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An estimated 2.1 million U.S. adults are housed within approximately 5,000 correctional and detention facilities† on any given day (1). Many facilities face significant challenges in controlling the spread of highly infectious pathogens such as SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19). Such challenges include crowded dormitories, shared lavatories, limited medical and isolation resources, daily entry and exit of staff members and visitors, continual introduction of newly incarcerated or detained persons, and transport of incarcerated or detained persons in multiperson vehicles for court-related, medical, or security reasons (2,3). During April 22-28, 2020, aggregate data on COVID-19 cases were reported to CDC by 37 of 54 state and territorial health department jurisdictions. Thirty-two (86%) jurisdictions reported at least one laboratory-confirmed case from a total of 420 correctional and detention facilities. Among these facilities, COVID-19 was diagnosed in 4,893 incarcerated or detained persons and 2,778 facility staff members, resulting in 88 deaths in incarcerated or detained persons and 15 deaths among staff members. Prompt identification of COVID-19 cases and consistent application of prevention measures, such as symptom screening and quarantine, are critical to protecting incarcerated and detained persons and staff members.

The US's 64 CDC-funded immunization programs are at the forefront of efforts to improve the quality of adolescent vaccination services. We sought to understand immunization program managers' perspectives on partnering with healthcare systems to improve HPV vaccine uptake. Managers of 44 state and local immunization programs completed our online survey in 2019. Immunization managers strongly endorsed the importance of partnering with systems to improve HPV vaccine uptake (mean = 3.8/4.0), and most wanted to do so in the next year (mean = 3.5). Immunization managers reported that common barriers included difficulty contacting systems' leadership (57%), differing organizational cultures (52%), and time (52%). Many perceived systems as not prioritizing HPV vaccination (77%). Immunization managers expressed strong interest in participating in a training on partnering with systems (mean = 3.5). Overall, immunization managers are highly interested in partnering with systems to improve HPV vaccine uptake. Training and other support are needed to expand programs' capacity for such partnerships.PLAIN LANGUAGE SUMMARYImmunization managers are interested in partnering with healthcare systems to improve HPV vaccination. However, support may be needed to facilitate partnerships between immunization programs and healthcare systems.

Many US health departments (HDs) conduct in-person quality improvement (QI) coaching to help primary care clinics improve their HPV vaccine delivery systems and communication. Some HDs additionally conduct remote communication training to help vaccine prescribers recommend HPV vaccination more effectively. Our aim was to compare QI coaching and communication training on key implementation outcomes. In a cluster randomized trial, we offered 855 primary care clinics: 1) QI coaching; 2) communication training; or 3) both interventions combined. In each trial arm, we assessed adoption (proportion of clinics receiving the intervention), contacts per clinic (mean number of contacts needed for one clinic to adopt intervention), reach (median number of participants per clinic), and delivery cost (mean cost per clinic) from the HD perspective. More clinics adopted QI coaching than communication training or the combined intervention (63% vs 16% and 12%, both p.05). QI coaching required fewer contacts per clinic than communication training or the combined intervention (mean = 4.7 vs 29.0 and 40.4, both p.05). Communication training and the combined intervention reached more total staff per clinic than QI coaching (median= 5 and 5 vs 2, both p.05), including more prescribers (2 and 2 vs 0, both p.05). QI coaching cost $439 per adopting clinic on average, including follow up ($129/clinic), preparation ($73/clinic), and travel ($69/clinic). Communication training cost $1,287 per adopting clinic, with most cost incurred from recruitment ($653/clinic). QI coaching was lower cost and had higher adoption, but communication training achieved higher reach, including to influential vaccine prescribers.Our cluster randomized trial compared two interventions that health departments commonly use to increase HPV vaccination coverage: quality improvement (QI) coaching and physician communication training. We found that QI coaching cost less and was more often adopted by primary care clinics, but communication training reached more staff members per clinic, including vaccine prescribers. Findings provide health departments with data needed to weigh the implementation strengths and challenges of QI coaching and physician communication training for increasing HPV vaccination coverage.

