Angiostrongylus cantonensis Infection in Brown Rats (Rattus norvegicus), Atlanta, Georgia, USA, 2019-2022.

Rat lungworm (Angiostrongylus cantonensis), a zoonotic parasite invasive to the United States, causes eosinophilic meningoencephalitis. A. cantonensis harbors in rat reservoir hosts and is transmitted through gastropods and other paratenic hosts. We discuss the public health relevance of autochthonous A. cantonensis cases in brown rats (Rattus norvegicus) in Atlanta, Georgia, USA.

Reproductive tract neoplasia in adult female Asian elephants (Elephas maximus).

Recent reports have highlighted a lower-than-expected prevalence of neoplasia in elephants and suggested mechanisms for cancer resistance. But despite infrequent reports in the literature, uterine neoplasia is common in managed Asian elephants (Elephas maximus). This study is an archival review of reproductive tract neoplasia in 80 adult female Asian elephant mortalities in managed care facilities in the United States from 1988 to 2019. Neoplasms occurred in 64/80 (80%) of cases. Most were in the uterus (63/64; 98%) with only a single case of ovarian neoplasia. Myometrial leiomyomas were present in 57/63 (90%) cases with uterine neoplasia. Uterine adenocarcinoma was present in 8/63 (13%) cases. Remaining cases included endometrial adenoma (2), focal carcinoma in situ in endometrial polyps (1), anaplastic carcinoma (1), endometrial hemangioma (1), primitive neuroectodermal tumor (PNET; 1), and angiosarcoma (1). One case with uterine adenocarcinoma had a separate pelvic mass histologically characterized as an anaplastic sarcoma. Distant metastases were documented in 5/8 (63%) cases of uterine adenocarcinoma, and in the uterine anaplastic carcinoma, PNET, and angiosarcoma. Four uterine adenocarcinomas and one carcinoma in situ were examined immunohistochemically for pan-cytokeratin, vimentin, and estrogen receptor. In all, neoplastic cells were pan-cytokeratin positive and vimentin negative, and in 2 cases were immunoreactive for estrogen receptor. Results show that female reproductive tract neoplasia, particularly of the uterus, is common in Asian elephants and is not limited to leiomyomas. Importantly, uterine neoplasms have the potential to impact fecundity and may represent obstacles to conservation in managed care.

Landscape disturbance impacts on Attalea butyracea palm distribution in central Panama.

BACKGROUND: Increased Attalea butyracea palm propagation, notable for its role as key habitat for the primary Chagas disease vector in Panama, has been linked to landscape disturbance in single-palm observations in this region. Close proximity of these palms to human dwellings is proposed to increase risk of Chagas disease transmission from sylvatic transmission cycles to domestic transmission involving human populations. This study examines the relationship between landscape disturbance and mature A. butyracea spatial distribution, density, and proximity to human populations and vector and reservoir species' movement corridors at a regional scale in a 300 km2 heterogeneous tropical landscape in central Panama. METHODS: We remotely identified the locations of over 50,000 mature A. butyracea palms using high-resolution WorldView2 satellite imagery. A local Getis-Ord Gi* spatial analysis identified significant clusters of aggregated palms. Associations between palm and cluster abundance and a landscape disturbance gradient, derived from official Panama land cover data, were tested using Chi-square tests for Homogeneity and Z-test for proportions. Kruskall-Wallis non-parametric analysis of variance tests were run to assess whether palm cluster area varied by disturbance level, or whether disturbance was associated with proximity of palms and palm clusters to susceptible populations or vector movement corridors. RESULTS: Our findings indicate a regional relationship between landscape disturbance and A. butyracea occurrence. We observe a significant increase in both individual and clustered A. butyracea in secondary forest, but a reduction of palms in agricultural settings. We do not detect evidence of any reduction in abundance of palms in residential settings. The majority of residential and commercial buildings in our study area are within vector flight distance of potential vector habitat in palm crowns. CONCLUSIONS: We observe probable anthropogenic elimination of A. butyracea palms in agricultural, but not residential, settings. Even in heavily deforested regions, significant concentrations of mature palms remain in close proximity to human establishments.

Pathogen spillover during land conversion.

