Comparison of Influenza and Coronavirus Disease 2019-Associated Hospitalizations Among Children Younger Than 18 Years Old in the United States: FluSurv-NET (October-April 2017-2021) and COVID-NET (October 2020-September 2021).

BACKGROUND: Influenza virus and SARS-CoV-2 are significant causes of respiratory illness in children. METHODS: Influenza- and COVID-19-associated hospitalizations among children <18 years old were analyzed from FluSurv-NET and COVID-NET, 2 population-based surveillance systems with similar catchment areas and methodology. The annual COVID-19-associated hospitalization rate per 100 000 during the ongoing COVID-19 pandemic (1 October 2020-30 September 2021) was compared with influenza-associated hospitalization rates during the 2017-2018 through 2019-2020 influenza seasons. In-hospital outcomes, including intensive care unit (ICU) admission and death, were compared. RESULTS: Among children <18 years, the COVID-19-associated hospitalization rate (48.2) was higher than influenza-associated hospitalization rates: 2017-2018 (33.5), 2018-2019 (33.8), and 2019-2020 (41.7). The COVID-19-associated hospitalization rate was higher among adolescents 12-17 years old (COVID-19: 59.9; influenza range: 12.2-14.1), but similar or lower among children 5-11 (COVID-19: 25.0; influenza range: 24.3-31.7) and 0-4 (COVID-19: 66.8; influenza range: 70.9-91.5) years old. Among children <18 years, a higher proportion with COVID-19 required ICU admission compared with influenza (26.4% vs 21.6%; P < .01). Pediatric deaths were uncommon during both COVID-19- and influenza-associated hospitalizations (0.7% vs 0.5%; P = .28). CONCLUSIONS: In the setting of extensive mitigation measures during the COVID-19 pandemic, the annual COVID-19-associated hospitalization rate during 2020-2021 was higher among adolescents and similar or lower among children <12 years compared with influenza during the 3 seasons before the COVID-19 pandemic. COVID-19 adds substantially to the existing burden of pediatric hospitalizations and severe outcomes caused by influenza and other respiratory viruses.

Vital Signs: Influenza Hospitalizations and Vaccination Coverage by Race and Ethnicity-United States, 2009-10 Through 2021-22 Influenza Seasons.

Introduction: CDC estimates that influenza resulted in 9-41 million illnesses, 140,000-710,000 hospitalizations, and 12,000-52,000 deaths annually during 2010-2020. Persons from some racial and ethnic minority groups have historically experienced higher rates of severe influenza and had lower influenza vaccination coverage compared with non-Hispanic White (White) persons. This report examines influenza hospitalization and vaccination rates by race and ethnicity during a 12-13-year period (through the 2021-22 influenza season). Methods: Data from population-based surveillance for laboratory-confirmed influenza-associated hospitalizations in selected states participating in the Influenza-Associated Hospitalization Surveillance Network (FluSurv-NET) from the 2009-10 through 2021-22 influenza seasons (excluding 2020-21) and influenza vaccination coverage data from the Behavioral Risk Factor Surveillance System (BRFSS) from the 2010-11 through 2021-22 influenza seasons were analyzed by race and ethnicity. Results: From 2009-10 through 2021-22, age-adjusted influenza hospitalization rates (hospitalizations per 100,000 population) were higher among non-Hispanic Black (Black) (rate ratio [RR] = 1.8), American Indian or Alaska Native (AI/AN; RR = 1.3), and Hispanic (RR = 1.2) adults, compared with the rate among White adults. During the 2021-22 season, influenza vaccination coverage was lower among Hispanic (37.9%), AI/AN (40.9%), Black (42.0%), and other/multiple race (42.6%) adults compared with that among White (53.9%) and non-Hispanic Asian (Asian) (54.2%) adults; coverage has been consistently higher among White and Asian adults compared with that among Black and Hispanic adults since the 2010-11 season. The disparity in vaccination coverage by race and ethnicity was present among those who reported having medical insurance, a personal health care provider, and a routine medical checkup in the past year. Conclusions and Implications for Public Health Practice: Racial and ethnic disparities in influenza disease severity and influenza vaccination coverage persist. Health care providers should assess patient vaccination status at all medical visits and offer (or provide a referral for) all recommended vaccines. Tailored programmatic efforts to provide influenza vaccination through nontraditional settings, along with national and community-level efforts to improve awareness of the importance of influenza vaccination in preventing illness, hospitalization, and death among racial and ethnic minority communities might help address health care access barriers and improve vaccine confidence, leading to decreases in disparities in influenza vaccination coverage and disease severity.