BackgroundIn early 2020, an outbreak of coronavirus disease 2019 occurred among passengers and crew of the Diamond Princess cruise ship. During February 16–17, some US citizens, residents, and their partners voluntarily repatriated to the US from Japan.MethodsWe conducted a retrospective, longitudinal evaluation of repatriated travelers where the outcome of interest was a positive test for SARS-CoV-2. Travelers who tested positive for SARS-CoV-2 were isolated in hospitals or at home under county isolation orders and underwent serial testing by real-time reverse transcription polymerase chain reaction (RT-PCR) approximately every other day, as contemporaneous US guidance required two consecutive negative tests collected ≥24 hours apart and symptom improvement before release from isolation.ResultsAmong quarantined repatriated travelers, 14% tested positive for SARS-CoV-2. One-fifth of infected travelers initially tested negative but were identified on subsequent testing. All infected travelers remained asymptomatic or developed mild symptoms during isolation. Many travelers remained in prolonged isolation because of persistent viral detection based on contemporaneous policies.ConclusionOur findings support testing within 3-5 days after possible SARS-CoV-2 exposure to comprehensively identify infections and mitigate transmission and lend support to symptom- and time-based isolation recommendations, rather than test-based criteria.

Purpose and Objectives Quality improvement (QI) coaching improves human papillomavirus (HPV) vaccination coverage, but effects of coaching have been small, and little is known about how and when QI coaching works. To assess implementation outcomes and explore factors that might explain variation in outcomes, we conducted a process evaluation of a QI coaching intervention for HPV vaccination. Intervention Approach QI coaches received tools and training to support 4 core coaching competencies: 1) expertise in using clinic-level adolescent vaccination data to drive change, 2) knowledge of the evidence base to support change in HPV vaccination practice, 3) familiarity with improvement strategies and action planning, and 4) skill in building relationships. Evaluation Methods Our mixed methods evaluation involved collecting quantitative data through effort-tracking logs and gathering qualitative data through in-depth interviews with QI coaches (N = 11) who worked with 89 clinics in 3 US states. Data were collected on implementation outcomes and on contextual factors that might explain variations in those outcomes. Implementation outcomes included adoption by clinics, reach to providers and staff (ie, participation in the coaching visit), and implementation fidelity. Results States achieved either high adoption or high reach, but not both. For example, state A had high adoption with 94% of clinics accepting a coaching visit, but low reach with a median of 1 participant per clinic. In contrast, state C had lower adoption (29%, P < .01) than state A but higher reach (median of 4 participants per clinic, P < .01). Generally, states had high coaching protocol fidelity with the exception of advising on strategies and action planning. QI coaches described factors that might explain these variations, including strength of relationships with clinic staff and whether they recruited clinics directly or through large clinic networks. Implications for Public Health Our findings have implications for the design of future QI coaching initiatives, including how coaches recruit clinics to ensure full clinic engagement, refinements to coaching visits, and how QI coaches can effectively engage with clinic networks. Findings could inform future QI coaching interventions to strengthen their impact on public health.

Congregate work and residential locations are at increased risk for infectious disease transmission including respiratory illness outbreaks. SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), is primarily spread person to person through respiratory droplets. Nationwide, the meat and poultry processing industry, an essential component of the U.S. food infrastructure, employs approximately 500,000 persons, many of whom work in proximity to other workers (1). Because of reports of initial cases of COVID-19, in some meat processing facilities, states were asked to provide aggregated data concerning the number of meat and poultry processing facilities affected by COVID-19 and the number of workers with COVID-19 in these facilities, including COVID-19-related deaths. Qualitative data gathered by CDC during on-site and remote assessments were analyzed and summarized. During April 9-27, aggregate data on COVID-19 cases among 115 meat or poultry processing facilities in 19 states were reported to CDC. Among these facilities, COVID-19 was diagnosed in 4,913 (approximately 3%) workers, and 20 COVID-19-related deaths were reported. Facility barriers to effective prevention and control of COVID-19 included difficulty distancing workers at least 6 feet (2 meters) from one another (2) and in implementing COVID-19-specific disinfection guidelines.* Among workers, socioeconomic challenges might contribute to working while feeling ill, particularly if there are management practices such as bonuses that incentivize attendance. Methods to decrease transmission within the facility include worker symptom screening programs, policies to discourage working while experiencing symptoms compatible with COVID-19, and social distancing by workers. Source control measures (e.g., the use of cloth face covers) as well as increased disinfection of high-touch surfaces are also important means of preventing SARS-CoV-2 exposure. Mitigation efforts to reduce transmission in the community should also be considered. Many of these measures might also reduce asymptomatic and presymptomatic transmission (3). Implementation of these public health strategies will help protect workers from COVID-19 in this industry and assist in preserving the critical meat and poultry production infrastructure (4).

