Daniel Park
@Daniel_E_Park
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PhD, MSPH. Epidemiologist & Professorial Lecturer at GW. Global health, vaccines, microbiomics, & antibiotic stewardship. Part-time musician & English nerd.
Washington, DC
Joined July 2020
For anyone claiming that the epidemiologists got the pandemic "wrong" - I think in many cases, communicators (whether it be politicians, well-meaning scientists from ancillary fields, etc.) did not fully understand or convey what we were saying. And there was a lot of noise.
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I do quick cognitive tests as part of my daily work routines to adjust my tasks based on my current state. My very "mild" case of COVID resulted in a ~20% slowdown and 10% reduction in overall cognition, which only gradually resolved over a year.
You cannot recognize well the ongoing cognitive impairment because of the ongoing cognitive impairment.
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Nice coverage from Vox on some of the benefits of the Novavax COVID vaccine: similar effectiveness, fewer side effects, and potentially longer lasting protection.
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How our family stayed COVID-negative when my 2-year old was infected. An epidemiologists’ perspective.
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Vaccines likely lower transmission, in addition to reducing infection and severe illness. New study shows Novavax and Moderna significantly reduce viral load (amount of virus) in the upper respiratory tract.
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A trio of Novavax preprints, showing 1) remarkable durability >6 months, 2) cross protection against newer variants, and 3) low reactogenicity (side effects), supporting NVX as an excellent booster platform.
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Finally, the FDA has authorized the Novavax XBB booster, without restrictions. The NVX het. boost option is 1) up to 9x more effective at preventing infections, 2) has fewer side effects, 3) provides durable, broad protection vs new variants.
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Just released: Pretty remarkable 1-year durability data for Novavax 2-dose primary series. Though there is some expected waning, there was >65% efficacy at 1y (mRNA options typically wane to this level by ~4-5 months). Also fewer waning differences by age.
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Novavax reduces viral load by 2.78 log10, while the Moderna vaccine was 2.12. The log10 scale is 10x for each step, indicating Moderna reduces viral load by just over 100x, and Novavax reduces viral load by over 600x. No significant reductions seen for others.
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Important study of Novavax (ancestral & BA.1) and Moderna boosters in primates. All have effective long-term immune responses and lower viral replication, but only NVX had significantly lower viral loads in upper airways, which could limit transmission.
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The updated novavax vaccine shows excellent, broad immune responses against the latest variants, including Eris (EG.5.1) and XBB subvariants in animal models. Barring surprises, the vaccine should be approved within a week and available in 2-3 weeks.
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New RCT study shows the "conventional" Novavax COVID vaccine has a similar side effect profile to the routine meningococcal vaccine, and fewer side effects than the mRNA options. Side effects are a leading cause of COVID vaccine hesitancy. This can help.
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Small but helpful study of Novavax from Germany highlighting some of the key benefits of this vaccine option. Very low incidence of side effects among this high-risk population. And excellent long-term protection (95% at 10 months).
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New study enrolling looking at Novavax in immunosuppressed individuals, building on earlier studies that show the novavax vaccine produces a more robust and durable response in this important population.
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Excellent broad cross neutralization to variants with the upcoming JN.1 Novavax COVID vaccine, including some of the best responses to variants that are likely to be dominant this late fall and early winter.
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Just out: mRNA COVID-19 vax do not establish in long-lived plasma cells; could account for faster waning vs. infection. Other mechanisms still protect durably vs. severe illness, but improving durability is important. Adjuvants (like in Novavax) may help.
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There is a common and dangerous misconception that the JN.1 vaccines are inferior to KP.2 vaccines. In reality, JN.1 and KP.2 vaccines will both provide excellent protection, with each being slightly better in different aspects. But the experts were right to pick JN.1.
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Good news for Novavax and vaccines - novavax has entered into a partnership with Sanofi to co-commercialize their COVID vaccine and to explore a combination flu (Sanofi) COVID (NVX) vaccine.
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Interesting: different immune responses to Novavax & mRNA COVID vaccines. TLDR: NVX has higher proportion of the "best" IgGs (IgG3), while mRNA have higher of the "not always good" IgG4. IMO more importantly, NVX has stronger Fc-effector functions.
