wastewater tracking – Page 3 – Pediatric Infection Connection

Meh

Bud WiedermannJune 30, 2024June 30, 2024Leave a comment

I had expected last week's ACIP meeting to include more presentations and discussions about which covid strain to include in our fall vaccine. I viewed only a small portion of the meeting live (darn those pesky patient care issues!), so I probably missed any brief mention of strains; the slides themselves didn't address strain selection, other than to go with the FDA's statement for use of JN.1 lineage with preference for KP.2 if possible. I still found some interesting details about covid and nirsevimab and will share those with you. Perhaps meh is a bit of a harsh judgement, but I love the word.

In the meantime, thankfully still not much going on in the pediatric infectious diseases world this summer.

Love That New Technology

The CRISPR technology has been in the news for a long time. In case you had forgotten, like I did, it stands for Clustered Regularly Interspaced Short Palindromic Repeats and is now reported to have high sensitivity and specificity for detecting antiviral drug resistance and influenza subtype rapidly enough to be used as a point-of-need assay. The study itself requires journal subscription (thank you, GWU faculty status) to read in full. Investigators studied influenza isolates from the 2020-21 season looking primarily at AH1N1 and AH3N2 strains. The report is highly technical, beyond my ability to critique the laboratory methods, but the take-home message is important: if such a method is scalable (e.g. cheap enough) to employ across the world, including in resource-poor communities, it would be a boon to early warnings of resistant and/or new flu strains. I'm keeping my fingers crossed.

I must applaud scientists in this realm for their acronym constructions: in addition to CRISPR and others, they also used DETECTR (DNA endonuclease-targeted CRISPR trans reporter) and SHERLOCK (Specific High-sensitivity Enzymatic Reporter unLOCKing) assays. Elementary, my dear Watson. (And, that phrase never appeared in any of Arthur Conan Doyle's writings!)

Dengue HAN

Perfect timing after my mention of dengue last week, the CDC issued a Health Alert Network warning about dengue in the US. According to the Pan American Health Organization, early signs are that cases in the Americas this year will exceed last year's numbers, a year that was already much higher than previous years. Here's an example from the report of what's going on in the Caribbean subregion:

Puerto Rico is under a healthcare emergency because of dengue, and we will certainly have cases of autochthonous (acquired in the US without travel to an endemic area) transmission in the mainland US again this year, primarily in Florida and other southern states. The HAN is worth reading.

This would be a good time to review clinical presentations of dengue and be prepared to investigate/obtain consultation for suspected cases.

Pustules and Vesicles in Afebrile Infants <60 Days of Age

Pediatrics had a nice retrospective review of 183 infants from 6 academic hospital-based pediatric dermatology practices. It's open access and has a nice suggested management algorithm.

Note the first branch in the algorithm details key features to decide whether HSV evaluation and treatment is recommended.

ACIP Meeting Highlights

The regular meeting was spread over 3 days last week. Slides are posted, and I picked out a few that contained interesting new information.

First, even with all the problems of supply chain and late administration, nirsevimab appears to have been incredibly effective in preventing RSV hospitalizations and healthcare visits.

Yes, that's about 98% effectiveness in preventing hospitalization, with very narrow confidence intervals. When this slide was shown it elicited a round of applause from the committee members. This is truly remarkable. Similar results were seen using a different RSV surveillance method. Both the above and below slides are from the Payne presentation on June 28.

It appears we'll have better availability of nirsevimab for the next RSV season, so please prepare for that. I find myself fantasizing of some future day when new pediatric trainees won't see hordes of infants hospitalized with RSV bronchiolitis, with worried parents at the bedside.

Second, although I mentioned I didn't see any new data/discussion about strain selection, the covid vaccine discussion had useful updates about epidemiology and risk factors, mainly from the Haver presentation on June 27.

About half of children hospitalized for covid had no underlying risk factors; we already knew that, but here's a more detailed breakdown. Note that these numbers are for the past year, at time when virtually all US children had some prior antibody from infection and/or vaccine.

Here is the vaccination status, including the low numbers who received the 2023-24 version, of the hospitalized children:

One BIG disappointment for me with the presentations: there was no mention of a control group - i.e. what are the rates of underlying medical conditions and 2023-24 vaccine status in the pediatric population as a whole? Adjusting for rates in the general population would provide a better estimate of the relative contributions of risk factors and vaccination to more serious outcomes and give us a better handle on the magnitude of benefit of vaccination, for example. Still, nothing has changed; for the individual child, covid vaccination is better than not being vaccinated, even factoring in the low rates of serious outcomes and adverse vaccine events in children.

The 2023-24 vaccine was highly effective against emergency department and urgent care visits in all age groups, though waning of protection over time was seen. Lack of enough events of hospitalized children precluded reliable estimates of VE against pediatric hospitalizations. (Link-Gelles presentation June 27.)

