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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 1264 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.

Famous golfer Tiger Woods couldn't complete the second round of a golf tournament this weekend due to influenza. Two questions came to my mind immediately, still not answered. But, we have a lot more than golf to discuss this week.

WRIS

I suspect we are a matter of weeks away before I can retire Winter Respiratory Infection Season as a weekly feature. RSV is much less of a factor now, and I won't be discussing much about RSV unless things change.

Influenza-like illness continues to fluctuate regionally, we're really seeing wide variations. I'll mention again that this tracking method will pick up not just influenza, but also other respiratory illnesses. However, pre-pandemic it was a pretty reliable gauge of influenza activity. I do note that Mr. Woods lives in Florida and the golf tournament is in California. He became ill Thursday night, so using the common incubation period for flu of 2-3 days he could have acquired this in California (if he was practicing there a few days before); however, the outer range for flu incubation period is 7 days, so all bets are off about where he met his virus. (Also, I'm not stalking him, I have no idea about his travel history.)

At this stage of flu season, it's worth a look at pediatric mortality numbers. It's a little less than, but similar to, last year. Also note there is a significant lag time in reporting and verifying influenza deaths, so some of these bars in previous weeks will rise.

Pediatric deaths continue to occur slightly more commonly in children without underlying medical conditions, and the 5-11 year age group is the most common. Unfortunately, no data for vaccine status is provided.

What about the covid scene? As usual, I'm still looking at wastewater data because the methodology for collecting and reporting this information hasn't changed as much as have the methods for reporting infections and deaths among the states.

Again, this is at most a qualitative descriptor, but nothing to suggest a new surge approaching. Wastewater activity is highest in the South.

I wish CDC would publish numbers of covid pediatric deaths like they do for influenza. They only report death rates per 100,000 by age, and of course they are very low for the pediatric population. The absolute numbers are somewhere in there, but on the CDC website it would require me to write my own search language in their database, and I'm too lazy to spend the time to figure that out.

I also took a look at CDC's covid vaccine rates by age, especially since they now have updated information regarding the fall XBB vaccine dose. It's pretty grim.

Note that the highest rate is only 13.4%, and when I dug down into more details, all the states except one were in single digits for pediatric populations receiving the updated vaccine. The best and only double-digit rate was Vermont at a dismal 13.4%.

On the other hand, one could argue that because rates of serious pediatric disease with covid are so low it isn't cost-effective to vaccinate children who do not have risk factors. In fact, that's what most countries have decided; the US is an outlier in offering covid vaccine to healthy children. Nonetheless, on an individual basis every child is better off being vaccinated than not, even given the low risk of death, long covid, MIS-C, etc.

Back in the somewhat good news arena, a recent article gave an overview of planning (and funding!) for research on better covid vaccines, monoclonal antibodies, and antiviral drugs that will not be subject to loss of effectiveness with new variants. It's called Project NexGen.

Lastly on the covid front, many of you probably heard about CDC plans to change isolation guidelines for the public to be more in line with what we do for flu and other respiratory viruses. So far it is just a draft, but it's targeted for release in April. It's not really based on any new findings about transmission rates or duration of infectivity, but rather I think an attempt at simplicity with the recognition that current guidelines aren't being followed by the majority of the public anyway. What I think is most important, and I hope the final guidelines will stress, is that guidelines should differ depending on the situation. For example, it's a very different calculus for children attending school than it is for those same children going to visit their 85-year-old grandma. The public needs to understand that different risks occur in different circumstances.

Measles

Hot off the presses, 4 children in a single elementary school in Florida developed measles. So far not much official from the Broward County health department, but I'm betting that none of them were fully immunized. Watch out for a large number of secondary cases in the coming weeks.

Changes in Prophylaxis for Meningococcal Disease

This was news from the previous week that I'm just mentioning now. Ciprofloxacin has been used for prophylaxis of meningococcal disease for several years, but recently some sectors are now seeing resistance to quinolones. So, if you are considering prophylaxis of a close contact of someone with meningococcal disease, you will need to contact your local health department immediately to see if the resistance rate meets criteria for choosing an alternative agent such as rifampin, ceftriaxone, or azithromycin.

