ABSTRACT
Mycobacterium abscessus infections have been reported as adverse events related to medical tourism. We report M. abscessus meningitis in a patient who traveled from Colorado, USA, to Mexico to receive intrathecal stem cell injections as treatment for multiple sclerosis. We also review the management of this challenging central nervous system infection.
Subject(s)
Medical Tourism , Meningitis , Mycobacterium Infections, Nontuberculous , Mycobacterium abscessus , Humans , Meningitis/drug therapy , Mycobacterium abscessus/physiology , Mycobacterium Infections, Nontuberculous/diagnosis , Mycobacterium Infections, Nontuberculous/etiology , Mycobacterium Infections, Nontuberculous/drug therapy , Stem CellsABSTRACT
Following the establishment of the Infectious Diseases Society of America (IDSA), women played a minor role as IDSA leaders, awards recipients, and presenters at the national meeting. Since the formation of the IDSA Women's Committee in 1992, women have played an increasing role in all of these domains of the Society. Two subsequent IDSA task forces have emphasized the importance of women, and other unrepresented minorities, to the success of the core missions of the Society. Ongoing efforts to maintain the presence of women and their unique talents, experiences, and understandings in the Society will sustain the strengths of IDSA.
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Communicable Diseases/history , Physicians, Women/history , Awards and Prizes , Female , History, 20th Century , History, 21st Century , Humans , Leadership , Minority Groups , Physicians, Women/organization & administration , Societies, Medical/historySubject(s)
Asthma/epidemiology , COVID-19/epidemiology , Hospitalization/statistics & numerical data , Adult , Aged , Aged, 80 and over , Body Mass Index , Female , Humans , Intensive Care Units/statistics & numerical data , Intubation, Intratracheal/statistics & numerical data , Logistic Models , Male , Middle Aged , Respiration, Artificial/statistics & numerical data , Risk Factors , Young AdultABSTRACT
The novel coronavirus disease (COVID-19) pandemic has unveiled underlying health inequities throughout the United States. The pandemic has spread across U.S. states, affecting different vulnerable populations, including both inner-city and rural populations, and those living in congregate settings such as nursing homes and assisted-living facilities. In addition, since early April, there has been an increasing number of outbreaks of COVID-19 in jails and prisons. We describe three overlapping epidemiologic waves of spread of COVID-19 linked to three different kinds of structural vulnerabilities.
Subject(s)
Coronavirus Infections/epidemiology , Coronavirus Infections/transmission , Pneumonia, Viral/epidemiology , Pneumonia, Viral/transmission , Vulnerable Populations , Aged , Betacoronavirus , COVID-19 , Crowding , Frail Elderly , Humans , Nursing Homes , Occupational Exposure , Pandemics , Prisons , Rural Population , SARS-CoV-2 , United States/epidemiology , Urban PopulationABSTRACT
Problem: Although scholarship during residency training is an important requirement from the Accreditation Council for Graduate Medical Education, efforts to support resident scholarship have demonstrated inconsistent effects and have not comprehensively evaluated resident experiences. Intervention: We developed the Leadership and Discovery Program (LEAD) to facilitate scholarship among all non-research-track categorical internal medicine (IM) residents. This multifaceted program set expectations for all residents to participate in a scholarly project, supported faculty to manage the program, facilitated access to faculty mentors, established a local resident research day to highlight scholarship, and developed a didactic lecture series. Context: We implemented LEAD at a large university training program. We assessed resident scholarship before and after LEAD implementation using objective metrics of academic productivity (i.e., scientific presentations, peer-reviewed publications, and both presentations and publications). We compared these metrics in LEAD participants and a similar historical group of pre-LEAD controls. We also assessed these outcomes over the same two periods in research track residents who participated in research training independent from and predating LEAD (research track controls and pre-LEAD research track controls). We conducted focus groups to qualitatively assess resident experiences with LEAD. Outcome: Compared to 63 pre-LEAD controls, greater proportions of 52 LEAD participants completed scientific presentations (48.1% vs. 28.6%, p = .03) and scientific presentations and peer-reviewed publications (23.1% vs. 9.5%, p = .05). No significant differences existed for any academic productivity metrics among research track controls and pre-LEAD research track controls (p > .23, all comparisons). Perceived facilitators of participation in LEAD included residents' desire for research experiences and opportunities to publish prior to fellowship training; the main barrier to participation was feeling overwhelmed due to the time constraints imposed by clinical training. Suggestions for improvement included establishing clearer programmatic expectations and providing lists of potential mentors and projects. Lessons Learned: Implementation of a multifaceted program to support scholarship during residency was associated with significant increases in academic productivity among IM residents. Residents perceived that programs to support scholarship during residency training should outline clear expectations and identify available mentors and projects for residents who are challenged by the time constraints of clinical training.
