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Background. Pneumonia was a common complication among hospitalized patients with 2009 pandemic influenza A H1N1 [pH1N1] in the United States in 2009. Methods. Through 2 national case series conducted during spring and fall of 2009, medical records were reviewed. A pneumonia case was defined as a hospitalize dp erson with laboratory-conf irmed pH1N1 virus and a chest radiographic report consistent with pneumonia based on agreement among 3 physicians. Results. Of 451 patients with chest radiographs performed, 195 (43%) had pneumonia (spring, 106 of 237 [45%]; fall, 89 of 214 [42%]). Compared with 256 patients without pneumonia, these 195 patients with pneumonia were more likely to be admitted to the intensive care unit (52% vs 16%), have acute respiratory distress syndrome (ARDS; 26% vs 2%), have sepsis (18% vs 3%), and die (17% vs 2%; P , .0001). One hundred eighteen (61%) of the patients with pneumonia had $1 underlying condition. Bacterial infections were reported in 13 patients with pneumonia and 2 patients without pneumonia. Patients with pneumonia, when compared with patients without pneumonia, were equally likely to receive influenza antiviral agents (78% vs 79%) but less likely to receive antiviral agents within #2 days of illness onset (28% vs 50%; P , .0001). Conclusions. Hospitalized patients with pH1N1 and pneumonia were at risk for severe outcomes including ARDS, sepsis, and death; antiviral treatment was often delayed. In the absence of accurate pneumonia diagnostics, patients hospitalized with suspected influenza and lung infiltrates on chest radiography should receive early and aggressive treatment with antibiotics and influenza antiviral agents.

Influenza causes substantial morbidity in children in the United States each year. The 2009 influenza A (H1N1) pandemic disproportionately affected the pediatric population and resulted in a substantially increased number of hospitalizations and deaths among children. Early influenza antiviral treatment reduces the duration of illness, frequency of complications, antibiotic use, and health care utilization costs attributable to influenza. A comprehensive strategy to reduce influenza-associated hospitalizations and deaths among children should include empiric antiviral treatment for suspected or confirmed influenza of any severity in children who are hospitalized; who have severe, complicated, or progressive illness; or who are at high risk for influenza complications. Here, we summarize data on the burden of influenza among children in the United States, the indications for influenza antiviral treatment among children, the available evidence for influenza antiviral treatment, and antiviral treatment considerations, including resistance and adverse events.

We sought to determine whether maternal vaccination during pregnancy was associated with a reduced risk of laboratory-confirmed influenza hospitalizations in infants6 months old. Active population-based, laboratory-confirmed influenza surveillance was conducted in children hospitalized with fever and/or respiratory symptoms in 3 US counties from November through April during the 2002 through 2009 influenza seasons. The exposure, influenza vaccination during pregnancy, and the outcome, positive/negative influenza testing among their hospitalized infants, were compared using logistic regression analyses. Among 1510 hospitalized infants6 months old, 151 (10%) had laboratory-confirmed influenza and 294 (19%) mothers reported receiving influenza vaccine during pregnancy. Eighteen (12%) mothers of influenza-positive infants and 276 (20%) mothers of influenza-negative infants were vaccinated (unadjusted odds ratio, 0.53; 95% confidence interval, 0.32-0.88 and adjusted odds ratio, 0.52; 95% confidence interval, 0.30-0.91). Infants of vaccinated mothers were 45-48% less likely to have influenza hospitalizations than infants of unvaccinated mothers. Our results support the current influenza vaccination recommendation for pregnant women.

Please cite this paper as: Jhung et al. (2011) Preliminary results of 2009 pandemic influenza surveillance in the United States using the Aggregate Hospitalization and Death Reporting Activity. Influenza and Other Respiratory Viruses 5(5), 321–327. Background To augment established influenza surveillance systems in the United States, the Centers for Disease Control and Prevention and the Council of State and Territorial Epidemiologists implemented the Aggregate Hospitalization and Death Reporting Activity (AHDRA) in August 2009. The AHDRA was designed to meet increased demands for timely and detailed information describing illness severity during the 2009 H1N1 influenza A (pH1N1) pandemic response. Objectives We describe the implementation of AHDRA and provide preliminary results from this new surveillance activity. Methods All 50 US states were asked to report influenza-associated hospitalizations and deaths to AHDRA each week using either a laboratory-confirmed or syndromic surveillance definition. Aggregate counts were used to calculate age-specific weekly and cumulative rates per 100 000, and laboratory-confirmed reports were used to estimate the age distribution of pH1N1 influenza-associated hospitalizations and deaths. Results From August 30, 2009, through April 6, 2010, AHDRA identified 41 689 laboratory-confirmed influenza-associated hospitalizations and 2096 laboratory-confirmed influenza-associated deaths. Aggregate Hospitalization and Death Reporting Activity rates peaked earlier than hospitalization and death rates seen in previous influenza seasons with other surveillance systems, and the age distribution of cases revealed a tendency for hospitalizations and deaths to occur in persons