BACKGROUND Resource-limited countries in Africa experience blood shortages. Understanding clinical drivers of blood demand can inform strategies to increase blood availability. STUDY DESIGN AND METHODS From a national representative sample of 42 hospitals in Tanzania, patient records and requests for whole blood (WB) and red blood cells (RBCs) to treat anemia were analyzed using data collected prospectively from June through September 2013. Abstracted data included cause of anemia, number of requested units, clinical signs, and pretransfusion hemoglobin (Hb) levels. Weighted projections of nationwide drivers of blood demand for the year, 2013, were calculated. Mean posttransfusion Hb levels were estimated, and blood requests were assessed for clinical appropriateness. RESULTS Malaria was the leading driver of blood demand for anemia among children, accounting for 67% (55,949 units; standard deviation [SD], 1911 units) of projected units requested for children in 2013. Maternal hemorrhage was the leading driver of blood demand for anemia among adults, accounting for 21% (31,321 units; SD, 963 units) of projected units requested. Seventeen percent (26,133 units; SD, 1013 units) of projected requested units were deemed inappropriate. Adults with severe anemia had a mean Hb level of 3.7 g/dL and a mean of 1.6 WB or RBC units per request, resulting in an estimated mean posttransfusion Hb level of 5.3 g/dL. CONCLUSIONS Strategies to prevent and treat underlying causes of anemia and decrease inappropriate blood requests will likely increase blood availability. Restrictive blood ordering practices seen in adults with severe anemia suggests undertreatment of anemia and may result in an underestimation of the national blood demand.

Blood transfusion is a life-saving medical intervention; however, challenges to the recruitment of voluntary, unpaid or otherwise nonremunerated whole blood donors and insufficient funding of national blood services and programs have created obstacles to collecting adequate supplies of safe blood in developing countries (1). Since 2004, the U.S. President's Emergency Plan for AIDS Relief (PEPFAR) has provided approximately $437 million in bilateral financial support to strengthen national blood transfusion services in 14 countries in sub-Saharan Africa and the Caribbean* that have high prevalence rates of human immunodeficiency virus (HIV) infections. CDC analyzed routinely collected surveillance data on annual blood collections and HIV prevalence among donated blood units for 2011-2014. This report updates previous CDC reports (2,3) on progress made by these 14 PEPFAR-supported countries in blood safety, summarizes challenges facing countries as they strive to meet World Health Organization (WHO) targets, and documents progress toward achieving the WHO target of 100% voluntary, nonremunerated blood donors by 2020 (4). During 2011-2014, overall blood collections among the 14 countries increased by 19%; countries with 100% voluntary, nonremunerated blood donations remained stable at eight, and, despite high national HIV prevalence rates, 12 of 14 countries reported an overall decrease in donated blood units that tested positive for HIV. Achieving safe and adequate national blood supplies remains a public health priority for WHO and countries worldwide. Continued success in improving blood safety and achieving WHO targets for blood quality and adequacy will depend on national government commitments to national blood transfusion services or blood programs through increased public financing and diversified funding mechanisms for transfusion-related activities.

