Optimizing clinical outcomes in polypharmacy through poly-de-prescribing: a longitudinal study.

Objectives: To evaluate polypharmacy in older people to determine whether the number of medications de-prescribed correlates with the extent of improvement in quality of life (QoL) and clinical outcomes. Design: A prospective longitudinal cohort study of polypharmacy in people living in a community in Israel. Setting: Participants aged 65 years or older who took at least six prescription drugs followed up for at least 3 years (range 3-10 years) after poly-de-prescription (PDP) recommendations. Interventions: PDP recommended at first home visit using the Garfinkel algorithm. Annual follow-up and end-of-study questionnaires used to assess clinical outcomes, QoL, and satisfaction from de-prescribing. All medications taken, complications, hospitalizations, and mortality recorded. In total, 307 participants met the inclusion criteria; 25 incomplete end-of-study questionnaires meant 282 participants for subjective analysis. Participants divided into two subgroups: (i) those who discontinued more than 50% of the drugs (PDP group) or (ii) those who discontinued less than 50% of the drugs (non-responders, NR). Main outcome measures: Objective: 3-year survival rate and hospitalizations. Subjective: general satisfaction from de-prescribing; change in functional, mental, and cognitive status; improved sleep quality, appetite, and continence; and decreased pain. Results: Mean age: 83 years (range 65-99 years). Mean number of drugs at baseline visit: 9.8 (range 6-20); 6.7 ± 2.0 de-prescribed in the PDP group (n = 146) and 2.2 ± 2.1 in the NR group (n = 161) (p < 0.001).No statistical difference between the groups in the 3-year survival rate and hospitalizations, but a significant improvement in functional and cognitive status and, in general, satisfaction from the intervention in the PDP group compared to the NR group. Improvement usually evident within the first 3 months and persists for several years. Conclusion: Poly-de-prescribing in the older population has beneficial effects on several clinical outcomes with no detrimental effect on the rate of hospitalization and survival. The extent of improvement correlates with the extent of de-prescribing. Applying the Garfinkel algorithm globally may improve QoL in millions of patients, a clinical and economic win-win situation.

Timing of Lung Transplant Referral in Patients with Severe COVID-19 Lung Injury Supported by ECMO.

Severe respiratory failure caused by COVID-19 often requires mechanical ventilation, including extracorporeal membrane oxygenation (ECMO). In rare cases, lung transplantation (LTx) may be considered as a last resort. However, uncertainties remain about patient selection and optimal timing for referral and listing. This retrospective study analyzed patients with severe COVID-19 who were supported by veno-venous ECMO and listed for LTx between July 2020 and June 2022. Out of the 20 patients in the study population, four who underwent LTx were excluded. The clinical characteristics of the remaining 16 patients were compared, including nine who recovered and seven who died while awaiting LTx. The median duration from hospitalization to listing was 85.5 days, and the median duration on the waitlist was 25.5 days. Younger age was significantly associated with a higher likelihood of recovery without LTx after a median of 59 days on ECMO, compared to those who died at a median of 99 days. In patients with severe COVID-19-induced lung damage supported by ECMO, referral to LTx should be delayed for 8-10 weeks after ECMO initiation, particularly for younger patients who have a higher probability of spontaneous recovery and may not require LTx.

The Use of Rapid COVID-19 Antigen Test in the Emergency Department as a Decision-Support Tool.

The emergency department (ED) is the initial point of contact between hospital staff and patients potentially infected with SARS-CoV-2, thus, prevention of inadvertent exposure to other patients is a top priority. We aimed to assess whether the introduction of antigen-detecting rapid diagnostic tests (Ag-RDTs) to the ED affected the likelihood of unwanted SARS-CoV-2 exposures. In this retrospective single-center study, we compared the rate of unwarranted exposure of uninfected adult ED patients to SARS-CoV-2 during two separate research periods; one before Ag-RDTs were introduced, and one with Ag-RDT used as a decision-support tool. The introduction of Ag-RDTs to the ED significantly decreased the relative risk of SARS-CoV-2-negative patients being incorrectly assigned to the COVID-19 designated site ("red ED"), by 97%. There was no increase in the risk of SARS-CoV-2-positive patients incorrectly assigned to the COVID-19-free site ("green ED"). In addition, duration of ED admission was reduced in both the red and the green ED. Therefore, implementing the Ag-RDT-based triage protocol proved beneficial in preventing potential COVID-19 nosocomial transmission.