During the 2009 influenza pandemic, weekly mortality data were analyzed to estimate excess mortality above a seasonally adjusted baseline modeled from prior years' data. Between the 1962-1963 and 2008-2009 seasons, among persons ≥ 25 years old, excess mortality had been substantially higher during influenza A(H3N2)-dominant years than during A(H1N1)-dominant years. Among persons ≥ 15 years of age, excess mortality was higher in the 1968-1969 influenza pandemic season than during any other season. During the 2009-2010 pandemic, among all age groups

Evaluating the impact of different social networks on the spread of respiratory diseases has been limited by a lack of detailed data on transmission outside the household setting as well as appropriate statistical methods. Here, from data collected during a H1N1 pandemic (pdm) influenza outbreak that started in an elementary school and spread in a semirural community in Pennsylvania, we quantify how transmission of influenza is affected by social networks. We set up a transmission model for which parameters are estimated from the data via Markov chain Monte Carlo sampling. Sitting next to a case or being the playmate of a case did not significantly increase the risk of infection; but the structuring of the school into classes and grades strongly affected spread. There was evidence that boys were more likely to transmit influenza to other boys than to girls (and vice versa), which mimicked the observed assortative mixing among playmates. We also investigated the presence of abnormally high transmission occurring on specific days of the outbreak. Late closure of the school (i.e., when 27% of students already had symptoms) had no significant impact on spread. School-aged individuals (6–18 y) facilitated the introduction and spread of influenza in households, but only about one in five cases aged >18 y was infected by a school-aged household member. This analysis shows the extent to which clearly defined social networks affect influenza transmission, revealing strong between-place interactions with back-and-forth waves of transmission between the school, the community, and the household.

We describe the clinical findings of HIV-infected patients hospitalized with 2009 pandemic influenza A (pH1N1). Data were derived from 3 separate case series in the United States. Among 911 adults hospitalized with pH1N1 influenza, 31 (3.4%) were HIV infected compared with an HIV prevalence of 0.45% in the general US adult population. HIV-infected influenza patients experienced similar rates of intensive care unit admission (29% vs 34%) and death (13% vs 13%) compared with non-HIV-infected patients. Among HIV-infected patients with available data, 14 (50%) of 28 patients had a CD4 cell count

Following the emergence of 2009 pandemic influenza A(H1N1) virus (pH1N1) in the United States, the incidence of pH1N1 in the community was unclear, because not all persons with influenza come to medical attention. To better estimate the incidence of pH1N1 in the community early in the pandemic, a telephone survey was conducted in 10 states. The community incidence of influenza-like illness in April 2009 was 4.7 per 100 adults (95% confidence interval: 2.8-6.6); half of adults reported seeking medical care for their illness. Such surveys may be important tools for assessing the level of illness in the general population, including those who do not seek medical care and are thus not captured using traditional surveillance methods.

Acute respiratory illness, ranging from the common cold to the influenza virus, affects people worldwide. In the U.S., roughly 3000–49,000 people die annually because of complications from influenza. Acute respiratory illness is common among international travelers. Respiratory illness is specifically problematic on cruise ships, estimated at approximately 27% of all recorded illnesses. The spread of influenza on cruise ships is a particular problem for several reasons. First, the grouping of several thousand people on board for a week or more allows considerable mixing of infected and susceptible individuals. Second, itineraries often involve travel to tropical or semitropical destinations, where influenza may circulate year round. Third, crew members can be a source of continuing infection for new passenger cohorts as infections may remain on board from one cruise to the next. The popularity of cruise ship travel has been growing over the last decade. The Cruise Lines International Association reports that the average annual passenger growth from 1990 to 2010 was 7.6%. With passengers and crew coming together from all over the world, the potential for influenza transmission, with significant morbidity, is substantial. However, little attention has been given to routine influenza surveillance on cruise ships. Influenza outbreaks on cruise ships have occurred worldwide and during all months of the year. Both passengers and crew members are affected, and many documented outbreaks occurred outside the domestic influenza season. Reported attack rates range from 3.8% to 37%. Previous outbreaks have resulted mainly from the importation of influenza from a community in which it was circulating, with subsequent prolonged person-to-person spread aboard the ship. Recommendations included the establishment of an acute respiratory infection surveillance system to allow timely interventions that are efficient and effective. Miller and colleagues reported that control measures such as isolation of cases and treatment with antivirals can work