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I've recently discussed sudden behavioral issues in school aged children w/ parents and teachers. In most cases, this followed the kids being sick. Reminder: COVID can cause increased anxiety, aggression, and defiance in children.
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I’ve been asked for a list of Novavax studies. Apologies for the long thread but compiling some selected studies into a narrative here, hope this is helpful:.1) Original RCT shows >99% efficacy against severe disease and >90% vs. infection:
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This WaPo article serves as a reminder that having multiple vax platforms is important. mRNA vaccines are great, but newer doesn't necessarily equal better. Cuba achieved broad coverage and strong protection with a protein vaccine (similar tech to Novavax).
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Preprint: Immunity from mRNA vaccines wanes more rapidly due to inability to induce long lived plasma cells in bone marrow. This seems unique to current mRNA, and less for the adenovirus vector (J&J, AZ) and protein-based (Novavax) options.
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Reminder that viral infections (flu, COVID, EB, etc.) are not good for you. They significantly increase risk of neurodegenerative and autoimmune disorders, such as Alzheimer's, dementia, and multiple sclerosis (among many others).
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Another paper from the PICOBOO randomized trial, evaluating second boosters after mRNA priming. 1) novavax is more durable .2) mRNA vaccines have higher antibody responses.3) novavax has fewer side effects.More nuances in this thread .
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Even mild COVID can result in long-term persistence in the body, multi-organ damage (e.g. brain and heart damage), and long COVID. The benefit of these relatively simple protective measures outweigh the inconvenience, especially in high-risk settings.
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Preprint: saponin adjuvants (like the one in Novavax) shown to enhance durability (length) of protection compared with mRNA options. Potentially relevant as we shift to annual doses for COVID-19.
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RCT of Covovax / Novavax COVID vaccine in children 2-11y and 12-17y. Excellent immune responses across variants that had higher titers than adults. Also very low rate of side effects, with no myocarditis reported.
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Finally, I should note that this is just our experience. There is a good deal of stochastic luck in who gets infected and who doesn’t. We were grateful to avoid further transmission and to protect some high-risk. I hope this is helpful to some others as well.
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Lesson 1: If you know local circulation rates, you can adjust your threshold for when mild symptoms may warrant a test. Lesson 2: We can get tests for free from our local library. This is a great resource that should remain widely available.
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Grateful to have gotten the novavax vaccine yesterday. Just a sore arm after 24h, a vast improvement over my prior experiences w/ Pfizer and moderna. A bit surreal after seeing the data on lower reactogenicity and improved efficacy for years but finally experiencing it myself.
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Preprint: comparison of mRNA & protein vaccines and neurodegenerative and neuroinflammatory responses to SARS-CoV-2. Infection causes neurological damage. Both vaccines generally protective, but among higher-risk mice, only the protein-based vaccine was protective.
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Looks like I triggered some folks by mentioning tests, masks, and vaccines in one thread. But to use this as a learning opportunity, much of the difference in views comes down to whether you view COVID as nothing to worry about, or something more harmful.
How our family stayed COVID-negative when my 2-year old was infected. An epidemiologists’ perspective.
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Preprint: Interesting study from Korea comparing homologous NVX (Novavax) and BNT (Pfizer) COVID vax. One of the few places where there are enough NVX doses to do this analysis. Slightly better effectiveness (16% better) with NVX after primary series.
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Lesson 6. Masking, ventilation, and staying up to date on your vaccines provides multi-layered protection against infection. If you are worried about vaccine side effects, the Novavax option is a traditional platform with fewer side effects.
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In a cohort of immunosuppressed individuals who failed to respond to mRNA and viral vector COVID-19 vaccines, two doses of Novavax were able to generate an immune response. Figure: T-3 & T-2 are mRNA/viral vector, T1 & T2 show responses after NVX.
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Nice data brief in JAMA today. Around 7% of US adults have had long COVID. Vaccination strongly associated with decreased likelihood of long COVID.
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More evidence showing the updated JN.1 vaccines are protective against currently dominant strains (KP.3.1.1 and XEC). Just in case you needed extra motivation to stay up to date on your COVID boosters.
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RCT comparing Pfizer, Moderna, and Novavax boosters following AZ priming. All vaccines safe and effective. mRNA have faster and higher antibody responses, but also wane faster. mRNA also slightly more reactogenic.
