March 2024 – Pediatric Infection Connection

Chocolate Bunnies

Bud WiedermannMarch 31, 2024March 31, 2024Leave a comment

It's Easter time, when my thoughts turn to chocolate bunnies. Not only do they taste better than real bunnies (well, to think of it, I may have never tested a real bunny), but I have been unable to find any reports of tularemia transmitted from chocolate bunnies.

Although we are clearly beyond the peak of winter respiratory infection season, we still have plenty to think about from last week.

Covid Household Transmission From Asymptomatic Children

A prospective study showed a high secondary attack rate (SAR) for covid in households likely stemming from asymptomatically infected children. The study was well designed to try to answer this question, identifying asymptomatic children in Canada and the US who were tested for SARS-CoV-2 for either non-household contact with a known covid case or as part of routine hospital screening. The study covered a 15-month period, and results were analyzed according to viral variants predominating in the community at those times: 1/31/21 - 6/30/21 was predominantly alpha or mixed variants, 7/121 - 12/19/21 was delta, and 12/21/21 - 4/22/22 was omicron. The authors compared household SAR of SARS-CoV-2 positive children to rates of those who tested negative. There are many nuances to the study, but here's the bottom line:

SARs were higher with younger index cases (< 5yo versus 13 - <18 yo), if the index case eventually developed covid symptoms (versus continuing asymptomatic), and during delta and omicron time periods versus the interval when alpha/other variants predominated. If you have access to the full text of the article, skim the Methods section to get an idea of the tremendous amount of effort involved in collecting this kind of data.

Dengue in Puerto Rico

This past week Puerto Rico health authorities declared a public health emergency due to dengue, the first time this has happened in the territory since 2012. What I'm sure is alarming to those authorities, beyond the sheer number of cases (524) in 2024 so far, is that this isn't peak dengue season. As befitting the mosquito vector, cases tend to rise in the summer when it is wetter. See below, with my apologies for lack of English translation. You can click on the Week 10 report in the PR DOH Arboviral Diseases Weekly Report for the full document.

In other words, the worst may be yet to come. (The dashed red line is the epidemic threshold which is higher in summer/early fall weeks; August usually is the peak month for rain in Puerto Rico.) We can certainly expect cases in the mainland US, including in non-travelers living in Florida and other states that have experienced autochthonous dengue cases in the past.

Meningococcal Group Y Alert

CDC issued another HAN report about increasing cases of invasive meningococcal disease due to group Y, a phenomenon that has been noticed for a couple years now.

Note that the incidence rate is very low; this represents a relatively small number of cases but still quite significant given the severity of meningococcal disease. Now is a good time for frontline healthcare providers to read up about meningococcal disease in general including indications for vaccination and identification of high risk groups, especially for this outbreak: age 30-60 years, Black or African-American descent, and living with HIV; as well as the usual risk factors of close contact with a case, people at the age extremes, certain immunodeficiency diseases such as complement deficiencies, and some college settings. The HAN notice includes many useful links.

How's Your Ventilation?

CDC issued revised guidelines for indoor ventilation to help prevent respiratory virus transmission, including SARS-CoV-2. Take a look and maybe ask your friendly office landlord how your building stacks up.

Apparently I've missed it for a couple years, but CDC also has an interactive tool to see how changes in ventilation may improve viral particle clearance. I disappeared down that rabbit hole playing with it for about half an hour. Note the disclaimer at the top of the web page about some information needing updates, though I think it mostly concerns the old 6-feet social distancing and other recommendations rather than the tool itself. Here are results from a home with intermittent HVAC operation, uncertain filter rating, and running the HVAC system for 1 hour after a 4-hour period of gathering. Better results can be achieved with continuous HVAC operation (i.e. keep it on continuously during times of high occupancy), high MERV-rated (Minimal Efficiency Reporting Value) filter, use of HEPA (High Efficiency Particulate Air) cleaner, and other factors.

However, before you overhaul your home system or threaten your office landlord, note what this is really saying. The outcomes pertain to effectiveness of particle reduction in the air, which is different from measuring whether it lessens transmission of SARS-CoV-2, influenza, RSV, or other viruses. It makes sense that there would be some correlation, but until someone does a more definitive study comparing systems and actual viral infection rates, we don't really know to what degree ventilation efficiency changes infectious disease outcomes. Compare this with the study of secondary household transmission mentioned at the top today's post - a more difficult study design with results more directly related to clinical outcomes than just a study of airborne particles in a laboratory chamber. And, parenthetically, the household transmission study did not include individual home ventilation as a factor, so even those results are incomplete. This is complicated!

