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Among the key ingredients are physician ownership, a strong strategic direction and a commitment to high-quality patient care. [ABSTRACT FROM AUTHOR]

Managed care has pushed physicians into new practice arrangements, but none is positioned for success like the physician-owned group. [ABSTRACT FROM AUTHOR]

Floodplains represent critical nursery habitats for a variety of fish species due to their highly productive food webs, yet few tools exist to quantify the extent to which these habitats contribute to ecosystem-level production. Here we conducted a large-scale field experiment to characterize differences in food web composition and stable isotopes (δ¹³C, δ¹⁵N, δ³⁴S) for salmon rearing on a large floodplain and adjacent river in the Central Valley, California, USA. The study covered variable hydrologic conditions including flooding (1999, 2017), average (2016), and drought (2012-2015). In addition, we determined incorporation rates and tissue fractionation between prey and muscle from fish held in enclosed locations (experimental fields, cages) at weekly intervals. Finally, we measured δ³⁴S in otoliths to test if these archival biominerals could be used to reconstruct floodplain use. Floodplain-reared salmon had a different diet composition and lower δ13C and δ³⁴S (δ¹³C = -33.02±2.66‰, δ³⁴S = -3.47±2.28‰; mean±1SD) compared to fish in the adjacent river (δ¹³C = -28.37±1.84‰, δ³⁴S = +2.23±2.25‰). These isotopic differences between habitats persisted across years of extreme droughts and floods. Despite the different diet composition, δ¹⁵N values from prey items on the floodplain (δ¹⁵N = 7.19±1.22‰) and river (δ¹⁵N = 7.25±1.46‰) were similar, suggesting similar trophic levels. The food web differences in δ13C and δ³⁴S between habitats were also reflected in salmon muscle tissue, reaching equilibrium between 24-30 days (2014, δ¹³C = -30.74±0.73‰, δ³⁴S = -4.6±0.68‰; 2016, δ¹³C = -34.74 ±0.49‰, δ³⁴S = -5.18±0.46‰). δ³⁴S measured in sequential growth bands in otoliths recorded a weekly time-series of shifting diet inputs, with the outermost layers recording time spent on the floodplain (δ³⁴S = -5.60±0.16‰) and river (δ³⁴S = 3.73±0.98‰). Our results suggest that δ¹³C and δ³⁴S can be used to differentiate floodplain and river rearing habitats used by native fishes, such as Chinook Salmon, across different hydrologic conditions and tissues. Together these stable isotope analyses provide a toolset to quantify the role of floodplains as fish habitats., Competing Interests: The authors have declared that no competing interests exist.

Many estuarine ecosystems and the fish communities that inhabit them have undergone substantial changes in the past several decades, largely due to multiple interacting stressors that are often of anthropogenic origin. Few are more impactful than droughts, which are predicted to increase in both frequency and severity with climate change. In this study, we examined over five decades of fish monitoring data from the San Francisco Estuary, California, USA, to evaluate the resistance and resilience of fish communities to disturbance from prolonged drought events. High resistance was defined by the lack of decline in species occurrence from a wet to a subsequent drought period, while high resilience was defined by the increase in species occurrence from a drought to a subsequent wet period. We found some unifying themes connecting the multiple drought events over the 50-yr period. Pelagic fishes consistently declined during droughts (low resistance), but exhibit a considerable amount of resiliency and often rebound in the subsequent wet years. However, full recovery does not occur in all wet years following droughts, leading to permanently lower baseline numbers for some pelagic fishes over time. In contrast, littoral fishes seem to be more resistant to drought and may even increase in occurrence during dry years. Based on the consistent detrimental effects of drought on pelagic fishes within the San Francisco Estuary and the inability of these fish populations to recover in some years, we conclude that freshwater flow remains a crucial but not sufficient management tool for the conservation of estuarine biodiversity., (© 2020 The Authors. Ecological Applications published by Wiley Periodicals LLC on behalf of Ecological Society of America.)

