influenza vaccine – Pediatric Infection Connection

One More Time This Summer

Bud WiedermannAugust 25, 2024August 25, 2024Leave a comment

Summer is supposed to be the slowest season in my line of work, but it doesn't seem like it. I've had trouble keeping up with everything, including some old news that I just found out about today. Maurice Williams died on August 5. If that name doesn't ring a bell, stay tuned. Here's what's up for this last post of the summer.

Mpox

It looks like we can add Gabon to the list of countries with exported mpox, this in a 30-year-old man who had stayed in Uganda for 2 weeks. The notice doesn't state whether or not this is clade I, but given that it appears to have been acquired in Uganda there is a good chance that it is. The latest WHO news was posted on August 22, the same day we heard from the CDC about the US response.

By no means is this the next pandemic, but we are seeing global spread of the clade I strain via travelers. Most important is ensuring affected African countries receive adequate vaccine supplies soon. In the US, persons in high risk groups also should be vaccinated.

Measles Check-In

Oregon is the latest state in the measles outbreak spotlight. Nationally the cases are percolating along at a steady rate.

West Nile Virus

In my post last July 28, I was halfway kidding about waiting for symptoms of West Nile virus after all my mosquito bites. West Nile is in "full swing" in Europe currently. Now I see in today's Washington Post that Tony Fauci is back home after a 6-day hospitalization for West Nile infection. Although he is 83 years of age, that's a long hospitalization and I hope he didn't have serious neurologic or other complications. I wish him a speedy recovery.

A little trivia piece I discovered years ago, did you know West Nile virus was tried as a cancer treatment in the early 1950's? Research on using flaviviruses as oncolytic agents continues. Unfortunately the lead investigator of that 50's study is mostly remembered for a serious ethical breach, injecting tumor cells into prisoners to study tumor immunology.

Timing is Everything

I have a complicated plan for how I'm going to time when I get my flu and covid vaccines in the coming weeks, based on travel plans and guessing about peak flu season. At my age, waning immunity following vaccination could be clinically significant.

This brings me to an interesting study in the BMJ trying to define optimal timing for influenza vaccination in young children. It utilized data from an administrative database in the US for timing of vaccination of over 800,000 children ages 2-5 years during several flu seasons. Bottom line, it looked like October was optimal. I wouldn't necessarily alter plans based on this study; every flu season has slightly different timing. It's probably a better plan to just vaccinate when you can, whether it be at regular checkups or flu vaccine events on evenings and weekends.

Holding My Breath on Polio

I'm still hoping polio doesn't break loose in Gaza, but I'd be more hopeful if vaccine could be distributed there. WHO has full plans in place to distribute the relatively new novel oral polio vaccine type 2 (nOPV2) to about 640,000 children under 10 years of age in 2 campaigns separated by a month. Wastewater monitoring suggests this is the strain that caused the case recently detected in a child in Gaza; we're still waiting for confirmation from a regional lab in Lebanon. Now we just need an effective ceasefire to allow this and other humanitarian aid to be implemented.

Covid

The big news was the not surprising FDA approval and emergency use authorization of the KP.2-based mRNA vaccines from Pfizer and Moderna. Novavax approval is still pending due to a longer manufacturing process. As I've said many times, if one looks at the level of individuals, it's pretty clear that vaccination benefits outweigh risks for every age group. New interim recommendations are available from the CDC.

Here's a quick look at a few disease activity indicators over the past year:

Wastewater hasn't changed much nationally.

Regionally, only the Northeast seems to be rising, though still lower than most other regions.

We'll see what happens with covid (and measles) now that schools are starting back again.

In the midst of all this, we have a new study on long covid in children. It was a multicenter prospective cohort study of about 900 younger children and 4500 adolescents, most with covid infection but some not infected who served as controls. The report is loaded with data and complexities; I'm sure everyone in the field is looking it over closely.

It's tough to summarize the findings succinctly, but perhaps you can enlarge the figure below to see details. The darker color shades are the more prominent symptoms in each cluster. Clustering of types of symptoms varied between adolescents (12-17 years) and school-age children (6-11 years). I'm very happy to see this type of analysis; it is possible that different clusters have different pathogenetic mechanisms suggesting different treatment approaches. Clusters in the younger children were in the neurocognitive, pain, and GI domains, whereas loss of smell or taste, pain, and fatigue/malaise were highlighted for the adolescents.