Measles Update

Measles marches on in the US and across the world. US cases continue to grow, now at 97 since January 1, fed in large part recently by outbreaks in Chicago: 21 new cases in the past week just in Chicago alone. Here are the latest US numbers and distribution from CDC:

In Search of Easter Candy

Once again my wife and I have used our granddaughter as an excuse to buy Easter candy. She's a picky eater, now the only chocolate bunny she will touch must be dark chocolate without any added flavorings or other adulterations. I applaud her good taste, but perhaps next year I'll do this shopping more than a few days prior to Easter Sunday. I had no trouble finding a multitude of milk chocolate bunnies, some with various additives including peanut butter, salted and unsalted caramel, marshmallow, and other ingredients that I might have considered inedible if presented separately from chocolate. Plain dark chocolate bunnies apparently are almost extinct, definitely at least a critically endangered species.

I should have kept track of my steps and car odometer for this year's chocolate bunny safari, though I doubt even the thousands of steps I tallied will offset my Easter candy ingestion.

Obstinacy or Ignorance or Fear

Bud WiedermannMarch 24, 2024March 24, 2024Leave a comment

Those words written by a famous children's author in 1988 remain relevant today; details to follow after a few mentions of other pediatric infectious disease news from the past week.

Covid Serology Update

The Infectious Disease Society of American updated their guidelines for use of covid serology testing. It is the 4th update since the pandemic began, but there isn't much new here. Currently over 95% of the US population has evidence of immunity either from natural infection, vaccination, or both. Serologic testing of individuals mostly is discouraged because it won't provide any useful clinical information to manage an individual's situation. About the only use might be to check immunity in immunocompromised individuals to help decide if immunotherapy could be warranted for prophylaxis or for treatment of active infection.

Covid in Young Infants

Early in the pandemic, most very young infants diagnosed with SARS-CoV-2 infection were hospitalized. This was due to a combination of the usual practice for febrile infants less than 1 month of age as well as the uncertainty of infection outcomes in this age group. I recall from my clinical experiences that it appeared that most young infants actually did well, though there were exceptions. Finally we have a study that gives us some more detailed data about young infants early in the pandemic. It is a secondary analysis of a prospective global study that recruited children presenting to pediatric emergency departments with illness and tested for covid. The study design allows for much more detail (and presumably more validity) than the other designs such as review of administrative data. The study (actually 2 studies combined) enrolled between March 2020 and February 2022. They ended up with 432 children testing positive for covid to compare with 616 testing negative. Clinical outcomes were generally more severe in the SARS-CoV-2-negative infants:

So, at least early in the pandemic, young infants with SARS-CoV-2 infection fared pretty well.

A Colorful Variant Update

Nothing new about this, but I admit to a strange attraction to colorful covid variant charts. I thought it was interesting to look back to see how the JN.1 variant progressed in the US.

The JN.1 shade of purple has been called "indigo purple" (hex #660999).

Varicella Misdiagnosis

A new CDC report suggests clinicians aren't too skilled in diagnosing varicella infections, perhaps because it is now much less common due to effective vaccination. The Minnesota Department of Health looked at suspected varicella cases from 2016 to 2023, a time when they implemented a new system for processing PCR testing of lesions. Of 208 suspected varicella cases, only 45% had positive tests; in vaccinated patients, the number dropped to 22%. They attributed this to unreliability of clinical diagnosis of varicella, especially in vaccinated patients, but I suspect other factors (improper specimen collection technique, testing unlikely varicella patients "just to be sure") may be contributory as well. Anecdotally I've certainly noticed how difficult the diagnosis varicella-zoster virus infection can be for younger clinicians who don't have the experience of seeing multiple cases in the pre-vaccine era.

Speaking of Misdiagnosis ...

I'm in my broken record mode again here. In case you've been hibernating or torporing, we're in the midst of a global measles surge. I read with alarm of a measles vaccine shortage in Canada. There are no signs of a similar shortage in the US; you can always check on US vaccine shortages at this CDC site. With spring break upon us now, and summer travels coming up, all of us need to brush up on measles diagnosis. Thankfully we have a lot of help.