Real-World Immunogenicity and Reactogenicity of Two Doses of Pfizer-BioNTech COVID-19 Vaccination in Children Aged 5-11 Years.

There are limited data concerning the immunogenicity and reactogenicity of COVID-19 vaccines in children. A total of 110 children, 5-11 years old were vaccinated with two doses (with a 3-week interval between doses) of the Pfizer-BioNTech COVID-19 vaccine and were followed for 21, 90, and 180 days after vaccination for immunogenicity, adverse events, and breakthrough infections. Ninety days after the first vaccine dose, the GeoMean (CI 95%) of IgG ascended to 1291.0 BAU (929.6-1790.2) for uninfected children and 1670.0 BAU (1131.0-2466.0) for Infected children. One hundred and eighty days after receiving the first dose of the vaccine, the titers decreased to 535.5 BAU (288.4-993.6) for the uninfected children, while only a small decline was detected among infected children-1479.0 (878.2-2490.0). The neutralizing antibodies titer almost did not change over time in the uninfected children, and even elevated for the infected children. Of the 110 vaccinated children, 75.5% were infected, with only mild COVID-19 infection symptoms. Child vaccination was found to be safe, with mild, mostly local, and of short duration, reported AEs. No serious adverse events (SAEs) were reported after vaccination. The durability of two doses of vaccine in children is longer, thus a booster may not be needed as early as in adults.

Poly-De-Prescribing to Treat Polypharmacy: Lowering the Flames of the First Iatrogenic Epidemic.

BACKGROUND: There has been a rapid increase in vulnerable subpopulations of very old with co-morbidity, dementia, frailty, and limited life expectancy. Being treated by many specialists has led to an epidemic of inappropriate medication use and polypharmacy (IMUP) with negative medical and economic consequences. For most medications there are no evidence-based studies in older people and treatments are based on guidelines proven in much younger/healthier populations. OBJECTIVES: To evaluate whether the benefits of reducing IMUP by poly-de-prescribing (PDP) outweighs the negative outcomes in older people with polypharmacy. METHODS: The Garfinkel method and algorithm were used in older people with polypharmacy (≥ 6 prescription drugs). RESULTS: We found that in nursing departments, of 331 drugs de-prescribed only 32 (10%) had to be re-administered. Annual mortality and severe complications requiring referral to acute care facility were significantly reduced in PDP (P < 0.002). In community dwelling older people, successful de-prescribing was achieved in 81% with no increase in adverse events or deaths. Those who de-prescribed ≥ 3 prescription drugs showed significantly more improvement in functional and cognitive status, sleep quality, appetite, serious complications, quality of life, and general satisfaction compared to controls who stopped ≤ 2 medications (P < 0.002). Rates of hospitalization and mortality were comparable. Clinical improvement by polydeprescribing was usually evident within 3 months and persisted for several years. The main barrier to polydeprescribing was physician's unwillingness to deprescribe (P < 0.0001). CONCLUSIONS: Applying the Garfinkel method of PDP may improve the lives of older people and save money.

The effect of the Covid-19 pandemic on patient visits to the emergency department and hospitalizations in medical wards in an Israeli medical center.

BACKGROUND: The Covid-19 pandemic began in Israel on February 2020. Between February and October 2020, 2 periods of lockdown were imposed on Israeli population. OBJECTIVE: To assess the effect of the Covid-19 pandemic on visits to the emergency department (ED) and on hospitalizations in medical wards in Israel's Chaim Sheba Medical Center, and to compare the effect during the first and second lockdowns. METHODS: Data regarding the number of visits of non-Covid-19 patients to the ED and the number of admissions to the medical wards, were extracted from the computerized system of the hospital. Data were analyzed for patients' characteristics, length of stay in the medical wards, in hospital mortality and the rate of 7 and 30 days re-hospitalization, and compared to the same period during 2019. RESULTS: Total visits to the Sheba ED during March-October decreased by 18.5%. The most dramatic decrease occurred during the first lockdown. The number of patients admitted to the Sheba medical wards decreased by 28% (P < 0.05). The length of stay decreased from 3.69 days during 2019 to 3.42 days during 2020 (P < 0.01). The most pronounced decrease in the length of stay was observed during the second month of the first lockdown. During the pandemic, hospitalized patients at Sheba were older and were less likely to be males. The in-hospital absolute non-COVID mortality decreased from 913 to 858 respectively. CONCLUSIONS: The Covid-19 crisis emphasizes the role of medical wards in the care of complex patients. Medical wards in Israel were at the frontline of Israel's battle against this pandemic, while continuing to treat very complex non-Covid patients. To avoid burnout of the medical staff who treat very intensively complex patients, we believe these wards should be strengthen with specialists having expertise in treating these patients. Due to our insights, the Sheba medical Center is now redesigning the concept of how intensive care beds should be managed in a big tertiary center.