Tiger's Third Degree

I look at everything through an infectious diseases eye, whether I'm walking down the street, reading the paper, or chasing squirrels from the bird feeder; I just can't stop myself. So, I have 2 questions for Tiger.

  1. Did you get a flu vaccine this year? I'm not a betting man, and I've already made one bet in this blog, but I'd guess not. He had fever and other symptoms the night before his Friday golf round, and then Friday morning still had fever and other symptoms but tried to play the round, making it through a few holes before feeling faint and ending up with IV rehydration therapy according to his official statement.
  2. And to follow up on the above thought, what were you thinking trying to play the round on Friday? Not only did you not meet any school or workplace criteria for participating, you exposed everyone close to you to influenza presumably without notifying them. Of course, this is the sort of "tough it out" mentality that I've been guilty of myself in the past, at least to the point of working when I had a mild cold because I thought myself too essential for my workplace or didn't want to shoulder my colleagues with covering me. I don't think Tiger needed the money for playing in the tournament, but he also was the host of this particular event and I'm sure many fans turned out primarily because he was playing, so that's a bit more pressure than in my workplace. Still, isn't it time we made a change in our behavior when we're sick? Take a moment to think about the impact your actions have on others.

Which brings me to a third question for Mr. Woods: Would you at least make a statement recognizing that you should not have tried to play on Friday, and also give a plug for flu vaccine even if you didn't receive one this year?

I'd bet big bucks that Tiger Woods doesn't read this blog, so, yes, I'm just blowing off steam.

Next week is the regular meeting of the ACIP, I"m hoping to view most of the 2-day meeting and have this be the focus of next week's blog.

I've been a Super Bowl addict I think from Super Bowl I, persisting in spite of the fact that the NFL has done very little to limit head trauma and chronic traumatic encephalopathy. I'm usually tied to the Super Bowl screen almost continuously because I like to pay particular attention to the national anthem (more on that later) and to all the commercials. For Super Bowl LVIII I'll unfortunately need to grimace and grit my teeth when the Kansas City fans do their insensitive tomahawk chopping and war hooping.

As I rush to finish my long list of chores for today I somehow need to cull through this week's list of 16 blog topic ideas to post something with low soporific properties. Here goes.

I'm Beginning to Really Worry About Measles

It's difficult to find a central, accurate source of data, but it seems to me that an unprecedented level of sites around the world are experiencing high numbers of measles cases. Coupled with robust international travel, declining vaccine rates, and very high contagion, the US population could have a major resurgence.

An editorial in the BMJ last week (unfortunately freely available only to those with a subscription) re-sounded the alarm. The impetus was a new outbreak in the West Midlands, but really the problem has been sweeping Europe for at least a year. They quote other sources citing over 42,000 cases in European Union countries from January to November 2023, with 5 fatalities. Ireland, which had only a few measles cases in 2022 and 2023, reported the death of a middle-aged man who had visited Birmingham; no further details such as underlying risk factors are available presently. Our northern neighbors in Montreal report a measles case in an unimmunized child, likely acquired on a trip to Africa. The child's age isn't mentioned but he was apparently school-aged since a school is one of multiple sites where health authorities are trying to track down contacts.

I came across an updated measles website from the Infectious Diseases Society of America that I think is pretty helpful, including several links to other sites. Look at the Facts link for a good discussion of common measles misconceptions. And, please, please, please make sure all your eligible pediatric patients are immunized.

Speaking of Vaccine-Preventable Diseases

Diphtheria has killed 130 Somali children in the last 3 months, according to a news report. Antitoxin availability in the country is very limited. Diphtheria continues to pop up in resource-poor countries with ever-present risk of imported and then locally-acquired cases appearing in the US.

"Silent" ARF

A new study carried out in Sudan informed me about the existence of "silent" acute rheumatic fever. The investigators performed handheld echocardiography testing on 400 febrile children 3-18 years of age who did not have a definite etiology for their fever. Of 281 children who had no clinical features of ARF, 44 had evidence of rheumatic heart disease on echocardiogram. This is an interesting diagnostic intervention that could prove practical for use in high risk ARF countries, but costs and training could be significant barriers.