Last Sunday, the CDC issued a Health Alert Network post with a number of useful links. The American Academy of Pediatrics provides a one-pager with great advice as well as a 5-minute video. Another source I've found very useful for years is from a now out-of-print textbook, Krugman's Infectious Diseases of Children. When I discovered libraries no longer carried it, I tracked down a used copy of the 10th edition (1998) released by a university library and have made continued good use of their black and white diagrams. Here's the clinical progression of illness, the key highlight here is the prodrome of a few days before the rash appears. This is very helpful in suspecting a measles diagnosis because the prolonged prodrome is very unusual in pediatric infectious exanthems.

Also useful is the development and distribution of the rash:

I failed to find a current global measles map so return to the CDC website to at least give a current view of US measles cases. For this calendar year we are now up to 64 cases spread over 17 jurisdictions.

Many clinicians may not remember that, though the first measles vaccine was approved for use in the US in 1961, it wasn't until 30 years later that a second dose was recommended. That was spurred by cases in the late 1980s appearing in vaccinated school children, the first major sign that a single dose wasn't sufficient to prevent outbreaks. That second dose was first recommended for 11-12 year olds by the AAP, subsequently dropped to the 4-6 year age group in 1997 to come into agreement with the CDC. Importantly, the interval between the 2 doses can be as short as 28 days for MMR and 90 days for MMRV vaccines, and early vaccination down to 6 months of age is indicated in special circumstances, such as for children who will be traveling internationally. Frontline pediatric providers need to be proactive in alerting parents planning international travel to ensure that their children ages 6 months and older are protected. Scroll down to the Special Situations section on the CDC immunization schedule notes.

Roald Dahl

I learned just recently that this famed children's book author lost a daughter to measles in 1962. He wrote 25 years later, "Olivia, my eldest daughter, caught measles when she was seven years old. As the illness took its usual course I can remember reading to her often in bed and not feeling particularly alarmed about it. Then one morning, when she was well on the road to recovery, I was sitting on her bed showing her how to fashion little animals out of coloured pipe-cleaners, and when it came to her turn to make one herself, I noticed that her fingers and her mind were not working together and she couldn’t do anything. 'Are you feeling all right?' I asked her. 'I feel all sleepy,' she said. In an hour, she was unconscious. In twelve hours she was dead.”

She had developed measles encephalitis. He wrote this in the late 1980s to encourage parents in the United Kingdom to accept a new MMR vaccine for their children (monovalent measles vaccine had been introduced in 1968 in the UK). He also wrote, “In my opinion parents who now refuse to have their children immunised are putting the lives of those children at risk. In America, where measles immunisation is compulsory, measles, like smallpox, has been virtually wiped out. Here in Britain, because so many parents refuse, either out of obstinacy or ignorance or fear, to allow their children to be immunised, we still have a hundred thousand cases of measles every year.”

Much has been written about Dahl's dark side (e.g. "an equal-opportunity bigot"), but I give him credit for trying to help children and their parents avoid the misfortune he and his family experienced.

Spring is … Springing

Bud WiedermannMarch 17, 2024March 18, 2024Leave a comment

I actually had to pull out the lawnmower this week, to cut some weedy grass running amok in the yard. Nonetheless, I'm buoyed by the approach of the vernal equinox next Tuesday, the official start of spring. Winter will be done, and with it the winter respiratory viruses. They will reliably be replaced with spring respiratory viruses.

Here's a look at the pediatric infectious disease news the past week.

Details on the Failed GSK RSV Vaccine Trial

We've known for about a year that GlaxoSmithKline's RSV vaccine trial in pregnant people was stopped due to safety concerns: a higher rate of preterm births in the vaccine group compared to placebo. Now we have more details, similar to what was reported to FDA and shared in various meetings. Preterm birth rate was 6.8% (237 of 3494 infants) in the vaccine group and 4.9% (86/1739) in the placebo group; it was statistically significant. Neonatal mortality was higher in the vaccine group, 0.4% versus 0.2%, but did not reach statistical significance.