Emergency Department Triage in the Era of COVID-19: The Sheba Medical Center Experience.

BACKGROUND: Sheba Medical Center, Tel Hashomer, is a tertiary hospital located in the center of Israel. It is the largest hospital in Israel and was the first to face coronavirus disease-2019 (COVID-19) patients in the country at the beginning of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic. OBJECTIVES: To describe our experience with the COVID-19 pandemic, focusing on our triage method in the emergency department (ED). Our goal was to keep the main hospitalization buildings clean of infection by separating COVID-19 positive patients from COVID-19 negative patients. METHODS: We divided our ED into two separate sections: a regular non-COVID-19 ED and an advanced biological ED. We created clear protocols of triage for suspected and confirmed COVID-19 patients. We reviewed the data of patients admitted to our ED during the month of March and analyzed the results of our triage method in separating COVID-19 positive from negative patients. RESULTS: During the month of March 2020, 7957 patients were referred to our ED. Among them 2004 were referred to the biological ED and 5953 were referred to the regular ED. Of the 2004 patients referred to the biological ED, 1641 (81.8%) were sampled for SARS-CoV-2 polymerase chain reaction of whom 143 (8.7%) were positive. Only two COVID-19 positive patients unintentionally entered the main clean hospital, making our triage almost full proof. CONCLUSIONS: Our triage method was successful in separating COVID-19 positive from negative patients and maintained the regular hospital clean of COVID-19 allowing treatment continuation of regular non-COVID-19 patients.

Major Impacts of Widespread Structural Variation on Gene Expression and Crop Improvement in Tomato.

Structural variants (SVs) underlie important crop improvement and domestication traits. However, resolving the extent, diversity, and quantitative impact of SVs has been challenging. We used long-read nanopore sequencing to capture 238,490 SVs in 100 diverse tomato lines. This panSV genome, along with 14 new reference assemblies, revealed large-scale intermixing of diverse genotypes, as well as thousands of SVs intersecting genes and cis-regulatory regions. Hundreds of SV-gene pairs exhibit subtle and significant expression changes, which could broadly influence quantitative trait variation. By combining quantitative genetics with genome editing, we show how multiple SVs that changed gene dosage and expression levels modified fruit flavor, size, and production. In the last example, higher order epistasis among four SVs affecting three related transcription factors allowed introduction of an important harvesting trait in modern tomato. Our findings highlight the underexplored role of SVs in genotype-to-phenotype relationships and their widespread importance and utility in crop improvement.

Teaching physicians the GPGP method promotes deprescribing in both inpatient and outpatient settings.

BACKGROUND: In complex older patients, inappropriate medication use and polypharmacy (IMUP) are commonplace and increasing exponentially. Reducing IMUP is a challenge in multiple clinical contexts, including acute admission and family practice, due to several key barriers. In the global effort against this epidemic, educational programs geared toward changing physicians' prescribing patterns represent an important means of promoting deprescribing. METHODS: This is a nonrandomized, controlled interventional study investigating polypharmacy outcomes and prescribing patterns in patients whose physicians were trained in the Good Palliative-Geriatric Practice (GPGP) method, an algorithm for the reduction of polypharmacy, with patients whose physicians were not. Training involved a one-time, full-day workshop led by a senior geriatrician. Two separate settings were examined. In the inpatient setting, one internal medicine ward was trained and compared with another ward which was not trained. In the family practice setting, 28 physicians were trained and compared with practices of 15 physicians not trained. Patients were above the age of 70, representative of the general geriatric population, and not terminally ill. RESULTS: In the inpatient arm, the intervention group (n = 100) experienced a decrease in medications prescribed from admission to discharge of 18.5%, compared with a decrease of 1.9% in the control group (n = 100, difference between groups p < 0.0001). In the outpatient arm, the intervention group (n = 100) experienced a decrease in medication number of 6.1% compared with 0.07% in the control group (n = 100, difference between groups p = 0.001) over a 6-month period. Preferential decreases in specific drug classes were observed in both groups, including benzodiazepines, psychotropics, and antihypertensives. CONCLUSIONS: A one-time educational intervention based on GPGP can change prescribing patterns in both outpatient and inpatient settings leading to a moderate reduction in polypharmacy. Future work should focus on longitudinal interventions, and longer-term clinical outcomes such as morbidity, mortality, and quality of life.

