Yonatan Grad

I think they’re all worth considering, and of course it’s likely multifactorial and even changing as new interventions are introduced—hence this piece! Shifting behaviors? Bexsero? Doxy-PEP?

People have their favorite explanations, but it's not clear--and without a better understanding of what's driving these trends, we won't be able to optimally inform public health interventions. We lay out the possibilities and how to address them for gonorrhea. (2/2) dash.harvard.edu/entities/pub...

New STI surveillance data from the CDC shows declines in gonorrhea, chlamydia, and primary and secondary syphilis (though tragically congenital syphilis continues to increase). What explains these declines? (1/2)

Delighted to see our paper studying the evolution of plasmids over the last 100 years, now out! Years of work by Adrian Cazares, also Nick Thomson @sangerinstitute.bsky.social - this version much improved over the preprint. Final version should be open access, apols.
Thread 1/n

Defining and Estimating Outcomes Directly Averted by a Vaccination Program when Rollout Occurs Over Time During the COVID-19 pandemic, estimating the total deaths averted by vaccination has been of great public health interest. Instead of estimating total deaths averted by vaccination among both vaccinat...

New preprint reporting a large piece of work by Katherine Jia to define estimands and estimators for direct impact of vaccines with arbitrary rollout schedules arxiv.org/abs/2509.05508
with Alyssa Bilinski, @chrisboyer.bsky.social and me

Racing against antibiotic resistance  — Harvard Gazette Scientists fear funding cuts will slow momentum in their war with evolving bacteria— one of America’s most urgent healthcare problems.

“I think of antibiotics as infrastructure” @yhgrad.bsky.social interviewed for the Harvard Gazette, 'Racing against antibiotic resistance'. Read it here at bit.ly/47PdOqv

A group of volunteers wearing hair nets and aprons below the caption, "IID at your (community) service!" Names of volunteers from left to right: Abigail Frey, Maia Mesyngier, Eric Neubauer Vickers, Qinqin Yu.

IID truly lived up to the name of the nonprofit they volunteered with—Community Servings! QinQin Yu, a postdoc in the Grad lab, organized a department volunteer outing at Community Servings, which provides medically tailored meals to families facing chronic illness and nutrition insecurity.

#stihiv2025 🧪
Historians make clinicians /scientists think very differently about what we mean by #SexualHealth and disease.

Anna Hanley U Birmingham

UK 19thC laws continued to have a long hold on attitudes and treatment of women with #STIs

Paternalism patriarchy misogyny blame

Interesting to think about implications for assessment of trends in incidence / prevalence estimates with NAAT overcalling active infections.

We are on the lookout for postdocs for two different projects at the intersection of ecology, evolution, and the human microbiome.

See thread for more information and reach out!

Opinion | This system is critical to Americans’ health. We must defend it. Medical progress depends on independent journals to advance science without political interference.

Please to write this @washingtonpost.com Op-Ed with Eric Rubin about the importance of independent medical journals like ours @nejm.org & @jama.com

wapo.st/4kUqfV9

This is a great 🧵 and a great team.

Always getting ahead of the curve on thinking about #gonorrhoea #AntimicobialResistance and new drugs #zoliflodacin #gepotidacin

Looking forward to hearing more in Montreal
@stihiv2025.org

Very interesting preprint!

Modeling introduction of 2 new drugs for #gonorrhea, the authors found that equal allocation (introducing at the same time) was better than sequential (introducing after resistance to prior agent) for #AMR

Counter to what we normally assume in #ABstewardship.
#STIsky

Study hints doxyPEP use coincides with rise in tetracycline-resistant gonorrhea in US

A genomic analysis finds the percentage of US gonorrhea isolates carrying tetracycline resistance genes rose from 10% in 2020 to more than 30% in 2024.

www.cidrap.umn.edu/a...

We're hiring a modelling postdoc at PSI Oxford for two exciting projects: 1) modelling the early immune responses to Nipah vaccination, and 2) joining the PRESTO team working on immunobridging in vaccine evaluation studies.

tinyurl.com/5abbxrjh

Get in touch for more info! Deadline 4th August.

Use of antibiotic to reduce STIs appears to be fueling some antibiotic resistance, research shows The use of the antibiotic doxycycline to reduce STIs appears to be fueling some antibiotic resistance, according to new research.

And a great discussion by @helenbranswell.bsky.social here: www.statnews.com/2025/07/09/d...

Now out in NEJM. Kudos to @dhelekal.bsky.social and @tatumdmortimer.bsky.social : www.nejm.org/doi/10.1056/...