During the spring of 2009, pandemic influenza A (H1N1) virus (pH1N1) was recognized and rapidly spread worldwide. To describe the geographic distribution and patient characteristics of pH1N1-associated deaths in the United States, the Centers for Disease Control and Prevention requested information from health departments on all laboratory-confirmed pH1N1 deaths reported from 17 April through 23 July 2009. Data were collected using medical charts, medical examiner reports, and death certificates. A total of 377 pH1N1-associated deaths were identified, for a mortality rate of .12 deaths per 100,000 population. Activity was geographically localized, with the highest mortality rates in Hawaii, New York, and Utah. Seventy-six percent of deaths occurred in persons aged 18-65 years, and 9% occurred in persons aged ≥ 65 years. Underlying medical conditions were reported for 78% of deaths: chronic lung disease among adults (39%) and neurologic disease among children (54%). Overall mortality associated with pH1N1 was low; however, the majority of deaths occurred in persons aged

The emergence in April 2009 and subsequent spread of the 2009 pandemic influenza A (H1N1) virus resulted in the first pandemic of the 21st century. This historic event was associated with unusual patterns of influenza activity in terms of the timing and persons affected in the United States throughout the summer and fall months of 2009 and the winter of 2010. The US Influenza Surveillance System identified 2 distinct waves of pandemic influenza H1N1 activity--the first peaking in June 2009, followed by a second peak in October 2009. All influenza surveillance components showed levels of influenza activity above that typically seen during late summer and early fall. During this period, influenza activity reached its highest level during the week ending 24 October 2009. This report summarizes US influenza surveillance data from 12 April 2009 through 27 March 2010.

To estimate the rates of hospitalization with seasonal influenza in children aged18 years from a large, diverse surveillance area during 2003 to 2008.Through the Emerging Infections Program Network, population-based surveillance for laboratory-confirmed influenza was conducted in 10 states, including 5.3 million children. Hospitalized children were identified retrospectively; clinicians made influenza testing decisions. Data collected from the hospital record included demographics, medical history, and clinical course. Incidence rates were calculated with census data.The highest hospitalization rates occurred in children aged6 months (seasonal range, 9-30/10 000 children), and the lowest rates occurred in children aged 5 to 17 years (0.3-0.8/10 000). Overall, 4015 children were hospitalized, 58% of whom were identified with rapid diagnostic tests alone. Forty percent of the children who were hospitalized had underlying medical conditions; asthma (18%), prematurity (15% of children aged2 years), and developmental delay (7%) were the most common. Severe outcomes included intensive care unit admission (12%), respiratory failure (5%), bacterial coinfection (2%), and death (0.5%).Influenza-associated hospitalization rates varied by season and age and likely underestimate true rates because many hospitalized children are not tested for influenza. The proportion of children with severe outcomes was substantial across seasons. Quantifying incidence of influenza hospitalization and severe outcomes is critical to defining disease burden.

Please cite this paper as: Peebles et al. (2010) Influenza-associated mortality among children – United States: 2007–2008. Influenza and Other Respiratory Viruses 5(1), 25–31. Background Since October 2004, pediatric influenza-associated deaths have been a nationally notifiable condition. To further investigate the bacterial organisms that may have contributed to death, we systematically collected information about bacterial cultures collected at non-sterile sites and about the timing of Staphylococcus aureus specimen collection relative to hospital admission. Methods We performed a retrospective, descriptive study of all reported influenza-associated pediatric deaths in 2007–2008 influenza season in the United States. Results During the 2007–2008 influenza season, 88 influenza-associated pediatric deaths were reported. The median age was 5 (range 29 days – 17 years); 48% were

Background Rates of influenza-associated hospitalizations in the United States have been estimated using modeling techniques with data from pneumonia and influenza hospitalization discharge diagnoses, but they have not been directly estimated from laboratory-positive cases. Methods We calculated overall, age-specific, and site-specific rates of laboratory-positive, influenza-associated hospitalization among adults and compared demographic and clinical characteristics and outcomes of hospitalized cases by season with use of data collected by the Emerging Infections Program Network during the 2005-2006 through 2007-2008 influenza seasons. Results Overall rates of adult influenza-associated hospitalization per 100,000 persons were 9.9 during the 2005-2006 season, 4.8 during the 2006-2007 season, and 18.7 during the 2007-2008 season. Rates of hospitalization varied by Emerging Infections Program site and increased with increasing age. Higher overall and age-specific rates of hospitalization were observed during influenza A (H3) predominant seasons and during periods of increased circulation of influenza B. More than 80% of hospitalized persons each season had > or =1 underlying medical condition, including chronic cardiovascular and metabolic diseases. Conclusions Rates varied by season, age, geographic location, and type/subtype of circulating influenza viruses. Influenza-associated hospitalization surveillance is essential for assessing the relative severity of influenza seasons over time and the burden of influenza-associated complications.