Bird Flu

Exciting (to me) news that CDC is collaborating with the Michigan health officials to carry out a seroprevalence study for H5N1 infection in Michigan dairy workers. This should produce much better information about asymptomatic and mild infection in humans and possibly lead to more clues about transmission.

Covid Uptick?

Still a question, but positive test percentages are increasing, albeit at a low level and predominantly driven by western states.

Wastewater variant detection is lacking across the country, see all the block dots (no sequencing data) below, but you can magnify your area of the country and find a few sites with enough data to determine predominant covid strain.

For example, in my neck of the woods most of the sites have no sequencing data. Of the 2 that did, one showed a predominance of KP.2 and the other LB.1. Nationally, KP.3 is starting to exceed KP.2. Again, we're still at low numbers.

A Tip of the Hat to "The Simpsons."

I knew that "meh" might have been adopted from a Yiddish term meaning so-so or unimpressive, but it looks like a 1994 episode of the TV series The Simpsons, featuring ultraconservative Sideshow Bob, popularized the term. Lisa Simpson was investigating voter fraud as the reason Sideshow Bob was elected as Springfield's mayor, and the "meh" word was uttered by a Hall of Records bureaucrat when Lisa expressed disbelief that he would give her the entire mayoral voting records that should have been kept secret. (Thie episode is available only with subscription, but I verified the quote at about 15:30 time in the recording.)

Voter fraud 30 years ago?

Summer Doldrums

Bud WiedermannJune 2, 2024June 2, 2024Leave a comment

Yes, summer doesn't officially begin for almost another 3 weeks (June 20, 4:51 PM EDT is summer solstice where I am), but it's a relatively stagnant time for infectious diseases now. It's sort of nice to view the maps and graphs right now. Just bask in the green of influenza-like activity:

I've mentioned recently that covid and other tracking systems are now ramped down in many jurisdictions, so we're mostly back to crystal ball predictions. Wastewater data, now including influenza in addition to SARS-CoV-2 and mpox, can be helpful in anticipating disease surges, but as you can see in the example below for influenza A, we have almost no data for most of the country - the gray dots aren't reporting.

And, speaking of flu ....

Avian Flu

If you aren't in close contact with fowl (includes backyard poultry aficionados) or cattle, you don't have much to worry about influenza A H5N1. Still, we did see our third human case in the US last week, this time from another dairy farm worker in Michigan who was exposed to infected cows. Symptoms seemed mild but were slightly different from the 2 previous cases that only had conjunctivitis. This third individual complained of cough and eye discomfort with watery discharge and was afebrile. He was treated with oseltamivir.

Front line clinicians assessing anyone for respiratory illness, including conjunctivitis, should ask about close contact with sick or dead animals, particularly wild or domestic birds, wild mammals, and domesticated animals including cows.

The World Organisation for Animal Health now lists 26 different groups of animals confirmed positive for avian influenza A H5N1 across the US:

Wild animals: coyote, Virginia opossum, feral cat, gray seal, bobcat, Mephitidae unidentified (includes skunks and stink badgers), striped skunk, American mink, tiger (where was a wild tiger in the US?), harbor seal, northern raccoon, puma, bottlenose dolphin, American black bear, brown bear, polar bear, red fox, Amur leopard (again, in the wild in the US?), fisher, American marten, and Abert's squirrel

Domestic animals: Camelidae (alpacas in this instance), cat, goat, cow

Also, ingestion of unpasteurized dairy products is a risk factor for mammals, likely including humans. So far it isn't entirely clear whether ingestion of raw beef is a risk factor, but good to ask your patients about. Anyone with a risk factor should undergo influenza testing and, if positive especially this time of year get help from your local health department.

If nothing else, I learned about a few new (to me) animals from investigating the WOAH list. Thank goodness for Wikipedia.

Looking Ahead

The postponed FDA VRBPAC meeting to advise on composition of the next covid vaccine is still scheduled for June 5. Pertinent meeting materials usually appear on the website a day or so before the meeting, but nothing so far to tip FDA's hand on which variant(s) will be included in the next iteration.

In the meantime, enjoy the doldrums!

The Future is Bright

Bud WiedermannDecember 31, 2023December 31, 2023Leave a comment

2023 wasn't exactly the best of years, but at least we didn't slip back into pandemic circumstances. I fear we will see some "old" infections become new again in 2024. General immunization rates are falling; even before that, we saw plenty of pertussis and even some tetanus, but now we may become reacquainted with measles and varicella, among other vaccine-preventable diseases. Time for some of those younger pediatric healthcare providers who have never seen children with these infections to hit the textbooks again - how's that for a New Year's resolution!

Still, we have lots of reasons to hope for improvements in 2024. Maybe AI won't take over the world but instead will help us practice more effectively.