Thankfully we don't have much of a rheumatic fever problem in the US, likely because most endemic US group A streptococcal strains are unlikely to trigger ARF. However, imported strains certainly pose a risk, and evaluation of any suspected ARF case should take into account travel history/country of origin.

More on Treatment of Hearing Loss in Congenital CMV Infection

Last week I mentioned a small phase 2 study of late, short course treatment for children with hearing loss likely due to congenital CMV infection; it didn't work. Now this week we have a report of a small phase 3 study in the Netherlands. It was an unusual circumstance where a randomized trial was converted to a non-randomized trial because the original trial floundered due to lack of enrollment; most parents wanted their children to receive treatment. In the new study, children with hearing loss but otherwise clinically silent congenital CMV infection received either 6 weeks of oral valganciclovir (n=25) or no treatment (n=15). They were followed until 18-22 months of age, and the treatment group had less hearing deterioration than did the control group. Not the cleanest study but a better design overall than was the US study, and it did find evidence of benefit. This also points out the great difficulty in conducting these trials; even though congenital CMV infection is very common and virtually all US infants are screened for hearing loss, it's very difficult to enroll and follow-up these children in randomized double-blind placebo-controlled trials. We still don't have a definitive answer on treatment benefits for isolated hearing loss in congenital CMV, but I hope the investigators don't give up trying.

Alaskapox

No, I didn't make up that word, it's a real orthopoxvirus that can rarely infect humans mostly in, you guessed it, Alaska. Only 7 human cases are known to exist, but the most recent one, in an immunocompromised man, was fatal. The report also is striking for how long it took to diagnose him. The virus mainly infects small mammals (voles, shrews) with no known human-to-human transmission so far. However, there is no reason it wouldn't be spread from another human, just like other viruses (smallpox, cowpox, Mpox) in the same family.

Photo from https://health.alaska.gov/dph/Epi/id/SiteAssets/Pages/Alaskapox/Alaskapox-FAQ.pdf.

New Syphilis Testing Guidance

CDC released new recommendations for laboratory testing for syphilis, good timing given our terrible syphilis epidemic in the US. It is highly technical, so mostly of interest to laboratorians and syphilis geeks like me. Some of the illustrations and graphs are useful for everyone. Here is a nice quick view of lab test results in various syphilis stages:

And an explanation of the prozone effect, very important and something that I've found not all hospital clinical lab personnel understand. It appears mostly with RPR testing, where very high antibody levels cause a false negative result unless the assay is run at higher dilutions.

WRIS

Not a whole lot new with the Winter Respiratory Infection Season.

Investigators in France reported that rhinovirus infection in infants was a major contributor to bronchiolitis hospitalizations pre- and during the pandemic. Here's an example of ventilator use for RSV and rhinovirus during 2019 - 2020.

From a practical standpoint we have a tough time sorting this out with commercially-available testing. PCR testing for rhinovirus uses primers that include most enteroviruses, so you will always see these results combined as rhinovirus/enterovirus with no way to separate out which is which. The problem is compounded because most enteroviruses normally persist in the body and in nasal secretions weeks to months after the clinical illness resolves. So, a positive rhino/enterovirus test might reflect an infection that a) occurred months previously, and b) could have been asymptomatic (90+% of enteroviral infections are asymptomatic). Often we can guess rhinoviruses are active if we see a mid-winter bump in rhino/entero positivity, since the usual enterovirus epidemic peak is late summer/early fall.

Of note, the French investigators did not provide details of the PCR assay used in their study, so we are left trusting the journal editors that it did reliably distinguish rhinoviruses from enteroviruses.

RSV is pretty clearly on the way out, though still causing a lot of illness nationwide. The decline is present in all 7 monitoring sites.

Influenza also is declining, with a couple caveats.

First, we are starting to see a higher percentage of influenza B isolates now. This typically happens near the end of flu season, but it could also produce a secondary bump in infections. Second, local and regional flu levels are quite variable - what's true for Maryland is completely different in New Mexico. Also, I've never been a fan of presenting city-level (NYC, DC) data in the same context as state data - a classic apples and oranges comparison.

Covid wastewater data continue to be encouraging.

We also have a few new updates on the covid scene. The UK released their spring vaccine recommendations which are to offer vaccine (usually mRNA XBB.1.5 vaccine unless not suitable for an individual) to adults 75 years of age and older, residents in adult care homes for older people, and anyone 6 months of age or older fulfilling their definition of immunosuppression.

