Vesicular Stomatitis Virus Detected in Biting Midges and Black Flies during the 2023 Outbreak in Southern California.

Vesicular stomatitis (VS) is a viral disease that affects horses, cattle, and swine that is transmitted by direct contact and hematophagous insects. In 2023, a multi-state outbreak of vesicular stomatitis New Jersey virus (VSNJV) occurred in California, Nevada, and Texas, infecting horses, cattle, and rhinoceros. To identify possible insect vectors, we conducted insect surveillance at various locations in San Diego County, CA, including at a wildlife park.

Wastewater sequencing uncovers early, cryptic SARS-CoV-2 variant transmission.

As SARS-CoV-2 continues to spread and evolve, detecting emerging variants early is critical for public health interventions. Inferring lineage prevalence by clinical testing is infeasible at scale, especially in areas with limited resources, participation, or testing/sequencing capacity, which can also introduce biases. SARS-CoV-2 RNA concentration in wastewater successfully tracks regional infection dynamics and provides less biased abundance estimates than clinical testing.

An amplicon-based sequencing framework for accurately measuring intrahost virus diversity using PrimalSeq and iVar.

How viruses evolve within hosts can dictate infection outcomes; however, reconstructing this process is challenging. We evaluate our multiplexed amplicon approach, PrimalSeq, to demonstrate how virus concentration, sequencing coverage, primer mismatches, and replicates influence the accuracy of measuring intrahost virus diversity. We develop an experimental protocol and computational tool, iVar, for using PrimalSeq to measure virus diversity using Illumina and compare the results to Oxford Nanopore sequencing.

Endosymbiont interference and microbial diversity of the Pacific coast tick, , in San Diego County, California.

The Pacific coast tick, Marx, is found throughout California and can harbor agents that cause human diseases such as anaplasmosis, ehrlichiosis, tularemia, Rocky Mountain spotted fever and rickettsiosis 364D. Previous studies have demonstrated that nonpathogenic endosymbiotic bacteria can interfere with co-infections in other tick species. We hypothesized that within ticks, interference may exist between different nonpathogenic endosymbiotic or nonendosymbiotic bacteria and Spotted Fever group Rickettsia (SFGR).

Rapid bilateral intraocular cocktail sampling method for West Nile virus detection in dead corvids.

Corvids can be a sensitive indicator for West Nile virus (WNV) prevalence and are a component of many WNV surveillance programs. An improved sampling procedure using a bilateral intraocular cocktail (BIC) was developed for testing corvid carcasses for WNV. This new procedure was substantially faster than harvesting internal organs, required less specialized equipment and training, and yielded excellent diagnostic sensitivity.

Local veterinary diagnostic laboratory, a model for the one health initiative.

The San Diego County Animal Disease Diagnostic Laboratory (ADDL) is unique in its emphasis on protecting both human and animal health in San Diego County, and its use of interagency and community collaboration to create strong, effective public health programs. This article describes the ADDL core programs of avian and vector-borne disease surveillance, rabies testing, and animal abuse investigations and uses selected case studies to illustrate the need for a local veterinary diagnostic laboratory to safeguard the health of humans and animals. The ADDL serves as a role model for other local communities to develop vital public health partnerships to ensure a healthier community.

Thymic cystic degeneration, pseudoepitheliomatous hyperplasia, and hemorrhage in a dog with brodifacoum toxicosis.

Thymic cysts with pseudoepitheliomatous hyperplasia are described in a 7-month-old female American Eskimo Dog that died of complications from brodifacoum poisoning. Grossly, there was hemothorax with marked cranial mediastinal hemorrhage. Histologically, thymic lobules were expanded and distorted by irregular cysts, lined by single to multiple layers of plump to slightly attenuated polygonal squamous epithelial cells supported by a basement membrane (pseudoepitheliomatous hyperplasia).

Discrimination between Francisella tularensis and Francisella-like endosymbionts when screening ticks by PCR.

The presence of Francisella-like endosymbionts in tick species known to transmit tularemia poses a potential diagnostic problem for laboratories that screen tick samples by PCR for Francisella tularensis. Tick samples initially considered positive for F. tularensis based on standard 16S rRNA gene PCR were found to be positive only for Francisella-like endosymbionts using a multitarget F.

Equine placental teratoma.

The placenta from a 300-day-gestational age, female, Arabian equine fetus was examined. Multifocal to coalescing, 0.5- to 4-cm-diameter, white, smooth nodules covered 50% of the placenta.

Genomic diversity of Bartonella henselae isolates from domestic cats from Japan, the USA and France by pulsed-field gel electrophoresis.

The genomic DNA diversity of 27 Bartonella henselae and three B. clarridgeiae isolates from 18 domestic cats from Japan, the USA and France was investigated by pulsed-field gel electrophoresis (PFGE) with NotI, AscI and SmaI restriction enzymes. A great diversity of genomic patterns was found for all B.