Pathogen spillover from wildlife to domestic animals and humans, and the reverse, has caused significant epidemics and pandemics worldwide. Although pathogen emergence has been linked to anthropogenic land conversion, a general framework to disentangle underlying processes is lacking. We develop a multi-host model for pathogen transmission between species inhabiting intact and converted habitat. Interspecies contacts and host populations vary with the proportion of land converted; enabling us to quantify infection risk across a changing landscape. In a range of scenarios, the highest spillover risk occurs at intermediate levels of habitat loss, whereas the largest, but rarest, epidemics occur at extremes of land conversion. This framework provides insights into the mechanisms driving disease emergence and spillover during land conversion. The finding that the risk of spillover is highest at intermediate levels of habitat loss provides important guidance for conservation and public health policy.

Prevalence, Genotype Richness, and Coinfection Patterns of Hemotropic Mycoplasmas in Raccoons (Procyon lotor) on Environmentally Protected and Urbanized Barrier Islands.

Raccoons (Procyon lotor) are successful urban adapters and hosts to a number of zoonotic and nonzoonotic pathogens, yet little is known about their hemoplasma infections and how prevalence varies across habitat types. This study identifies hemotropic Mycoplasma species infection in raccoons from urban and undisturbed habitats and compares hemoplasma infection in sympatric urban cats (Felis catus) from the same geographic region. We collected blood from raccoons (n = 95) on an urban coastal island (n = 37) and an undisturbed coastal island (n = 58) and from sympatric urban cats (n = 39) in Georgia, USA. Based on 16S rRNA gene amplification, 62.1% (59/95) of raccoons and 17.9% (7/39) of feral cats were positive for hemoplasma. There was a greater percentage of hemoplasma-infected raccoons on the undisturbed island (79.3% [46/58]) than on the urban island (35.1% [13/37]; χ2 = 16.9, df = 1, P = 0.00004). Sequencing of the full-length 16S rRNA gene amplicons revealed six hemoplasma genotypes in raccoons, including five novel genotypes that were distinct from three known hemoplasma species identified in the sympatric cats. In addition, the hemoplasma genotypes detected in raccoons were not identified in sympatric cats or vice versa. Although all six hemoplasma genotypes were found in raccoons from urban and undisturbed islands, coinfection patterns differed between sites and among individuals, with the proportion of coinfected raccoons being greater in the undisturbed site. This study shows that raccoons are hosts for several novel hemoplasmas and that habitat type influences infection patterns.IMPORTANCE This study provides information about novel hemoplasmas identified in raccoons (Procyon lotor), which can be used for assessments of the prevalence of these hemoplasmas in raccoon populations and for future studies on the potential pathogenic impacts of these hemoplasmas on raccoon health. Raccoons from the undisturbed habitat had a higher prevalence of hemoplasma infection than urban raccoons. There does not appear to be cross-species transmission of hemotropic mycoplasmas between urban raccoons and feral cats. Raccoons appear to be hosts for several novel hemoplasmas, and habitat type influences infection patterns.

Modelling the influence of host community composition in a sylvatic Trypanosoma cruzi system.

Species composition of wild reservoir hosts can influence the transmission and maintenance of multi-host vector borne pathogens. The 'pace of life' hypothesis proposes that the life history strategy of reservoir hosts can influence pathogen transmission of vector borne generalist pathogens. We use empirical data to parameterize a mathematical model that investigates the impacts of host life history traits on vector transmission dynamics of the vector-borne multi-host parasite Trypanosoma cruzi in habitats characterized by different degrees of deforestation and varying host community structure. The model considers susceptible and infected vector and host populations. When comparing the proportion of vectors infected with T. cruzi predicted by the model with empirical data, we found a trend of increasing vector infection as anthropogenic landscape disturbance increases for both data and model output. The model's vector infection rates were significantly lower than empirical results, but when incorporating host congenital transmission in the model, vector infection approaches field data. We conclude that intervened habitats associated with r-selected host species communities predict higher proportions of infected vectors.

Hypervirulent Klebsiella pneumoniae in California Sea Lions ( Zalophus californianus): Pathologic Findings in Natural Infections.