Objective—To describe the epizootiological investigation of an outbreak of Q fever (Coxiella burnetii infection). Design—Epidemiological study. Animals—17 goat herds in Washington, Montana, and Oregon. Procedures—In April 2011, an abortion storm at a commercial goat farm in Washington was determined to be caused by C burnetii. A joint epidemiological investigation by public health and veterinary professionals was subsequently performed to assess the extent of the outbreak by performing a trace-forward of goats sold from the index farm, to determine risk factors associated with infection, and to implement control measures. A herd management plan was developed to control the outbreak and reduce risk of human exposure. Quarantine and temporary holds preventing the sale or movement of goats allowed time for trace-forward investigation, education of farmers regarding disease risk, and testing to determine the scope of the outbreak. Results—17 farms were affected; 21 human Q fever cases were identified. Bacterial shedding in feces, vaginal fluid, or milk was confirmed in 156 of 629 (25%) goats tested by PCR assay. Seroprevalence of antibodies against C burnetii in goats, determined by ELISA, was 12%. The risk for C burnetii infection in goats was highest among females, those on farms associated with human Q fever, and those on Washington farms. A protective effect was observed for goats at farms where the primary form of goat carcass disposal was burial. Conclusions and Clinical Relevance—This outbreak illustrated the importance of a joint investigation for zoonotic pathogens and the need to expand and strengthen relationships between medical, public health, and veterinary partners. Heightened awareness and enhanced veterinary diagnostic capabilities for C burnetii are needed to identify and control outbreaks expediently.

Background The January 2010 Haiti earthquake destroyed the National Blood Transfusion Center and reduced monthly national blood collections by > 46%. Efforts to rapidly scale-up blood collections outside of the earthquake-affected region were investigated. Study Design and Methods Blood collection data for 2004–2014 from Haiti's 10 administrative departments were grouped into four regions: Northern, Central, Port-au-Prince and Southern. Analyses compared regional collection totals during the study period. Results Collections in Port-au-Prince accounted for 52% of Haiti's blood supply in 2009, but fell 96% in February 2010. Haiti subsequently increased blood collections in the North, Central and Southern regions to compensate. By May 2010, national blood collections were only 10·9% lower than in May 2009, with 70% of collections coming from outside of Port-au-Prince. By 2013 national collections (27 478 units) had surpassed 2009 levels by 30%, and Port-au-Prince collections had recovered (from 11 074 units in 2009 to 11 670 units in 2013). Conclusion Haiti's National Blood Safety Program managed a rapid expansion of collections outside of Port-au-Prince following the earthquake. Annual collections exceeded pre-earthquake levels by 2012 and continued rising annually. Increased regional collections provided a greater share of the national blood supply, reducing dependence on Port-au-Prince for collections.

Resource-limited countries in Africa experience blood shortages. Understanding clinical drivers of blood demand can inform strategies to increase blood availability.From a national representative sample of 42 hospitals in Tanzania, patient records and requests for whole blood (WB) and red blood cells (RBCs) to treat anemia were analyzed using data collected prospectively from June through September 2013. Abstracted data included cause of anemia, number of requested units, clinical signs, and pretransfusion hemoglobin (Hb) levels. Weighted projections of nationwide drivers of blood demand for the year, 2013, were calculated. Mean posttransfusion Hb levels were estimated, and blood requests were assessed for clinical appropriateness.Malaria was the leading driver of blood demand for anemia among children, accounting for 67% (55,949 units; standard deviation [SD], 1911 units) of projected units requested for children in 2013. Maternal hemorrhage was the leading driver of blood demand for anemia among adults, accounting for 21% (31,321 units; SD, 963 units) of projected units requested. Seventeen percent (26,133 units; SD, 1013 units) of projected requested units were deemed inappropriate. Adults with severe anemia had a mean Hb level of 3.7 g/dL and a mean of 1.6 WB or RBC units per request, resulting in an estimated mean posttransfusion Hb level of 5.3 g/dL.Strategies to prevent and treat underlying causes of anemia and decrease inappropriate blood requests will likely increase blood availability. Restrictive blood ordering practices seen in adults with severe anemia suggests undertreatment of anemia and may result in an underestimation of the national blood demand.