On the other hand, vaccine effectiveness was pretty good:

The currently approved maternal RSV vaccine from Pfizer also had a hint of a safety signal for preterm birth, less so than the GSK product, and these signals combined resulted in the Pfizer vaccine being approved for a later time in gestation, at 32 weeks at the earliest. Postmarketing surveillance is ongoing. Perhaps the most difficult part of assessing this safety signal is whether it is real or not. We are lacking a key factor in making this assessment: biologic plausibility, i.e. the mechanism by which these vaccines might cause preterm birth. Without that, it is still possible this represents just a chance observation. From my perspective, I would still encourage RSV vaccination for pregnant people as well as nirsevimab therapy for at risk infants born to unvaccinated mothers. We have time for more discussions of any new data prior to our next RSV season this fall.

Waterborne Disease Outbreaks Associated With Drinking Water

I'm a big fan of CDC's Surveillance summaries, and this one published last week is of interest. The report concerns 214 outbreaks from 2015-2020. I wasn't thrilled to see my home state represented prominently.

Outbreaks occurred year-round, and biofilm exposures predominated.

In case you aren't familiar with biofilm-associated outbreaks, here's the quick explanation from the text:

"...microbial communities that attach to moist surfaces (e.g., water pipes) and provide protection and nutrients for many different types of pathogens, including Legionella and NTM [non-tuberculous mycobacteria]... Biofilm can grow when water becomes stagnant or disinfectant residuals are depleted, resulting in pathogen growth... Furthermore, biofilm pathogens are difficult to control because of their resistance to water treatment processes (e.g., disinfection)... Exposure to biofilm pathogens can occur through contact with, ingestion of, or aerosol inhalation of contaminated water from different fixtures (e.g., showerheads) and devices (e.g., humidifiers)..."

Not to minimize the severity of these events, but I couldn't help thinking about a whole new version of Hitchcock's Psycho shower scene based on this.

Legionella was by far the most common pathogen. The report has detail on every outbreak by year and location, as well as a listing of contributing factors. It's a great roadmap for future prevention.

Measles (Again)

It seems like I could devote every week's post entirely to measles and not run out of things to say. Here's the current US situation.

As I've stated previously, it's the sheer number of unconnected sites that concerns me now. Let's put this into some perspective.

As of March 14, we have 58 cases reported from 17 jurisdictions. In all of 2023, we had the same number, 58, reported from 20 jurisdictions in the US. So, we're way ahead of the game for recent years, but we're also not breaking any records compared to pre-pandemic times.

Looking more closely at the 2 biggest years recently, the 2014 (and somewhat 2015) numbers had a large contribution from a single site, Disneyland. More impressively, the 1274 measles cases in 2019, the highest number in the US since 1992, largely involved orthodox Jewish communities in New York - relatively epidemiologically isolated communities with very low immunization rates. A CDC update in fall 2019 (I couldn't find a final tally) stated that 75% of cases for the entire country that year originated from these communities.

Fingers crossed that we don't eclipse the 2019 figures this year, but with reduced vaccination rates and already widespread measles transmission occurring, it doesn't look good. We're just now coming to the spring break and summer travel season - importation of measles from travelers has been a large contributor to US measles outbreaks in the past.

Pediatric Covid ICU Admissions

A recent report of registry data from 55 hospitals during the first almost 2 years of the pandemic showed that about 8% children <21 years of age admitted to intensive care with covid had immunocompromising conditions (ICC). Secondary bacterial infection was more common (9.5% versus 7.3%) and mortality (11.4% versus 4.6%) was higher in the ICC group.

That Pesky Flu

The map is getting a little greener, apropos of springtime. Note in the link you can animate the map to show progression from the fall to the current week.

Better seen here, we did experience a little pause in our decrease of ILI, now headed down but at 3.7% still above the official "epidemic is over" mark of 2.9% for this year.

Any Chipmunk Sightings?

My 2024 Farmer's Almanac says that the real harbinger of spring in the eastern US is the appearance of the eastern chipmunk (Tamias striatus) above ground. As opposed to their squirrel brethren, chipmunks at my house don't bother my bird feeder, so I'm OK with them. I learned that although they stay below ground for the winter, they aren't true hibernators but rather experience torpor. They may sleep for several days in their bedrooms, followed by a trip to the underground pantry for snacks. Sounds like a good plan for retirement.

Are You an Owl or a Lark?

Bud WiedermannMarch 10, 2024March 10, 2024Leave a comment

Another round of Daylight Saving Time. I came across a new article suggesting that potential harms of DST depend on your individual chronotype, or, more simply, whether you are an owl or a lark. I definitely fall into the lark category. More on this later, but let's dive into what's been happening in pediatric infectious diseases the past week.

