Canada has lost its measles elimination status...a sad milestone. Now is the time to double down on lowering barriers to routine childhood immunizations and ensuring Canadians have access to credible, science-based information. Link: tinyurl.com/c8nfxvk3

Influenza cases are climbing in Canada. Flu shots are widely available, and can help lower the chance of infection and hospitalization. Below are this year’s flu trends (arrow) vs. the past three years.

Antimicrobial resistance kills over a million people yearly. I joined colleagues before the House of Commons Committee on Science & Research to discuss how Canada can help fight this threat. Local action matters but global coordination is essential. 🇨🇦 ➡️ tinyurl.com/3sfdvzt2

@paulsaxmd.bsky.social knocks it out of the park with his analysis on 2 new COVID vaccine studies. If you want data, nuance & common sense, have a read. Key takeaway: COVID vaccine makes sense for those at greatest risk for severe infection (eg. elderly). Link: tinyurl.com/yc63e9c2

Attending the Global Conference on Biological Threat Reduction in Geneva with colleagues from around the world to strengthen strategies against infectious disease outbreaks, whether natural, accidental, or deliberate. Great to see Canada taking a leadership role in this sphere.🇨🇦

The southern hemisphere offers an imperfect but useful preview of our flu season, and they had a tough one: High case numbers & lower vaccine uptake among those most at risk. Flu shots in Ontario for high risk folks are available now & to the general public starting next week.

A locally acquired case of Chikungunya virus in New York State? This is a first. Chikungunya is a mosquito-transmitted infection that can cause impressive (and sometimes lasting) joint pain and inflammation. Link: tinyurl.com/57ue229x

New 🇨🇦 data in @cmaj.ca (from BC) showing relatively strong population-level measles immunity. Outbreaks are likely to be more focal in under-vaccinated groups. Some age cohorts are still <90% immune, so maintaining high vaccine coverage remains key. Link: tinyurl.com/4tz5eftj

Our team is developing portable digital microscopes that harness AI to automatically detect parasitic infections. This shows great potential to help public health programs expand access to affordable disease screening in low-resource settings. Link: tinyurl.com/4bazch67

Glad to see this finally coming to an end…

“The Ebola virus disease (EVD) outbreak in the Democratic Republic of the Congo (DRC) shows signs of containment, with no new confirmed or probable cases reported since our last update” Some cautious good news from @who.int #IDSky hq_who_departmentofcommunications.cmail19.com/t/d-l-ggllll...

So tragic: Alberta baby born with congenital #measles (mother contracted measles late in pregnancy) died shortly after birth. The province, which has had a massive measles outbreak this year, says this is the 7th case of congenital measles in 2025. www.cbc.ca/news/canada/...

To our American friends who may now be struggling to find health information on US websites: Please check out the Public Health Agency of Canada's website for helpful resources, updated dashboards & practical health tips. 🇨🇦🇨🇦🇨🇦 canada.ca/en/public-he...

Although the genetic fingerprint has shifted a bit, there is absolutely nothing new from a clinical, diagnostic, therapeutic, or preventive perspective. Are we really going to do this every time the virus mutates, which it will continue to do frequently & indefinitely? Link: tinyurl.com/3kt32bm9

Report of the 2024 #marburg outbreak in #rwanda. The response successfully treated two patients in the icu, simultaneously ran vaccine and treatment trials and effectively contained the outbreak. 15/66 cases died. They gave the world a lesson in outbreak response. www.nejm.org/doi/full/10....

🆕 Introducing FirstCallID 🎓 Practical ID teaching for busy clinicians 🚨 Ep 1 is live: How to Do an ID Consult ✔️ What to ask ✔️ What to notice ✔️ What your attending actually cares about 📺 Direct link to video: youtu.be/W1mrYwpxLK0 📘 Follow for updates: @firstcallid.bsky.social #idsky #medsky

Ontario needs a vaccination registry: Kieran Moore https://www.thestar.com/politics/provincial/ontario-needs-a-vaccination-registry-to-identify-coverage-gaps-top-doctor-says/article_9ce14bd7-d362-42ea-9b07-94f37827c133.html More news → CanadaHealthwatch.ca 🍁

A Policy to Override Policy. Every leader & administrator in Healthcare/Public Health (clinical, research, education) should be required to watch this 10 min clip. This creates systems to improve patient care, research & education. By @BradSpellberg tinyurl.com/yc5chesw

More tick-borne illnesses showing up in Canada: a case of Rocky Mountain Spotted Fever (RMSF) likely acquired at Emma Lake, SK. RMSF has also been found in dogs in southern ON & in a person in QC who may have caught it in ON. tinyurl.com/ybuefba2 by Alex Kozroski.

COVID cases are beginning to rise in Canada. While rates remain lower than at this time in recent years, they are still trending upward. Health Canada has also just approved a new COVID vaccine for the fall rollout, targeting LP.8.1 (a sublineage of Omicron). 🇨🇦

It looks like a case of Rocky Mountain Spotted Fever (RMSF) was identified in Quebec. This was recently also seen in dogs in Long Point, ON. RMSF is an uncommon but very serious tick-borne infection. Doxycycline is the treatment of choice.

This summer’s COVID test positivity rate (blue) is lower than the same time in the past two summers (red, yellow).

