Field Comparison of Removed Substrate Sampling and Emergence Traps for Estimating Culicoides Orbivirus Vectors in Northern Florida.

The larval ecology of Culicoides (Diptera: Ceratopogonidae) influences their spatial distributions and the pathogens they transmit. These features are of special concern for deer farmers in Florida where epizootic hemorrhagic disease virus (EHDV) is a major source of mortality in captive herds. Rarity of larval morphological expertise leads many researchers to study larval ecology by quantifying emergence, either with field emergence traps or removing substrate from the field for observation under laboratory conditions. We investigated the comparability of these methods in Florida seepages where two recently implicated EHDV vectors, Culicoides stellifer Coquillett and Culicoides venustus Hoffman, are common. We compared the abundance and composition of emerging Culicoides collected from emergence traps with removed substrate samples (soil plugs) at three seepages. Soil plugs were sampled adjacent to the emergence trap and from underneath the trap footprint, and then monitored under laboratory conditions for 11-13 wk to compare the methods and to assess the role of incubation period for removed substrate samples. Emergence traps and removed substrate sampling largely agreed on community compositions and trends within different seepages. However, comparatively large numbers of C. stellifer emerged later than expected and well into the incubation period with emergence still occurring after 13 wk (90 d). Removed substrate samples were more similar to emergence traps at shorter incubation times. The importance of time for the capture of Culicoides in removed substrate sampling was more pronounced than we anticipated and is important from both a methodological and biological perspective.

Diagnostic Accuracy of Suspected Appendicitis: A Comparative Analysis of Misdiagnosed Appendicitis in Children.

OBJECTIVE: When evaluating suspected appendicitis, limited data support quality benchmarks for negative appendectomy (NA); none exist for delayed diagnosis of appendicitis (DDA). The objectives of this study are the following: (1) to provide preliminary evidence supporting a quality benchmark for DDA and 2) to compare presenting features and diagnostic evaluations of children with NA and DDA with those with pathology-confirmed appendicitis (PCA) diagnosed during initial emergency department (ED) encounter. METHODS: Secondary analysis of data from a QI project designed to reduce the use computed tomography when evaluating suspected appendicitis using a case-control design. Patients undergoing appendectomy in an academic tertiary care children's hospital system between January 1, 2015, and December 31, 2016 (n = 1,189) were eligible for inclusion in this case-control study. Negative appendectomy was defined as no pathologic change or findings consistent with a different diagnosis. Delayed diagnosis of appendicitis was defined as patients undergoing appendectomy within 7 days of a prior ED visit for a related complaint. Controls of PCA (n = 150) were randomly selected from all cases undergoing appendectomy. RESULTS: There were 42 NA (3.5%) and 31 DDA (2.6%). Cases of PCA and NA exhibited similar histories, examination findings, and underwent comparable diagnostic evaluations. Cases of PCA more frequently demonstrated a white blood cell count greater than 10 × 103/µL (85% vs 67%; P = 0.01), a left-shift (77% vs 45%; P < 0.001), and an ultrasound interpretation with high probability for appendicitis (73% vs 54%; P = 0.03). Numerous significant differences in history, examination findings, and diagnostic tests performed existed between cases of PCA and DDA. CONCLUSIONS: Children with PCA and NA present similarly and undergo comparable evaluations resulting in appendectomy. A 3% to 4% NA rate may be unavoidable given these similarities. Presenting features in DDA significantly differ from those of PCA. An irreducible proportion of appendicitis diagnoses may be delayed.

Host Bloodmeal Source Has No Significant Effect on the Fecundity and Subsequent Larval Development Traits of the Progeny in Culicoides furens Poey (Diptera: Ceratopogonidae).

Culicoides Latreille species (Diptera: Ceratopogonidae) are insects of significant medical and veterinary importance worldwide because their bites can cause major annoyance, allergic reactions, and/or pathogen transmission to vertebrates, including humans. In this study, we examined the effect of host bloodmeal source on the fecundity and subsequent larval development traits of the progeny of Culicoides furens Poey, a nuisance species in coastal Florida. Field-collected females were fed on two different classes of hosts: birds (chicken) or mammals (human). Fecundity outcomes of the females and larval developmental traits of the progeny were recorded and compared between the two groups. The percentage of females that developed eggs, percentage of gravid females that deposited eggs, number of eggs produced per female, number of eggs deposited per female, egg hatch rates, larval survival rates, time to pupation, pupal sex-ratios, and adult eclosion rates were not significantly different between the two groups. Our results demonstrate that the host bloodmeal source has no significant effect on the fecundity and subsequent larval developmental life-history traits of the progeny in C. furens. Previous studies reported C. furens to be a generalist feeder that shows no host preference for birds or mammals. Collectively, these findings suggest that C. furens is well adapted, not just behaviorally, but also physiologically to efficiently utilize blood meals from avian and mammalian hosts, a quality that offers a major evolutionary advantage to the success of this midge species as a generalist feeder.