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Large study provides support for many long COVID (LC) findings:.1 Fatigue & neurological symptoms most common.2 Women more likely to have LC.3 Reinfection has milder acute symptoms but more severe LC.4 Vaccination reduces LC risk.5 ⬆️post-COVID infections.
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Strategy 4: Vaccines. My wife and I received Novavax boosters 4 months prior. Studies suggest effectiveness of NVX boosters last 6+ months. With my heterologous boosting (primary was Moderna and Pfizer boost #1), I was likely in the protective window.
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Lesson 3: Not all rapid tests are created equal. And sometimes those positives are truly faint. When in doubt, try another test. PCR is most sensitive but not as readily available. A positive rapid antigen means you are likely infected and infectious.
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Strategy 1b: Anytime he went to the bathroom (#2), we would turn on the exhaust. We would also close the lid and leave the bathroom immediately after flushing. Toilet flushes aerosolize viral particles.
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Strategy 2: Masks. My wife and I used high filtration masks, particularly during days 2-5 when he was coughing and more readily positive on his rapid antigen text. Both kids would also mask, especially when they were near each other (which we avoided).
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Risk Mitigation Strategy 1a: First thing we did was to open some windows. Improved ventilation is critical in reducing the amount of potentially aerosolized virus. We also had a small HEPA filter I placed outside his bedroom and left running.
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More proof of viral persistence and latent reservoirs with COVID-19. Great study. More bluntly, SARS-CoV-2 can set up a home in your organs and cause long-term damage over months or years. Staying up to date on COVID-19 vaccines may protect against this.
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Lesson 4: Staying up to date with vaccines decreases transmission risk and shortens time to clearance when infected. I was also less worried about his well-being as vaccines reduce risk of long COVID and severe symptoms.
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Most of the COVID vaccines induce robust B cell responses and humoral immunity, but immune responses take 2-3 days to fully kick in. By minimizing the initial exposure, you may provide your body time for a systemic immune response before the virus becomes systemic itself.
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Recently released immunogenicity results from a Phase 3 RCT of the original Novavax vaccine when used as a booster. Good safety profile and excellent immune responses regardless of prior vaccine platform, even against Omicron BA.1 and BA.5.
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Increasing vaccine uptake reduces community circulation. Lower circulation overall helps everyone, from kids to the elderly. Fewer sick days. Improves economic activity. Reduces long COVID. Fewer empty seats at the family dining table.
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In late February, our toddler woke up with a runny nose. Anyone with a toddler will know runny noses are very typical. However, thanks to ongoing local surveillance (which I monitor ~weekly), I knew case rates were slightly elevated in our area, and that led me to test.
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Vaccines likely reduce chances of 1) being infected, 2) developing severe illness if infected, 3) transmitting the virus to others.
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These results are in line with earlier animal models where the Novavax platform was associated with the largest decrease in viral replication in the upper respiratory tract.
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Lesson 5: Increasing air circulation and filtration is critical in enclosed indoor environments, including bathrooms.
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I took primary care duty for my son, whereas my wife spent more time with our daughter. We figured it was better if only one of us got sick, instead of both.
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When ppl tell me COVID is mild, I agree that the mortality rate is lower now, but I note that it causes long term damage to multiple organ systems. Depending on the situation I add that SARS-CoV-2 can set up a reservoir in the testes & cause severe damage.
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His first test came back with a very faint positive line. So faint, in fact, that I gave him another rapid test. Clear negative. Third was also a clear negative. Fourth (by which he was starting to get annoyed with me) finally confirmed the faint positive.
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We were fortunate to catch this fairly early when he was slightly less infectious. Since he had primary COVID vaccination, which accelerates clearance and lowers viral load, I knew we’d have to “lock it down” for ~4-5 days to minimize transmission risk.
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Strategy 3: Although our son loves playing with his sister, we kept them in different rooms for ~5 days with limited interaction in our backyard. My wife and daughter ate meals first (to limit their exposure to aerosolized particles in the dining room) before my son and I ate.
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I give vaccines much credit for staying negative, as during one coughing-induced middle-of-the-night cry session a few days into his infection, I had forgotten my mask in my bedroom and only realized it after holding him for a few minutes.
