Do you live in Philly? Has your cat been acting crazy? Well, it is likely this craziness is not due to H5N1 infection--but rather the fact that your cat is a cat. In this new preprint with @lhmoncla.bsky.social we find low H5N1 seroprevalence rates in Philly cats. www.biorxiv.org/content/10.6...

Karolinska Institutet KI is inviting applications for 21 Assistant Professor positions in medicine and health @ki.se ki.se/en/about-ki/...

Publishing papers and receiving grants are important...but seeing your PhD student receive a 'thesis of the year' award at graduation is priceless! Congrats Grace! @cambupenn.bsky.social @ceirrnetwork.bsky.social

Jordan's paper showing that immune history affects levels of cross-reactive H5N1 NA antibodies was just posted at Nature Communications. Congrats to Jordan and the team! See thread below when we originally posted on medRxiv... www.nature.com/articles/s41...

New results published in the New England Journal of Medicine finds Moderna’s mRNA flu vaccine gave more protection against illness than the standard flu shot in a Phase 3 clinical trial.

The #hantavirus outbreak on the cruise ship off the coast of Africa is a serious public health event that needs to be handled properly. But if you are having #Covid flashbacks, put those worries to rest. The risk here is to people on the ship & their close contacts. www.statnews.com/2026/05/07/h...

Swiss authorities have confirmed a case of #hantavirus identified in a passenger from the MV Hondius cruise ship. He had responded to an email from the ship’s operator informing the passengers of the health event, and presented himself to a hospital in Zurich, Switzerland, and is receiving care. 1️⃣

This is not good. Most likely not human to human transmission but need to keep close eye on this. www.nbcnews.com/health/healt...

WHO is aware of and supporting a public health event involving a cruise vessel sailing in the Atlantic Ocean.

Check out our new study published today showing that HA head-reactive B cells primed by H3N2 infections in the 1990s can be recalled by contemporary pH1N1 viruses. A huge Penn-CEIRR effort, led by Grace Li from my lab. Congrats to Grace and team! www.cell.com/cell-host-mi...

We are recruiting 1-2 postdoctoral fellows to investigate the specificity of human anti-influenza virus antibodies, and to determine how these antibodies impact global antigenic drift of influenza viruses. Join our lab at Penn in Philly. Reach out if you are interested in applying! Please repost!

Get your popcorn ready!

H5N1 in dairy cows largely has disappeared from the news--a reflection of steeply declining detections. But it continues to circulate on dairies, and researchers continue to debate critical questions about how the virus moves between farms and within herds. www.science.org/content/arti...

Holy cow! Our new study showing that H5 mRNA-LNP vaccines are safe and effective in lactating dairy cows is now posted on @biorxivpreprint.bsky.social! We found that our vaccine elicits protective responses in 2,000 pound dairy cows! 1/ www.biorxiv.org/content/10.6...

Happy to see the peer-reviewed version of this manuscript published yesterday in NEJM-Evidence. @nejm.org evidence.nejm.org/doi/full/10....

Stanley Plotkin had a major hand in the development of a number of vaccines in use today; he designed the rubella vaccine. He remembers the world before widespread use of vaccines & knows what's coming as vaccine policy is rewritten & vaccine confidence is eroded. www.statnews.com/2026/03/02/s...

Our preprint examining the specificity of human antibodies that cross-react with subclade K H3N2 viruses was posted this morning on medRxiv. These studies have implications on what vaccine strains should be selected for next year’s influenza season. 1/ www.medrxiv.org/content/10.6...

We have posted data providing real-time measurement of human neutralizing antibody landscape to seasonal influenza. Data explain spread of subclades K (H3N2) & D.3.1.1 (H1N1), identify subclade K subvariants w reduced neutralization, & can inform choice of strains for next vaccine.

A very few times in my career, I've done an interview that stunned me so much that I've gotten off the phone and walked into furniture. This was one of them. I'm grateful to this mom for her courage and vulnerability in doing this interview. www.cnn.com/2026/01/16/h...

“This isn’t perfect, but if you can decrease your chance of getting flu this year by fourfold, man, that’s a vaccine that I want.” www.cnn.com/2026/01/07/h...

“Although it’s not a complete match with what’s circulating, this vaccine appears to have the capacity to produce antibodies that will likely provide protection.” www.nbcnews.com/health/healt...

We find that subclade K viruses are antigenically advanced; however, this year's flu vaccine surprisingly elicited antibodies in many individuals that efficiently recognized these viruses. The implications are clear: go get this year’s vaccine if you haven’t already! www.medrxiv.org/content/10.6...

Nice in-depth story on immune memory by @amandabkeener.bsky.social in @nature.com. “If we can develop multivalent vaccines that have many different flu antigens in them, we can replace original antigenic sin with a blessing of induced immunity.” www.nature.com/articles/d41...

“There may be less of a vaccine mismatch than many people initially believed.” More on this very soon from our group...Go get your vaccine if you haven't already! www.nytimes.com/2025/12/17/w...

I am excited to share that our work, in which we have dissected the signals driven by the nucleoside-modified mRNA and LNP components of mRNA vaccines that regulate germinal center (GC) responses, is now published in Cell! www.cell.com/cell/fulltex...