While flow is known to be a major driver of estuarine ecosystems, targeted flow manipulations are rare because tidal systems are extremely variable in space and time, and because the necessary infrastructure is rarely available. In summer 2018 we used a unique water control structure in the San Francisco Estuary (SFE) to direct a managed flow pulse into Suisun Marsh, one of the largest contiguous tidal marshes on the west coast of the United States. The action was designed to increase habitat suitability for the endangered Delta Smelt Hypomesus transpacificus, a small osmerid fish endemic to the upper SFE. The approach was to operate the Suisun Marsh Salinity Control Gates (SMSCG) in conjunction with increased Sacramento River tributary inflow to direct an estimated 160 x 106 m3 pulse of low salinity water into Suisun Marsh during August, a critical time period for juvenile Delta Smelt rearing. Three-dimensional modeling showed that directing additional low salinity water into Suisun Marsh ("Flow Action") substantially increased the area of low salinity habitat for Delta Smelt that persisted beyond the period of SMSCG operations. Field monitoring showed that turbidity and chlorophyll were at higher levels in Suisun Marsh, representing better habitat conditions, than the upstream Sacramento River region throughout the study period. The Flow Action had no substantial effects on zooplankton abundance, nor did Suisun Marsh show enhanced levels of these prey species in comparison to the Sacramento River. Fish monitoring data suggested that small numbers of Delta Smelt colonized Suisun Marsh from the Sacramento River during the 2018 Flow Action. Comparison of the salinity effects of the Flow Action to historical catch data for Suisun Marsh further supported our hypothesis that the Flow Action would have some benefit for this rare species. Our study provides insight into both the potential use of targeted flow manipulations to support endangered fishes such as Delta Smelt, and into the general response of estuarine habitat to flow management., Competing Interests: Two of the authors (MM, AB) are employed by a private consulting firm. We confirm that this (commercial affiliation) does not alter our adherence to PLOS ONE policies on sharing data and materials.

Background: Coronal alignment of the tibial component determines functional outcome and survival in total knee arthroplasty (TKA). Innovative techniques for tibial instrumentation have been developed to improve accuracy and reduce the rate of outliers., Methods: In a prospective study, 300 patients were allocated to four different groups using a randomization process (two innovative and two conventional) techniques of tibial instrumentation (conventional: extramedullary, intramedullary; innovative: navigation and patient-specific instrumentation (PSI); n = 75 for each group). The aims were to reconstruct the medial proximal tibial angle (MPTA) to 90° and the mechanical tibio-femoral axis (mTFA) to 0°. Both angles were evaluated and compared between all groups three months after the surgery. Patients who presented with a postoperative mTFA > 3° were classified as outliers., Results: The navigation and intramedullary technique both demonstrated that they were significantly more precise in reconstructing a neutral mTFA and MPTA compared to the other two techniques. The odd's ratio (OR) for producing outliers was highest for the PSI method (PSI OR = 5.5, p < 0.05; extramedullary positioning OR = 3.7, p > 0.05; intramedullary positioning OR = 1.7, p > 0.05; navigation OR = 0.04, p < 0.05). We could only observe significant differences between pre- and postoperative MPTA in the navigation and intramedullary group. The MPTA showed a significant negative correlation with the mTFA in all groups preoperatively and in the extramedullary, intramedullary and PSI postoperatively., Conclusion: The navigation and intramedullary instrumentation provided the precise positioning of the tibial component. Outliers were most common within the PSI and extramedullary technique. Optimal alignment is dependent on the technique of tibial instrumentation and tibial component positioning determines the accuracy in TKA since mTFA correlated with MPTA pre- and postoperatively.