Interim Estimates of 2021-22 Seasonal Influenza Vaccine Effectiveness - United States, February 2022.

In the United States, annual vaccination against seasonal influenza is recommended for all persons aged ≥6 months except when contraindicated (1). Currently available influenza vaccines are designed to protect against four influenza viruses: A(H1N1)pdm09 (the 2009 pandemic virus), A(H3N2), B/Victoria lineage, and B/Yamagata lineage. Most influenza viruses detected this season have been A(H3N2) (2). With the exception of the 2020-21 season, when data were insufficient to generate an estimate, CDC has estimated the effectiveness of seasonal influenza vaccine at preventing laboratory-confirmed, mild/moderate (outpatient) medically attended acute respiratory infection (ARI) each season since 2004-05. This interim report uses data from 3,636 children and adults with ARI enrolled in the U.S. Influenza Vaccine Effectiveness Network during October 4, 2021-February 12, 2022. Overall, vaccine effectiveness (VE) against medically attended outpatient ARI associated with influenza A(H3N2) virus was 16% (95% CI = -16% to 39%), which is considered not statistically significant. This analysis indicates that influenza vaccination did not reduce the risk for outpatient medically attended illness with influenza A(H3N2) viruses that predominated so far this season. Enrollment was insufficient to generate reliable VE estimates by age group or by type of influenza vaccine product (1). CDC recommends influenza antiviral medications as an adjunct to vaccination; the potential public health benefit of antiviral medications is magnified in the context of reduced influenza VE. CDC routinely recommends that health care providers continue to administer influenza vaccine to persons aged ≥6 months as long as influenza viruses are circulating, even when VE against one virus is reduced, because vaccine can prevent serious outcomes (e.g., hospitalization, intensive care unit (ICU) admission, or death) that are associated with influenza A(H3N2) virus infection and might protect against other influenza viruses that could circulate later in the season.

Changes in Influenza and Other Respiratory Virus Activity During the COVID-19 Pandemic - United States, 2020-2021.

The COVID-19 pandemic and subsequent implementation of nonpharmaceutical interventions (e.g., cessation of global travel, mask use, physical distancing, and staying home) reduced transmission of some viral respiratory pathogens (1). In the United States, influenza activity decreased in March 2020, was historically low through the summer of 2020 (2), and remained low during October 2020-May 2021 (<0.4% of respiratory specimens with positive test results for each week of the season). Circulation of other respiratory pathogens, including respiratory syncytial virus (RSV), common human coronaviruses (HCoVs) types OC43, NL63, 229E, and HKU1, and parainfluenza viruses (PIVs) types 1-4 also decreased in early 2020 and did not increase until spring 2021. Human metapneumovirus (HMPV) circulation decreased in March 2020 and remained low through May 2021. Respiratory adenovirus (RAdV) circulated at lower levels throughout 2020 and as of early May 2021. Rhinovirus and enterovirus (RV/EV) circulation decreased in March 2020, remained low until May 2020, and then increased to near prepandemic seasonal levels. Circulation of respiratory viruses could resume at prepandemic levels after COVID-19 mitigation practices become less stringent. Clinicians should be aware of increases in some respiratory virus activity and remain vigilant for off-season increases. In addition to the use of everyday preventive actions, fall influenza vaccination campaigns are an important component of prevention as COVID-19 mitigation measures are relaxed and schools and workplaces resume in-person activities.

Hospitalizations Associated with COVID-19 Among Children and Adolescents - COVID-NET, 14 States, March 1, 2020-August 14, 2021.