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Education, Medical, Graduate/organization & administration , Fellowships and Scholarships/organization & administration , Internship and Residency/organization & administration , Leadership , Quality Improvement , Biomedical Research/statistics & numerical data , Efficiency , Humans , Program Evaluation , Schools, MedicalABSTRACT
PROBLEM: Traditionally, internal medicine continuity clinic consists of a half day per week, regardless of rotation, which may create conflict with ongoing inpatient responsibilities. A 50/50 block schedule, which alternates inpatient and outpatient rotations and concentrates continuity clinic during outpatient rotations, minimizes conflicting responsibilities. However, its impact on patient care has not been widely studied. Continuity is a concern, and intervisit continuity in particular has not been evaluated. INTERVENTION: We implemented a 50/50 block model with "clinic buddy" system to optimize continuity and assessed outcomes pre- and postintervention. Residents alternated inpatient and elective blocks, with clinic 1 full day per week on elective blocks only. Resident and preceptor perceptions were measured using 5-point Likert surveys to evaluate impact on clinic experience and workload. The authors calculated visit and intervisit continuity using a Usual Provider of Care index and measured blood pressure and hemoglobin A1c as quality markers to evaluate the impact on continuity and quality of care. CONTEXT: Participants were 208 medicine residents and 39 core faculty members at 3 University of Pittsburgh Medical Center clinics. The intervention was implemented in June 2014. OUTCOME: In the 50/50 system, inpatient distractions decreased (3.59 vs. 1.71, p < .001). Residents more strongly agreed that there was adequate time for conferences (3.33 vs. 4.05), they worked well within the system to achieve best patient care (3.13 vs. 3.61), and multidisciplinary teams worked well together (3.51 vs. 4.08) (all p < .001). Intervisit continuity was unchanged (73%, both models, p = .79). Visit continuity decreased (67.2% vs. 63.7%, p < .001). Blood pressure and hemoglobin A1c were unchanged. LESSONS LEARNED: This 50/50 model minimized inpatient distractions in clinic and increased perceived time for learning. Residents reported improved sense of patient ownership, relations within the multidisciplinary team, and integration into the clinic system. Intervisit continuity was preserved, visit continuity was slightly decreased, and patient outcomes were not impacted in this model.
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Continuity of Patient Care , Faculty, Medical/psychology , Internal Medicine/education , Preceptorship/organization & administration , Health Knowledge, Attitudes, Practice , Humans , Pennsylvania , Surveys and Questionnaires , Treatment OutcomeABSTRACT
Students attending schools play an important role in the transmission of influenza. In this study, we present a social network analysis of contacts among 1,828 students in eight different schools in urban and suburban areas in and near Pittsburgh, Pennsylvania, United States of America, including elementary, elementary-middle, middle, and high schools. We collected social contact information of students who wore wireless sensor devices that regularly recorded other devices if they are within a distance of 3 meters. We analyzed these networks to identify patterns of proximal student interactions in different classes and grades, to describe community structure within the schools, and to assess the impact of the physical environment of schools on proximal contacts. In the elementary and middle schools, we observed a high number of intra-grade and intra-classroom contacts and a relatively low number of inter-grade contacts. However, in high schools, contact networks were well connected and mixed across grades. High modularity of lower grades suggests that assumptions of homogeneous mixing in epidemic models may be inappropriate; whereas lower modularity in high schools suggests that homogenous mixing assumptions may be more acceptable in these settings. The results suggest that interventions targeting subsets of classrooms may work better in elementary schools than high schools. Our work presents quantitative measures of age-specific, school-based contacts that can be used as the basis for constructing models of the transmission of infections in schools.