Rationale: Oxygen isotope ratios (δ 18 O values) of fish otoliths (ear bones) are valuable geochemical tracers of water conditions and thermal life history. Delta Smelt (Hypomesus transpacificus) are osmerid forage fish endemic to the San Francisco Estuary, California, USA, that are on the verge of extinction. These fish exhibit a complex life history that allows them to survive in a dynamic estuarine environment; however, a rapidly warming climate threatens this thermally sensitive species. Here we quantify the accuracy and precision of using δ 18 O values in otoliths to reconstruct the thermal life histories of Delta Smelt., Methods: Delta Smelt were reared for 360 days using three different water sources with different ambient δ 18 O water values (-8.75‰, -5.28‰, and -4.06‰) and different water temperatures (16.4°C, 16.7°C, 18.7°C, and 20.5°C). Samples were collected after 170 days (n = 28) and 360 days (n = 14) post-hatch. In situ δ 18 O values were measured from the core of the otolith to the dorsal edge using secondary ion mass spectrometry (SIMS) to reconstruct temporally resolved thermal life histories., Results: The δ 18 O otolith values for Delta Smelt varied as a linear inverse function of water temperature: 1000 ln α = 18.39 (±0.43, 1SE)(10 3 TK -1 ) - 34.56 (±1.49, 1SE) and δ 18 O otolith(VPDB)  - δ 18 O water (VPDB)  = 31.34(±0.09, 1SE) - 0.19(±0.01, 1SE) × T ° C. When the ambient δ 18 O water value is known, this species-specific temperature-dependent oxygen isotope fractionation model facilitated the accurate (0.25°C) and precise (±0.37°C, 2σ) reconstruction of the water temperature experienced by the fish. In contrast, the use of existing general fractionation equations resulted in inaccurate temperature reconstructions., Conclusions: The species-specific δ 18 O otolith fractionation equation allowed for accurate and precise reconstructions of water temperatures experienced by Delta Smelt. Characterization of ambient δ 18 O water values remains a critical next step for reconstructing thermal life histories of wild Delta Smelt. This tool will provide new insights into habitat utilization, potential thermal refugia, and resilience to future warming for this critically endangered fish., (© 2019 John Wiley & Sons, Ltd.)

When inundated by floodwaters, river floodplains provide critical habitat for many species of fish and wildlife, but many river valleys have been extensively leveed and floodplain wetlands drained for flood control and agriculture. In the Central Valley of California, USA, where less than 5% of floodplain wetland habitats remain, a critical conservation question is how can farmland occupying the historical floodplains be better managed to improve benefits for native fish and wildlife. In this study fields on the Sacramento River floodplain were intentionally flooded after the autumn rice harvest to determine if they could provide shallow-water rearing habitat for Sacramento River fall-run Chinook salmon (Oncorhynchus tshawytscha). Approximately 10,000 juvenile fish (ca. 48 mm, 1.1 g) were reared on two hectares for six weeks (Feb-March) between the fall harvest and spring planting. A subsample of the fish were uniquely tagged to allow tracking of individual growth rates (average 0.76 mm/day) which were among the highest recorded in fresh water in California. Zooplankton sampled from the water column of the fields were compared to fish stomach contents. The primary prey was zooplankton in the order Cladocera, commonly called water fleas. The compatibility, on the same farm fields, of summer crop production and native fish habitat during winter demonstrates that land management combining agriculture with conservation ecology may benefit recovery of native fish species, such as endangered Chinook salmon.

Iguanomorpha (stem + crown Iguania) is a diverse squamate clade with members that predominate many modern American lizard ecosystems. However, the temporal and palaeobiogeographic origins of its constituent crown clades (e.g. Pleurodonta (basilisks, iguanas, and their relatives)) are poorly constrained, mainly due to a meagre Mesozoic-age fossil record. Here, we report on two nearly complete skeletons from the Late Cretaceous (Campanian) of North America that represent a new and relatively large-bodied and possibly herbivorous iguanomorph that inhabited a semi-arid environment. The new taxon exhibits a mosaic of anatomical features traditionally used in diagnosing Iguania and non-iguanian squamates (i.e. Scleroglossa; e.g. parietal foramen at the frontoparietal suture, astragalocalcaneal notch in the tibia, respectively). Our cladistic analysis of Squamata revealed a phylogenetic link between Campanian-age North American and East Asian stem iguanomorphs (i.e. the new taxon + Temujiniidae). These results and our evaluation of the squamate fossil record suggest that crown pleurodontans were restricted to the low-latitude Neotropics prior to their early Palaeogene first appearances in the mid-latitudes of North America., (© 2017 The Author(s).)