Although COVID-19-associated hospitalizations and deaths have occurred more frequently in adults,† COVID-19 can also lead to severe outcomes in children and adolescents (1,2). Schools are opening for in-person learning, and many prekindergarten children are returning to early care and education programs during a time when the number of COVID-19 cases caused by the highly transmissible B.1.617.2 (Delta) variant of SARS-CoV-2, the virus that causes COVID-19, is increasing.§ Therefore, it is important to monitor indicators of severe COVID-19 among children and adolescents. This analysis uses Coronavirus Disease 2019-Associated Hospitalization Surveillance Network (COVID-NET)¶ data to describe COVID-19-associated hospitalizations among U.S. children and adolescents aged 0-17 years. During March 1, 2020-August 14, 2021, the cumulative incidence of COVID-19-associated hospitalizations was 49.7 per 100,000 children and adolescents. The weekly COVID-19-associated hospitalization rate per 100,000 children and adolescents during the week ending August 14, 2021 (1.4) was nearly five times the rate during the week ending June 26, 2021 (0.3); among children aged 0-4 years, the weekly hospitalization rate during the week ending August 14, 2021, was nearly 10 times that during the week ending June 26, 2021.** During June 20-July 31, 2021, the hospitalization rate among unvaccinated adolescents (aged 12-17 years) was 10.1 times higher than that among fully vaccinated adolescents. Among all hospitalized children and adolescents with COVID-19, the proportions with indicators of severe disease (such as intensive care unit [ICU] admission) after the Delta variant became predominant (June 20-July 31, 2021) were similar to those earlier in the pandemic (March 1, 2020-June 19, 2021). Implementation of preventive measures to reduce transmission and severe outcomes in children is critical, including vaccination of eligible persons, universal mask wearing in schools, recommended mask wearing by persons aged ≥2 years in other indoor public spaces and child care centers,†† and quarantining as recommended after exposure to persons with COVID-19.§§.

Pediatric trauma venous thromboembolism prediction algorithm outperforms current anticoagulation prophylaxis guidelines: a pilot study.

PURPOSE: Venous thromboembolism (VTE) in injured children is rare, but sequelae can be morbid and life-threatening. Recent trauma society guidelines suggesting that all children over 15 years old should receive thromboprophylaxis may result in overtreatment. We sought to evaluate the efficacy of a previously published VTE prediction algorithm and compare it to current recommendations. METHODS: Two institutional trauma registries were queried for all pediatric (age < 18 years) patients admitted from 2007 to 2018. Clinical data were applied to the algorithm and the area under the receiver operating characteristic (AUROC) curve was calculated to test algorithm efficacy. RESULTS: A retrospective review identified 8271 patients with 30 episodes of VTE (0.36%). The VTE prediction algorithm classified 51 (0.6%) as high risk (> 5% risk), 322 (3.9%) as moderate risk (1-5% risk) and 7898 (95.5%) as low risk (< 1% risk). AUROC was 0.93 (95% CI 0.89-0.97). In our population, prophylaxis of the 'moderate-' and 'high-risk' cohorts would outperform the sensitivity (60% vs. 53%) and specificity (96% vs. 77%) of current guidelines while anticoagulating substantially fewer patients (373 vs. 1935, p < 0.001). CONCLUSION: A VTE prediction algorithm using clinical variables can identify injured children at risk for venous thromboembolic disease with more discrimination than current guidelines. Prospective studies are needed to investigate the validity of this model. LEVEL OF EVIDENCE: III-Clinical decision rule evaluated in a single population.

Ultraviolet radiation, both UVA and UVB, influences the composition of the skin microbiome.