Aviator's Fluid Balance During Military Flight.

INTRODUCTION: A loss of 1% or more of bodyweight due to dehydration has a negative effect on cognitive performance, which could critically affect flight safety. There is no mention in the literature concerning the amounts of military pilots' fluid loss during flight. The aim of this study was to quantify fluid loss of pilots during military flight. METHODS: There were 48 aviators (mean age 23.9) from the Israeli Air Force who participated in the study, which included 104 training flights in various flight platforms. Bodyweight, urine specific gravity, and environmental heat strain were measured before and after each flight. Fluid loss was calculated as the weight differences before and after the flight. We used a univariate and one-way ANOVA to analyze the effect of different variables on the fluid loss. RESULTS: The mean fluid loss rate was 462 ml · h-1. The results varied among different aircraft platforms and depended on flight duration. Blackhawk pilots lost the highest amount of fluids per flight, albeit had longer flights (mean 108 min compared to 35.5 in fighter jets). Jet fighter pilots had the highest rate of fluid loss per hour of flight (up to 692 ml, extrapolated). CONCLUSION: Overall, at 11 flights (11%) aircrew completed their flight with a meaningful fluid loss. We conclude that military flights may be associated with significant amount of fluid loss among aircrew.Levkovsky A, Abot-Barkan S, Chapnik L, Doron O, Levy Y, Heled Y, Gordon B. Aviator's fluid balance during military flight. Aerosp Med Hum Perform. 2018; 89(2):9498.

Vision improvement in pilots with presbyopia following perceptual learning.

Israeli Air Force (IAF) pilots continue flying combat missions after the symptoms of natural near-vision deterioration, termed presbyopia, begin to be noticeable. Because modern pilots rely on the displays of the aircraft control and performance instruments, near visual acuity (VA) is essential in the cockpit. We aimed to apply a method previously shown to improve visual performance of presbyopes, and test whether presbyopic IAF pilots can overcome the limitation imposed by presbyopia. Participants were selected by the IAF aeromedical unit as having at least initial presbyopia and trained using a structured personalized perceptual learning method (GlassesOff application), based on detecting briefly presented low-contrast Gabor stimuli, under the conditions of spatial and temporal constraints, from a distance of 40 cm. Our results show that despite their initial visual advantage over age-matched peers, training resulted in robust improvements in various basic visual functions, including static and temporal VA, stereoacuity, spatial crowding, contrast sensitivity and contrast discrimination. Moreover, improvements generalized to higher-level tasks, such as sentence reading and aerial photography interpretation (specifically designed to reflect IAF pilots' expertise in analyzing noisy low-contrast input). In concert with earlier suggestions, gains in visual processing speed are plausible to account, at least partially, for the observed training-induced improvements.

Hearing Loss in Israeli Air Force Aviators: Natural History and Risk Factors.

OBJECTIVE: To investigate the natural history of hearing loss (HL) in Israeli military aviators and its risk factors. METHODS: Audiometric results of aviators with available audiometry at ages 30 and 40 years, and up to their last available audiometry were retrieved. HL DEFINITION: pure-tone threshold (PTT) of 30 dB or higher in at least one frequency in at least one ear, moderate-to-severe (M-S) HL as PTT of 45 dB or higher, and suspected noise-induced HL (NIHL) as HL at 3 to 6 kHz. Potential risk factors for HL were assessed by the χ(2) test and logistic regression models. RESULTS: 298 aviators were included. Rates of HL increased with age, up to 57.5% at age 50. All M-S HL at age 50 years had clues on previous examinations, but new HL was observed in all ages. Age was found as a statistically significant risk factor, but aircraft type was not. Total flying hours were found to be an independent risk factor for suspected NIHL only. Self-reported earplug use was not found to protect from HL, with methodological limitations. CONCLUSIONS: HL is prevalent in aviators. Age and total flying hours are risk factors, the latter probably only for NIHL, whereas aircraft type is not.