Subject(s)
Schools , Social Support , Students/psychology , Humans , PennsylvaniaABSTRACT
PURPOSE: Since implementation of resident duty-hour restrictions, many academic medical centers utilize night-float teams to admit patients during off hours. Patients are transferred to other resident physicians the subsequent morning as "hold-over admissions." Despite the increase of hold-over admissions, there are limited data on resident perceptions of their educational value. This study investigated resident perceptions of hold-over admissions, and whether they approach hold-over admissions differently than new admissions. METHOD: Survey of internal medicine residents at an academic medical center. RESULTS: A total of 111 residents responded with a response rate of 71 %. Residents reported spending 56.2 min (standard deviation [SD] 18.9) compared to 80.0 min (SD 25.8) admitting new patients (p < 0.01). Residents reported spending significantly (p < 0.01) less time reviewing the medical record, performing histories, examining patients, devising care plans and writing orders in hold-over admissions compared to new admissions. Residents had neutral views on the educational value of hold-over admissions. Features that significantly (p < 0.01) increased the educational value of admissions included severe illness, patient complexity, and being able to write the initial patient care orders. Residents estimated 42.5 % (SD 14) of their admissions were hold-over patients. CONCLUSIONS: Residents spend less time in all aspects of admitting hold-over patients. Despite less time spent admitting hold-over patients, residents had neutral views on the educational value of such admissions.
Subject(s)
Internal Medicine/education , Internal Medicine/methods , Internship and Residency/methods , Patient Admission , Personnel Staffing and Scheduling , Work Schedule Tolerance , Adult , Data Collection/methods , Female , Humans , Internal Medicine/trends , Internship and Residency/trends , Male , Patient Admission/trends , Personnel Staffing and Scheduling/trendsABSTRACT
BACKGROUND: Despite agreement that handwashing decreases hospital-acquired infections (HAIs), physician hand hygiene remains suboptimal. Interventions to empower patients to discuss handwashing have had variable success. OBJECTIVE: To understand patient perceived barriers to discussing physician hand hygiene and to determine whether patients prefer electronic alerts over printed information as an intervention to discuss physician handwashing. DESIGN: Cross-sectional study of 250 medical/surgical patients at an academic medical center. RESULTS: Ninety-six percent of patients had heard of HAIs. Ninety-six percent of patients thought it was important for physicians to clean their hands before touching anything in a patient's room. The majority of patients (78%) believed patients should remind physicians to clean their hands. Thirty-two percent of patients observed physician hand hygiene noncompliance. In multivariate analysis, predictors of not speaking up regarding physician hand hygiene included never having worked in health care (odds ratio [OR], 2.8 [95% confidence interval (CI), 1.5-5.1]), not observing a physician clean hands before touching the patient (OR, 2.4 [95% CI, 1.3-4.4]), and not thinking patients should have to remind physicians to clean hands (OR, 5.5 [95% CI, 2.4-12.7]). Ninety-three percent of patients favored electronic device reminders over printed information as an intervention to encourage patients to discuss hand hygiene with their doctors. CONCLUSIONS: The strongest predictor of not challenging a doctor to clean their hands was not believing it was the patient's role to do so. Patients prefer electronic device reminders to printed information as an aid in overcoming barriers to discussing hand hygiene with physicians.