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In a large study, vaccinated individuals have significantly lower inflammatory immune profiles after COVID when compared with unvaccinated individuals. Benefits of vaccination are not just for severe diseases, but systemic inflammation w/ "mild" infection
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For myself as primary caregiver of a squirmy, coughing toddler, I knew I’d likely be exposed at some point during the infection course. My goal was to have a minimal viral load at first exposure, so as to allow my B cells time to ramp up and generate antibodies.
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I should add that we all tested daily. For my son to track his relative course – as predicted the test lit up around day 3, then quickly subsided and turned negative on day 5-6. We eased up on precautions around then, but maintained open windows and stayed outdoors when possible.
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Preprint: Pfizer preprint supporting that JN.1 and KP.2 vaccines are similarly effective against currently circulating strains, including KP.3.1.1 and XEC. And some very interesting info supporting earlier suggestions about conformation of JN.1, KP.2, and KP.3.1.1
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Anecdotal update from the DC region - some people who recently got novavax were told by the pharmacist they may run out of doses w/in a week due to strong demand. Ironic that after many people waited so long to be eligible, they have such a short window to be able to get a dose.
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Just a reminder that COVID damages the brain, along with other organ systems.
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Protection from infection with bivalent mRNA efficacy waned quickly, to 21% after 2 months in this new study. Considering protection doesn't fully kick in for ~2 weeks, this window of protection is limited .
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Also a quick note from today's ACIP slides that the application under review at FDA would allow Novavax boosters even after mRNA priming/prior boosters. FDA approval is now the last step before Novavax becomes broadly accessible.
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Long-term protection of 95% at 10 months is remarkable. The authors note this may be higher due to non-reporting of asymptomatic or mild infections, but this is in line with prior studies showing durable protection with Novavax.
Just released: Pretty remarkable 1-year durability data for Novavax 2-dose primary series. Though there is some expected waning, there was >65% efficacy at 1y (mRNA options typically wane to this level by ~4-5 months). Also fewer waning differences by age.
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The novavax shot demonstrates excellent efficacy against SARS-CoV-2 variants in adolescents, with low reactogenicity and no observed myocarditis. Great news that should hopefully help uptake in this age group. via @JAMANetworkOpen.
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Additional evidence showing generally lower reactogenicity with Novavax. If you or someone you know has concerns about COVID vaccine side effects, this may be a good option for you. Excellent efficacy as well.
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There have also been studies suggesting the Novavax vaccine may be uniquely effective are reducing upper respiratory tract carriage (and therefore likely to reduce transmission):.
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The pharmacist noted they continue to see exceptionally strong demand for the novavax vaccine. I also see that many members of the FDA's own vaccine advisory committee and many top immunologists around the world are also opting for the novavax. A far cry from last season.
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Heads up: the winter COVID-19 surge has started. Testing is less common now, so wastewater surveillance provides a good system for assessing community circulation. If you haven't gotten your updated COVID-19 booster, now is a great time.
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Large meta-analysis of COVID vaccines: .mRNA and Novavax (and Sputnik & Cuban vaccines) roughly equivalent in terms of protection. mRNA are more reactogenic (higher side effects).
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I just wrote a @theacecoalition letter urging Novavax approval before the government shutdown. Here's my letter. h/t: @skywatcher77 . Write yours here:
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As expected, Novavax displays efficacy against new variants including JN.1. Staying up to date on your vaccines is an important way to protect yourselves and your loved ones as COVID numbers continue to increase this holiday season.
@Novavax tells us that data from mice and nonhuman primates shows. "our vaccine induced cross-neutralization against JN.1". "similar to what has previously been shown for responses against XBB.2.3, XBB.1.16, FL.1.5.1, EG.5.1, and BA.2.86".
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Children are at risk of having COVID dozens of times over their lifetime, which is a serious threat to their health as they reach adulthood.
I've recently discussed sudden behavioral issues in school aged children w/ parents and teachers. In most cases, this followed the kids being sick. Reminder: COVID can cause increased anxiety, aggression, and defiance in children.
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For any EU friends, Novavax has received a positive opinion from the CHMP Opinion in the EU. Once the EU commission provides final approval in the coming days, the Novavax option should become available. NVX has excellent efficacy and fewer side effects.