This study won't change clinical practice immediately, but it is a major step forward in providing a framework to base treatment studies.

"No Good Songs Ever Came Out of the 1950s"

That probably inaccurate quote, heard when I switched my car's Sirius/XM to the 50's station, came from a musically-inclined and knowledgeable friend of mine. I'm pretty sure he uttered it just to get a rise out of me, which it did. IMHO, the 50's produced a lot of good songs and shouldn't be remembered just for some wacky West Nile virus studies.

The title of this week's post is a nod to Maurice Williams who wrote the song "Stay" in my birth year, 1953, but then put it on the shelf until he recorded it with the Zodiacs in 1959. It came out in 1960 and was a big hit at just 90 seconds in length. You may be more familiar with it from the 1977 cover with slightly altered lyrics by Jackson Browne, Rosemary Butler, and David Lindley (and the 9-minute mini-medley with "The Load Out") or from the 1987 movie "Dirty Dancing" that used the Williams original. Regardless of which of the couple dozen versions I listen to, this is one of those songs that always brings a smile to my face.

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.

Bug Art 2

Bud WiedermannNovember 26, 2023November 26, 20232 Comments

I hope everyone had a wonderful Thanksgiving holiday, I know I did. With 4 physicians and 2 other medical professionals at the the table this year, our family went through the usual dressing/stuffing discussions with risk of undercooking the stuffing resulting in higher salmonellosis risk. We remain asymptomatic.

Recently I watched a 3-part PBS series about the artist Frido Kahlo. It also featured her sometimes-husband, Diego Rivera, prominently; he was a better known artist than Kahlo for much of the 20th century. Little did I know, until a hot-off-the-presses review article, that he had a bit of microbiologic art featured in some of his works.

First, let's look at what's been going on, besides Thanksgiving, this past week.

Strep Throat Should Be Simple

Every now and then I go on a rant about strep throat. Of course sore throat is very common, and it sounds like a simple problem, but in fact it is one of the most poorly understood maladies I deal with. The combination of a common clinical problem with a pathophysiologic basis full of lacunae has resulted in generally poor management, most conspicuously in antibiotic overuse. The biggest problem is trying to determine someone who tests positive for GAS is just a streptococcal carrier who really has viral pharyngitis from someone with true streptococcal pharyngitis who would benefit from antibiotic treatment. With rare exceptions, identifying a streptococcal carrier is of no clinical utility and only serves to increase unnecessary antibiotic use. We badly need better diagnostic tools (both clinical and laboratory) as well as a better understanding of drivers of serious sequelae such as invasive disease and post-streptococcal arthritis, rheumatic fever, and glomerulonephritis.

Now we have a very intriguing study of essentially healthy children presenting with sore throat and then followed as a prospective cohort for 2 years, looking specifically at antigen testing, throat culture, streptococcal antibody levels, and outcomes. It was mainly designed to provide a framework with which to test upcoming vaccines for group A streptococcus - if you don't have accurate inclusion criteria and outcomes, it's pretty tough to measure vaccine effectiveness. I want to also mention here that of the 8 authors, only 1 was an actual clinician; the rest were all employees of a pharmaceutical company that develops vaccines. Normally that degree of for-profit pharma involvement in a trial would raise concern for implicitly biased interpretations of the results, but in this case we don't have a vaccine product involved in the study so perhaps less for me to fret about.

Children could be enrolled if they were from 3 to 12 years of age and did not have circumstances that could alter conclusions, including no documented group A streptococcal infections in the 6 months preceding study entry. Here's the protocol at study entry at the time of presentation with sore throat (RADT denotes a rapid antigen test for GAS):

Study subjects then had healthy visits at 3-month intervals for the remainder of the 2 years, as long as it was at least 6 weeks following sick visits. At the healthy visits they had throat culture for GAS, but not RADT, obtained. Serology for the sick visits included blood for antistreptolysin O, anti-DNase B, and antistreptococcal C5a peptidase antibodies. If GAS pharyngitis was diagnosed at sick visit 1, the children were treated as per standard by their clinician.