I was pleased to see an update on trying to get a handle on Postacute Sequelae of SARS-CoV-2 in Children (PASC), though as I read through it I still felt it was a difficult jumble of clinical syndromes that make it hard to develop practical management advice anytime soon. Here's an overview of their conceptual model:

I applaud the investigators for continuing to slog through this and I do expect to see concrete advice sometime in the future, not only for PASC but perhaps for all those other post-infections syndromes currently lumped into the myalgic encephalomyelitis/chronic fatigue syndrome wastebasket.

Birdhouse Update

I'm sure everyone has been waiting to hear the latest update in my birdhouse squirrel-proofing adventures. I'm happy to say the birds are back, but so far no squirrels are stealing the birdseed! I did notice one dastardly Scurius representative sitting on the large branch from which the birdhouse was suspended, but it never made an attempt to jump. We'll see how long this holds up.

White-breasted nuthatch enjoying the sun and safflower seeds, unmolested by squirrels.

Super Bowl VIII

Yes, I'm aware it's now LVIII, but much of my Super Bowl roots go back to the one 50 years ago where I happened to be employed selling beer in the stands. I didn't make much money; I was assigned to the Vikings side of the stadium, and they got blown out by the Dolphins and quit buying. I also didn't see much of the game itself due to walking up and down the stands, yelling "cold beer" and looking for raised hands.

I was required to show up several hours before kickoff time, and the stadium was virtually empty. One person on the field that morning happened to be one of my personal heroes, the country singer Charley Pride. (As an ironic note to me, he died of covid complications at age 86, in the first year of the pandemic and before vaccine availability.)

Pride was really the only Black person to have broken through as a country music star at the time, and he was practicing singing the national anthem which he would do at the start of the game. When he finished practicing I walked down to the field level and he was kind enough to chat with me a few minutes. He autographed my flimsy paper vender tag, now lost somewhere during my many moves.

As you can tell, I haven't lost that 50-year-old wonderful memory. Kiss an angel good mornin' if you have a chance. 😉

Washington, DC, had a record high temperature 1 day during our heat wave this past week, and I suppose if you glanced at the sun you might see some spots for a few seconds. But of course I'm referring to different spots in this post.

Measles

I'm probably the only person who has read all of my blog posts over time, so you're forgiven if you don't realize I'm in broken record mode here. I can't count the number of times I've warned providers to be on the lookout for measles cases, and now we are facing a global decline in immunization rates that probably puts us at greatest risk since the modern-day measles vaccine was available in 1968 (the original Enders vaccine appeared in 1963). We've enjoyed some low numbers in the US recently, but that appears to be changing with 9 cases (from Georgia, Missouri, New Jersey, and Pennsylvania) reported to CDC so far this month.

CDC released an alert last week mentioning 23 US cases between December 1 and January 23.

I won't review everything about diagnosis of measles, the CDC website alert is a good resource with links to other sites, but I do want to highlight a few helpful nuances that aren't often mentioned. First, measles is fairly unique among exanthematous infections in that the prodrome interval, the time between onset of first symptoms and appearance of the rash, is long, usually a few days. Most infectious diseases accompanied by rash have very little or no time between onset of symptoms and appearance of the rash, with erythema infectiosum being a notable exception but not easily confused with measles clinically.

The measles prodrome consists of a febrile illness with cough, coryza, conjunctivitis, and Koplik's spots. You can find pictures of Koplik's spots everywhere on the web, but in my experience as an old geezer who has seen many cases of measles in children, they aren't that easy to see or photograph. Therefore, the photos available in textbooks and on line are skewed towards the most obvious. One needs to do a careful oral exam looking for gray or bluish-gray or white fine spots (almost sandpapery) anywhere on the buccal mucosa; the inside of the lower lip is particularly helpful. If you're not sure, find an old geezer clinician to confirm.