Subject(s)
Hand Hygiene/methods , Patient Preference , Patients/psychology , Physician-Patient Relations , Adolescent , Adult , Aged , Aged, 80 and over , Attitude to Health , Cross-Sectional Studies , Female , Hand Hygiene/standards , Humans , Male , Middle Aged , Physicians/psychology , Physicians/standards , Power, Psychological , Young AdultABSTRACT
BACKGROUND: Limitations of the current annual influenza vaccine have led to ongoing efforts to develop a 'universal' influenza vaccine, i.e., one that targets a ubiquitous portion of the influenza virus so that the coverage of a single vaccination can persist for multiple years. OBJECTIVES: To estimate the economic value of a 'universal' influenza vaccine compared to the standard annual influenza vaccine, starting vaccination in the pediatric population (2-18 year olds), over the course of their lifetime. PATIENT/METHODS: Monte Carlo decision analytic computer simulation model. RESULTS: Universal vaccine dominates (i.e., less costly and more effective) the annual vaccine when the universal vaccine cost ≤ $100/dose and efficacy ≥ 75% for both the 5- and 10-year duration. The universal vaccine is also dominant when efficacy is ≥ 50% and protects for 10 years. A $200 universal vaccine was only cost-effective when ≥ 75% efficacious for a 5-year duration when annual compliance was 25% and for a 10-year duration for all annual compliance rates. A universal vaccine is not cost-effective when it cost $200 and when its efficacy is ≤ 50%. The cost-effectiveness of the universal vaccine increases with the duration of protection. CONCLUSIONS: Although development of a universal vaccine requires surmounting scientific hurdles, our results delineate the circumstances under which such a vaccine would be a cost-effective alternative to the annual influenza vaccine.
Subject(s)
Influenza Vaccines/economics , Influenza, Human/economics , Adolescent , Adult , Aged , Child , Child, Preschool , Cost-Benefit Analysis , Female , Humans , Influenza Vaccines/administration & dosage , Influenza, Human/prevention & control , Male , Middle Aged , Monte Carlo Method , Vaccination/economics , Young AdultABSTRACT
Host genetic factors that modify risk of pneumococcal disease may help target future public health interventions to individuals at highest risk of disease. We linked data from population-based surveillance for invasive pneumococcal disease (IPD) with state-based newborn dried bloodspot repositories to identify biological samples from individuals who developed invasive pneumococcal disease. Genomic DNA was extracted from 366 case and 732 anonymous control samples. TagSNPs were selected in 34 candidate genes thought to be associated with host response to invasive pneumococcal disease, and a total of 326 variants were successfully genotyped. Among 543 European Americans (EA) (182 cases and 361 controls), and 166 African Americans (AA) (53 cases and 113 controls), common variants in surfactant protein D (SFTPD) are consistently underrepresented in IPD. SFTPD variants with the strongest association for IPD are intronic rs17886286 (allelic OR 0.45, 95% confidence interval (CI) [0.25, 0.82], with pâ=â0.007) in EA and 5' flanking rs12219080 (allelic OR 0.32, 95%CI [0.13, 0.78], with pâ=â0.009) in AA. Variants in CD46 and IL1R1 are also associated with IPD in both EA and AA, but with effects in different directions; FAS, IL1B, IL4, IL10, IL12B, SFTPA1, SFTPB, and PTAFR variants are associated (p≤0.05) with IPD in EA or AA. We conclude that variants in SFTPD may protect against IPD in EA and AA and genetic variation in other host response pathways may also contribute to risk of IPD. While our associations are not corrected for multiple comparisons and therefore must be replicated in additional cohorts, this pilot study underscores the feasibility of integrating public health surveillance with existing, prospectively collected, newborn dried blood spot repositories to identify host genetic factors associated with infectious diseases.
Subject(s)
Genetic Predisposition to Disease/genetics , Pneumococcal Infections/genetics , Polymorphism, Single Nucleotide , Population Surveillance/methods , Black or African American/genetics , Child, Preschool , Cohort Studies , DNA/analysis , DNA/blood , Female , Gene Frequency , Genotype , Host-Pathogen Interactions , Humans , Infant , Infant, Newborn , Male , Membrane Cofactor Protein/genetics , Pilot Projects , Pneumococcal Infections/ethnology , Pneumococcal Infections/microbiology , Pulmonary Surfactant-Associated Protein D/genetics , Receptors, Interleukin-1 Type I/genetics , Risk Factors , Streptococcus pneumoniae/physiology , White People/geneticsABSTRACT
When influenza vaccines are in short supply, allocating vaccines equitably among different jurisdictions can be challenging. But justice is not the only reason to ensure that poorer counties have the same access to influenza vaccines as do wealthier ones. Using a detailed computer simulation model of the Washington, D.C., metropolitan region, we found that limiting or delaying vaccination of residents of poorer counties could raise the total number of influenza infections and the number of new infections per day at the peak of an epidemic throughout the region-even in the wealthier counties that had received more timely and abundant vaccine access. Among other underlying reasons, poorer counties tend to have high-density populations and more children and other higher-risk people per household, resulting in more interactions and both increased transmission of influenza and greater risk for worse influenza outcomes. Thus, policy makers across the country, in poor and wealthy areas alike, have an incentive to ensure that poorer residents have equal access to vaccines.