A picture is worth a 1000 words. The birth dose of hepatitis B vaccines in the USA eliminated perinatally acquired hepatitis B infection from over 20,000 cases a year before the vaccine was introduced to <20 cases a year. The gaslighting by the current members ACIP is obscene, unethical and cruel.

BREAKING: Man from Washington state dies after being infected with H5N5 bird flu

“If there’s ever a year to get a flu vaccine, this is the year.” Even in years with vaccine mismatches, the flu vaccine consistently prevents severe disease and hospitalizations. Now is the time to get a flu shot if you haven't already, because we will likely have a lot of flu activity this year.

CDC FluView is back, and our fears look like reality. 50.8% of circulating H3N2 viruses belong to the 2a.3a.1-K subclade, which have 2 mutations in a very important antigenic site. Our own 2025-2026 vaccine immunogenicity data will be posted in the next couple of weeks. www.cdc.gov/fluview/surv...

Our lab's paper describing the North American H5N1 epizootic is out now in Nature! So thrilled to have this out, and congratulations to @lambod50.bsky.social for all the fantastic work on this: www.nature.com/articles/s41...

CDC FluView hasn't been updated in a month, so I will start posting Philadelphia flu activity updates weekly. It is especially important to track flu in the US this year, since there are reports of a severe early flu season in parts of Asia. The PA department of health also has a nice website. 1/2

After a quiet summer, the bird flu virus H5N1 is hitting poultry flocks hard in the run-up to the holidays — and in the midst of a federal government shutdown. w/ @emilyanthes.bsky.social (Gift article) www.nytimes.com/2025/10/22/h...

Reports of severe flu cases in Hong Kong. If I was a politician, I would strengthen international collaborations to study infectious diseases in other countries. Now is a good time to get a seasonal flu vaccine in the US…there are signs we could have an early season. www.info.gov.hk/gia/general/...

Our lab's first paper is out! Led by Jordan Ort, we developed NextClade datasets that enable rapid H5 clade assignment via NextClade. We deployed these during the start of the H5 cattle outbreak, and we finally published the paper in Virus Evolution academic.oup.com/ve/article/1...

I'm proud of our new study showing that some people born in the 1990s have high levels of antibodies that cross-react to H3 viruses from the 1990s and....contemporary H1N1 viruses. Such a surprising story led by Grace Li, in collaboration with many Penn-CEIRR labs. 1/ www.medrxiv.org/content/10.1...

Pennsylvania has now joined with our other northeastern states to create the Northeast Public Health Collaborative to protect public health, provide vaccine recommendations and share expertise.   Protecting public health only works when we’re united.

In June, an ACIP member said that 250 pediatric flu deaths were no big deal. Maybe today we will find out that a handful of hepatitis B related cancers, transplants, and deaths are also not a big deal to them either. Welcome to the new public health. We are aligned to a manifesto, not science.

In new study led by @ckikawa.bsky.social, we provide near real-time data on human neutralizing antibody landscape to influenza by measuring ~26,000 titers to >100 recent viral strains Data can inform vaccine selection & evolutionary/epidemiological modeling www.biorxiv.org/content/10.1...

A few months ago, when asked if his Nobel prize changed his science, David Baltimore said "I got into science because I love data. And the only thing I really care about in my life is data. And for that reason I didn't stop doing science because I won an award." www.youtube.com/watch?v=XqUK...

A new study led by @cambupenn.bsky.social Jordan Ort in my lab was posted on medRxiv. We found that humans infected with H1N1 viruses in childhood have high levels of Abs that cross-react to the NA of H5N1 viruses...decades after their childhood H1N1 infections. 1/ www.medrxiv.org/content/10.1...

Looks like one of our ‘imprinting’ papers was cited in the HHS data package, despite our conclusion that people receiving an ancestral mRNA vaccine were better at producing antibodies against variants compared to unvaccinated people.

“Dr. Bhattacharya might not realize that many human vaccines are based on live attenuated viruses, where we similarly cannot definitively quantify antigen amounts produced in recipients. The mRNA and live attenuated vaccine platforms have both proven to be safe and effective in clinical studies.”

Science and health shouldn’t be wrapped up into politics. This leaves the US woefully unprepared for the next pandemic.

The former NIH director on the catastrophe unfolding for American research. youtu.be/lW9c6t4potU

Dissolving ACIP is an absolute mistake. We need accurate information—not fringe theories—guiding government recommendations on which vaccines to give which people.

Canada's National Advisory Committee on Immunization (NACI) is now the definitive source for evidence-based vaccine recommendations in North America. www.canada.ca/en/public-he...

Unbelievable. Truly unbelievable.

Happy to be part of @kingofpathogens.bsky.social study showing mRNAs encoding IL-12 enhance CD8 T cell responses to co-administered HA mRNA vaccines. Study led by Emily Aunins and Anthony Phan from the Hunter lab @upenn.edu www.science.org/doi/10.1126/...

Anyone that has been around a lab knows that the trainees really drive the research, while most professors just sort of guide the ship. Most innovation comes from our trainees. Old professors like me will be able to survive these cuts, but our young scientists and our future will be destroyed.