Short Course Therapy for Febrile UTI in Children

The literature just got a bit muddier with regard to treatment duration for pediatric UTI with a new study from Italy. Investigators in 8 pediatric emergency departments randomized 142 children ages 3 months to 5 years with fever and UTI to receive either 5 or 10 days of oral amoxicillin/clavulanate. The study wasn't blinded, and the randomization occurred on day 4 of therapy when urine culture results were available. UTI was defined as a single organism growing at >100,000 cfu/ml in clean catch urine or > 10,000 cfu/ml in catheterized urine, and subjects were followed for 30 days after completion of antibiotic. After a planned interim analysis the study was stopped early due to finding of noninferiority of the short course therapy.

As you can see, the short course group had numerically lower rates of UTI recurrences during this time period. However, this study's results contradict another study, with a somewhat more reliable study design and definitions, that showed short course therapy to be inferior. I reviewed this earlier study in my July 2, 2023 post. The editorial accompanying the new study is an excellent discussion of weighing the relative merits of the 2 studies. Suffice to say, the jury is still out, and I would stick with 10 days of therapy for febrile UTI in most children.

More Evidence for Using Nirsevimab to Ameliorate Bad Outcomes from RSV

Investigators in 3 European countries conducted a randomized trial of the long-acting monoclonal antibody nirsevimab showing benefits in preventing RSV-associated hospitalization, especially in younger infants. Note that subjects for this study were not eligible for receiving nirsevimab currently in these countries; they were all healthy infants less than 12 months of age, born at > 29 weeks gestation, who were entering their first RSV season.

This was a pragmatic trial, meaning that it was carried out under more "real-world" practice situations rather than within the strict confines of "explanatory" trials used with most therapeutic research studies. It lends more evidence to benefits of nirsevimab for young children.

WRIS (Winter Respiratory Illness Season)

Most pediatric healthcare providers across the country know that we are in the midst of a busy WRIS. This also is a time when data are least reliable due to the extended holiday season - reporting lags a bit, so trends seen now are more likely to be revised in the next few weeks. Still, it's worth a look.

Researchers in Stockholm, Sweden, looked at pediatric hospitalization rates for the 3 "tripledemic" viruses during the period 8/1/21 to 9/15/22 and found that rates were higher for RSV than for omicron covid (the time period was entirely omicron in Sweden) or influenza; note especially the numbers for younger children. I'll be interested to see if this pattern is seen in the US this winter.

CDC has a new (to me) section charting epidemic growth status for covid and influenza, i.e. it depicts, by locale, the growth rates but not the absolute numbers of these pathogens. Another interesting tidbit.

Along the same lines is a monthly crystal ball page from CDC, a bit of sticking their necks out to predict what's in our future for respiratory illnesses. The last report is from November 29:

Lots of uncertainties here, but I appreciate the attempt.

Now for a look at our usual sources for data.

FLUVIEW

Circulating strains are still well-matched to this year's vaccine.

Covid wastewater is increasing, and several healthcare facilities across the country have reinstituted masking and other mitigation practices due to high rates in their communities.

RSV is the one "tripledemic" component that seems to be decreasing in most areas.

So, WRIS this year seems to be a double-whammy rather than a tripledemic, still more than enough to strain healthcare resources. I can only dream how much better people's health would be with widespread vaccine acceptance.

We're Still Safe from the AI Bots

I tried to use an AI program, Microsoft Copilot's Suno, to compose a song about this blog. Specifically, I asked it to create a song about the Pediatric Infection Connection blog using the blues genre. Here's what I got.

Their link doesn't exist, nor is there a pediatric infectious disease specialist Dr. Sarah Jones certified by the American Board of Pediatrics. I did find a Sarah Jones infectious diseases pharmacist at Boston Children's Hospital, but she doesn't appear to have a blog and I don't know if she has children.

I think, for the next year, we'll still be able to keep AI from fooling all of us.

Have a Happy and Safe New Year!

Happy Holidays

Bud WiedermannDecember 24, 2023December 25, 2023Leave a comment

'Tis the season, both for holidays as well as for infectious diseases. Last week's publications featured a wide variety of articles of interest; I'll try to keep it short. As much as I focus on infectious diseases, now is prime time to spend with friends and family.

Multiplex Stool Testing in Gastroenteritis

Children with acute gastroenteritis presenting to one of five different children's hospitals' on site urgent care or emergency departments submitted stool specimens for multiplex PCR testing. The study plan was interesting. For the first approximately 100 subjects, stools were tested regardless of whether the test was ordered by their clinicians (after informed consent from parents, of course). Then there was an intervention period where clinicians received education about the test performance characteristics and clinical management of the infections that the PCR could detect. Regardless of whether or not you look at the article, you may find these educational materials of use in your practice. I did note that the study was funded by NIH but also by the company that manufactures the PCR tests, plus most of the authors were employees of or received outside funding from the manufacturer. This is important because of high risk of implicit bias affecting the report.