A new fossil showing affinities with extant Laemanctus offers the first clear evidence for a casquehead lizard (Corytophanidae) from the Eocene of North America. Along with Geiseltaliellus from roughly coeval rocks in central Europe, the new find further documents the tropical fauna present during greenhouse conditions in the northern mid-latitudes approximately 50 million years ago (Ma). Modern Corytophanidae is a neotropical clade of iguanian lizards ranging from southern Mexico to northern South America.

The effect of predation on native fish by introduced species in the San Francisco Estuary-Delta (SFE) has not been thoroughly studied despite its potential to impact species abundances. Species-specific quantitative PCR (qPCR) is an accurate method for identifying species from exogenous DNA samples. Quantitative PCR assays can be used for detecting prey in gut contents or faeces, discriminating between cryptic species, or detecting rare aquatic species. We designed ten TaqMan qPCR assays for fish species from the SFE watershed most likely to be affected by non-native piscivores. The assays designed are highly specific, producing no signal from co-occurring or related species, and sensitive, with a limit of detection between 3.2 and 0.013 pg/μL of target DNA. These assays will be used in conjunction with a high-throughput qPCR platform to compare predation rates between native and non-native piscivores and assess the impacts of predation in the system., (© 2014 John Wiley & Sons Ltd.)

We describe an unusual squamate fossil from the Green River Formation (Uintan, Eocene) from the Piceance Creek Basin, Colorado, USA. The new specimen, USNM PAL 540708, is a small fossil squamate skin lacking skeletal elements. It is preserved as a part and counterpart in fine-grained limestone. Recovery of a fossil organism's skin (not a shed, but a true skin) is unusual and is most often accompanied by bone preservation. Phylogenetic analysis of a combined morphology (phenotype) and genetic data set reveals that USNM PAL 540708 is a shinisaur and reaffirms that shinisaurs are more closely related to varanids than to Xenosaurus. Shinisaur fossils are very rare, with only three species having been described (Dalinghosaurus longidigitus, Bahndwivici ammoskius, and Merkurosaurus ornatus). Despite differences in the relative size of scales, the new fossil demonstrates that shinisaurs have remained unchanged in the distribution of scales and patterns of scale size during the Cenozoic. This, paired with the osteological similarity between another Green River fossil (Bahndwivici ammoskius) demonstrates considerable overall conservatism within shinisaurs over the past 50 million years., (Copyright © 2014 Wiley Periodicals, Inc.)

Background: Varanidae is a clade of tiny (<20 mm pre-caudal length [PCL]) to giant (>600 mm PCL) lizards first appearing in the Cretaceous. True monitor lizards (Varanus) are known from diagnostic remains beginning in the early Miocene (Varanus rusingensis), although extremely fragmentary remains have been suggested as indicating earlier Varanus. The paleobiogeographic history of Varanus and timing for origin of its gigantism remain uncertain., Methodology/principal Findings: A new Varanus from the Mytilini Formation (Turolian, Miocene) of Samos, Greece is described. The holotype consists of a partial skull roof, right side of a braincase, partial posterior mandible, fragment of clavicle, and parts of six vertebrae. A cladistic analysis including 83 taxa coded for 5733 molecular and 489 morphological characters (71 previously unincluded) demonstrates that the new fossil is a nested member of an otherwise exclusively East Asian Varanus clade. The new species is the earliest-known giant (>600 mm PCL) terrestrial lizard. Importantly, this species co-existed with a diverse continental mammalian fauna., Conclusions/significance: The new monitor is larger (longer) than 99% of known fossil and living lizards. Varanus includes, by far, the largest limbed squamates today. The only extant non-snake squamates that approach monitors in maximum size are the glass-snake Pseudopus and the worm-lizard Amphisbaena. Mosasauroids were larger, but exclusively marine, and occurred only during the Late Cretaceous. Large, extant, non-Varanus, lizards are limbless and/or largely isolated from mammalian competitors. By contrast, our new Varanus achieved gigantism in a continental environment populated by diverse eutherian mammal competitors.