We studied departures from regulatory requirements identified on US Federal Select Agent Program (FSAP) inspections to increase transparency regarding biosafety and security risk at FSAP-regulated entities and identify areas for programmatic improvement. Regulatory departures from inspections led by Centers for Disease Control and Prevention inspectors during 2014-15 were grouped into "biosafety," "security," and "other" observation categories and assigned a risk level and score reflecting perceived severity. The resulting 2,267 biosafety (n = 1,153) and security (n = 1,114) observations from 296 inspections were analyzed by frequency and risk across entity and inspection characteristics. The greatest proportion of biosafety observations involved equipment and facilities (28%), and the greatest proportion of security observations involved access restrictions (33%). The greatest proportion of higher-risk observations for biosafety were containment issues and for security were inventory discrepancies. Commercial entities had the highest median cumulative risk score per inspection (17), followed by private (13), academic (10), federal government (10), and nonfederal government (8). Maximum containment (BSL-4) inspections had higher median biosafety risk per inspection (13) than other inspections (5) and lower security risk (0 vs 4). Unannounced inspections had proportionally more upper risk level observations than announced (biosafety, 21% vs 12%; security, 18% vs 7%). Possessors of select agents had higher median biosafety risk per inspection (6) than nonpossessors (4) and more upper risk level security observations (10% vs 0%). Programmatic changes to balance resources according to entity risk may strengthen FSAP oversight. Varying inspection methods by select agent possession and entity type, and conducting more unannounced inspections, may be beneficial.

Q fever is a zoonotic disease caused by inhalation of the bacterium Coxiella burnetii . Ruminant livestock are common reservoirs for C. burnetii , and bacteria present in aerosols derived from the waste of infected animals can infect humans. The significance of infection from material deposited in the environment versus transmission directly from infected animals is not known. In 2011, an outbreak of Q fever cases on farms in Washington and Montana was associated with infected goats. A study was undertaken to investigate the quantity and spatial distribution of C. burnetii in the environment of these goat farms. Soil, vacuum, and sponge samples collected on seven farms epidemiologically linked to the outbreak were tested for the presence of C. burnetii DNA by quantitative PCR. Overall, 70.1% of the samples were positive for C. burnetii . All farms had positive samples, but the quantity of C. burnetii varied widely between samples and between farms. High quantities of C. burnetii DNA were in goat housing/birthing areas, and only small quantities were found in samples collected more than 50 m from these areas. Follow-up sampling at one of the farms 1 year after the outbreak found small quantities of C. burnetii DNA in air samples and large quantities of C. burnetii persisting in soil and vacuum samples. The results suggest that the highest concentrations of environmental C. burnetii are found in goat birthing areas and that contamination of other areas is mostly associated with human movement.

Investigations into the evolutionary history of the common chimpanzee, Pan troglodytes, have produced inconsistent results due to differences in the types of molecular data considered, the model assumptions employed, and the quantity and geographical range of samples used. We amplified and sequenced 24 complete P. troglodytes mitochondrial genomes from fecal samples collected at multiple study sites throughout sub-Saharan Africa. Using a "relaxed molecular clock," fossil calibrations, and 12 additional complete primate mitochondrial genomes, we analyzed the pattern and timing of primate diversification in a Bayesian framework. Our results support the recognition of four chimpanzee subspecies. Within P. troglodytes, we report a mean (95% highest posterior density [HPD]) time since most recent common ancestor (tMRCA) of 1.026 (0.811-1.263) Ma for the four proposed subspecies, with two major lineages. One of these lineages (tMRCA = 0.510 [0.387-0.650] Ma) contains P. t. verus (tMRCA = 0.155 [0.101-0.213] Ma) and P. t. ellioti (formerly P. t. vellerosus; tMRCA = 0.157 [0.102-0.215] Ma), both of which are monophyletic. The other major lineage contains P. t. schweinfurthii (tMRCA = 0.111 [0.077-0.146] Ma), a monophyletic clade nested within the P. t. troglodytes lineage (tMRCA = 0.380 [0.296-0.476] Ma). We utilized two analysis techniques that may be of widespread interest. First, we implemented a Yule speciation prior across the entire primate tree with separate coalescent priors on each of the chimpanzee subspecies. The validity of this approach was confirmed by estimates based on more traditional techniques. We also suggest that accurate tMRCA estimates from large computationally difficult sequence alignments may be obtained by implementing our novel method of bootstrapping smaller randomly subsampled alignments.