New IDSA Laboratory Test Guidelines

Just out is an updated guideline from the Infectious Diseases Society of America. It might be my favorite guideline of all time, but at 244 pages I recognize it's not for everyone. Let me mention a couple items that I notice some frontline healthcare providers may not know about but are important to avoid misleading test results (a garbage-in-garbage-out scenario).

First concerns the use of swabs, starting on page 8 of the pdf guideline document. Always use a swab for sampling throats, conjunctiva, superficial wounds (aerobic culture only), some nose, nasopharynx, and vaginal testing, and sometimes in special circumstances related to institutional- or manufacturer-related instructions for the product. Never use a swab for surgical tissue - submit the tissue itself making sure it doesn't dry out before processing. The same applies for "respiratory fluids and secretions, endophthalmitis and keratitis, nasal sinus, otitis media, biopsy, abscess fluid, fungal and acid-fast bacilli specimens, formed stool, epiglottitis, diarrheal illness, and when anaerobes are suspected opt for tissue or fluid in anaerobic transport... Never submit a swab for analysis that has been dipped into a fluid or exudate. Send an adequate volume of the fluid or exudate instead." There's also an in-between situation where larger volume sampling isn't feasible, such as with an open wound (at least obtain a needle aspirate of leading edge).

The second pertains to urine specimens, the bane of my existence when consulting on possible UTI based on specimens that have sat around for considerable time before processing, such as placed in a lab collection box in an outpatient setting. Some key points, starting on page 119: "Urine collected for culture should not be kept at room temperature for more than 30 minutes. Hold at refrigerator temperatures or utilize a preservative tube if not processed by the laboratory within 30 minutes." The authors also mention the perils of relying on urinalysis because techniques have not been standardized and often require subjective interpretation. Especially if you are dealing with a child with possible UTI, obtain a good mid-stream voided or catheterized urine specimen and, again, don't let it sit at room temperature too long before analysis.

Different considerations arise when sampling urine for sexually transmitted infection - here, the first portion of urine voided is best for detecting pathogens by nucleic antigen amplification testing.

Speaking of Throat Swabs

The biggest problem in diagnosis of streptococcal pharyngitis is performing throat testing in children highly unlikely to have streptococcal pharyngitis. In this setting, a positive result is much more likely to represent a clinically-irrelevant carrier state and result in unnecessary antibiotic exposure for the child. Some heavy hitters in the group A streptococcal world published a review on this recently, but unfortunately it is not available without subscription to the journal. The authors describe differences in GAS testing between the US and Europe, compare and contrast rapid antigen detection and NAAT testing, and again mention situations where testing should not be performed: children less than 3 years of age unless known exposure, children with signs of viral infection including cough, runny nose, or hoarseness, and absence of "bona fide" clinical suspicion for strep throat if you use a clinical scoring system such as Centor or McIsaac.

Nirsevimab Worked Liked We Hoped

Nirsevimab effectiveness was 90% in preventing hospitalization for RSV infection in infants during their first RSV season, according to CDC data on 699 hospitalized infants. This is actually at the upper end of the confidence interval from prior clinical trials.

AI for Otitis Media

I seem to be on a track of personal banes of my existence as a consultant; misdiagnosis of acute OM is near the top. Although I don't see any of us being replaced by artificial intelligence anytime soon, a new report has some glimmer of hope that it might help us with AOM. It uses a not-yet-available iPhone app with an otoscope; you can use voice to control when to take a photo. Watch the video (at the link to the article, not in the screenshot below) to get an idea of what's involved. It's not nearly ready for prime time, but stay tuned.

Is Covid a Risk for Development of Autoimmune Rheumatologic Inflammatory Disorders?

This study of millions of adult patients from Korea and Japan utilizing a claims database would suggest that it is, with adjusted hazard ratios around 1.25 - 1.3. So far this is just an association and does not determine causality. Also, genetic risks for autoimmune disorders differ in Asian versus US populations (think Kawasaki Disease), so the results may not be broadly applicable.

Influenza is Still With Us

I've officially retired my WRIS (Winter Respiratory Infection Season) section. Really we're only waiting for flu to wind down, though we still have too many covid hospitalizations and deaths. Here's the most recent Fluview map, looking a little more encouraging:

In the meantime, the FDA VRBPAC met on March 5 to officially recommend trivalent vaccines for next fall. The disappearance of the B/Yamagata lineage means we won't need a quadrivalent vaccine as in past years. Next up is CDC/ACIP recommendation in June.