Anguimorpha is a clade of limbed and limbless squamates with ca. 196 extant species and a known fossil record spanning the past 130 million years. Morphology-based and molecule-based phylogenetic analyses disagree on several key points. The analyses differ consistently in the placements of monstersaurs (e.g. Gila Monsters), shinisaurs (Crocodile Lizards), the anguid Anniella (American Legless Lizards), carusioids (Knobby Lizards), and the major clades within Varanus (Monitor Lizards). Given different data sources with such different phylogenetic hypotheses, Anguimorpha is an excellent candidate for a combined phylogenetic analysis. We constructed a data matrix consisting of 175 fossil and extant anguimorphs, and 2281 parsimony-informative characters (315 morphological characters and 1969 molecular characters). We analysed these data using the computer program TNT using the "new technology search" with the ratchet. Our result is novel and shows similarities with both morphological and molecular trees, but is identical to neither. We find that a global combined evidence analysis (GCA) does not recover a holophyletic Varanoidea, but omission of fossil taxa reveals cryptic molecular support for that group. We describe these results and others from global morphological analysis, extant-only morphological analysis, molecular data-only analyses, combined evidence analysis of extant taxa, and GCA. © The Willi Hennig Society 2010., (© The Willi Hennig Society 2010.)

This review examines the contribution of research on fishes to the growing field of behavioural syndromes. Current knowledge of behavioural syndromes in fishes is reviewed with respect to five main axes of animal personality: (1) shyness-boldness, (2) exploration-avoidance, (3) activity, (4) aggressiveness and (5) sociability. Compared with other taxa, research on fishes has played a leading role in describing the shy-bold personality axis and has made innovative contributions to the study of the sociability dimension by incorporating social network theory. Fishes are virtually the only major taxon in which behavioural correlations have been compared between populations. This research has guided the field in examining how variation in selection regime may shape personality. Recent research on fishes has also made important strides in understanding genetic and neuroendocrine bases for behavioural syndromes using approaches involving artificial selection, genetic mapping, candidate gene and functional genomics. This work has illustrated consistent individual variation in highly complex neuroendocrine and gene expression pathways. In contrast, relatively little work on fishes has examined the ontogenetic stability of behavioural syndromes or their fitness consequences. Finally, adopting a behavioural syndrome framework in fisheries management issues including artificial propagation, habitat restoration and invasive species, may promote restoration success. Few studies, however, have examined the ecological relevance of behavioural syndromes in the field. Knowledge of how behavioural syndromes play out in the wild will be crucial to incorporating such a framework into management practices., (© 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.)

Behavioural assays were conducted on newly emerged steelhead Oncorhynchus mykiss to investigate the presence of behavioural syndromes and to determine whether behavioural type in young fish predicts growth rate in a conventional hatchery rearing environment. Individual fry were consistent in their position choice and activity behaviours across safe and unsafe contexts, as well as among assays conducted on different days. Position choice and activity behaviours, however, were not necessarily correlated to each other. Both behaviours predicted feeding rates during behavioural assays, but there was no relationship between fry behaviour and subsequent growth rate or survival during the first 3 months of hatchery rearing. These results support the hypothesis that selection in captivity may be relaxed with respect to behavioural type rather than directional, allowing for increased behavioural variance in domesticated populations. Modest magnitudes of correlations among fry behaviours, however, suggest that behavioural type may be unstable at the onset of the juvenile feeding stage.