Subject(s)
Health Services Accessibility , Influenza A Virus, H1N1 Subtype/immunology , Influenza Vaccines/supply & distribution , Influenza, Human/prevention & control , Poverty Areas , Computer Simulation , District of Columbia , Humans , Immunization Programs/statistics & numerical data , Influenza, Human/virology , Socioeconomic FactorsABSTRACT
OBJECTIVES: To develop 3 computer simulation models to determine the potential economic effect of using intravenous (IV) antiviral agents to treat hospitalized patients with influenza-like illness, as well as different testing and treatment strategies. STUDY DESIGN: Stochastic decision analytic computer simulation model. METHODS: During the 2009 influenza A(H1N1) pandemic, the Food and Drug Administration granted emergency use authorization of IV neuraminidase inhibitors for hospitalized patients with influenza, creating a need for rapid decision analyses to help guide use. We compared the economic value from the societal and third-party payer perspectives of the following 4 strategies for a patient hospitalized with influenza-like illness and unable to take oral antiviral agents: Strategy 1: Administration of IV antiviral agents without polymerase chain reaction influenza testing. Strategy 2: Initiation of IV antiviral treatment, followed by polymerase chain reaction testing to determine whether the treatment should be continued. Strategy 3: Performance of polymerase chain reaction testing, followed by initiation of IV antiviral treatment if the test results are positive. Strategy 4: Administration of no IV antiviral agents. Sensitivity analyses varied the probability of having influenza (baseline, 10%; range, 10%-30%), IV antiviral efficacy (baseline, oral oseltamivir phosphate; range, 25%-75%), IV antiviral daily cost (range, $20-$1000), IV antiviral reduction of illness duration (baseline, 1 day; range, 1-2 days), and ventilated vs nonventilated status of the patient. RESULTS: When the cost of IV antiviral agents was no more than $500 per day, the incremental cost-effectiveness ratio for most of the IV antiviral treatment strategies was less than $10,000 per quality-adjusted life-year compared with no treatment. When the cost was no more than $100 per day, all 3 IV antiviral strategies were even more cost-effective. The order of cost-effectiveness from most to least was strategies 3, 1, and 2. The findings were robust to changing risk of influenza, influenza mortality, IV antiviral efficacy, IV antiviral daily cost, IV antiviral reduction of illness duration, and ventilated vs nonventilated status of the patient for both societal and third-party payer perspectives. CONCLUSION: Our study supports the use of IV antiviral treatment for hospitalized patients with influenza-like illness.