BACKGROUND: Studies have begun to investigate the complex relationship between host and microorganisms in non-infectious pathologies such as acne, atopic dermatitis and psoriasis. Though the skin is exposed to environmental stressors such as ultraviolet radiation (UVR), no studies exist examining the effects of both UVA and UVB on the skin microbiome. OBJECTIVE: To test the effect of UVA and UVB on human skin microbiome. METHODS: To test whether UV will alter the cutaneous microbiome, participants were exposed to doses of UVA (22-47 J/cm2 ) or UVB (100-350 mJ/cm2 ) and samples were collected. DNA was isolated and sequenced to identify the microbial composition of each sample. RESULTS: There was vast intra- and inter-subject variation at all time points, and phylum and species-level differences were identified. These included an increase in the phylum Cyanobacteria and a decrease in the family Lactobacillaceae and Pseudomonadaceae. The sensitivity of microbes to UVR and their re-colonization potential following exposure differed in UVA vs UVB samples. LIMITATIONS: The sample size was small, and the study was limited to males. CONCLUSION: The results demonstrate that UVR has profound qualitative and quantitative influences on the composition of the skin microbiome, possibly effecting skin pathology in which UVR is a factor.

Update: Influenza Activity - United States and Worldwide, May 19-September 28, 2019, and Composition of the 2020 Southern Hemisphere Influenza Vaccine.

During May 19-September 28, 2019,* low levels of influenza activity were reported in the United States, with cocirculation of influenza A and influenza B viruses. In the Southern Hemisphere seasonal influenza viruses circulated widely, with influenza A(H3) predominating in many regions; however, influenza A(H1N1)pdm09 and influenza B viruses were predominant in some countries. In late September, the World Health Organization (WHO) recommended components for the 2020 Southern Hemisphere influenza vaccine and included an update to the A(H3N2) and B/Victoria-lineage components. Annual influenza vaccination is the best means for preventing influenza illness and its complications, and vaccination before influenza activity increases is optimal. Health care providers should recommend vaccination for all persons aged ≥6 months who do not have contraindications to vaccination (1).

Update: Influenza Activity - United States, September 30, 2018-February 2, 2019.

CDC collects, compiles, and analyzes data on influenza activity and viruses in the United States. During September 30, 2018-February 2, 2019,* influenza activity† in the United States was low during October and November, increased in late December, and remained elevated through early February. As of February 2, 2019, this has been a low-severity influenza season (1), with a lower percentage of outpatient visits for influenza-like illness (ILI), lower rates of hospitalization, and fewer deaths attributed to pneumonia and influenza, compared with recent seasons. Influenza-associated hospitalization rates among children are similar to those observed in influenza A(H1N1)pdm09 predominant seasons; 28 influenza-associated pediatric deaths occurring during the 2018-19 season have been reported to CDC. Whereas influenza A(H1N1)pdm09 viruses predominated in most areas of the country, influenza A(H3N2) viruses have predominated in the southeastern United States, and in recent weeks accounted for a growing proportion of influenza viruses detected in several other regions. Small numbers of influenza B viruses (<3% of all influenza-positive tests performed by public health laboratories) also were reported. The majority of the influenza viruses characterized antigenically are similar to the cell culture-propagated reference viruses representing the 2018-19 Northern Hemisphere influenza vaccine viruses. Health care providers should continue to offer and encourage vaccination to all unvaccinated persons aged ≥6 months as long as influenza viruses are circulating. Finally, regardless of vaccination status, it is important that persons with confirmed or suspected influenza who have severe, complicated, or progressive illness; who require hospitalization; or who are at high risk for influenza complications be treated with antiviral medications.

Update: Influenza Activity in the United States During the 2018-19 Season and Composition of the 2019-20 Influenza Vaccine.

Influenza activity* in the United States during the 2018-19 season (September 30, 2018-May 18, 2019) was of moderate severity (1). Nationally, influenza-like illness (ILI)† activity began increasing in November, peaked during mid-February, and returned to below baseline in mid-April; the season lasted 21 weeks,§ making it the longest season in 10 years. Illness attributed to influenza A viruses predominated, with very little influenza B activity. Two waves of influenza A were notable during this extended season: influenza A(H1N1)pdm09 viruses from October 2018 to mid-February 2019 and influenza A(H3N2) viruses from February through May 2019. Compared with the 2017-18 influenza season, rates of hospitalization this season were lower for adults, but were similar for children. Although influenza activity is currently below surveillance baselines, testing for seasonal influenza viruses and monitoring for novel influenza A virus infections should continue year-round. Receiving a seasonal influenza vaccine each year remains the best way to protect against seasonal influenza and its potentially severe consequences.