"Clinically relevant" pathogen detection rate rose from 2% in the pre-intervention period to 15% after intervention, and return visits decreased after the intervention. There was a trend towards appropriate treatment given post intervention, though not statistically significant.

Indiscriminate use of multiplex PCR assays in acute gastroenteritis has a great potential to cause unnecessary treatment, especially for C. difficile in young children where the carrier rate is so high. It's not surprising that targeted education would be helpful. Also, because the test cannot determine antibiotic resistance patterns, laboratories would be advised to provide reflex susceptibility testing for selected pathogens that might require antibiotic treatment and also have significant resistance rates.

Covid Morsels

A few tinsel-tinged tidbits about covid caught my eye this week. First of all, CDC had a couple reports both suggesting that rebound after Paxlovid treatment was not clinically significant and no different than after placebo treatment. The more substantial report was a closer look at viral RNA shedding from 2 randomized placebo-controlled trials, from both early and later in the pandemic, involving adults only. Rebound rates were about the same in the treatment and placebo groups, both around 6-8%.

We've seen a wide variety of reports about rebound after Paxlovid, but clearly the weight of evidence suggests that viral rebound after treatment does not result in severe disease and that rebound rates likely are not clinically significant from rebound rates in untreated patients. Rebound concerns should not be a factor in decision to treat with Paxlovid.

Also this past week, the WHO stated that antigen composition for covid vaccines should remain the same for now, i.e. based on the XBB lineage of omicron that continues to represent the vast majority of circulating strains worldwide. The BA.2.86 descendents, including JN.1, are rising but with no big concerns yet about greater virulence or significant lack of protection from the XBB.1.5 monovalent vaccines now in use. As I've stated in previous posts, I've not been commenting on emergence of new subvariants unless/until they are shown to have clinical relevance; so far JN.1 does not meet that threshold.

A multidisciplinary panel of infectious diseases, microbiology, and epidemiology experts published an exhaustive guideline for use of molecular diagnostic testing for covid 19. I struggled with how to summarize all the information, suffice to say that the methodology for guideline development and the evidence behind the recommendations are stated clearly. I'll just present the bottom line summary, but please dig into the article for details if you are interested. Note that, if you haven't already, it would be helpful to identify sites near you where nucleic acid amplification testing (NAAT) with quick turnaround of results is available.

A multinational group of investigators summarized reports of laboratory-acquired infections (LAIs) and accidental pathogen escape from laboratory settings (APELS) between 2000 and 2021. Sixteen APELS were reported and involved anthrax, SARS-CoV (the original), and polio (3 each); Brucella spp and foot and mouth disease virus (2 each); and single episodes of variola virus, Burkholderia pseudomallei, and influenza H5N1 virus escape. LAIs were much more common with a total of 94 reports involving over 300 infected individuals. LAIs more commonly involved Salmonella spp, Brucella spp, and vaccinia virus. Although the study doesn't answer the question of SARS-CoV-2 origin, it certainly can inform measures to prevent lab accidents in the future.

Winter Respiratory Illness Season

Cumulatively our winter respiratory illnesses are increasing. I'm interested to see what the holiday school breaks and travel will do to the epidemic curves. I've been trying very hard to streamline finding current data that also is broken down by location so I can see my own local trends; unfortunately I don't find a single best one-stop shopping site for this purpose.

For general virus surveillance besides covid and influenza, look at the CDC's National Respiratory and Enteric Virus Surveillance System (NREVSS). You can then click on links to 4 groups of respiratory viruses (including RSV) as well as to 2 enteric viruses, rotavirus and norovirus. Here's an example of the South Region's (which includes my area of DC, MD, and VA) most recent RSV detection activity:

The CDC's COVID Data Tracker provides an extensive view of various indicators of disease activity, though not of wastewater which is still available at the National Wastewater Surveillance System (see below). Here's a quick view of the Data Tracker's most recent headline:

Wastewater covid continues to rise nationally.

Last but not least, our old friend influenza continues to spread across the country:

Have Your Cake and Eat It Too

I did say at the start this was a time to balance my obsession with all things infectious and my desire to have fun times with family and friends during the holidays, and I'll mention one way to (almost) do both. The annual Christmas issue of the BMJ was released. It always contains a few tongue-in-cheek articles - real research but performed for silly premises. The only infectious diseases-related article this time around was a study of bacterial contamination of hospital coffee machines. Surprisingly to me, the level of true pathogens they found was pretty low. I'm helping with some baking today, fans of the Great British Bake Off will enjoy this article.

However you spend the holidays, please take time to enjoy friends and family.

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.

Tag: wastewater tracking

Meh