Pneumonia is one of the most common complications in children hospitalized with influenza. We describe hospitalized children with influenza-associated pneumonia and associated risk indicators.Through Emerging Infections Program Network population based surveillance, children aged18 years hospitalized with laboratory confirmed influenza with a chest radiograph during hospitalization were identified during the 2003-2008 influenza seasons. A case with radiologically confirmed influenza-associated pneumonia was defined as a child from the surveillance area hospitalized with: (1) laboratory-confirmed influenza and (2) evidence of new pneumonia on chest radiograph during hospitalization. Hospitalized children with pneumonia were compared with those without pneumonia by univariate and multivariate analysis.Overall, 2992 hospitalized children with influenza with a chest radiograph were identified; 1072 (36%) had influenza-associated pneumonia.When compared with children hospitalized with influenza without pneumonia, hospitalized children with influenza-associated pneumonia were more likely to require intensive care unit admission (21% vs. 11%, P0.01), develop respiratory failure (11% versus 3%, P0.01), and die(0.9% vs. 0.3% P 0.01). In multivariate analysis, age 6 to 23 months(adjusted OR: 2.1, CI: 1.6 -2.8), age 2 to 4 years (adjusted OR: 1.7, CI:1.3-2.2), and asthma (adjusted OR: 1.4, CI: 1.1-1.8) were significantly associated with influenza-associated pneumonia.Hospitalized children with influenza-associated pneumonia were more likely to have a severe clinical course than other hospitalized children with influenza, and children aged 6 months to 4 years and those with asthma were more likely to have influenza-associated pneumonia.Identifying children at greater risk for influenza-associated pneumonia will inform prevention and treatment strategies targeting children at risk for influenza complications.

To examine 2009 H1N1 influenza illness severity and the effect of antiviral treatment on the severity of illness among pregnant women.We abstracted medical records from hospitalized pregnant (n=62) and nonpregnant (n=74) women with laboratory-confirmed 2009 H1N1 influenza in New York City, May through June 2009. We compared characteristics of pregnant and nonpregnant women and of severe and moderate influenza illness among pregnant women, with severe defined as illness resulting in intensive care admission or death.The 2009 H1N1 hospitalization rate was significantly higher among pregnant than nonpregnant women (55.3 compared with 7.7 per 100,000 population). Eight pregnant (including two deaths) and 16 nonpregnant (including four deaths) cases were severe. Pregnant women represented 6.4% of hospitalized cases and 4.3% of deaths caused by 2009 H1N1 influenza. Only 1 in 30 (3.3%) pregnant women who received oseltamivir treatment within 2 days of symptom onset had severe illness compared with 3 of 14 (21.4%) and four of nine (44.4%) pregnant women who started treatment 3-4 days and 5 days or more after symptom onset, respectively (P=.002 for trend). Severe and moderate 2009 H1N1 influenza illness occurred in all pregnancy trimesters, but most women (54.8%) were in the third trimester. Twenty-two women delivered during their influenza hospitalization, and severe neonatal outcomes (neonatal intensive care unit admission or death) occurred among five of six (83.3%) women with severe illness compared with 2 of 16 (12.5%) women with moderate illness (P=.004).Our findings highlight the potential for severe illness and adverse neonatal outcomes among pregnant 2009 H1N1 influenza-infected women and suggest the benefit of early oseltamivir treatment.II.