Medical Injustices in the Past

It was painful for me to read, but I highly recommend the NEJM series highlighting medical injustices and biases perpetuated in its publications. The current article is about eugenics. Apparently there were a few voices trying to speak up against these practices in the early part of the 20th century, but they were drowned out by the majority, many of them physicians. You don't need a subscription to the journal for this series.

My Inner Lark

On a lighter note, I was delighted to learn that I might not be at such high risk for adverse events of Daylight Saving Time. A recent study looked at the effects of the DST change on sleep and work productivity in 155 full-time workers in Germany utilizing survey methodology. The effects varied with individual chronotype; that is, the "owls" are those that tend to stay up and wake up later than "larks," the early to bed and early to rise group. There's actually a tool to determine chronotype! The study found that us larks are less affected by the shift to DST.

Lots of evidence exists that the DST shift is associated with harmful effects, from medical illness to car crashes to work productivity. However, this is an extremely messy phenomenon. We have good evidence that the shifts are associated with poor circadian rhythms, a biologic plausibility for harmful outcomes, but only an epidemiologic association with these bad outcomes. With too many factors that can't be controlled or accounted for, probably the only way we will know if DST is bad is if the bad outcomes lessen when we quit using DST. I recall 2 prior instances where an epidemiologic association was likely confirmed to be causal: the association of aspirin use with Reye Syndrome in children, and the association of infant sleeping position with Sudden Infant Death Syndrome. The aspirin industry fought against the concept, but Reye Syndrome essentially disappeared when aspirin use for symptom relief in young children ended. SIDS rates plummeted with the Back-to-Sleep programs.

I don't recall ever seeing a lark, but apparently a subspecies of horned lark inhabits Maryland. I guess I'll need to rise early to spy one.

From CornellLab All About Birds.

I’m Optimistic

Bud WiedermannMarch 3, 2024March 3, 2024Leave a comment

It was a busy week for infectious diseases, not in the sense of more outbreaks but rather more epidemiologic and vaccine data that point to better health for the future.

The big topic of the week was the Advisory Council on Immunization Practices regular February 2-day meeting. In retrospect, pediatric healthcare providers won't have any major new recommendations to work with; those are likely coming following the next meeting the end of June. I wasn't able to view as much of the meeting as I had hoped, patient care interfered a bit, but I did review all the presentations for those that I missed hearing live. Let's dive in.

ACIP

The Council discussed 9 different topics, but only 3 involved voting: COVID-19 vaccines (vote in favor of a spring vaccine for some high-risk people), Chikungunya vaccine (vote for use in some US adult travelers and in laboratory workers), Td vaccine availability for those with contraindications to receiving pertussis vaccine (discussion followed by a vote regarding the Vaccines for Children progam), influenza vaccines, polio vaccines, RSV vaccines for adults, meningococcal vaccines, pneumococcal vaccines, and the new Vaxelis combined product for diphtheria, tetanus, pertussis, polio, Hib, and hepatitis B. I'll expand on just a few of these topics. (Note all of the graphs/figures below are from the ACIP web site presentation slide link for the February meeting.)

RSV

We saw the most up-to-date representation of RSV epidemiology, showing that the epidemic curve for this year looks a lot like prepandemic years (see last presentation in RSV session).

A good part of the discussion centered on risk of Guillain-Barre syndrome following vaccine, compared to risks of GBS in the baseline population. Both are rare events, but I think at this point it is reasonable to conclude that GBS is a rare risk of RSV vaccination, though not enough to outweigh benefits for high risk populations.

A quick look at the benefits versus GBS risks for adults > 60 years of age (Melgar presentation from RSV session):

Note risks might vary with vaccine type - hard to know with rare events and large confidence intervals, plus both in the ballpark of background GBS numbers.

Influenza

This session was interesting for me to see a preliminary assessment of vaccine effectiveness for the 2023-2024 flu season. I'll just show you an overview of VE in the pediatric population; note that multiple methodologies are used to measure VE. (See slides from Frutos presentation in the influenza section.)

This is good VE for flu, certainly the CDC and WHO were on track for choosing the best combination of strains for this season. Look for the vote for next season's vaccine composition in June.