Tissues of stranded California sea lions ( Zalophus californianus) naturally infected with a hyperviruluent strain of Klebsiella pneumoniae were examined by histopathology and immunohistochemistry against the K. pneumoniae K2 capsular antigen. In 7 of 8 animals, there was severe purulent bronchopneumonia, sometimes complicated by fibrinonecrotizing pleuritis with pyothorax. In affected areas of lung, large numbers of degenerate neutrophils and macrophages were admixed with rare large extracellular and intracellular gram-negative bacilli surrounded by a prominent capsule. Through serotyping, polymerase chain reaction, sequencing, and immunohistochemistry, these bacteria were confirmed to be a K2 serotype of K. pneumoniae. The same bacteria were identified through double immunolabeling within macrophages in blood vessels, lymph nodes, spleen, and liver. Intact K. pneumoniae were identified on epithelial surfaces of the nasopharyngeal, tracheal, and small intestine mucosae and within distal renal tubules. Our findings indicate that hypervirulent K. pneumoniae causes severe respiratory disease and intrahistiocytic bacteremia in California sea lions.

Potential Noncutaneous Sites of Chelonid Herpesvirus 5 Persistence and Shedding in Green Sea Turtles Chelonia mydas.

Chelonid herpesvirus 5 (ChHV5), the likely etiologic agent of sea turtle fibropapillomatosis (FP), is predicted to be unevenly distributed within an infected turtle, in which productive virus replication and virion shedding occurs in cutaneous tumor keratinocytes. In this study, we measured and compared ChHV5 DNA quantities in tumors, skin, urine, major organs, and nervous tissue samples from green turtles Chelonia mydas. These samples were taken from the carcasses of 10 juvenile green turtles with and without clinical signs of FP that stranded in Florida during 2014. Quantitative PCR for ChHV5 UL30 was used to identify ChHV5 DNA in tumors, skin, heart, kidney, nerves, and urine sampled from five out of five FP-positive and three out of five FP-free turtles. The most frequently co-occurring sites were cutaneous tumor and kidney (n = 4). Novel data presented here include the identification of ChHV5 DNA in kidney, heart, and nerve samples from three FP-free turtles. These data support candidate nontumored anatomic sites of ChHV5 DNA localization and mobilization during two different disease states that may be involved in the ChHV5 infection cycle. Received September 8, 2016; accepted April 17, 2017.

Cutaneous Leishmaniasis in dogs: is high seroprevalence indicative of a reservoir role?

American cutaneous leishmaniasis (ACL) is a complex disease with a rich diversity of animal host species. This diversity imposes a challenge, since understanding ACL transmission requires the adequate identification of reservoir hosts, those species able to be a source of additional infections. In this study we present results from an ACL cross-sectional serological survey of 51 dogs (Canis familiaris), where we used diagnostic tests that measure dog's exposure to Leishmania spp. parasites. We did our research in Panamá, at a village that has undergone significant ecosystem level transformations. We found an ACL seroprevalence of 47% among dogs, and their exposure was positively associated with dog age and abundance of sand fly vectors in the houses of dog owners. Using mathematical models, which were fitted to data on the proportion of positive tests as function of dog age, we estimated a basic reproductive number (R 0 ± s.e.) of 1·22 ± 0·09 that indicates the disease is endemically established in the dogs. Nevertheless, this information by itself is insufficient to incriminate dogs as ACL reservoirs, given the inability to find parasites (or their DNA) in seropositive dogs and previously reported failures to experimentally infect vectors feeding on dogs with ACL parasites.

Case descriptions of fibropapillomatosis in rehabilitating loggerhead sea turtles Caretta caretta in the southeastern USA.

Fibropapillomatosis (FP) is a debilitating neoplastic disease that affects all species of hard-shelled sea turtles, including loggerhead turtles Caretta caretta. FP can represent an important clinical concern in rehabilitating turtles, since managing these infectious lesions often requires special husbandry provisions including quarantine, and FP may affect clinical progression, extend rehabilitation duration, and complicate prognoses. Here we describe cases of rehabilitating loggerhead turtles with FP (designated FP+). Medical records of FP+ loggerhead cases from 3 sea turtle rehabilitation facilities in the southeastern USA were reviewed. Between 2001 and 2014, FP was observed in 8 of 818 rehabilitating loggerhead turtles (0.98% overall prevalence in admitted patients). FP+ loggerhead size classes represented were large juvenile (straight carapace length, SCL: 58.1-80 cm; n=7) and adult (SCL>87 cm; n=1). Three turtles presented with FP, and 5 developed tumors during rehabilitation within a range of 45 to 319 d. Sites of new tumor growth included the eyes, sites of trauma, neck, and glottis. FP+ turtles were scored as mildly (3/8), moderately (4/8), or heavily (1/8) afflicted. The mean total time in rehabilitation was 476±355 d (SD) (range: 52-1159 d). Six turtles were released without visible evidence of FP, 1 turtle was released with mild FP, and 1 turtle with internal FP was euthanized. Clinical decision-making for FP+ loggerhead patients can be aided by such information as time to tumor development, anatomic locations to monitor for new tumor growth, husbandry considerations, diagnostic and treatment options, and comparisons to FP in rehabilitating green turtles Chelonia mydas.