As of June 11, 2009, a total of 17,855 probable or confirmed cases of 2009 pandemic influenza A (H1N1) had been reported in the United States. Risk factors for transmission remain largely uncharacterized. We characterize the risk factors and describe the transmission of the virus within households.Probable and confirmed cases of infection with the 2009 H1N1 virus in the United States were reported to the Centers for Disease Control and Prevention with the use of a standardized case form. We investigated transmission of infection in 216 households--including 216 index patients and their 600 household contacts--in which the index patient was the first case patient and complete information on symptoms and age was available for all household members.An acute respiratory illness developed in 78 of 600 household contacts (13%). In 156 households (72% of the 216 households), an acute respiratory illness developed in none of the household contacts; in 46 households (21%), illness developed in one contact; and in 14 households (6%), illness developed in more than one contact. The proportion of household contacts in whom acute respiratory illness developed decreased with the size of the household, from 28% in two-member households to 9% in six-member households. Household contacts 18 years of age or younger were twice as susceptible as those 19 to 50 years of age (relative susceptibility, 1.96; Bayesian 95% credible interval, 1.05 to 3.78; P=0.005), and household contacts older than 50 years of age were less susceptible than those who were 19 to 50 years of age (relative susceptibility, 0.17; 95% credible interval, 0.02 to 0.92; P=0.03). Infectivity did not vary with age. The mean time between the onset of symptoms in a case patient and the onset of symptoms in the household contacts infected by that patient was 2.6 days (95% credible interval, 2.2 to 3.5).The transmissibility of the 2009 H1N1 influenza virus in households is lower than that seen in past pandemics. Most transmissions occur soon before or after the onset of symptoms in a case patient.

SUMMARYStaphylococcus aureus is a relatively uncommon cause of community-onset pneumonia (COP) that may complicate influenza infection. We reviewed admissions to children's hospitals to describe more systematically this entity. Records of patients hospitalized at three children's hospitals between 1 October 2006 and 30 April 2007 who had a positive S. aureus culture from a sterile site or respiratory specimen were reviewed and data were abstracted for episodes of primary S. aureus COP. Overall, 30 episodes met criteria for primary S. aureus COP; 12 (41%) involved methicillin-resistant S. aureus. Patients in 11 (37%) episodes were seen by a healthcare provider for their symptoms prior to hospital admission; three received an antimicrobial, none of which had activity against the S. aureus isolated. Mechanical ventilation was required in 21 (70%) episodes; five (17%) patients died. When evaluating patients with severe COP, providers should be aware of the potential for S. aureus, including methicillin-resistant strains.

Through July 2009, a total of 43,677 laboratory-confirmed cases of influenza A pandemic (H1N1) 2009 were reported in the United States, which is likely a substantial underestimate of the true number. Correcting for under-ascertainment using a multiplier model, we estimate that 1.8 million-5.7 million cases occurred, including 9,000-21,000 hospitalizations.

Triple-reassortant swine influenza A (H1) viruses--containing genes from avian, human, and swine influenza viruses--emerged and became enzootic among pig herds in North America during the late 1990s.We report the clinical features of the first 11 sporadic cases of infection of humans with triple-reassortant swine influenza A (H1) viruses reported to the Centers for Disease Control and Prevention, occurring from December 2005 through February 2009, until just before the current epidemic of swine-origin influenza A (H1N1) among humans. These data were obtained from routine national influenza surveillance reports and from joint case investigations by public and animal health agencies.The median age of the 11 patients was 10 years (range, 16 months to 48 years), and 4 had underlying health conditions. Nine of the patients had had exposure to pigs, five through direct contact and four through visits to a location where pigs were present but without contact. In another patient, human-to-human transmission was suspected. The range of the incubation period, from the last known exposure to the onset of symptoms, was 3 to 9 days. Among the 10 patients with known clinical symptoms, symptoms included fever (in 90%), cough (in 100%), headache (in 60%), and diarrhea (in 30%). Complete blood counts were available for four patients, revealing leukopenia in two, lymphopenia in one, and thrombocytopenia in another. Four patients were hospitalized, two of whom underwent invasive mechanical ventilation. Four patients received oseltamivir, and all 11 recovered from their illness.From December 2005 until just before the current human epidemic of swine-origin influenza viruses, there was sporadic infection with triple-reassortant swine influenza A (H1) viruses in persons with exposure to pigs in the United States. Although all the patients recovered, severe illness of the lower respiratory tract and unusual influenza signs such as diarrhea were observed in some patients, including those who had been previously healthy.