The furcula is a structure formed by the midline fusion of the clavicles. This is the element which is unique to theropods and is important for understanding the link between birds and other theropods. New specimens from basal theropods suggest that the furcula appeared very early in theropod history. We review furcula development, function, and morphology, as well as the anatomical terminology applied to it. Furcular morphology is highly variable in crown-group avians but is rather conserved among nonavian theropods. Here we review, or describe for the first time, the furculae in many nonavian theropods. Furculae occur in nearly all major clades of theropods, as shown by new theropod specimens from the Early Cretaceous of China and a close inspection of previously collected specimens. Informative phylogenetic characters pertaining to the furcula occur throughout Theropoda, though care should betake to consider taphonomic effects when describing furcular morphology., ((c) 2009 Wiley-Liss, Inc.)

The postcranial skeleton is poorly known for Shinisaurus crocodilurus, the Chinese crocodile lizard. Discrepancies exist between published accounts of Shinisaurus; moreover, comparisons with complete specimens show important differences from the published descriptions. Contrary to some publications, the axial skeleton variably consists of 26 or 27 presacral vertebrae, including eight cervical vertebrae. Humeral entepicondylar and ectepicondylar foramina are present, as are an epipubis and hypoischium, and the post-tubercular portion of the pubis is subequal in length to the proximal portion. Sesamoids are present in the knee, elbow, and between the penultimate phalanges and unguals. A cartilaginous strut joins the clavicles and interclavicle. Comparative investigation of extant anguimorphs add context to these observations and support the conclusion that Mosasauroidea possessed eight or more (rather than seven) cervical vertebrae. Overall, the postcranium of Shinisaurus is relatively unspecialized for Anguimorpha, although it may be diagnosed accurately by a combination of character states., ((c) 2004 Wiley-Liss, Inc.)

Abelisauroid predators have been recorded almost exclusively from South America, India and Madagascar, a distribution thought to document persistent land connections exclusive of Africa. Here, we report fossils from three stratigraphic levels in the Cretaceous of Niger that provide definitive evidence that abelisauroid dinosaurs and their immediate antecedents were also present on Africa. The fossils include an immediate abelisauroid antecedent of Early Cretaceous age (ca. 130-110 Myr ago), early members of the two abelisauroid subgroups (Noasauridae, Abelisauridae) of Mid-Cretaceous age (ca. 110 Myr ago) and a hornless abelisaurid skull of early Late Cretaceous age (ca. 95 Myr ago). Together, these fossils fill in the early history of the abelisauroid radiation and provide key evidence for continued faunal exchange among Gondwanan landmasses until the end of the Early Cretaceous (ca. 100 Myr ago).

On February 6, 1978, the largest New England blizzard of the century struck eastern Massachusetts. On request, four days later, the Center for Disease Control provided epidemiologic assistance. On-site disaster assistance provided decision-makers with immediate health surveillance information useful in helping the area return to normal. No outbreaks of infectious diseases and no significant increase in the number of deaths were observed in the week following the blizzard. Some of the deaths which occurred immediately after the blizzard might have been prevented if traffic had been banned earlier.

In 1983, the State Epidemiologists in 46 States completed a survey questionnaire describing the professional qualifications, training, and experience of State health department epidemiologists and the scope of participation by the State Epidemiologists and their staffs in public health programs. The survey identified 224 State health department epidemiologists (estimated U.S. ratio 1.1 per million population). A State health department epidemiologist was most often male (80 percent), frequently (57 percent) was a physician, had an average age of 41 years, and had worked as an epidemiologist for 9 years. Participation in public health programs (either by supervising or providing consultation) by the State Epidemiologists and their staffs focused mainly on general epidemiology and communicable disease programs; fewer than half had participated in programs relating to the health of women and children, chronic diseases, injuries, or in other programs directed towards preventing premature mortality. Recently, the State Epidemiologists have been trying to broaden their activities into these areas; however, the demands created by the acquired immunodeficiency syndrome (AIDS) will mostly likely slow this process. Based on the overall findings and collective experience, it was concluded that State health departments have too few epidemiologists to address the wide variety of important public health problems facing our communities. It was proposed that each State health department have at least four epidemiologists (including one or more physician epidemiologists) and at least one master's level biostatistician and that the epidemiologists-per-population ratio not be less than 1 per million.