Meningococcal Vaccines

The focus of the discussion was how best to incorporate meningococcal B vaccine now that we have an approved combination vaccine containing this serogroup. Here are the main options discussed, from the 1st Schillie presentation:

The issues are complex, primarily due to 3 factors. First, meningococcal group B infections are extremely rare; traditional cost-effectiveness models show that meningococcal B vaccination in the US is by far the most expensive vaccine; very few cases are prevented due to the rarity of infection. Second, vaccination at age 11-12 risks significant waning of immunity by the age for peak meningococcal disease in adolescents; it might make sense to move the first dose to a later age. (The main argument against this is the confusion caused by eliminating the long-standing practice for vaccination at age 11-12, perhaps lowering overall vaccine acceptance.) Third, it is clear that not all meningococcal disease risk in adolescents is equal: college attendance is prime, but there are other behavioral risk factors (1st Schillie presentation):

The discussion was mainly to hear input from all stakeholders and then go back to the drawing board. Expect a vote on this at the June meeting - it will greatly impact your summer vaccine guidance for adolescents and young adults.

COVID Vacines

This section of the meetings seemed to garner the most publicity. Of course most of the results presented dealt with adults, given the relatively lower risk for bad outcomes in children plus low rates of vaccinations. Most helpful I thought were the discussions about covid VE in recent months looking at the fall monovalent vaccine.

These are great numbers. Also mentioned was the fact that waning of efficacy hasn't been seen yet, but that could just be a result of not having enough time to pass since the fall vaccine. Other good news is that in vitro studies suggest that the current monovalent vaccine is likely to protect against newer variants.

The official recommendations from CDC now state

Special situation for people ages 65 years and older: People ages 65 years and older should receive 1 additional dose of any updated (2023–2024 Formula) COVID-19 vaccine (i.e., Moderna, Novavax, Pfizer-BioNTech) at least 4 months following the previous dose of updated (2023–2024 Formula) COVID-19 vaccine. For initial vaccination with Novavax COVID-19 Vaccine, the 2-dose series should be completed before administration of the additional dose.

That "should" wording was the subject of much debate, finally choosing this wording more for simplicity of recommendations. The gnashing of teeth came about for a good reason - people in the lower end of this age population who do not have underlying risk factors will have less benefit from a spring vaccine because rates of bad outcomes in the post-pandemic period are lower.

Recommendations for younger people with moderate or severe immunocompromise have slightly different wording:

People ages 12–64 years who are moderately or severely immunocompromised may receive 1 additional dose of any updated (2023–2024 Formula) COVID-19 vaccine (i.e., Moderna, Novavax, Pfizer-BioNTech) at least 2 months after the last dose of updated (2023–2024 Formula) COVID-19 vaccine indicated in Table 2. Further additional doses may be administered, informed by the clinical judgement of a healthcare provider and personal preference and circumstances. Any further additional doses should be administered at least 2 months after the last updated (2023–2024 Formula) COVID-19 vaccine dose.
People ages 65 years and older who are moderately or severely immunocompromised should receive 1 additional dose of any updated (2023–2024 Formula) COVID-19 vaccine (i.e., Moderna, Novavax, Pfizer-BioNTech) at least 2 months after the last dose of updated (2023–2024 Formula) vaccine indicated in Table 2. Further additional doses may be administered, informed by the clinical judgement of a healthcare provider and personal preference and circumstances. Any further additional doses should be administered at least 2 months after the last updated (2023–2024 Formula) COVID-19 vaccine dose.
For all age groups, the dosage for the additional doses is as follows: Moderna, 0.5 mL/50 ug; Novavax, 0.5 mL/5 ug rS protein and 50 ug Matrix-M adjuvant; Pfizer-BioNTech, 0.3 mL/30 ug.

As an aside and not receiving much media attention, a new report showed that vaccine mandates didn't help and probably hurt. States with vaccine mandates didn't have higher covid vaccination rates and actually had lower covid booster uptake and flu vaccination rates. Yikes!

Nipah Virus

Never heard of it, or hard-pressed to find facts at the tip of your tongue? Most providers in the US don't need to know much about this bat-borne virus, but if you have any patients planning a trip to Bangladesh you may want to advise them not to consume raw date palm sap (not on my list of delicacies so far) and to stay away from pigs.