Use of antibiotic to reduce STIs appears to be fueling some antibiotic resistance, research shows The use of the antibiotic doxycycline to reduce STIs appears to be fueling some antibiotic resistance, according to new research.

Using doxycycline after unprotected sex — doxy PEP — is effective at reducing some sexually transmitted infections in some people. But new research suggests is probably also driving development of resistance to tetracycline antibiotics in some bacteria. www.statnews.com/2025/07/09/d...

Excited to share our paper on viral load dynamics of West Nile virus in mosquitoes! Key findings:

1. Variation in pooled Ct values from mosquito traps reflect underlying biological and epidemiological mechanisms.
2. WNV prevalence estimates are improved by using Cts rather than +ve/-ve pool status.

📣 We’re recruiting 1-2 Group Leaders! NCMBM is looking for early-career researchers ready to establish their independent research groups!

🧬 With an attractive start-up package, help us shape the future of molecular biosciences and medicine in 🇳🇴 and be part of the @nordicembl.bsky.social!

Comparing Strategies to Introduce Two New Antibiotics for Gonorrhea: A Modeling Study Introduction Drug resistance in Neisseria gonorrhoeae is an urgent public health threat. The anticipated approval of two new antimicrobials for gonorrhea prompts the need for evidence-based rollout st...

⚠️ New preprint ⚠️: Two new antibiotics are likely coming for gonorrhea 💊. How should we deploy them in the US to minimize drug resistance? @kroster.bsky.social @dhelekal.bsky.social Eva Rumpler @yhgrad.bsky.social [1/10]
www.medrxiv.org/content/10.1...

A thread about ongoing erasing and ignoring science... 🧵

ECR Data Visualisation Workshop Please complete this application to attend the Data Viz workshop. This event will be held at the 2025 STI & HIV World Congress in Montreal, Canada on Wednesday, July 30th from 11:30-13:30. Effective...

If you are an early career research attending @stihiv2025.org and interested in learning more about data visualization in R, @odileharrison.bsky.social , Sim Dabee, and I are organizing a workshop during the conference (11:30am-1:30pm on Wednesday). Register here: forms.gle/e4UL1NG62PUD...

A fun conversation with Carl this afternoon about his excellent book AIR-BORNE--the recording is available at the HSPH youtube site: www.youtube.com/user/Harvard...

RFK Jr. moves on vaccines could have broad ramifications for public health, says expert | Harvard T.H. Chan School of Public Health Yonatan Grad, professor of immunology and infectious diseases, comments on the potential impact of recent decisions related to vaccines made by Health and Human Services Secretary Robert F. Kennedy Jr...

Dr. Yonatan Grad @yhgrad.bsky.social, Professor of immunology and infectious diseases comments on the potential impact of recent decisions related to vaccines made by Health and Human Services Secretary (HHS) Robert F. Kennedy Jr. Read it here at bit.ly/3T2KPqX

Sang Woo (Daniel) Park and I are excited to share a new preprint, "Susceptible host dynamics explain pathogen resilience to perturbations" [1/8]

www.biorxiv.org/content/10.1...

Here Is All the Science at Risk in Trump’s Clash With Harvard (Gift Article) More than 900 research grants worth $2.6 billion are in jeopardy. So is the 80-year-old model of American science.

"The money the government sends to Harvard is not a subsidy to advance the university's mission. It's a payment for the role Harvard plays in advancing the research mission of the U.S."

"This is larger than any individual grant. What we are losing is a future."

www.nytimes.com/interactive/...

What it’s really like … to know I’m going to miss my Harvard graduation because of Trump’s travel ban Like many other international students I have had my educational dreams suspended without reason – and learned plenty about racism and resilience

Deeply affecting article by an @hsph.harvard.edu PhD student denied the opportunity to graduate due to blanket exclusion of Sierra Leone citizens by the US Government. A very particular example of pointless cruelty by the US Government. www.theguardian.com/global-devel...

Wellcome Connecting Science hybrid conference Antimicrobial Resistance – Genomes, Big Data and Emerging Technologies Conference dates: 23–25 March 2026 Location: Hinxton Hall Conference Centre, Wellcome Genome Campus, UK and online Bursary deadline: 01 December 2025 Abstract deadline: 15 December 2025 Registration deadlines: In person: 24 February 2026 | Virtual: 17 March 2026

Explore the important role of #genomics and data-driven technologies for accelerating advances in #AMRresearch, at our Antimicrobial Resistance meeting! #AMR2026

Discover the latest developments informing a dynamic global response to controlling this crisis.

🗓️ 23–25 March 2026

📎 bit.ly/3SWzJUm

Application deadline extended to July 4th - don't miss the opportunity, well worth it