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I'd encourage everyone to look into updated boosters and discuss w/ your provider. My personal top reasons that I'll be in line are to help prevent: 1) spreading COVID to those around me, 2) long-term sequelae / organ damage w/ even mild infection
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Recently released findings from a major NIH-funded trial support the use of Novavax as a heterologous booster. Good neutralization responses across all variants, albeit slightly lower for XBB (as expected).
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9b) Booster coverage could double if authorization of the NVX is expanded to allow boosting after mRNA. If an additional 12% of the population is boosted, my rough calculations suggest this could prevent at least 53,000 COVID hospitalizations and 13,000 deaths annually in the US.
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I should add for our US audience that heterologous boosting with Novavax also had similar findings of improved durability over at least 8 months. "NVX participants had an 89% reduction in risk of self-reported ‘breakthrough infection’ compared to BNT-30".
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Of note, there is generally a much higher proportion of individuals choosing Novavax from high-risk populations, often due to adverse reactions from prior mRNA doses. Here, there were zero sick-leave days after NVX receipt, and negligible reportable side effects.
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This misconception about JN.1 inferiority may cause many more deaths via hesitancy, since globally, almost all countries will only have JN.1 vaccines. The public health messaging must be that both JN.1 and KP.2 are excellent options. Full stop.
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Epidemiologists did remarkable work in the early days of COVID-19. Within months, they:.- Accurately predicted the timing of every major wave for the next 3 years. - Warned SARS-CoV-2 would likely become endemic. - Identified risk of aerosol transmission.
Of many, let’s pick Marc Lipsitch, one of the most respected epidemiologists globally. By April 2020 (in ~1 month), he published a paper that (given the closest assumptions to capacity & social behaviors) almost exactly predicted each wave from 2020-2022.
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FDA has authorized updated Novavax JN.1 vaccine for ages 12y+. NVX will be joining the mRNA options soon and will be broadly available. As previously noted, all of the updated vaccines provide excellent protection against currently circulating variants.
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Many EU agencies are excited about the updated Novavax vaccine. Germany just confirmed purchase of 10.6 million doses for this fall, 3 million in Italy. Europe has run large RCTs comparing vaccines showing benefits of heterologous boosting with AZ and NVX.
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Further evidence that COVID-19 vaccination protects you from poor cardiovascular outcomes, this time from a cohort of over 20 million people. Vaccinated individuals had at least half the risk of adverse outcomes w/in 30 days post-infection.
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People often ask me what the optimal timing of boosters is. That's an incredibly complex question that varies by individual, including location, anticipated future exposure, family or contacts who are at higher risk, and variants. This paper covers a few of these nuances.
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XBB COVID vaccine uptake is ~30% so far this yr. Negative: this is lower than it should be. Positive: this is already 60% higher than bivalent uptake last yr. Too early to tell numbers, but I'm certain having Novavax available has improved uptake.
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Novavax original vaccine shows good efficacy in large cohort (20,000+) in Italy during Omicron. Note that efficacy should be higher with the NVX XBB version (authorized yesterday) so this is more informative for the platform in general. h/t @EricTopol
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Staying up to date on vaccines and improving air quality can have population level benefits, and protect our ability to "think" both individually and collectively.
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Fyi a review of many of the advantages of heterologous boosting, with a focus on the Novavax vaccine. Potential advantages include better immune responses and durability, lower reactogenicity, and likely improved uptake .
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I closed my Public Health lecture today with this quick thought. We can't control everything around us, but we can control our actions, we can impact those around us, and we can save and help millions around the world with our work, which is now more important than ever.
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Important study in Nature may have some implications for reactogenicity and/or efficacy of mRNA vaccines. The pseudouridine can cause a frameshift (e.g. mistranslation) when the body converts mRNA to proteins.
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Comparison of NVX (Novavax) and BNT (Pfizer) after primary or booster from South Korea through 180 days. NVX primary series offered slight "added protection" against infection (~10%) and severe disease (~35%), while homologous boost findings were mixed.
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I should note that Pfizer was not evaluated in the study being discussed, but it could have a similar reduction to moderna based on prior studies.
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Recent studies demonstrate that in addition to structural brain changes, many effects may be immune meditated .
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