Definitions are important here. A GAS carrier was defined as a positive healthy visit GAS culture plus a positive RADT or culture at sick visit 1 that remained positive at sick visit 2 which occurred 7-10 days after completion of antibiotic therapy for the sore throat event. The researchers evaluated several definitions for GAS pharyngitis which I copy here:

I provide a lot of background for the study methods because they seem very well considered to me, plus I think it is helpful for clinicians to consider all of these possible case definitions when evaluating children with pharyngitis.

Now for the results. First, streptococcal antibody measurement is mostly useless to distinguish true infection from carrier state. That could have been predicted from multiple prior studies but is particularly important in monitoring antibody response in vaccine trials.

Don't look to this study to change your clinical practice if you already follow guidelines for management of GAS pharyngitis. What it does show is how difficult it will be to design trials for future GAS vaccine effectiveness. In the 1960s, a GAS vaccine likely caused an increase of acute rheumatic fever-like illness in vaccine recipients, and GAS vaccine development has been appropriately cautious since that time. GAS vaccine safety issues have been reviewed recently.

Also be aware that I had a few questions about the study that weren't addressed in the publication or the accompanying online supplemental information. I've emailed the first author, the one clinician in the study, and if I hear back I'll provide updates.

It's Beginning to Look a Lot Like ...

.... winter respiratory virus season. RSV, influenza (sorry, at the time I'm writing this we have no new FLUVIEW updates since the week ending November 11), and to a lesser extent wastewater covid all are on the upswing,

It doesn't qualify as a tripledemic yet, but stay tuned.

The Verdict on Last Season's Flu Vaccine

The 2022-23 influenza season was a bad one for pediatric hospitalizations, but we now have some final data on how well the influenza vaccine prevented such episodes.

The vaccine effectiveness is pretty good, in line with other seasons for the most part. The low vaccination rates are another key takeaway; I wish this would improve, but I'm not optimistic given the current upswing in vaccine hesitancy.

Holiday Season Puzzler

Here's a glimpse of Figure 2 from the Rivera review article. As you emerge from what I hope was a wonderful Thanksgiving holiday, see if you can identify the types of organisms that are depicted.

Happy St. Martin’s Day

Bud WiedermannNovember 12, 2023November 12, 2023Leave a comment

I was thumbing through my Farmer's Almanac this morning and noticed a mention of "Indian summer" for November 12. That's not a great term to use nowadays, so I'm opting for the European version called St. Martin's summer or day. I never bothered to see what these terms really meant, but I've learned it represents a period officially from November 11 to November 20 where we experience unseasonably warm weather. We've certainly had that recently, though November 11 and 12 in Maryland is back to cool fall weather.

Miscellaneous Vaccine News

I have no idea what a "miscellaneous" vaccine is, I was just desperate for something to title this section.

A new vaccine to prevent chikungunya virus infection was approved by the FDA this week for individuals 18 years and older at increased risk for infection with this mosquito-borne pathogen. It is a live virus vaccine. As with most arboviral illnesses these days, the vector range is expanding as our climate warms, and transmission has occurred within the US. Still, most infections in US residents are acquired via travel to more endemic areas such as Africa, southeast Asia, and Central and South America. The clinical illness is similar to dengue fever and mostly is a miserable but self-limited illness. However, elderly are at risk for complications, principally chronic joint disease. Newborns also are at risk for more severe disease, including death, and it is unknown whether the vaccine virus could be transmitted to the fetus. The package insert includes precautions for use in pregnant people. The main study supporting approval appeared a few months ago and looked primarily at side effects and antibody response, not actual vaccine efficacy. One big caveat, the manufacturer is required to conduct post-marketing studies to ensure that vaccine recipients do not develop a worse form of chikungunya after becoming infected; this is a possibility though not highly likely. For now, I'd consider this mostly as an option for older individuals at very high risk for infection. Most other US residents should wait for further information about the vaccine, but it's good we have this option available.

This past week also saw publication of new data from Singapore about benefits to newborns of covid vaccination of mothers during pregnancy. It was a cohort study, which is a study design slightly more prone to inaccuracies than are randomized controlled trials, but it did show about 40% efficacy in preventing infection in newborns when their mothers were vaccinated during pregnancy. Of interest, pre-pregnancy vaccination of mothers was not effective in preventing newborn infection. The study covered the period from January, 2022, through March 2023. This is yet another reason to encourage covid vaccination for pregnant people, along with pertussis and RSV vaccination. The benefits do extend to their children.