Pediatric Minor Traumatic Brain Injury With Intracranial Hemorrhage: Identifying Low-Risk Patients Who May Not Benefit From ICU Admission.

BACKGROUND: Pediatric patients with any severity of traumatic intracranial hemorrhage (tICH) are often admitted to intensive care units (ICUs) for early detection of secondary injury. We hypothesize that there is a subset of these patients with mild injury and tICH for whom ICU care is unnecessary. OBJECTIVES: To quantify tICH frequency and describe disposition and to identify patients at low risk of inpatient critical care intervention (CCI). METHODS: We retrospectively reviewed patients aged 0 to 17 years with tICH at a single level I trauma center from 2008 to 2013. The CCI included mechanical ventilation, invasive monitoring, blood product transfusion, hyperosmolar therapy, and neurosurgery. Binary recursive partitioning analysis led to a clinical decision instrument classifying patients as low risk for CCI. RESULTS: Of 296 tICH admissions without prior CCI in the field or emergency department, 29 had an inpatient CCI. The decision instrument classified patients as low risk for CCI when patients had absence of the following: midline shift, depressed skull fracture, unwitnessed/unknown mechanism, and other nonextremity injuries. This clinical decision instrument produced a high likelihood of excluding patients with CCI (sensitivity, 96.6%; 95% confidence interval, 82.2%-99.9%) from the low-risk group, with a negative likelihood ratio of 0.056 (95% confidence interval, -0.053-0.166). The decision instrument misclassified 1 patient with CCI into the low-risk group, but would have impacted disposition of 164 pediatric ICU admissions through 5 years (55% of the sample). CONCLUSIONS: A subset of low-risk patients may not require ICU admission. The proposed decision rule identified low-risk children with tICH who may be observable outside an ICU, although this rule requires external validation before implementation.

Systematic Assessment of Multiple Routine and Near Real-Time Indicators to Classify the Severity of Influenza Seasons and Pandemics in the United States, 2003-2004 Through 2015-2016.

Assessments of influenza season severity can guide public health action. We used the moving epidemic method to develop intensity thresholds (ITs) for 3 US surveillance indicators from the 2003-2004 through 2014-2015 influenza seasons (excluding the 2009 pandemic). The indicators were: 1) outpatient visits for influenza-like illness; 2) influenza-related hospitalizations; and 3) influenza- and pneumonia-related deaths. ITs were developed for the population overall and separately for children, adults, and older adults, and they were set at the upper limit of the 50% (IT50), 90% (IT90), and 98% (IT98) 1-sided confidence intervals of the geometric mean of each season's 3 highest values. Severity was classified as low if ≥2 systems peaked below IT50, moderate if ≥2 peaked between IT50 and IT90, high if ≥2 peaked between IT90 and IT98, and very high if ≥2 peaked above IT98. We pilot-tested this method with the 2015-2016 season and the 2009 pandemic. Overall, 4 seasons were classified as low severity, 7 as moderate, 2 as high, and none as very high. Among the age groups, older adults had the most seasons (n = 3) classified as high, and children were the only group to have seasons (n = 2) classified as very high. We will apply this method to classify the severity of future seasons and inform pandemic response.

Identification of genetic modifiers of age-at-onset for familial Parkinson's disease.