Risk factors associated with Trypanosoma cruzi exposure in domestic dogs from a rural community in Panama.

Chagas disease, caused by Trypanosoma cruzi infection, is a zoonosis of humans, wild and domestic mammals, including dogs. In Panama, the main T. cruzi vector is Rhodnius pallescens, a triatomine bug whose main natural habitat is the royal palm, Attalea butyracea. In this paper, we present results from three T. cruzi serological tests (immunochromatographic dipstick, indirect immunofluorescence and ELISA) performed in 51 dogs from 24 houses in Trinidad de Las Minas, western Panama. We found that nine dogs were seropositive (17.6% prevalence). Dogs were 1.6 times more likely to become T. cruzi seropositive with each year of age and 11.6 times if royal palms where present in the peridomiciliary area of the dog's household or its two nearest neighbours. Mouse-baited-adhesive traps were employed to evaluate 12 peridomestic royal palms. All palms were found infested with R. pallescens with an average of 25.50 triatomines captured per palm. Of 35 adult bugs analysed, 88.6% showed protozoa flagellates in their intestinal contents. In addition, dogs were five times more likely to be infected by the presence of an additional domestic animal species in the dog's peridomiciliary environment. Our results suggest that interventions focused on royal palms might reduce the exposure to T. cruzi infection.

Flight behavior and performance of Rhodnius pallescens (Hemiptera: Reduviidae) on a tethered flight mill.

ABSTRACT Flight dispersal of the triatomine bug species Rhodnius pallescens Barber, the principal vector of Chagas disease in Panama, is an important mechanism for spreading Trypanosoma cruzi, causative agent of Chagas disease. This study measures R. pallescens flight performance using a tethered flight mill both when uninfected, and when infected with T. cruzi or Trypanosoma rangeli. Forty-four out of the 48 (91.7%) insects initiated flight across all treatments, and trypanosome infection did not significantly impact flight initiation. Insects from all treatments flew a cumulative distance ranging from 0.5 to 5 km before fatiguing. The median cumulative distance flown before insect fatigue was higher in T. cruzi- and T. rangeli-infected insects than in control insects; however, this difference was not statistically significant. There was a positive relationship between parasite load ingested and time until flight initiation in T. rangeli-infected bugs, and T. rangeli- and T. cruzi-infected females flew significantly faster than males at different time points. These novel findings allow for a better understanding of R. pallescens dispersal ability and peridomestic management strategies for the prevention of Chagas disease in Panama.

Factors influencing survivorship of rehabilitating green sea turtles (Chelonia mydas) with fibropapillomatosis.

Marine turtle fibropapillomatosis (FP) is a debilitating, infectious neoplastic disease that has reached epizootic proportions in several tropical and subtropical populations of green turtles (Chelonia mydas). FP represents an important health concern in sea turtle rehabilitation facilities. The objectives of this study were to describe the observed epidemiology, biology, and survival rates of turtles affected by FP (FP+ turtles) in a rehabilitation environment; to evaluate clinical parameters as predictors of survival in affected rehabilitating turtles; and to provide information about case progression scenarios and potential outcomes for FP+ sea turtle patients. A retrospective case series analysis was performed using the medical records of the Georgia Sea Turtle Center (GSTC), Jekyll Island, Georgia, USA, during 2009-2013. Information evaluated included signalment, morphometrics, presenting complaint, time to FP onset, tumor score (0-3), co-morbid conditions, diagnostic test results, therapeutic interventions, and case outcomes. Overall, FP was present in 27/362 (7.5%) of all sea turtles admitted to the GSTC for rehabilitation, either upon admittance or during their rehabilitation. Of these, 25 were green and 2 were Kemp's ridley turtles. Of 10 turtles that had only plaque-like FP lesions, 60% had natural tumor regression, all were released, and they were significantly more likely to survive than those with classic FP (P = 0.02 [0.27-0.75, 95% CI]). Turtles without ocular FP were eight times more likely to survive than those with ocular FP (odds ratio = 8.75, P = 0.032 [1.21-63.43, 95% CI]). Laser-mediated tumor removal surgery is the treatment of choice for FP+ patients at the GSTC; number of surgeries was not significantly related to case outcome.