The Ecology of Medical Care Among Israeli Military Aviators.

BACKGROUND: The ecology of medical care model has been used in various populations with varying results. We aimed to apply this model in the population of Israeli Air Force (IAF) aviators. METHODS: An anonymous questionnaire was presented to all Israeli Air Force aviators during their mandatory yearly check-up over 1 yr starting on November 26th, 2012. The questionnaire contained items on demographic, personal, and military details, as well as items on the presence of clinical symptoms, and various health care contacts in the previous month. We assessed the differences between career and reserve personnel using a X2 test. RESULTS: There were 325 aviators who completed the questionnaire (2 women, 132 reserves). Clinical symptoms were reported by 62.5% of the responders. Over half (52.6%) had any health care encounter: 23.7% with a dentist, 17.9% with non-MD therapists, 12.6% with a specialist, and 11.7% with a primary physician. A significant difference between reserve and career personnel was found only in primary care visits. Out of the aviators who reported having clinical symptoms, 70.9% did not visit a physician. Of those who did not seek medical care, 42.4% reported that the symptoms were viewed as unimportant, 41% thought they would disappear by themselves, 40.3% could not find time for treatment. CONCLUSIONS: Aviators in the IAF have similar rate of clinical symptoms as in other unselected populations. Those who report symptoms usually do not visit a physician for treatment. When they do seek advice it is mostly from non-MD practitioners.Gordon B, Levy Y, Yemini T, Carmon E, Erlich Y, Hermoni D. The ecology of medical care among Israeli military aviators. Aerosp Med Hum Perform. 2016; 87(12):1036-1040.

Back symptoms in aviators flying different aircraft.

INTRODUCTION: Back pain is a common complaint among military aviators of various aircraft. We attempted to define the epidemiologic characteristics of this complaint in military aviators of the Israeli Air Force. METHODS: Aviators of various aircraft (fighter, attack helicopter, utility helicopter, and transport and cargo) completed 566 questionnaires. The questionnaires included various demographic variables as well as questions specifically addressing type of aircraft, location, and severity of pain. Questionnaires were analyzed according to aircraft type, weekly and total number of flight hours. RESULTS: Back pain was significantly more common among utility and attack helicopter pilots. Compared with only 64.02% of fighter pilots, 89.38% of utility and 74.55% of attack helicopter pilots reported some degree of back pain. Cervical region pain was more common among fighter pilots (47.2%) and utility helicopter pilots (47.3%) compared with attack helicopter (36.4%) and transport (22.3%) pilots. Cervical region pain of moderate-severe degree was more common among utility helicopter pilots (7.1%). Mid and low back pain at all degrees of severity were more common among helicopter pilots. A significant proportion of subjects suffered from pain in multiple regions, particularly among utility helicopter pilots (32.74%). Severity of pain was graded higher in all three regions (cervical, mid, and lower back) in utility helicopter pilots. CONCLUSIONS: Utility helicopter pilots have more prevalent and more severe back pain than pilots of other platforms. Yet, it is difficult to make a clear association between type of aircraft and the region of back pain.

Correlation between eosinophil count and methacholine challenge test in asymptomatic subjects.

BACKGROUND: Methacholine challenge test is used to identify airway hyperresponsiveness (AHR). Total eosinophil counts in peripheral blood reflect asthmatic activity and are useful for early detection of exacerbations. Correlation between the two is poorly defined, particularly in asymptomatic subjects. OBJECTIVE: The aim is to define correlation between methacholine challenge test and peripheral blood eosinophilia. METHODS: All flight academy candidates evaluated in the Israeli Air Force Aero Medical Center between the years 2010 and 2011 were included. Candidates were referred to methacholine challenge test based on a personal history of asthma or wheezing in childhood, a first-degree relative with the diagnosis of asthma, or an abnormal spirometry. All methacholine tests were analyzed retrospectively. RESULTS: Asymptomatic subjects with a positive methacholine challenge test demonstrated significantly (p < .002) higher levels of absolute eosinophil count compared with the group with a negative methacholine test (0.46 ± 0.21 vs. 0.21 ± 0.01 K/µL). Total white blood cell and neutrophil counts were higher in the group with a positive methacholine test compared with the group with a negative methacholine test, but to a lesser extent (7.1 ± 0.25 vs. 6.6 ± 0.09 K/µL, p = .04 and 3.9 ± 0.24 vs. 3.5 ± 0.07 K/µL, p = .04, respectively). No association was demonstrated between eosinophil count and severity of AHR expressed by the methacholine concentration evoking a response. CONCLUSION: There is a strong association between eosinophil count and AHR in asymptomatic subjects.