Viral pathogens play a prominent role in human health owing to their ability to rapidly evolve creative new ways to exploit their hosts. As elegant and deceptive as many viral adaptations are, humans and their ancestors have repeatedly answered their call with equally impressive adaptations. Here we argue that the coevolutionary arms race between humans and their viral pathogens is one of the most important forces in human molecular evolution, past and present. With a focus on HIV-1 and other RNA viruses, we highlight recent developments in our understanding of the human innate and adaptive immune systems and how the selective pressures exerted by viruses have shaped the human genome. We also discuss how the antiviral function of cellular machinery like RNAi and APOBEC3G blur the lines between innate and adaptive immunity. The remarkable power of natural selection is revealed in each host-pathogen arms race examined.

Contrary to early predictions of sperm competition theory, postcopulatory sexual selection favoring increased investment per sperm (e.g., sperm size, sperm quality) has been demonstrated in numerous organisms. We empirically demonstrate for Drosophila melanogaster that both sperm quality and sperm quantity independently contribute to competitive male fertilization success. In addition to these independent effects, there was a significant interaction between sperm quality and quantity that suggests an internal positive reinforcement on selection for sperm quality, with selection predicted to intensify as investment per sperm increases and the number of sperm competing declines. The mechanism underlying the sperm quality advantage is elucidated through examination of the relationship between female sperm-storage organ morphology and the differential organization of different length sperm within the organ. Our results exemplify that primary sex cells can bear secondary sexual straits.

Infections with hepatitis B virus (HBV) and hepatitis C virus (HCV) are major causes of morbidity and mortality globally, primarily because of sequelae of chronic liver disease including cirrhosis and hepatocellular carcinoma. The risks for HBV and HCV transmission via blood transfusions have been described previously and are believed to be higher in countries in sub-Saharan Africa. Reducing the risk for transfusion-transmitted human immunodeficiency virus (HIV), HBV, and HCV infection is a priority for international aid organizations, such as the U.S. President's Emergency Plan for AIDS Relief (PEPFAR), the Global Fund to Combat HIV/AIDS, Malaria, and Tuberculosis, and the World Health Organization (WHO). Over the last decade, PEPFAR and the Global Fund have supported blood safety programs in many sub-Saharan African countries with heavy burdens of HIV and acquired immunodeficiency syndrome (AIDS), hepatitis, malaria, and maternal mortality. This report summarizes HBV- and HCV-related surveillance data reported by the blood transfusion services of WHO member states to WHO's Global Database on Blood Safety (GDBS) (4). It also evaluates the performance of blood safety programs in screening for HBV and HCV in 38 sub-Saharan Africa countries. Selected GDBS indicators were compared for the years 2000 and 2004 (referred to as the 2000/2004 period) and 2010 and 2011 (referred to as the 2010/2011 period). From 2000/2004 to 2010/2011, the median of the annual number of units donated per country increased, the number of countries screening at least 95% of blood donations for HBV and HCV increased, and the median of the national prevalence of HBV and HCV marker-reactive blood donations decreased. These findings suggest that during the past decade, more blood has been donated and screened for HBV and HCV, resulting in a safer blood supply. Investments in blood safety should be continued to further increase the availability and safety of blood products in sub-Saharan Africa.

Sperm have traditionally been regarded as energetically cheap and effectively limitless in supply, although evidence conflicting with this view has become increasingly abundant. For instance, males from a variety of taxa have been shown to strategically partition sperm across ejaculates in response to perceived sperm competition risk. It follows that males might also be predicted to adaptively modulate the rate at which sperm are produced. Here we show that, in the giant sperm producing fruitfly Drosophila bifurca , solitary males with infrequent access to females produce sperm at a much lower rate than males raised in association with females and other males. Our results support the prediction that males with little risk of sperm competition risk or few mating opportunities should divert resources away from gamete production.