Enhanced surveillance was implemented in the United States for human infection with influenza A viruses that could not be subtyped. Specimens were sent to the Centers for Disease Control and Prevention for real-time reverse-transcriptase–polymerase-chain-reaction confirmatory testing for S-OIV. RESULTS From April 15 through May 5, a total of 642 confirmed cases of S-OIV infection were identified in 41 states. The ages of patients ranged from 3 months to 81 years; 60% of patients were 18 years of age or younger. Of patients with available data, 18% had recently traveled to Mexico, and 16% were identified from school outbreaks of S-OIV infection. The most common presenting symptoms were fever (94% of patients), cough (92%), and sore throat (66%); 25% of patients had diarrhea, and 25% had vomiting. Of the 399 patients for whom hospitalization status was known, 36 (9%) required hospitalization. Of 22 hospitalized patients with available data, 12 had characteristics that conferred an increased risk of severe seasonal influenza, 11 had pneumonia, 8 required admission to an intensive care unit, 4 had respiratory failure, and 2 died. The S-OIV was determined to have a unique genome composition that had not been identified previously. CONCLUSIONS A novel swine-origin influenza A virus was identified as the cause of outbreaks of febrile respiratory infection ranging from self-limited to severe illness. It is likely that the number of confirmed cases underestimates the number of cases that have occurred.

Generation of Swine Flu As the newly emerged influenza virus starts its journey to infect the world's human population, the genetic secrets of the 2009 outbreak of swine influenza A(H1N1) are being revealed. In extensive phylogenetic analyses, Garten et al. (p. 197 , published online 22 May) confirm that of the eight elements of the virus, the basic components encoded by the hemagglutinin, nucleoprotein, and nonstructural genes originated in birds and transferred to pigs in 1918. Subsequently, these formed a triple reassortant with the RNA polymerase PB1 that transferred from birds in 1968 to humans and then to pigs in 1998, coupled with RNA polymerases PA and PB2 that transferred from birds to pigs in 1998. The neuraminidase and matrix protein genes that complete the virus came from birds and entered pigs in 1979. The analysis offers insights into drug susceptibility and virulence, as well as raising the possibility of hitherto unknown factors determining host specificity. A significant question is, what is the potential for the H1 component of the current seasonal flu vaccine to act as a booster? Apart from the need for ongoing sequencing to monitor for the emergence of new reassortants, future pig populations need to be closely monitored for emerging influenza viruses.

BACKGROUND Since the mid-1990s, hepatitis A vaccine has been recommended for US children living in historically high-incidence states and for persons with other risk factors or chronic liver disease (CLD). The incidence of hepatitis A has declined dramatically during the era of vaccination, but trends in mortality are largely unknown. METHODS US death certificates from 1990 to 2004 for which hepatitis A was listed as the underlying cause of death were analyzed. Average annual age-adjusted mortality rates during the prevaccine (1990-1995) and post-vaccination recommendation (2000-2004) periods were compared using a Mantel-Haenszel test of association. The number of deaths for which CLD was listed as a contributing cause was determined. RESULTS Overall, 1436 deaths due to hepatitis A occurred, averaging 96 annually (range, 142 in 1995 to 54 in 2003). CLD contributed to nearly half of these deaths. Mortality rates paralleled incidence rates, beginning to decline in the mid-1990s and achieving low points in 2003 and 2004. Average rates were 32% lower in the post-vaccination recommendation period than in the prevaccine period (P < .01). The decline was more dramatic for states with (45%; P < .001) than without (23%; P = .002) recommendations. CONCLUSIONS Hepatitis A mortality rates have declined over the past decade. CLD remains an important and preventable contributing cause of death due to hepatitis A.

Background Influenza vaccines are now widely used to reduce the burden of annual epidemics of influenza virus infections. Influenza vaccine effectiveness (VE) is monitored annually to determine VE against each season's circulating influenza strains in different groups such as children, adults and the elderly. Few prospective surveillance programs are available to evaluate influenza VE against medically attended illness for patients of all ages in the United States. Methods We conducted surveillance of patients with acute respiratory illnesses in 101 clinics across the US during three consecutive influenza seasons. We analyzed laboratory testing results for influenza virus, self-reported vaccine history, and patient characteristics, defining cases as patients who tested positive for influenza virus and controls as patients who tested negative for influenza virus. Comparison of influenza vaccination coverage among cases versus controls, adjusted for potential confounders, was used to estimate VE as one minus the adjusted odds ratio multiplied by 100%. Results We included 10,650 patients during three influenza seasons from August 2010 through December 2013, and estimated influenza VE in children 6m–5y of age (58%; 95% CI: 49%–66%), children 6–17y (45%; 95% CI: 34%–53%), adults 18–49y (36%; 95% CI: 24%, 46%), and adults ≥50y (34%, 95% CI: 13%, 51%). VE was higher against influenza A(H1N1) compared to A(H3N2) and B. Conclusions Our estimates of moderate influenza VE confirm the important role of vaccination in protecting against medically attended influenza virus infection.