A quick note: My name and image are being used without permission in social media ads promoting products I do not endorse. I am working with social media platforms and the Canadian Anti-Fraud Centre to have these ads removed. I hope you’re all having a relaxing summer. Cheers,

“Raw milk has been promoted by online wellness influencers and raw food advocates, boosting sales in recent years, but public health officials say it can be risky.” www.cbsnews.com/news/florida...

Canada’s first human West Nile case of the year was just reported in Toronto. Most have no symptoms, some get a fever, and rarely it manifests as a serious neurological illness. Time for the bug spray. Link: tinyurl.com/yjf23nd6 by Nicole Ireland

'tis the season. First identification of West Nile Virus in Toronto mosquitoes this year. www.cbc.ca/news/canada/...

Ontario is now seeing a sharp drop in measles cases, with the trend beginning in early May.

Rocky Mountain Spotted Fever (RMSF) has been reported in dogs in Long Point, Ontario. RMSF is transmitted through tick bites, so humans are also at risk. This infection can be severe. Take care to protect yourself & your pets from ticks. Info from 🇨🇦 @PHAC_GC: tinyurl.com/yc2ev4h2

👧🏽 Since 2008, vaccination against human papillomavirus #HPV is free for girls in Denmark 🔎 Researchers looked at 16,955 cervical cell samples from 8,659 women over a 7-year study period 📉 #vaccination has effectively reduced infections with cancerogenic HPV 16/18 types #IDSky #MedSky #STISky 🧪🩺

A person in northern Arizona has died from a case of bubonic plague, local health officials say.

Canada has recorded the highest number of measles cases since achieving measles elimination status in 1998.

Thirty thousand years of germs: here’s my story about a chronicle of plagues and pestilence recorded in fossil DNA. Gift link: nyti.ms/4ln43UH

Measles cases in Ontario are on the decline (since May).

Happy Canada Day 🇨🇦 🇨🇦 🇨🇦

An independent group of experts has reviewed all available evidence on SARS-CoV-2's origins, including lab leak & natural spillover. Uncertainty remains. Only a methodical & rigorous approach (not partisanship or premature certainty) will lead us to credible answers. Link: tinyurl.com/5v796ent

To our American friends seeking data-driven and independent vaccine advice, please check out Canada’s National Advisory Committee on Immunization (NACI): Evidence-based insights & expert guidance.. 🇨🇦🇨🇦🇨🇦 Link: tinyurl.com/3ejd4b73

Sad news from Ontario: "It is with deep sadness that I confirm that an infant, born prematurely and infected with measles, has tragically passed away in southwestern Ontario." -Dr. Kieren Moore, CMOH tinyurl.com/mckw73bu

An important commentary from Isaac and my colleagues at PHAC. As worried as I am about the situation in the US, I am at least assured that Canada is proactively addressing this threat. Gratitude for the evidence-driven preparedness efforts led by both PHAC and CFIA.

🇨🇦 Canada has secured 500,000 doses of an updated H5N1 (avian influenza) vaccine. Here's a Canadian perspective in @CMAJ on what this means, with colleagues from the Public Health Agency of Canada. Link: www.cmaj.ca/content/197/...

Forgotten but not gone: COVID rates in Canada have been low & declining for several months. However, the Omicron subvariant NB.1.1.8 has been more prevalent in SE Asia & it's likely we'll see more of that here in the near future. (Red = 2022-23; Yellow = 2023-24; Blue = 2024-25)

Our new study in @lancetmicrobe.bsky.social on the population-level impact of novel drugs against schistosomiasis, including drugs with activity against the juvenile form of the parasite. We hope the study can support novel drug development and selection to reduce the burden of schistosomiasis!

1/ Good news...PEP-in-Pocket ("PIP") joins the CDC's HIV prevention toolkit. "Health care professionals might consider a 'PEP-in-pocket' (PiP) strategy for certain patients with infrequent, repeated HIV exposures who decline to use PrEP." www.cdc.gov/mmwr/volumes...

The measles outbreak in Ontario continues to grumble along, with 1,646 cases reported in 2025. To date, the outbreak has occurred primarily (though not exclusively) among unvaccinated individuals in under-vaccinated communities in southwestern Ontario.

The vast majority of people infected in the Ontario measles outbreak are unvaccinated.

Mpox is surging in Sierra Leone. Fortunately a vaccine program is now starting to roll out for those at risk. Link: tinyurl.com/mtw9bwef, by Jody Ray.

🧵1/N New study published in @jama.com on re-emergence of vaccine-eliminated infectious diseases under declining vaccination in the US. We model long-term risk and conditions for return to endemicity for measles, rubella, polio, & diphtheria. Collab w/ @Mathewkiang.com jamanetwork.com/journals/jam...

More than 5 million “zero-dose” children – children who have not received a single dose of an essential routine vaccine – in the African region have been vaccinated since 2024 through the “Big Catch-Up” initiative" www.afro.who.int/news/vaccina...

"Nirmatrelvir–ritonavir (Paxlovid) administered for 15 days did not significantly improve health outcomes in participants with long COVID compared with placebo–ritonavir at day 28." Results of a randomized, blinded, placebo controlled Phase 2 trial: tinyurl.com/stfsjerk

Measles cases in Ontario have passed 900 so far in 2025, far exceeding the annual totals recorded over the past decade. The measles vaccine is highly effective at preventing infection, widely available at no cost, and backed by decades of safety data.