NiV gets its name from the village of Sugai Nipah in Malaysia, site of a 1999 outbreak highlighted by cases of encephalitis in pig farmers. Outbreaks typically occur in Bangladesh and India. Now, the World Health Organization reports that 2 individuals, including a 3-year-old girl, have died from the infection after consuming raw date palm sap. The sap likely was contaminated with fruit bat droppings laced with NiV. In addition to signs and symptoms of encephalitis, typical findings are those of nonspecific febrile illness. Diagnosis is difficult until/unless encephalitis findings appear. It's a relatively uncommon infection even in Bangladesh, but mortality is high.

Good Attitudes

It's a sign of our times that I was pleasantly surprised to see a vaccine attitude survey with good news. Investigators from RAND corporation, University of Iowa, and CDC performed an online survey of 1351 parents to assess their willingness to have their children 5-18 years of age receive a vaccine to prevent Lyme disease. About two-thirds of parents definitely or probably would vaccinate their children. The boldface numbers below show statistically significant predictors of willingness to have their children receive Lyme vaccine, with willingness of the parent to receive the vaccine the strongest predictor.

In case you were wondering, for the purposes of this survey the high incidence states were Connecticut, Delaware, Maine, Maryland, Massachusetts, Minnesota, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, Virginia, Washington D.C. (yes, I don't need to be reminded it's not a state), West Virginia, and Wisconsin. They also looked at states characterized as "emerging" Lyme disease states (Iowa, Ohio, Illinois, Indiana, Michigan, North Carolina), but this group had a slightly lower rate of willingness than in high incidence states. Lyme vaccine trials in the pediatric and adult populations are ongoing, so don't be surprised if parents and children have this option in the next year or so.

Speaking of attitudes, take a look at AAP's new guidance for improving vaccine communication and uptake. It has an excellent literature review and describes various strategies that pediatric healthcare providers can use to improve vaccine acceptance. It is still true that different studies sometimes have reported different conclusions on how best to discuss vaccine hesitancy with parents, likely because it is very difficult to design studies that deal with such subjective issues in a uniform manner.

WRIS

Winter respiratory infection season is still chugging along, mostly due to influenza which is stubbornly persisting in scattered areas in the US. What a crazy patchwork!

New Covid Isolation Guidelines

Maybe this has overshadowed everything in the news. I've discussed this recently in the blog and was expecting the new guidelines to come in April, but CDC bumped it up by a month. It incorporates new information about covid epidemiology, hospitalization rates, and outcomes with balancing for impacts on the economy and on school and work attendance into a comprehensive guideline for all respiratory infections. So, no longer do we have a specific number of days after covid diagnosis to remain out of school or work. The document has multiple links and is pretty complicated. The CDC's press release is a good summary, however. Note that vaccination is still stressed heavily, though I expect it will be ignored by the same hardcore group of antivaxxers. Here's the quick blurb:

"When people get sick with a respiratory virus, the updated guidance recommends that they stay home and away from others. For people with COVID-19 and influenza, treatment is available and can lessen symptoms and lower the risk of severe illness. The recommendations suggest returning to normal activities when, for at least 24 hours, symptoms are improving overall, and if a fever was present, it has been gone without use of a fever-reducing medication."

I am very much in favor of these new recommendations. Circumstances have changed, and we have learned a lot from management of the pandemic these past few years. I just hope our vaccination rate will improve and that people with any respiratory symptoms at all will be aware that they can pose a significant risk to others who may have circumstances putting them at high risk for hospitalization or death from respiratory viruses. Also, please note this only applies to community settings; there are no changes for healthcare settings.

Squirrel Redux

If I were superstitious, I wouldn't mention the fact that my neighborhood squirrels still have not attacked my newly-positioned bird feeder. I was bemused by an article in the Local Living section of the Washington Post last Thursday, clearly written by a squirrel lover. Squirrels do have value, and I have no desire to wipe them off the face of the earth. I just don't want them eating all my bird seed.

A friend of mine in South Carolina with an array of bird feeders and birds also has come to terms with squirrels, albeit somewhat differently than my crazy solution. He just monitors things, and when the squirrels reach a point that he feels they become a significant barrier to maintaining bird happiness and seed access, he uses a humane trap to collect squirrels and then release them far from his neighborhood. I won't disclose where he releases them, but it sounded like a good place for squirrels and unlikely to bother too many people. I wonder if any of them found their way back to him.

A downy woodpecker said hello to me last week.

Month: March 2024