Parkinson's disease (PD) is the most common cause of neurodegenerative movement disorder and the second most common cause of dementia. Genes are thought to have a stronger effect on age-at-onset of PD than on risk, yet there has been a phenomenal success in identifying risk loci but not age-at-onset modifiers. We conducted a genome-wide study for age-at-onset. We analysed familial and non-familial PD separately, per prior evidence for strong genetic effect on age-at-onset in familial PD. GWAS was conducted in 431 unrelated PD individuals with at least one affected relative (familial PD) and 1544 non-familial PD from the NeuroGenetics Research Consortium (NGRC); an additional 737 familial PD and 2363 non-familial PD were used for replication. In familial PD, two signals were detected and replicated robustly: one mapped to LHFPL2 on 5q14.1 (PNGRC = 3E-8, PReplication = 2E-5, PNGRC + Replication = 1E-11), the second mapped to TPM1 on 15q22.2 (PNGRC = 8E-9, PReplication = 2E-4, PNGRC + Replication = 9E-11). The variants that were associated with accelerated onset had low frequencies (<0.02). The LHFPL2 variant was associated with earlier onset by 12.33 [95% CI: 6.2; 18.45] years in NGRC, 8.03 [2.95; 13.11] years in replication, and 9.79 [5.88; 13.70] years in the combined data. The TPM1 variant was associated with earlier onset by 15.30 [8.10; 22.49] years in NGRC, 9.29 [1.79; 16.79] years in replication, and 12.42 [7.23; 17.61] years in the combined data. Neither LHFPL2 nor TPM1 was associated with age-at-onset in non-familial PD. LHFPL2 (function unknown) is overexpressed in brain tumours. TPM1 encodes a highly conserved protein that regulates muscle contraction, and is a tumour-suppressor gene.

Stool Immune Profiles Evince Gastrointestinal Inflammation in Parkinson's Disease.

BACKGROUND: Gastrointestinal symptoms are common in Parkinson's disease and frequently precede the development of motor impairments. Intestinal inflammation has been proposed as a driver of disease pathology, and evaluation of inflammatory mediators in stool could possibly identify valuable early-stage biomarkers. We measured immune- and angiogenesis-related proteins in human stool to examine inflammatory profiles associated with Parkinson's disease. METHODS: Stool samples and subjects' self-reported metadata were obtained from 156 individuals with Parkinson's disease and 110 without, including spouse and nonhousehold controls. Metadata were probed for disease-associated differences, and levels of 37 immune and angiogenesis factors in stool homogenates were measured by multiplexed immunoassay and compared across experimental groups. RESULTS: Parkinson's disease patients reported greater incidence of intestinal disease and digestive problems than controls. Direct comparison of levels of stool analytes in patients and controls revealed elevated vascular endothelial growth factor receptor 1, interleukin-1α, and CXCL8 in patients' stool. Paired comparison of patients and spouses suggested higher levels of multiple factors in patients, but this was complicated by sex differences. Sex, body mass index, a history of smoking, and use of probiotics were found to strongly influence levels of stool analytes. Multivariate analysis accounting for these and other potential confounders confirmed elevated levels of interleukin-1α and CXCL8 and also revealed increased interleukin-1ß and C-reactive protein in stool in Parkinson's disease. These differences were not dependent on subject age or disease duration. CONCLUSIONS: Levels of stool immune factors indicate that intestinal inflammation is present in patients with Parkinson's disease. © 2018 International Parkinson and Movement Disorder Society.

Influenza Activity - United States, September 30-December 1, 2018.

Influenza activity in the United States was low during October 2018, and, although it increased slowly during November, activity remains low across most of the country.* During the week ending December 1, 2018, the percentage of outpatient visits for influenza-like illness† (ILI) was equal to the national baseline§ (Figure) and was at or slightly above the region-specific baseline in four of the 10 U.S. Department of Health and Human Services regions¶ (Regions 4 and 7-9). The majority of jurisdictions experienced minimal or low ILI activity since September 30; however, two experienced moderate ILI activity, and two experienced high ILI activity** during the week ending December 1. The percentage of deaths attributed to pneumonia and influenza remains below the epidemic threshold,†† and the rate of influenza-associated hospitalizations remains low. Five laboratory-confirmed, influenza-associated pediatric deaths occurring since September 30 have been reported to CDC. During the week ending December 1, the majority of jurisdictions (40 states, the District of Columbia, Puerto Rico, and U.S. Virgin Islands) reported sporadic or local geographic spread of influenza activity, nine states reported regional activity, and one state reported widespread activity.§§.

Update: Influenza Activity - United States and Worldwide, May 20-October 13, 2018.