First Report of Chagas Disease Vector Species Triatoma sanguisuga (Hemiptera: Reduviidae) Infected with Trypanosoma cruzi in Delaware.

In July and October 2023, two live triatomine bugs were found inside a home in New Castle County, Delaware. The bugs were identified as Triatoma sanguisuga, the most widespread triatomine bug species in the United States. Triatoma sanguisuga is a competent vector of Trypanosoma cruzi, the causative agent of Chagas disease. The two specimens were tested via real-time PCR (qPCR) for infection with T. cruzi, and one of the specimens was positive. Despite T. sanguisuga being endemic to the area, attainment of accurate species identification and T. cruzi testing of the bugs required multiple calls to federal, state, private, and academic institutions over several months. This constitutes the first report of T. sanguisuga infected with T. cruzi in Delaware. In addition, this is the first published report of T. sanguisuga in New Castle County, the northernmost and most densely populated county in Delaware. New Castle County still conforms to the described geographic range of T. sanguisuga, which spans from Texas to the East Coast of the United States. The T. cruzi infection prevalence of the species has not been studied in the northeastern United States, but collections in southern states have found prevalences as high as 60%. The Delaware homeowner's lengthy pursuit of accurate information about the vector highlights the need for more research on this important disease vector in Delaware.

Plasma and interstitial fluid antibiotic levels of subcutaneously implanted compounded florfenicol calcium sulfate beads in New Zealand White rabbits (Oryctolagus cuniculus).

OBJECTIVE: To determine antibiotic levels in plasma and interstitial fluid (ISF) after SC placement of compounded florfenicol (FF) calcium sulfate beads (CSBs) in New Zealand White rabbits (Oryctolagus cuniculus). ANIMALS: 6 juvenile female rabbits (n = 5 treatment and 1 control). METHODS: An ultrafiltration probe and CSBs were placed SC in 6 rabbits (n = 5 for FF CSBs and 1 for control CSBs). Plasma (3, 6, 12, 24, and 48 hours and 7, 14, and 21 days) and ISF (daily for 21 days) samples were collected, and FF was measured by HPLC for pharmacokinetic analysis. Hematology, biochemistry, and histopathology were assessed. RESULTS: Means ± SD for the area under the curve, maximum concentration, time of maximum concentration, terminal half-life, and mean residence time to the last data point for plasma and ISF were 16.63 ± 8.16 and 17,902 ± 7,564 h·µg/mL, 0.79 ± 0.38 and 245 ± 223 µg/mL, 2.90 ± 0.3 and 59 ± 40 hours, 30.81 ± 16.9 and 27.3 ± 9.39 hours, 23.4 ± 10 and 73.7 ± 13 hours, respectively. Plasma FF was < 2 µg/mL at all time points. The ISF FF remained > 8 µg/mL for 109.98 to 231.58 hours. One rabbit death occurred during treatment, but the cause of death was undetermined. Local tissue inflammation was present, but no clinically significant systemic adverse effects were found on hematology, biochemistry, or histopathology in the remaining rabbits. CLINICAL RELEVANCE: Florfenicol CSBs maintained antibiotic concentrations in ISF at levels likely to be effective against bacteria sensitive to > 8 µg/mL for 5 to 10 days while maintaining low (< 2 µg/mL) plasma levels. Florfenicol CSBs may be effective for local antibiotic treatment in rabbit abscesses.

An Acute Mortality Event Associated with Novel Macrorhabdus ornithogaster Infection and Underlying Factors in a Newly-Established Captive Group of American White Ibis (Eudocimus albus) Nestlings.

