Impact of the Temperature on the Phenology of Diaphorina citri (Hemiptera: Liviidae) and on the Establishment of Tamarixia radiata (Hymenoptera: Eulophidae) in Urban Areas in the Lower Colorado Desert in Arizona.

The invasive pest Diaphorina citri Kuwayama was first detected in Arizona in 2009. Since late 2013, the parasitoid Tamarixia radiata (Waterson), the main biocontrol agent of D. citri, has been released as part of a biological control program on citrus grown in urban areas of two western Arizona counties in the lower Colorado desert environment. Here we report a 3-yr survey aimed at evaluation of T. radiata releases on D. citri populations and assess the impact of the climate conditions on the phenology of D. citri and on the establishment success of T. radiata. We also monitored the phenology of D. citri as part of this assessment on different citrus host species. We show that the high summer temperatures in the Arizona desert halt the development of D. citri for about 3 mo every year which appears to have limited the establishment and impact of T. radiata. At survey sites distant from release areas the parasitism rates over the season ranged from 0 to 75% and on average peaked around 50% in 2016 but it was low or absent in 2015 and 2017, respectively. We discuss the consequences of this phenology of D. citri in the desert areas for the prospects of long-term establishment of T. radiata and the management of this key citrus pest.

Community navigators reduce hospital utilization in super-utilizers.

OBJECTIVES: Super-utilizers place a significant burden on the healthcare system. Blending the roles of patient navigators and community health workers may address the clinical and social needs of these patients. This study evaluated the effectiveness of community navigators in reducing hospital utilization and costs among super-utilizers from a low-income area in Memphis, Tennessee. STUDY DESIGN: Controlled pre-post (difference-in-differences [DID]) design using Methodist Le Bonheur Healthcare electronic health records from 2013 to 2016. METHODS: Data were abstracted for 1 year pre- and post intervention for super-utilizers working with a community navigator (n = 159) and a control group of similar super-utilizers (n = 280). We compared utilization (hospital encounters, total hospital days, days between encounters, 30-day readmissions) and costs before and after working with a navigator for the intervention group with utilization and costs in a control group not working with a navigator and compared relative changes using a DID approach. RESULTS: Utilization and cost outcomes for intervention and control groups declined significantly from the pre- to postintervention periods. Relative to the control group, super-utilizers working with community navigators had an additional 13% reduction in hospital encounters (95% CI, -19% to -6%), 8% reduction in total hospital days (95% CI, -14% to -2%), and 9% increase in days between encounters (95% CI, 4%-15%). The intervention group also had additional reductions in 30-day readmissions (-18%; 95% CI, -44% to 22%) and costs (-$4903; 95% CI, -$13,579 to $3774), but these were not statistically significant. CONCLUSIONS: Community navigators can reduce subsequent hospital utilization in super-utilizers. Expansions of this model should examine the model's effectiveness in other populations and outcomes.