Subject(s)
Antiviral Agents/therapeutic use , Computer Simulation , Cyclopentanes/therapeutic use , Guanidines/therapeutic use , Influenza A Virus, H1N1 Subtype , Influenza, Human/drug therapy , Models, Economic , Acids, Carbocyclic , Adult , Antiviral Agents/administration & dosage , Antiviral Agents/economics , Confidence Intervals , Cyclopentanes/administration & dosage , Cyclopentanes/economics , Decision Support Techniques , Female , Guanidines/administration & dosage , Guanidines/economics , Health Care Costs , Humans , Influenza, Human/economics , Infusions, Intravenous , Male , Middle Aged , Models, Statistical , Monte Carlo Method , Polymerase Chain Reaction , Quality-Adjusted Life Years , Stochastic Processes , United States , Young AdultABSTRACT
BACKGROUND: Currently more than 340,000 individuals are receiving long-term hemodialysis (HD) therapy for end-stage renal disease and therefore are particularly vulnerable to influenza, prone to more severe influenza outcomes, and less likely to achieve seroprotection from standard influenza vaccines. Influenza vaccine adjuvants, chemical or biologic compounds added to a vaccine to boost the elicited immunologic response, may help overcome this problem. STUDY DESIGN: Economic stochastic decision analytic simulation model. SETTING & PARTICIPANTS: US adult HD population. MODEL, PERSPECTIVE, & TIMEFRAME: The model simulated the decision to use either an adjuvanted or nonadjuvanted vaccine, assumed the societal perspective, and represented a single influenza season, or 1 year. INTERVENTION: Adjuvanted influenza vaccine at different adjuvant costs and efficacies. Sensitivity analyses explored the impact of varying influenza clinical attack rate, influenza hospitalization rate, and influenza-related mortality. OUTCOMES: Incremental cost-effectiveness ratio of adjuvanted influenza vaccine (vs nonadjuvanted) with effectiveness measured in quality-adjusted life-years. RESULTS: Adjuvanted influenza vaccine would be cost-effective (incremental cost-effectiveness ratio <$50,000/quality-adjusted life-year) at a $1 adjuvant cost (on top of the standard vaccine cost) when adjuvant efficacy (in overcoming the difference between influenza vaccine response in HD patients and healthy adults) ≥60% and economically dominant (provides both cost savings and health benefits) when the $1 adjuvant's efficacy is 100%. A $2 adjuvant would be cost-effective if adjuvant efficacy was 100%. LIMITATIONS: All models are simplifications of real life and cannot capture all possible factors and outcomes. CONCLUSIONS: Adjuvanted influenza vaccine with adjuvant cost ≤$2 could be a cost-effective strategy in a standard influenza season depending on the potency of the adjuvant.
Subject(s)
Adjuvants, Immunologic/economics , Influenza Vaccines/economics , Influenza, Human/economics , Renal Dialysis/economics , Adjuvants, Immunologic/therapeutic use , Adult , Aged , Cost-Benefit Analysis , Decision Trees , Female , Humans , Influenza Vaccines/therapeutic use , Influenza, Human/prevention & control , Kidney Failure, Chronic/economics , Kidney Failure, Chronic/therapy , Male , Middle AgedABSTRACT
BACKGROUND: In December 2009, when the H1N1 influenza pandemic appeared to be subsiding, public health officials and unvaccinated individuals faced the question of whether continued H1N1 immunization was still worthwhile. PURPOSE: To delineate what combinations of possible mechanisms could generate a third pandemic wave and then explore whether vaccinating the population at different rates and times would mitigate the wave. METHODS: As part of ongoing work with the Office of the Assistant Secretary for Preparedness and Response at the USDHHS during the H1N1 influenza pandemic, the University of Pittsburgh Models of Infectious Disease Agent Study team employed an agent-based computer simulation model of the Washington DC metropolitan region to delineate what mechanisms could generate a "third pandemic wave" and explored whether vaccinating the population at different rates and times would mitigate the wave. This model included explicit representations of the region's individuals, school systems, workplaces/commutes, households, and communities. RESULTS: Three mechanisms were identified that could cause a third pandemic wave; substantially increased viral transmissibility from seasonal forcing (changing influenza transmission with changing environmental conditions, i.e., seasons) and progressive viral adaptation; an immune escape variant; and changes in social mixing from holiday school closures. Implementing vaccination for these mechanisms, even during the down-slope of the fall epidemic wave, significantly mitigated the third wave. Scenarios showed the gains from initiating vaccination earlier, increasing the speed of vaccination, and prioritizing population subgroups based on Advisory Committee on Immunization Practices recommendations. CONCLUSIONS: Additional waves in an epidemic can be mitigated by vaccination even when an epidemic appears to be waning.