In the absence of Koplik spots, or if you don't see the child until the rash appears and the Koplik spots have resolved, pay close attention to the history. Specifically ask for a day-to-day accounting of symptoms; if you feel the parent or patient can recall reliably, noting at least a 2-3 day lag between the onset of high fever, cough, rhinorrhea, and conjunctivitis before the rash appears can be strongly suggestive of measles; the absence of this lag is against the diagnosis. Other alarms to increase your suspicion would be lack of 2 measles immunizations, international travel, and/or exposure to a suspected measles case.

"It ain't what they call you.....

..... it's what you answer to." - attributed to W.C. Fields, though I can't verify the origin.

I thought of Mr. Fields when I heard about administration errors involving the adult RSV vaccine (brand names Abrysvo and Arexvy) given to children and pregnant people. From my viewpoint, it was an accident waiting to happen, due to a name.

In order to speed payment allowance by the Vaccines for Children and other programs, the long-acting monoclonal antibody nirsevimab was officially designated a vaccine. Strictly speaking I guess this is correct: antibody administration is a form of passive immunization. However, the true RSV vaccines are intended only for adults with high risk conditions or for pregnant people to help protect newborns after birth. It was inevitable that confusion would ensue. The notice provides almost no details but does state that most administrations to young infants were "nonserious." Infants who wrongly received an adult RSV vaccine should be considered unprotected and still receive nirsevimab.

WHO Fans the Covid Mask/Distancing Controversy

WHO riled a lot of public health experts with its recent guidance for infection control in healthcare facilities. The main controversial elements involve recommendations to use physical barriers such as plastic windows for areas where patients first present (rated as conditional recommendation, very low certainty of evidence); maintaining a physical distance of at least 1 meter between people ("good practice statement"); and not sufficiently highlighting superiority of respirators (e.g. N95 masks) for general care - this particularly angered those who favor the aerosol, rather than droplet, mode of transmission for SARS-CoV-2. In general it seemed that the WHO panel carried over some details for infection control that do not have strong evidence for use and in some cases (plastic barriers) may be contradicted by other studies.

Note that much of the controversy involves how much weight to give transmission simulation studies - e.g. distances that SARS-CoV-2 travels under experimental conditions rather than real-world evidence which is much more difficult to come by. It's hard for an individual medical practice to make these decisions on their own, best to abide by state or local health department guidance.

Spring Covid Vaccination?

Canada released guidance for covid vaccination this spring, advocating for an additional dose of the XBB.1.5 vaccine recommended last fall. I'd look for the US to make similar recommendations soon. ACIP has a regular meeting scheduled February 28-29, but no agenda is yet available. FDA doesn't have anything scheduled, and they may not need a separate advisory committee meeting for this.

WRIS

In general we seem to be trending downward with our winter respiratory infections, but still lots of runny noses, coughs, and more around.

For RSV I still look primarily at hospitalization rates in young children, the purple line in the graph below, because I think it's the most accurate gauge of RSV. I suspect almost all of these hospitalized children are tested for RSV and flu. The rate clearly is trending down, it's looking like we won't replicate the horrible RSV season of last year.

Influenza-like illness seems to be cooling off as well, as seen in FLUView. Note this measurement includes respiratory illnesses mimicking flu so could be any respiratory virus; there are many more ways to look at flu activity in general, all with their own inaccuracies. In the past I have found this map to be representative of what I've seen clinically in my practice areas.

Covid wastewater (I've said before why I prefer this qualitative measurement) continues to trend downward, and levels are below that seen last year.

All told this is good news for those of you trying to manage your packed patient waiting rooms. Let's just hope you don't have a case of measles sitting in there somewhere!

Do You Even Know What a Broken Record Sounds Like?

I used this term when I said I was sounding like a broken record for repeating over and over my warnings about measles. I harp (pun intended) on this because measles is the most contagious infectious disease known and most younger clinicians in the US have never seen a case, meaning it can be missed easily. However, those same clinicians might never have heard a broken record either. Vinyl records made a bit of a comeback recently but even I no longer have a turntable to play vinyl records; I do have a few moldy vinyl albums from the 1960s and 70s. I'm occasionally tempted to purchase a good turntable, but I have no place for it and it's yet another diversionary rabbit hole I don't need. I ain't gonna call out the name vinyl around here.

Last week I was struggling to come up with enough new items to fill the post; this week I'm wrestling to pare down the list of topics. We've had some more concerning news about autochthonous tropical infectious diseases cropping up, but before I turn to that....