During May 20-October 13, 2018,* low levels of influenza activity were reported in the United States, with a mix of influenza A and B viruses circulating. Seasonal influenza activity in the Southern Hemisphere was low overall, with influenza A(H1N1)pdm09 predominating in many regions. Antigenic testing of available influenza A and B viruses indicated that no significant antigenic drift in circulating viruses had emerged. In late September, the components for the 2019 Southern Hemisphere influenza vaccine were selected and included an incremental update to the A(H3N2) vaccine virus used in egg-based vaccine manufacturing; no change was recommended for the A(H3N2) component of cell-manufactured or recombinant influenza vaccines. Annual influenza vaccination is the best method for preventing influenza illness and its complications, and all persons aged ≥6 months who do not have contraindications should receive influenza vaccine, preferably before the onset of influenza circulation in their community, which often begins in October and peaks during December-February. Health care providers should offer vaccination by the end of October and should continue to recommend and administer influenza vaccine to previously unvaccinated patients throughout the 2018-19 influenza season (1). In addition, during May 20-October 13, a small number of nonhuman influenza "variant" virus infections† were reported in the United States; most were associated with exposure to swine. Although limited human-to-human transmission might have occurred in one instance, no ongoing community transmission was identified. Vulnerable populations, especially young children and other persons at high risk for serious influenza complications, should avoid swine barns at agricultural fairs, or close contact with swine.§.

Update: Influenza Activity - United States, October 1, 2017-February 3, 2018.

Influenza activity in the United States began to increase in early November 2017 and rose sharply from December through February 3, 2018; elevated influenza activity is expected to continue for several more weeks. Influenza A viruses have been most commonly identified, with influenza A(H3N2) viruses predominating, but influenza A(H1N1)pdm09 and influenza B viruses were also reported. This report summarizes U.S. influenza activity* during October 1, 2017-February 3, 2018,† and updates the previous summary (1).

Update: Influenza Activity in the United States During the 2017-18 Season and Composition of the 2018-19 Influenza Vaccine.

The United States 2017-18 influenza season (October 1, 2017-May 19, 2018) was a high severity season with high levels of outpatient clinic and emergency department visits for influenza-like illness (ILI), high influenza-related hospitalization rates, and elevated and geographically widespread influenza activity across the country for an extended period. Nationally, ILI activity began increasing in November, reaching an extended period of high activity during January-February, and remaining elevated through March. Influenza A(H3N2) viruses predominated through February and were predominant overall for the season; influenza B viruses predominated from March onward. This report summarizes U.S. influenza activity* during October 1, 2017-May 19, 2018.†.

Methotrexate use in allergic contact dermatitis: a retrospective study.

BACKGROUND: Methotrexate, a folate antimetabolite, is used to treat atopic dermatitis and psoriasis. Although methotrexate's therapeutic efficacy has been noted in the literature, there are few data on the efficacy of methotrexate treatment for allergic contact dermatitis. OBJECTIVE: To evaluate the efficacy and tolerability of methotrexate in treating allergic contact dermatitis at a single institution, and also to assess methotrexate efficacy in patients with chronic, unavoidable allergen exposure. METHODS: We performed a retrospective chart review of 32 patients diagnosed with allergic contact dermatitis by positive patch test reactions, and who received treatment with methotrexate from November 2010 to November 2014. Demographic and treatment-associated data were collected from electronic medical records. Ten patients were identified as allergen non-avoiders secondary to their occupation, and were subgrouped as such. RESULTS: Seventy-eight per cent (25/32) of patients showed either a partial or a complete response. Methotrexate had a comparable efficacy rate in the allergen non-avoiders subset, at 10 of 10. Of the 32 patients, 23% (5/22) had complete clearance of their dermatitis, and 1/10 of allergen non-avoiders had complete clearance of their dermatitis. CONCLUSION: Methotrexate is a well-tolerated and effective treatment for allergic contact dermatitis, and shows comparable efficacy to immunomodulatory agents such as cyclosporine and azathioprine, with robust efficacy despite persistent allergen exposure in patients with allergic contact dermatitis.