To describe and compare the clinical characteristics, outcomes, and etiology of pneumonia among children hospitalized with community-acquired pneumonia (CAP) with neurologic disorders, non-neurologic underlying conditions, and no underlying conditions.Children18 years old hospitalized with clinical and radiographic CAP were enrolled at 3 US children's hospitals. Neurologic disorders included cerebral palsy, developmental delay, Down syndrome, epilepsy, non-Down syndrome chromosomal abnormalities, and spinal cord abnormalities. We compared the epidemiology, etiology, and clinical outcomes of CAP in children with neurologic disorders with those with non-neurologic underlying conditions, and those with no underlying conditions using bivariate, age-stratified, and multivariate logistic regression analyses.From January 2010-June 2012, 2358 children with radiographically confirmed CAP were enrolled; 280 (11.9%) had a neurologic disorder (52.1% of these individuals also had non-neurologic underlying conditions), 934 (39.6%) had non-neurologic underlying conditions only, and 1144 (48.5%) had no underlying conditions. Children with neurologic disorders were older and more likely to require intensive care unit (ICU) admission than children with non-neurologic underlying conditions and children with no underlying conditions; similar proportions were mechanically ventilated. In age-stratified analysis, children with neurologic disorders were less likely to have a pathogen detected than children with non-neurologic underlying conditions. In multivariate analysis, having a neurologic disorder was associated with ICU admission for children ≥2 years of age.Children with neurologic disorders hospitalized with CAP were less likely to have a pathogen detected and more likely to be admitted to the ICU than children without neurologic disorders.

Background. Some studies suggest that influenza vaccination might be protective against severe influenza outcomes in vaccinated persons who become infected. We used data from a large surveillance network to further investigate the effect of influenza vaccination on influenza severity in adults aged ≥50 years who were hospitalized with laboratory-confirmed influenza. Methods. We analyzed influenza vaccination and influenza severity using Influenza Hospitalization Surveillance Network (FluSurv-NET) data for the 2012−2013 influenza season. Intensive care unit (ICU) admission, death, diagnosis of pneumonia, and hospital and ICU lengths of stay served as measures of disease severity. Data were analyzed by multivariable logistic regression, parametric survival models, and propensity score matching (PSM). Results. Overall, no differences in severity were observed in the multivariable logistic regression model. Using PSM, adults aged 50−64 years (but not other age groups) who were vaccinated against influenza had a shorter length of ICU stay than those who were unvaccinated (hazard ratio for discharge, 1.84; 95% confidence interval, 1.12−3.01). Conclusions. Our findings show a modest effect of influenza vaccination on disease severity. Analysis of data from seasons with different predominant strains and higher estimates of vaccine effectiveness are needed.

Background Influenza and pneumonia combined are the leading causes of death due to infectious diseases in the United States. We describe factors associated with pneumonia among adults hospitalized with influenza. Methods Through the Emerging Infections Program, we identified adults ≥ 18 years, who were hospitalized with laboratory-confirmed influenza during October 2005 through April 2008, and had a chest radiograph (CXR) performed. Pneumonia was defined as the presence of a CXR infiltrate and either an ICD-9-CM code or discharge summary diagnosis of pneumonia. Results Among 4,765 adults hospitalized with influenza, 1392 (29 %) had pneumonia. In multivariable analysis, factors associated with pneumonia included: age ≥ 75 years, adjusted odds ratio (AOR) 1.27 (95 % confidence interval 1.10–1.46), white race AOR 1.24 (1.03–1.49), nursing home residence AOR 1.37 (1.14–1.66), chronic lung disease AOR 1.37 (1.18–1.59), immunosuppression AOR 1.45 (1.19–1.78), and asthma AOR 0.76 (0.62–0.92). Patients with pneumonia were significantly more likely to require intensive care unit (ICU) admission (27 % vs. 10 %), mechanical ventilation (18 % vs. 5 %), and to die (9 % vs. 2 %). Conclusions Pneumonia was present in nearly one-third of adults hospitalized with influenza and was associated with ICU admission and death. Among patients hospitalized with influenza, older patients and those with certain underlying conditions are more likely to have pneumonia. Pneumonia is common among adults hospitalized with influenza and should be evaluated and treated promptly. Electronic supplementary material The online version of this article (doi:10.1186/s12879-015-1004-y) contains supplementary material, which is available to authorized users.