Is Covid Coming Out of the Doldrums?

Lots of headlines about this in the past week, some more hysterical than others. Staying alert, not panic, is the appropriate response.

First to wastewater. Looking at the past 6 months in Biobot, every US region is trending up, notwithstanding a slight drop in the purple midwest region.

Now look at the same graph spread out over a longer time:

So yes, we've had an upward blip recently, but nothing as dramatic as what accompanied serious clinical outbreaks in the past.

The other hype is about newer variants. Fortunately, we're still talking about omicron and primarily from the XBB subvariant group. I'll turn to the UK's nice graphs to highlight; results are similar but not identical to the US.

This Sankey diagram gives you an idea of the relatedness of strains:

The key question is how well the proposed autumn covid vaccine, derived from XBB.1.5, works against these newer variants. The answer is based mostly on conjecture at this time, we have no peer-reviewed hard data yet. The best guess is that it will not protect much against infection itself, nor will prior natural immunity. However, for the more important protection against severe disease, hospitalization, or death, it is likely to have an impact. Jennifer Abassi, a medical news reporter for JAMA, published a nice discussion. CDC and IDSA recently posted a brief explanation. Also in the news the past few days has been a newer variant, BA.2.86, now seen in a few countries sporadically including the US. It's much too early to know if this will become prominent.

CDC published updated data about monovalent and bivalent vaccination in the 6-month to 4- or 5-year-old age groups that showed good effectiveness in protection against urgent and emergency care visits. Also important to note is that these are relatively uncommon events in this age group, which is why you see different recommendations for vaccination in the US versus the UK for example. Going from the last section of Table 2 in the article, rates of these care visits from 12/24/22 to 6/17/23 were 4.4% in the unvaccinated group versus 0.9% in those who had received at least one bivalent vaccine dose. With a little arithmetic, the number needed to vaccinate at this level to prevent one additional ED/urgent care visit is about 30.

Reason to Avoid Proton Pump Inhibitors

French investigators published a cohort study linking use of PPIs in children to higher risk of serious infections. It included over 600,000 children receiving PPIs and a similar number as a control group not receiving PPIs, followed for a few years. The risks for serious infections as well as a number of categories of infection types were significantly increased. Most of the children had significant comorbidities. This association has been known in adults for a long while and is likely based on a variety of PPI effects including elevated gastric pH and alteration of the GI microbiome. That's not to say PPIs shouldn't be used in children, but there is a clear risk that should be explained to parents.

RSV Already in Florida

Florida is now seeing RSV infections in some jurisdictions. This isn't too surprising; Florida has a very different seasonal epidemiology than does most of the US:

It remains to be seen how RSV seasonality will stabilize in the post-pandemic/isolation era. A group in the Netherlands recently reported a switch to year-round transmission during the pandemic.

Along similar lines, a US study showed that ICU admissions for RSV consisted primarily of infants without risk factors; the study does have significant limitations. Findings may reflect the lack of partial RSV immunity conferred by prior RSV exposure of both mothers and infants.

It's still time to plan for use of monoclonal antibody and, if approved, maternal RSV vaccination. AAP and ACIP have a nice discussion available. Lots of logistical hurdles remain.

Autochthonous Malaria and Dengue

I posted about autochthonous malaria in Florida and Texas on July 2 and 9, and on autochthonous dengue fever in Arizona on 11/20/22. See the July 2 post for more about the definition of autochthonous infections.

Now we have a report of 11 autochthonous dengue cases in Florida. Closer to home, we've had a report of 1 case of autochthonous P. falciparum in a Maryland resident in the National Capital Area region. Falciparum malaria is significantly more dangerous than the vivax forms reported in Florida and Texas. Very little information was provided, but the letter does have links to good clinical information sites.

Autochthonous infections are tricky to diagnose given the lack of travel history to an endemic area. Climate change has expanded the geographic range of many insect vectors of disease. All clinicians should be aware of these diseases when evaluating febrile patients.

As a final note, my web wanderings about autochthony taught me something new about the term. Sadly, it has been used in a negative political (and racist) sense. An "autochthonous" flag protest disrupted a 2014 soccer match between Serbia and Albania.