Unfortunately, we also have some disappointing vaccine news in the category of missed opportunities. First, 2 studies from the CDC demonstrated poor influenza vaccine uptake by healthcare providers. In the first report, flu vaccination rates for HCP in acute care hospitals fell from 88.6 - 90.7% in the years 2017-2020 down to 85.9% in 2020-2021 and 81.1% in 2021-2022. We all know that the pandemic made it difficult to access regular health care for many people, but these are workers in acute care hospitals who didn't have that excuse. The second study looked at a broader range of HCP during the 2022-2023 flu season and showed 81.0% flu vaccination rates in acute care hospital employees and a shocking (to me) 47.1% rate for nursing home employees. Up to date covid vaccination status rates were even more depressing: 17.2% and 22.8% in acute care hospitals and nursing homes, respectively. I can understand why some people may choose not to receive these vaccines, but HCP do have a responsibility to protect those for whom they provide care. (IMHO; I'll get off my soap box now.)

Also in the Debbie Downer category, CDC reported that vaccine exemptions for kindergarteners increased for the 2022-2023 school year. The rogues' gallery includes 10 states (Alaska, Arizona, Hawaii, Idaho, Michigan, Nevada, North Dakota, Oregon, Utah, and Wisconsin) having exemption rates above 5%. Idaho easily came out on "top" with a 12.1% exemption rate. The reasons for high exemption rates are complex, note that the list of states doesn't necessarily follow political lines. States that make it more difficult for parents to apply for non-medical, aka philosophical, exemptions have lower exemption rates overall. An oldie but goodie study also stressed that exemption rates vary within a state, and small hot spots with high exemption rates can fuel outbreaks of vaccine-preventable diseases.

Missed Opportunities to Prevent Congenital Syphilis

The CDC was very busy this past week! Another report looked at missed opportunities for prevention of congenital syphilis in 2022. Looking at the 3761 cases of congenital syphilis reported that year, almost 90% of birth parents received inadequate management. This included no or nontimely testing (36.8% of parents) and no or nondocumented (11.2%) or inadequate (39.7%) treatment. I'm hoping our public health infrastructure can be shored up to lower cases of congenital syphilis, now at a 30-year high.

Tripledemic Update

Rather than showing yet another RSV-NET graph, where data are somewhat delayed anyway, I thought I'd mention a bit more about that system. It is set up in 14 states covering about 8% of the US population. Here's what the distribution and data collection looks like:

I'm not sure why (Veteran's Day?) but FLUVIEW did not update this past week, so nothing new to report there. Wastewater covid levels reported by Biobot remain lowish.

No Hasty Pudding Again This Year

I'm starting to help plan a Thanksgiving menu for later this month, and I was reminded of another ill-named item, Indian pudding. It is similar to the British hasty pudding that uses wheat flour rather than cornmeal. I have a wonderful recipe, dated 1958, from the Durgin-Park Restaurant in Boston. Durgin-Park opened in 1742 and closed in 2019, and this dessert was an icon on their menu. The reasons I won't be having it again this year are multiple but include the fact that I'm the only one in my family who likes it and that it contains about 5000 calories per tablespoon (only slight exaggeration). I think I'll just change the name to Durgin-Park pudding for future reference.

Going on Standby

Bud WiedermannMay 7, 2023May 7, 2023Leave a comment

The covid state of emergency has ended, both globally and in the US (the latter officially on May 11). On May 4, the director general of the World Health Organization, Dr. Tedros Adhanom Ghebreyesus, declared that covid is now an established and ongoing health issue that no longer requires resources needed for a public health emergency of international concern (known in the business as PHEIC). Future planning from the WHO is now detailed in a new document, the 2023-2025 COVID-19 Strategic Preparedness and Response Plan. It weighs in at only 20 pages, so needless to say it is short on details. For that, you'll need to dig into the document links.

Meanwhile in the US, our official emergency will end on May 11 as previously planned. So far we don't have any true future response plan.