Twenty-four American white ibis (Eudocimus albus) nestlings were collected in Florida (USA) on 17 April 2017 to establish a captive flock. On 7 May 2017, three birds died suddenly, following severe lethargy, hemorrhaging from the mouth and nares, anorexia, and production of bright-green colored feces. An additional ibis with delayed growth and pathological fractures was euthanized 18 May 2017. Severe ventriculitis associated with Macrorhabdus ornithogaster was noted in all four birds, bacterial sepsis was confirmed in one bird by culture and histologic examination, and bacterial endotoxemia was suspected in two birds based on gross and histologic examination, but no bacteria were isolated from these birds. Birds also had vitamin E liver levels consistent with coagulopathy previously described in pelicans. We sampled feces from 91 adult, free-living, healthy ibis in Florida in July 2017 and found 71% were shedding organisms with morphologic characteristics consistent with Macrorhabdus sp. Molecular characterization of the ibis-origin M. ornithogaster showed it was phylogenetically related to numerous M. ornithogaster sequences. It is unknown if M. ornithogaster infection resulted in clinical disease as a result of dietary or stress-related dysbiosis, or other factors. Macrorhabdus-associated disease has not previously been confirmed in wading birds. We discuss potential associations of gastric M. ornithogaster infection with morbidity and mortality in these cases and highlight the need for additional studies on this pathogen in free-living birds.

Land reversion and zoonotic spillover risk.

Deforestation alters wildlife communities and modifies human-wildlife interactions, often increasing zoonotic spillover potential. When deforested land reverts to forest, species composition differences between primary and regenerating (secondary) forest could alter spillover risk trajectory. We develop a mathematical model of land-use change, where habitats differ in their relative spillover risk, to understand how land reversion influences spillover risk. We apply this framework to scenarios where spillover risk is higher in deforested land than mature forest, reflecting higher relative abundance of highly competent species and/or increased human-wildlife encounters, and where regenerating forest has either very low or high spillover risk. We find the forest regeneration rate, the spillover risk of regenerating forest relative to deforested land, and how rapidly regenerating forest regains attributes of mature forest determine landscape-level spillover risk. When regenerating forest has a much lower spillover risk than deforested land, reversion lowers cumulative spillover risk, but instaneous spillover risk peaks earlier. However, when spillover risk is high in regenerating and cleared habitats, landscape-level spillover risk remains high, especially when cleared land is rapidly abandoned then slowly regenerates to mature forest. These results suggest that proactive wildlife management and awareness of human exposure risk in regenerating forests could be important tools for spillover mitigation.

Both consumptive and non-consumptive effects of predators impact mosquito populations and have implications for disease transmission.

Predator-prey interactions influence prey traits through both consumptive and non-consumptive effects, and variation in these traits can shape vector-borne disease dynamics. Meta-analysis methods were employed to generate predation effect sizes by different categories of predators and mosquito prey. This analysis showed that multiple families of aquatic predators are effective in consumptively reducing mosquito survival, and that the survival of Aedes, Anopheles, and Culex mosquitoes is negatively impacted by consumptive effects of predators. Mosquito larval size was found to play a more important role in explaining the heterogeneity of consumptive effects from predators than mosquito genus. Mosquito survival and body size were reduced by non-consumptive effects of predators, but development time was not significantly impacted. In addition, Culex vectors demonstrated predator avoidance behavior during oviposition. The results of this meta-analysis suggest that predators limit disease transmission by reducing both vector survival and vector size, and that associations between drought and human West Nile virus cases could be driven by the vector behavior of predator avoidance during oviposition. These findings are likely to be useful to infectious disease modelers who rely on vector traits as predictors of transmission.

Mosquitoes are often referred to as the deadliest animals on earth because some species spread malaria, West Nile virus or other dangerous diseases when they bite humans and other animals. Adult mosquitoes fly to streams, ponds and other freshwater environments to lay their eggs. When the eggs hatch, the young mosquitoes live in the water until they are ready to grow wings and transform into adults. In the water, the young mosquitoes are particularly vulnerable to being eaten by dragonfly larvae, fish and other predators. When adult females are choosing where to lay their eggs, they can use their sense of smell to detect these predators and attempt to avoid them. Along with eating the mosquitoes, the predators may also reduce mosquito populations in other ways. For example, predators can disrupt feeding among young mosquitoes, which may affect the time that it takes for them to grow into adults or the size of their bodies once they reach the adult stage. Although the impacts of different predators have been tested separately in multiple settings, the overall effects of predators on the ability of mosquitoes to spread diseases to humans remain unclear. To address this question, Russell, Herzog et al. used an approach called meta-analysis on data from previous studies. The analysis found that along with increasing the death rates of mosquitoes, the presence of predators also leads to a reduction in the body size of those mosquitoes that survive, causing them to have shorter lifespans and fewer offspring. Russell, Herzog et al. found that one type of mosquito known as Culex ­ which carries West Nile virus ­ avoided laying its eggs near predators. During droughts, increased predation in streams, ponds and other aquatic environments may lead adult female Culex mosquitoes to lay their eggs closer to residential areas with fewer predators. Russell, Herzog et al. propose that this may be one reason why outbreaks of West Nile virus in humans are more likely to occur during droughts. In the future, these findings may help researchers to predict outbreaks of West Nile virus, malaria and other diseases carried by mosquitoes more accurately. Furthermore, the work of Russell, Herzog et al. provides examples of mosquito predators that could be used as biocontrol agents to decrease numbers of mosquitoes in certain regions.