The Subacute Sclerosing Panencephalitis Registry has compiled data from 453 instances of SSPE occurring in the United States from 1960 through 1976. The mean annual incidence during this period was 3.5 per 10 million persons under 20 years of age, 2.3 times higher for males than females, and 4.0 times higher for whites than blacks. Although the long-term pattern of incidence is unknown, the incidence of reported SSPE declined dramatically from 1970 to 1976. There are marked geographic variations of SSPE activity within the United States and also a higher incidence for children from farms (9.4 per 10 million persons under 20) compared with children from other rural domiciles (3.7 per 10 million), suburban children (2.9 per 10 million), and inner-city children (1.6 per 10 million). Available epidemiologic evidence suggests that some extrinsic factor, unrelated to measles or measles vaccine, is important in the pathogenesis of the disease.

During the first 10 days of February 1975, an Australian hitchhiker contracted Marburg virus disease while traveling through Rhodesia and died; the infection was subsequently passed to two other persons, who recovered. Investigators retraced the hitchhiker's steps in March and again in June 1975 in an effort to uncover the natural reservoir of the virus and determine how it was transmitted. Serum samples were collected from humans and animals wherever the patient had come in close contact with animals or insects. Arthropods of various types were collected in June 1975 and again in February 1976 for virus isolation attempts; at no time did the patient come in direct contact with nonhuman primates of any kind, or any other animals. Indirect contact with bats, monkeys, and birds through aerosols was possible, though at some distance. Direct contact with arthropods occurred throughout the trip; on several occasions it was notably severe. We believe that during this outbreak the first Marburg virus infection occurred by vector-borne transmission from an arthropod yet to be identified, and that patients 2 and 3 acquired the disease by exposure to the oropharyngeal secretions of patients 1 and 2, respectively. Studies are underway to identify the species of arthropod involved in this transmission.

Reported mumps in the United States has declined to all-time low levels following the increasingly widespread use of mumps-virus vaccine. Mumps vaccine has proven safe and effective. Its incorporation into combined live-virus vaccines, especially measles-mumps-rubella, has made mumps vaccination a practical and economically feasible component of routine immunization activities. Because of the favorable experience to date with mumps vaccine and the associated drop in mumps morbidity and mortality, mumps control programs likely will receive increasing public health attention in the coming years.

Between December 23, 1975, and March 31, 1976, 169 cases of measles were reported from Defiance County, Ohio, a small rural county in the northwest corner of the State. The outbreak spread from a single junior high school basketball player to eventually involve 19 of the 28 county schools. Among the affected schools, measles attack rates varied from 0.3-7.2% with a mean of 2.0%. A likely source of illness was determined for 160 of the 169 cases (95%). Intraschool transmission was most common, accounting for 97 of the 169 cases (57%) followed by sibling contact for 23 cases (14%). The pattern of measles spread was complex and would have been difficult to predict in advance even if surveillance systems reported each case the day it occurred. A control program held between February 2 and February 20, 1976, vaccinated 5145 of the 11,114 (46.3%) county schoolchildren. Forty-four cases of measles occurred 4 or more days following school clinics, 22 (50%) in children who requested measles vaccine at school clinics, 17 of whom were actually vaccinated. Most of the other cases occurred in students whose parents thought their children to be protected. Measles is a disease which spreads rapidly in a complex pattern over wide geographic areas. A control program vaccinating a large proportion of the children without definitive history of adequate vaccination or disease was apprently effective in curtailing the outbreak.