Screening criteria for diagnosis of infantile feeding disorders as a cause of poor feeding or food refusal.

OBJECTIVES: Infantile feeding disorders (IFDs) are a common cause of food refusal, failure to thrive, and vomiting, but they may be difficult to diagnose. We have previously identified certain patterns of pathological feeding and behaviors as high-risk characteristics for IFDs and subsequently developed the diagnostic Wolfson criteria. Here, we evaluate these high-risk behaviors and prospectively compare the Wolfson criteria with 2 existing classifications of IFD, the Chatoor and that in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). PATIENTS AND METHODS: Infants and young children referred for food refusal were invited to participate by completing a feeding pattern questionnaire. Following physicians' interview and examination, patients were scored by all 3 criteria and enrolled in a structured treatment program for IFD. Infants whose food refusal was associated with an organic cause served as a comparison group. The ability of the criteria to detect IFD and to predict response to therapy was compared with an intention-to-treat analysis. RESULTS: Eighty-five infants with new-onset IFD and 55 controls were included. The Wolfson criteria, Chatoor, and DSM-IV accurately diagnosed 100%, 77%, and 56% of the patients with IFD, respectively. Anticipatory gagging occurred in 47% of the children with IFD compared to 2% controls (P < 0.001). The response to therapy was similar among the 3 criteria (73-76%), suggesting that the Wolfson criteria did not incorrectly diagnose organic disease as IFD. The 20 infants who were diagnosed as having IFD by Wolfson but not by Chatoor responded equally well (80%) to an IFD treatment program. CONCLUSIONS: Diagnostic criteria of IFD that are based on food refusal, pathological feeding, and anticipatory gagging have a higher detection rate than the present criteria and are simpler to implement.

Diagnostic clues for identification of nonorganic vs organic causes of food refusal and poor feeding.

OBJECTIVES: Food refusal, poor feeding, and somatic symptoms such as vomiting, gagging, irritability and failure to thrive (FTT) are commonly found in both infantile feeding disorders (IFD) and common treatable medical conditions. Present diagnostic classifications for diagnosing IFD are complex and difficult to apply in daily practice, leading to underdiagnosis and delay in diagnosis of IFD. We attempted to identify parental and infantile behaviour patterns or symptoms that could help distinguish between organic or behavioural causes for these symptoms. METHODS: We screened 226 children with poor feeding. After exclusion criteria, we divided the remaining 151 into 2 groups. The nonorganic group (n=83) included patients with onset of symptoms before age 2, persistent food aversion longer than 1 month, and a response to behavioural intervention. The second group consisted of children (n=68) presenting with similar characteristics, who responded to medical or nutritional therapy in which a final diagnosis of gastro-esophageal reflux disease, milk allergy, or idiopathic or nutritional FTT was made. RESULTS: Poor intake, poor weight gain, or vomiting did not discriminate between organic and nonorganic causes. Factors indicating the presence of a behavioural cause included food refusal, food fixation, abnormal parental feeding practices, onset after a specific trigger, and presence of anticipatory gagging (P<0.0001 for all). CONCLUSIONS: Integration of a few structured questions regarding infant behaviour, parental feeding practices, infant symptoms, and triggers for the onset of symptoms may help clinicians distinguish between organic and nonorganic causes for food refusal or low intake FTT.

Influenza outbreak control in confined settings.

Influenza may rapidly disseminate within populations living in confined settings, causing considerable morbidity and disrupting daily activities. We describe an influenza A outbreak on a military base where 3,000 young adults, most of whom were unvaccinated, lived in close daily contact. Visits to the base clinic by 48 persons with acute respiratory illness within 2 days allowed early identification of this outbreak and prompted immediate epidemiologic investigation. Overall, 85 personnel (2.83% of base population) met the case definition for influenzalike illness. On-site laboratory confirmation with field detection kits, rapid implementation of respiratory illness control protocols, and a mass vaccination campaign were applied to limit disease dissemination. The outbreak was halted 14 days after the mass vaccination campaign was completed. We review the control measures available for controlling influenza outbreaks in confined settings and discuss the role of rapid mass vaccination within this context.