To examine dog bites among American Indian (AI) and Alaska Native (AN) children visiting Indian Health Service and tribal health facilities.We retrospectively analyzed hospitalizations and outpatient visits with a diagnosis of dog bite between 2001 and 2008 in AI/AN children aged20 years. Rates of dog bite hospitalizations and outpatient visits were estimated by age group, sex, region, and number and location of open wounds using Indian Health Service data. Analyses of hospitalizations for the general US population aged20 years used the Nationwide Inpatient Sample.The average annual dog bite hospitalization rate was higher among AI/AN children in Alaska (6.1/100,000 population) and the Southwest region (5.3/100,000) compared with the general US child population (3.1/100,000; 95% CI, 2.9-3.3/100,000). The average annual outpatient visit rate in AI/AN children was highest in the Alaska (596.4/100,000), Southwest (540.0/100,000), and Northern Plains West (537.6/100,000) regions. The hospitalization rate was highest in both AI/AN and US males aged5 years, and outpatient visit rates were highest in AI/AN males aged 5-9 years. Open wounds diagnoses were most commonly seen on the head, neck, and face in hospitalized children (45.5% of open wounds in AI/AN children, 59.3% in US children; SE, 1.0%) and on the leg in AI/AN outpatients (35.6%).Dog bites represent a significant public health threat in AI/AN children in the Alaska, the Southwest, and Northern Plains West regions of the US. Enhanced animal control and education efforts should reduce dog bite injuries and associated problems with pets and stray dogs, such as emerging infectious diseases.

Rocky Mountain spotted fever, a tick-borne disease caused by Rickettsia rickettsii, is challenging to diagnose and rapidly fatal if not treated. We describe a decedent who was co-infected with group A β-hemolytic streptococcus and R. rickettsii. Fatal cases of Rocky Mountain spotted fever may be underreported because they present as difficult to diagnose co-infections.

Because a constant rate of DNA sequence evolution cannot be assumed to be ubiquitous, relaxed molecular clock inference models have proven useful when estimating rates and divergence dates. Furthermore, it has been recently suggested that using relaxed molecular clocks may provide superior accuracy and precision in phylogenetic inference compared with traditional time-free methods that do not incorporate a molecular clock. We perform a simulation study to determine if assuming a relaxed molecular clock does indeed improve the quality of phylogenetic inference. We analyze sequence data simulated under various rate distributions using relaxed-clocks, strict-clocks, and time-free Bayesian phylogenetic inference models. Our results indicate that no difference exists in the quality of phylogenetic inference between assuming a relaxed molecular clock and making no assumption about the clock-likeness of sequence evolution. This pattern is likely due to the bias-variance trade-off inherent in this type of phylogenetic inference. We also compared the quality of inference between Bayesian and maximum likelihood time-free inference models and found them to be qualitatively similar.

Postcopulatory sexual selection favours males which are strong offensive and defensive sperm competitors. As a means of identifying component traits comprising each strategy, we used an experimental evolution approach. Separate populations ofDrosophila melanogasterwere selected for enhanced sperm offence and defence. Despite using a large outbred population and evidence of substantive genetic variation for each strategy, neither trait responded to selection in the two replicates of this experiment. Recent work with fixed chromosome lines ofD. melanogastersuggests that complex genotypic interactions between females and competing males contribute to the maintenance of this variation. To determine whether such interactions could explain our lack of response to selection on sperm offence and defence, we quantified sperm precedence across multiple sperm competition bouts using an outbredD. melanogasterpopulation exhibiting continuous genetic variation. Both offensive and defensive sperm competitive abilities were found to be significantly repeatable only across matings involving ejaculates of the same pair of males competing within the same female. These repeatabilities decreased when the rival male stayed the same but the female changed, and they disappeared when both the rival male and the female changed. Our results are discussed with a focus on the complex nature of sperm precedence and the maintenance of genetic variation in ejaculate characteristics.

Contrary to early predictions of sperm competition theory, postcopulatory sexual selection favoring increased investment per sperm (e.g., sperm size, sperm quality) has been demonstrated in numerous organisms. We empirically demonstrate for Drosophila melanogaster that both sperm quality and sperm quantity independently contribute to competitive male fertilization success. In addition to these independent effects, there was a significant interaction between sperm quality and quantity that suggests an internal positive reinforcement on selection for sperm quality, with selection predicted to intensify as investment per sperm increases and the number of sperm competing declines. The mechanism underlying the sperm quality advantage is elucidated through examination of the relationship between female sperm-storage organ morphology and the differential organization of different length sperm within the organ. Our results exemplify that primary sex cells can bear secondary sexual straits.

