-human hosts: the 26 families of viruses known to infect humans. Among these, there are no vaccines approved for even a single member of 10 of the 26 families.

Last, we take a look at detailed timelines of human and animal isolation of filoviruses (ebolavirus spp. and Marburg) and note that in ebolaviruses, animal reservoirs have not been confirmed but countermeasure development has followed large human outbreaks.

First we note that historically, finding a novel virus in animals before the first known human outbreak did not in any case spur countermeasure development. Poignant examples are Zika (1947 in animals, 1952 in humans, vaccines only much later) and monkeypox (1958-1970, vaccine R&D only recently).

Then we note that most major virus outbreaks of the 21st century have been caused by viruses first discovered in humans. Next, we show that recent priority pathogen lists for countermeasure development have contained known human pathogens but shown little relationship to virus discovery in wildlife.

In it we asked if prospecting for novel viruses in wildlife is justified, as often asserted, as a means to speeding the development of countermeasures against emerging infections. We find little evidence that it is.

Marc Lipsitch reposted

Republicans, before you vote to close 1 of 4 nursing homes, can you update us on where those people will go? Maybe call a few seniors in your state and go over plans for where they go next? Or call the son whose dad has dementia and tell him how he can be a full-time caregiver?

Elizabeth Warren@warren.senate.gov

BREAKING: 1 in 4 nursing homes say they will be forced to close if Republicans pass Trump’s Big Beautiful Bill. No grandma should be kicked out of her nursing home so that Mark Zuckerberg can buy another Hawaiian island.

Marc Lipsitch reposted

Marc Lipsitch reposted

Marc Lipsitch reposted

The goal is plainly and literally to cut the number of people involved in basic science in the US by 70%

Dan Garisto@dangaristo.bsky.social

From over 300k to less than 100k. A picture of smaller, reduced science.

The Department of Health and Human Services has a process for making and updating recommendations like this, using expert scientists and clinicians. RFK is deliberately putting Americans' health at risk and sidestepping good science for political reasons.

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US health agencies like CDC and NIH and FDA remain full of dedicated and exceptional scientists and health professionals doing the right thing for public health. But this example shows they can be overruled by an exceptionally unqualified secretary of HHS.

The Department of Health and Human Services has a process for making and updating recommendations like this, using expert scientists and clinicians. RFK is deliberately putting Americans' health at risk and sidestepping good science for political reasons.

As the quality of health advice becomes more politicized and arbitrary, and less science-based Americans are going to have to turn to state health officials (some of them) or other countries for good advice.

Marc Lipsitch reposted

Replying to @surtlab.bsky.social

I'm a current Harvard graduate student and I found out today that I had my NSF GRFP terminated without notification. I was awarded this individual research fellowship before even choosing Harvard as my graduate school

Please consider a comment today if you are in the US. See the advice (shared from an email I received) in the follow-up posts below this one. Tomorrow is the deadline. This is an important part of scientific freedom in this country.

Marc Lipsitch@mlipsitch.bsky.social

Time Sensitive: Public comment on Schedule F (removing civil service protections for many federal employees INCLUDING THOSE WITH AUTHORITY OVER GRANTS) ends tomorrow. Notice is here: www.govinfo.gov/content/pkg/... . Comment here (green button) www.federalregister.gov/documents/20... .

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If thousands of scientists say that political interference with grants assessment is going to destroy the scientific integrity of federal grants, the agency will have to explain why the rule doesn’t do that (which it can’t because this is precisely why the new regulation is being instituted).

By law, the proposing agency (in this case, the office of personnel management headed by Project 2025 coordinator Russell Vought) must take comments into account and respond to them, thereby forming a record that can be challenged in subsequent litigation.

An easily overlooked consequence of research funding cancellations: completed research these days requires hundreds to several thousand dollars to be published due to publication fees from journals. Without support for these fees many pieces of scientific work will be near invisible.

A partial solution is to post preprints of everything (so far still free). But the junior scientists who lead much of this work need peer-reviewed publications (and sadly the name of the journal still matters way too much in evaluations) so this solves only part of the problem.

Marc Lipsitch reposted

🎓 The GOP’s reconciliation bill is a direct hit on higher ed: – $351B in cuts education & workforce programs – eliminating subsidized student loans – Taxes on scholarships & endowments – & more. ACE calls it a “full-out assault” on access to college. Read below ⬇️ www.acenet.edu/News-Room/Pa...

acenet.eduHouse Reconciliation Bill Targets Higher Education with Deep Cuts and Tax HikesA budget reconciliation bill advancing in the House of Representatives proposes hundreds of billions of dollars in cuts to student aid, imposes new taxes on colleges and universities, and jeopardizes ...
Stand Up for Science!@standupforscience.net

🚨 They just advanced the Republicans’ reconciliation bill through the Budget Committee. This bill guts healthcare, scientific breakthroughs, and a livable future to fund tax cuts for billionaires. We need pressure NOW. More on this to come - stay tuned. www.npr.org/2025/05/19/n...

Marc Lipsitch reposted

Given that there are 435 voting members of Congress, I would have hoped for more than 25% of House members to support American innovation in science and technology. 112? That’s it? No one else wants answers?!?!

Congressman Bill Foster@repbillfoster.bsky.social

NEWS: I just led 112 of my colleagues in demanding answers from the Trump Administration on their funding freeze of the National Science Foundation. Cutting off NSF funding threatens vital research, stalls innovation, and risks ceding global scientific leadership to China.

Marc Lipsitch reposted

Looking for examples of beautiful, controversial or impactful microbial modelling papers - ideally a mixture of the above! It’s for teaching in the context of microbial eco/evo/epi. The modelling should be relatively easy to understand for a master’s student with a biology background.

Marc Lipsitch reposted

Breaking: Over 150 college presidents across the country just signed a letter condemning the Trump administration’s threats to dictate their policies. “We speak with one voice against the unprecedented government overreach now endangering American higher education.”

New Brief Report out in @pnas.org with Katherine Budeski: www.pnas.org/doi/10.1073/... Focusing a virus risk ranking tool on prediction -- highlighting the importance of training models for viral emergence only on data available before emergence has happened.

pnas.orgFocusing a viral risk ranking tool on prediction | PNASPreparing to rapidly respond to emerging infectious diseases is critical. SpillOver: Viral Risk Ranking is an open-source tool developed to assess ...