Cat Scratch Disease: 9 Years of Experience at a Pediatric Center.

Background: A more complete understanding of the epidemiology, risk factors, and clinical features of cat scratch disease (CSD) in children could help guide patient care. Methods: We conducted a retrospective analysis of children presenting to a tertiary pediatric hospital system in Atlanta, Georgia between January 1, 2010 and December 31, 2018 who had serology, polymerase chain reaction, and/or cytopathological results consistent with a Bartonella henselae infection. We also retrospectively reviewed veterinary diagnostic results performed at the University of Georgia from 2018 to 2020 to ascertain the burden of bartonellosis in companion animals within the state. Results: We identified 304 children with CSD over 9 years with the largest proportion of diagnoses made during August (41 of 304, 13.5%) and September (47 of 304, 15.5%). The median age of child cases was 8.1 years (interquartile range [IQR], 5.4-12.1); 156 (51.3%) were female; 242 of 262 (92.4%) reported feline exposure; and 55 of 250 (22%) reported canine exposure of those with exposure histories documented in the medical record. Although lymphadenopathy was present on physical examination in the majority of cases (78.8%), atypical presentations lacking lymphadenopathy were also common (63 of 304, 20.7%). Among children with radiographic imaging, 20 of 55 (36.4%) had splenomegaly and 21 of 55 (38.1%) had splenic and/or hepatic microabscesses. Among veterinary data, Bartonella seroprevalence was 12 of 146 (8.2%), all among canines, with a geographic distribution that spanned the state of Georgia. Conclusions: Distinguishing clinical features of CSD included subacute regional lymphadenopathy in school-aged children in the late summer, almost all of whom had cat exposure. Atypical clinical manifestations of CSD were also commonly identified.

TEMPORAL AND SPATIAL PATTERNS IN CANINE DISTEMPER VIRUS CASES IN WILDLIFE DIAGNOSED AT THE SOUTHEASTERN COOPERATIVE WILDLIFE DISEASE STUDY, 1975-2019.

Canine distemper is a high-impact disease of many mammal species and has caused substantial carnivore population declines. Analysis was conducted on passive surveillance data of canine distemper (CDV)-positive wild mammal cases submitted to the Southeastern Cooperative Wildlife Disease Study, Athens, Georgia, US, between January 1975 and December 2019. Overall, 964 cases from 17 states were CDV positive, including 646 raccoons (Procyon lotor), 254 gray foxes (Urocyon cinereoargenteus), 33 striped skunks (Mephitis mephitis), 18 coyotes (Canis latrans), four red foxes (Vulpes vulpes), three gray wolves (Canis lupus), three American black bears (Ursus americanus), two American mink (Mustela vison), and one long-tailed weasel (Mustela frenata). Raccoon and gray fox case data from the state of Georgia (n=441) were selected for further analysis. Autoregressive integrated moving average models were developed predicting raccoon and gray fox case numbers. The best-performing model for gray foxes used numbers of gray fox CDV cases from the previous 2 mo and of raccoon cases in the present month to predict the numbers of gray fox cases in the present month. The best-performing model for raccoon prediction used numbers of raccoon CDV cases from the previous month and of gray fox cases in the present month and previous 2 mo to predict numbers of raccoon cases in the present month. Temporal trends existed in CDV cases for both species, with cases more likely to occur during the breeding season. Spatial clustering of cases was more likely to occur in areas of medium to high human population density; fewer cases occurred in both the most densely populated and sparsely populated areas. This pattern was most prominent for raccoons, which may correspond to high transmission rates in suburban areas, where raccoon population densities are probably highest, possibly because of a combination of suitable habitat and supplemental resources.