Subject(s)
Disease Outbreaks/prevention & control , Influenza A Virus, H1N1 Subtype/immunology , Influenza Vaccines/administration & dosage , Influenza, Human/prevention & control , Adolescent , Adult , Aged , Child , Child, Preschool , Computer Simulation , Disease Outbreaks/statistics & numerical data , District of Columbia/epidemiology , Humans , Influenza Vaccines/supply & distribution , Influenza, Human/epidemiology , Middle Aged , Models, Biological , Young AdultABSTRACT
BACKGROUND: In April 2009, a new pandemic strain of influenza infected thousands of persons in Mexico and the United States and spread rapidly worldwide. During the ensuing summer months, cases ebbed in the Northern Hemisphere while the Southern Hemisphere experienced a typical influenza season dominated by the novel strain. In the fall, a second wave of pandemic H1N1 swept through the United States, peaking in most parts of the country by mid October and returning to baseline levels by early December. The objective was to determine the seroprevalence of antibodies against the pandemic 2009 H1N1 influenza strain by decade of birth among Pittsburgh-area residents. METHODS AND FINDINGS: Anonymous blood samples were obtained from clinical laboratories and categorized by decade of birth from 1920-2009. Using hemagglutination-inhibition assays, approximately 100 samples per decade (n = 846) were tested from blood samples drawn on hospital and clinic patients in mid-November and early December 2009. Age specific seroprevalences against pandemic H1N1 (A/California/7/2009) were measured and compared to seroprevalences against H1N1 strains that had previously circulated in the population in 2007, 1957, and 1918. (A/Brisbane/59/2007, A/Denver/1/1957, and A/South Carolina/1/1918). Stored serum samples from healthy, young adults from 2008 were used as a control group (n = 100). Seroprevalences against pandemic 2009 H1N1 influenza varied by age group, with children age 10-19 years having the highest seroprevalence (45%), and persons age 70-79 years having the lowest (5%). The baseline seroprevalence among control samples from 18-24 year-olds was 6%. Overall seroprevalence against pandemic H1N1 across all age groups was approximately 21%. CONCLUSIONS: After the peak of the second wave of 2009 H1N1, HAI seroprevalence results suggest that 21% of persons in the Pittsburgh area had become infected and developed immunity. Extrapolating to the entire US population, we estimate that at least 63 million persons became infected in 2009. As was observed among clinical cases, this sero-epidemiological study revealed highest infection rates among school-age children.
Subject(s)
Influenza A Virus, H1N1 Subtype/pathogenicity , Influenza, Human/epidemiology , Seroepidemiologic Studies , Adult , Hemagglutinins/chemistry , Hemagglutinins/classification , Hemagglutinins/genetics , Humans , Influenza, Human/blood , Pennsylvania/epidemiology , Phylogeny , United States/epidemiology , Young AdultABSTRACT
BACKGROUND: Due to the unpredictable burden of pandemic influenza, the best strategy to manage testing, such as rapid or polymerase chain reaction (PCR), and antiviral medications for patients who present with influenza-like illness (ILI) is unknown. METHODOLOGY/PRINCIPAL FINDINGS: We developed a set of computer simulation models to evaluate the potential economic value of seven strategies under seasonal and pandemic influenza conditions: (1) using clinical judgment alone to guide antiviral use, (2) using PCR to determine whether to initiate antivirals, (3) using a rapid (point-of-care) test to determine antiviral use, (4) using a combination of a point-of-care test and clinical judgment, (5) using clinical judgment and confirming the diagnosis with PCR testing, (6) treating all with antivirals, and (7) not treating anyone with antivirals. For healthy younger adults (<65 years old) presenting with ILI in a seasonal influenza scenario, strategies were only cost-effective from the societal perspective. Clinical judgment, followed by PCR and point-of-care testing, was found to be cost-effective given a high influenza probability. Doubling hospitalization risk and mortality (representing either higher risk individuals or more virulent strains) made using clinical judgment to guide antiviral decision-making cost-effective, as well as PCR testing, point-of-care testing, and point-of-care testing used in conjunction with clinical judgment. For older adults (> or = 65 years old), in both seasonal and pandemic influenza scenarios, employing PCR was the most cost-effective option, with the closest competitor being clinical judgment (when judgment accuracy > or = 50%). Point-of-care testing plus clinical judgment was cost-effective with higher probabilities of influenza. Treating all symptomatic ILI patients with antivirals was cost-effective only in older adults. CONCLUSIONS/SIGNIFICANCE: Our study delineated the conditions under which different testing and antiviral strategies may be cost-effective, showing the importance of accuracy, as seen with PCR or highly sensitive clinical judgment.