Research into the evolution of giant sperm has uncovered a paradox within the foundations of sexual selection theory. Post- copulatory sexual selection on males (that is, sperm competition and cryptic female choice) can lead to decreased sperm numbers by favouring the production of larger sperm1. However, a decline in sperm numbers is predicted to weaken selection on males and increase selection on females2,3. As isogamy is approached (that is, as investment per gamete by males approaches that by females), sperm become less abundant, ova become relatively less rare, and competition between males for fertilization success is predicted to weaken. Sexual selection for longer sperm, therefore, is expected to be self limiting. Here we examine this paradox in Drosophila along the anisogamy–isogamy continuum using intraspecific experimental evolution techniques and interspecific comparative techniques. Our results confirm the big-sperm paradox by show- ing that the sex difference in sexual selection gradients4 decreases as sperm size increases. However, a resolution to the paradox is provided when this finding is interpreted in concert with the 'opportunity for selection' and the 'opportunity for sexual selec- tion'5,6. Furthermore, we show that most of the variation in measures of selection intensity is explained by sperm length and relative investment in sperm production.

Understanding the evolution of polyandry (mating with multiple males) is a major issue in the study of animal breeding systems. We examined the adaptive significance of polyandry in Drosophila melanogaster, a species with well-documented costs of mating in which males generally cannot force copulations. We found no direct fitness advantages of polyandry. Females that mated with multiple males had no greater mean fitness and no different variance in fitness than females that mated repeatedly with the same male. Subcomponents of reproductive success, including fecundity, egg hatch rate, larval viability, and larval development time, also did not differ between polyandrous and monogamous females. Polyandry had no affect on progeny sex ratios, suggesting that polyandry does not function against costly sex-ratio distorters. We also found no evidence that polyandry functions to favor the paternity of males successful in precopulatory sexual selection. Experimentally controlled opportunities for precopulatory sexual selection had no effect on postcopulatory sperm precedence. Although these results were generally negative, they are supported with substantial statistical power and they help narrow the list of evolutionary explanations for polyandry in an important model species.

As of July 1, 2015, Guinea, Liberia, and Sierra Leone have reported a total of 27,443 confirmed, probable, and suspected Ebola virus disease (Ebola) cases and 11,220 deaths. Guinea and Sierra Leone have yet to interrupt transmission of Ebola virus. In January, 2016, Liberia successfully achieved Ebola transmission-free status, with no new Ebola cases occurring during a 42-day period; however, new Ebola cases were reported beginning June 29, 2015. Local cultural practices and beliefs have posed challenges to disease control, and therefore, targeted, timely health messages are needed to address practices and misperceptions that might hinder efforts to stop the spread of Ebola. As early as September 2014, Ebola spread to most counties in Liberia. To assess Ebola-related knowledge, attitudes, and practices (KAP) in the community, CDC epidemiologists who were deployed to the counties (field team), carried out a survey conducted by local trained interviewers. The survey was conducted in September and October 2014 in five counties in Liberia with varying cumulative incidence of Ebola cases. Survey results indicated several findings. First, basic awareness of Ebola was high across all surveyed populations (median correct responses = 16 of 17 questions on knowledge of Ebola transmission; range = 2-17). Second, knowledge and understanding of Ebola symptoms were incomplete (e.g., 61% of respondents said they would know if they had Ebola symptoms). Finally, certain fears about the disease were present:90% of respondents indicated a fear of Ebola patients,40% a fear of cured patients, and50% a fear of treatment units (expressions of this last fear were greater in counties with lower Ebola incidence). This survey, which was conducted at a time when case counts were rapidly increasing in Liberia, indicated limited knowledge of Ebola symptoms and widespread fear of Ebola treatment units despite awareness of communication messages. Continued efforts are needed to address cultural practices and beliefs to interrupt Ebola transmission.