Tag: foodborne illness

Ever read Beowulf? Me neither. Nor do I plan to ever read this epic poem consisting of 3182 lines of alliterative verse. Recently I did read Grendel by John Gardner. Grendel is the monster who was killed by Beowulf in the famous poem. Gardner's book is told entirely from Grendel's perspective, very different from how Beowulf and the other humans saw things of course.

Malaria Season

Practicing in the Washington, DC, area for almost 40 years meant that I had a steady diet of malaria. Our "malaria season" was towards the end of summer when vacationing families returned home after visiting relatives in malaria-endemic countries. This seasonality abated a bit during the pandemic when international travel was scarce, then came back with a vengeance. Now, however, autochthonous malaria has been reported in Florida and Texas.

Autochthonous, from the Greek autokhthon meaning "sprung from the land itself," in this instance refers to malaria acquired without visiting a malaria-endemic country. I didn't mention the initial CDC report a couple weeks ago, but now that a second state is involved and CDC issued a health alert advisory, I'll attempt to summarize what's happening.

We still have virtually no clinical details about any of the 5 cases, but CDC implied they are all due to Plasmodium vivax which is not as severe/deadly as P. falciparum. Autochthonous malaria in the US was common in the old days, but since effective mosquito control programs in the 1950s it has been scarce. Prior to the current reports, we hadn't seen autochthonous malaria since 2003. High risk areas in the US are those that have high population density, plenty of Anopheles mosquitoes (including favorable conditions for their reproduction), and a source of people who have recently traveled from malaria-endemic areas. So, it's not surprising that Florida and Texas are points of origin now.

Speaking of mosquitoes, climate change has greatly increased the range of various insect vectors of disease; for example, Lyme disease risk has expanded geographically in recent years as deer ticks broaden their range. Anopheles mosquitoes are present in virtually the entire US.

For frontline providers, malaria shouldn't be the first thing to suspect in a child with fever in the US, but recognize that in cases of prolonged fever it is a consideration even without a history of international travel. Look at the CDC's malaria website for more details, and read this article if you want to see a longer discussion of (prepandemic) autochthonous malaria.

Foodborne Disease is Back

Another sign that the pandemic is lifting is this CDC report of 2022 data. Certain foodborne illnesses such as Shiga toxin-producing Escherichia coli, Yersinia, Vibrio, and Cyclospora infections increased compared to 2016–2018 data; Campylobacter, Salmonella, Shigella, and Listeria incidences didn't change much. Although they didn't show the data in this report, foodborne diseases decreased in the 2020-2021 time period.

I was a bit disappointed that, although the report did mention increased use of culture-independent diagnostic testing rather than culture, it did not mention the fact that the highly sensitive CIDT methods can be more prone to false positives. This makes it difficult to compare trends across time periods.

Ideally one would perform a backup culture test for bacterial pathogens particularly to detect antimicrobial resistance; CIDT can not test for this.

Can We Shorten Treatment Duration for Pediatric Urinary Tract Infection?

The short answer is yes, but the more difficult question is how to decide which patients are appropriate for shortened therapy. Even this randomized controlled trial couldn't answer that question. The study compared 5 versus 10 days of therapy for UTI in children 2 months to 10 years of age. Children who showed clinical improvement at 5 days treatment were then randomized to another 5 days of antibiotic versus placebo. Failure rate in the 10-day treatment group was 0.6% versus 4.2% in the 5-day group.

Ultimately I think the details of study design doomed this trial to leave this question mostly unanswered. In particular the duration of followup after stopping antibiotic was too short for the 10-day group (which would have skewed results to a falsely low failure rate). Fundamentally the problem with UTI treatment in children is trying to determine which children have pyelonephritis versus just cystitis, much more difficult in children than in adults. Pyelonephritis likely requires more than 5 days of treatment.

This study definitely adds to our understanding of pediatric UTI but I don't think is immediately transferrable to clinical practice. The accompanying editorial offers some ideas in this regard.

'Demic Doldrums

We continue to enjoy relief from covid from the standpoint of no evidence of major surges around the world, just continued pockets of upswings in disease activity (tempered by the knowledge that we aren't tracking it very well now). Of course, the number of total cases in this WHO graph, as of June 28, is pretty depressing overall.

According to WHO, confirmed covid deaths now number 6,947,192.

Blood Group and Covid

I have blood group A positive. Should I be worried? It's been known for a while that individuals with type A blood have a slightly higher risk of SARS-CoV-2 infection, and this recent article lends some credence to these observations by supplying a biologic explanation. The A blood group antigen is very attractive to the receptor binding domain of the virus, including omicron variants. But no, I'm not concerned. The increase in infection risk attributable to blood group is very small, paling in comparison to other risk factors.

Whatever Happened to Wastewater Monitoring?

In the US, wastewater monitoring for viruses like SARS-CoV-2 has great potential but is ineffective because it involves voluntary reporting by states. Most people in the US live in areas that don't monitor wastewater. Our northern neighbors in Canada, specifically Peel, Ontario, provide evidence that wastewater monitoring truly can be an early warning for increased infections. Investigators reported that wastewater levels predicted very reliably 1 day before the rise in infections and 4 days before a rise in hospitalizations during the omicron period of November 2021 to June 2022. At this point I'm not sure if the US has the resources to implement wastewater virus monitoring on a larger scale.

Better Evidence for MIS-C Treatment

The multi-system inflammatory syndrome in children is still difficult to diagnose precisely. Thankfully MIS-C seems less common in today's covid era with omicron dominance and high levels of antibody in the population. Now we have some better guidance for immunomodulatory therapy for MIS-C. This meta-analysis suggests that the combination of intravenous immunoglobulin plus glucocorticoid therapy improved cardiovascular dysfunction better than either agent alone. The study was very well done but had to rely heavily on nonrandomized cohort studies which introduces a great degree of bias in the results. We missed a chance by not conducting large RCTs of MIS-C treatment early in the pandemic.

Understanding Grendel

I needed to consult Wikipedia and other Cliff Notes-like versions of Beowulf to understand Gardner's book. As with everything I read, I think about what, if anything, might apply to me. With Grendel and Beowulf it was relatively easy. When faced with dramatically different perspectives, say for example pandemic deniers or anti-vaxxers (Grendel) versus traditional science and medicine (Beowulf), it's a good idea to try to see things from the opposing perspective. If one can do this without resorting to raised voices or worse, it's possible to have a meaningful dialog and even occasionally change minds, even my own! Next time you see me, look for Grendel perched on my shoulder. For those less prone to wild fantasies I recognize this is quite a stretch, but regular readers are accustomed to my tangents.