Funding for Vaccines, Medications, and Tests

The official end of the emergency eventually means that the general public won't have access to free covid vaccines, medications and diagnostic tests. Naturally this varies with insurance type and also timing; any products still in circulation that were provided by the feds will remain free, but I haven't seen any estimates yet on how long these supplies will last. Nothing will really change for patients on Medicaid until September 2024, although access to Medicaid itself could change. The Infectious Diseases Society of America (IDSA) produced a nice table briefly outlining the situation. Unfortunately it's too big to copy well below, but a pdf version is available for download. Note that this all is completely separate from FDA's Emergency Use Authorization for vaccines, medications, and devices, which won't change until industry applications for full approval are submitted and evaluated.

Covid Vaccine Updates

First, I very much apologize for not mentioning in last week's post that the FDA on April 28 did make some allowances for additional vaccine doses for immunocompromised children. CDC has now posted this update in their Interim Clinical Considerations website for covid vaccination. Basically, any significantly immunocompromised person 6 months of age and older can receive additional bivalent vaccine, number of doses depending on prior vaccination status but also giving much leeway to the healthcare provider. Sadly, the site is still very messy, not user friendly for providers or individuals. CDC and IDSA did have a webinar on May 4 with some nicer graphics in some slides, but so far I've been unable to find the same graphics on the CDC website. Here's the quick look at vaccination for immunocompetent children ages 6 months to 4 years, and also for that "awkward" age of 5 years when the cutoffs for Pfizer and Moderna vaccines are different. You can download or watch the presentation yourself at the IDSA site.

The next major step for covid vaccines will be a meeting of the FDA's Vaccines and Related Biological Products Advisory Council (VRBPAC) on June 15. At that time the composition for the next vaccine will be determined, in time for a potential release in fall of 2023. The FDA's plan for subsequent covid vaccine adjustments was presented by Dr. Peter Marks, director of FDA's Center for Biologics Evaluation and Research, at the same May 4 IDSA meeting mentioned above. It is very similar to the process for annual influenza vaccine composition.

Covid Tracking Changes

We've been in more of a bind the past several months trying to track covid cases in an era of public exhaustion with the pandemic as well as non-reporting of home testing results. Additionally, CDC and local/state health departments have lessened their efforts, and most non-governmental groups have discontinued intense tracking as well. We are mostly left with tracking easily measurable data that probably are a good surrogate, at least for severe infections. Hospitalization rates for covid have been quite low for all age groups recently.

On May 5 CDC released 2 MMWR articles to clarify and justify tracking changes. Primary surveillance now will consist of the weekly hospitalization rates above as well as percentage of deaths attributed to covid. Secondary indicators are emergency department visits and percentage of positive covid testing in laboratories. Genomic and wastewater surveillance will be used to track variants. In the past, many of these outcomes have reflected in a timely manner the covid community levels when tracking of infection was more reliable, so perhaps it's not a bad trade off. Time will tell.

Other Changes and Events

The news has been saturated with Dr. Rochelle Walensky's announcement that she will step down as CDC director effective June 30. The announcement was short on rationale for the change. Previously Dr. Walensky had announced new strategic planning to revise CDC's structure and management, a badly needed overhaul. I hope this plan won't fall apart with her departure.

As I mentioned in a February posting, work on RSV vaccines is advancing, most recently with FDA approval of one vaccine for individuals 60 years of age and over. CDC and ACIP are expected to make recommendations at their June 21-23 meeting. Flu vaccine composition also will be discussed. In the meantime, FDA VRBPAC will discuss RSV vaccination of pregnant women to prevent or modify illness in newborns at their May 18 meeting.

Lastly, you may have seen press reports of a meeting of scientific advisors with the White House that attempted to put a number on the likelihood that we'll experience another big wave of covid in the next 2 years. Like all covid forecasts, many assumptions are made to produce such numbers and really should be accompanied by a sensitivity analysis that varies the assumptions so that we have a better range of what to expect. I haven't seen an actual publication for this latest estimate so can't really comment further.

My Book Report

I've been working on a book review that I hope to have completed in time for next week's blog. I'm also trying to remember when the last time was that I wrote a book report, probably elementary school. Stay tuned.

Tag: influenza vaccine