Summary Background Since the introduction of pandemic influenza A (H1N1) to the USA in 2009, the Influenza Incidence Surveillance Project has monitored the burden of influenza in the outpatient setting through population-based surveillance. Methods From Oct 1, 2009, to July 31, 2013, outpatient clinics representing 13 health jurisdictions in the USA reported counts of influenza-like illness (fever including cough or sore throat) and all patient visits by age. During four years, staff at 104 unique clinics (range 35–64 per year) with a combined median population of 368 559 (IQR 352 595–428 286) attended 35 663 patients with influenza-like illness and collected 13 925 respiratory specimens. Clinical data and a respiratory specimen for influenza testing by RT-PCR were collected from the first ten patients presenting with influenza-like illness each week. We calculated the incidence of visits for influenza-like illness using the size of the patient population, and the incidence attributable to influenza was extrapolated from the proportion of patients with positive tests each week. Findings The site-median peak percentage of specimens positive for influenza ranged from 58·3% to 77·8%. Children aged 2 to 17 years had the highest incidence of influenza-associated visits (range 4·2–28·0 per 1000 people by year), and adults older than 65 years had the lowest (range 0·5–3·5 per 1000 population). Influenza A H3N2, pandemic H1N1, and influenza B equally co-circulated in the first post-pandemic season, whereas H3N2 predominated for the next two seasons. Of patients for whom data was available, influenza vaccination was reported in 3289 (28·7%) of 11 459 patients with influenza-like illness, and antivirals were prescribed to 1644 (13·8%) of 11 953 patients. Interpretation Influenza incidence varied with age groups and by season after the pandemic of 2009 influenza A H1N1. High levels of influenza virus circulation, especially in young children, emphasise the need for additional efforts to increase the uptake of influenza vaccines and antivirals. Funding US Centers for Disease Control and Prevention.

Community-acquired pneumonia is a leading infectious cause of hospitalization and death among U.S. adults. Incidence estimates of pneumonia confirmed radiographically and with the use of current laboratory diagnostic tests are needed.We conducted active population-based surveillance for community-acquired pneumonia requiring hospitalization among adults 18 years of age or older in five hospitals in Chicago and Nashville. Patients with recent hospitalization or severe immunosuppression were excluded. Blood, urine, and respiratory specimens were systematically collected for culture, serologic testing, antigen detection, and molecular diagnostic testing. Study radiologists independently reviewed chest radiographs. We calculated population-based incidence rates of community-acquired pneumonia requiring hospitalization according to age and pathogen.From January 2010 through June 2012, we enrolled 2488 of 3634 eligible adults (68%). Among 2320 adults with radiographic evidence of pneumonia (93%), the median age of the patients was 57 years (interquartile range, 46 to 71); 498 patients (21%) required intensive care, and 52 (2%) died. Among 2259 patients who had radiographic evidence of pneumonia and specimens available for both bacterial and viral testing, a pathogen was detected in 853 (38%): one or more viruses in 530 (23%), bacteria in 247 (11%), bacterial and viral pathogens in 59 (3%), and a fungal or mycobacterial pathogen in 17 (1%). The most common pathogens were human rhinovirus (in 9% of patients), influenza virus (in 6%), and Streptococcus pneumoniae (in 5%). The annual incidence of pneumonia was 24.8 cases (95% confidence interval, 23.5 to 26.1) per 10,000 adults, with the highest rates among adults 65 to 79 years of age (63.0 cases per 10,000 adults) and those 80 years of age or older (164.3 cases per 10,000 adults). For each pathogen, the incidence increased with age.The incidence of community-acquired pneumonia requiring hospitalization was highest among the oldest adults. Despite current diagnostic tests, no pathogen was detected in the majority of patients. Respiratory viruses were detected more frequently than bacteria. (Funded by the Influenza Division of the National Center for Immunizations and Respiratory Diseases.).

Influenza activity in the United States began to increase in mid-November, remained elevated through February 21, 2015, and is expected to continue for several more weeks. To date, influenza A (H3N2) viruses have predominated overall. As has been observed in previous seasons during which influenza A (H3N2) viruses predominated, adults aged ≥65 years have been most severely affected. The cumulative laboratory-confirmed influenza-associated hospitalization rate among adults aged ≥65 years is the highest recorded since this type of surveillance began in 2005. This age group also accounts for the majority of deaths attributed to pneumonia and influenza. The majority of circulating influenza A (H3N2) viruses are different from the influenza A (H3N2) component of the 2014-15 Northern Hemisphere seasonal vaccines, and the predominance of these antigenically and genetically drifted viruses has resulted in reduced vaccine effectiveness. This report summarizes U.S. influenza activity* since September 28, 2014, and updates the previous summary.

Novel data streams (NDS), such as web search data or social media updates, hold promise for enhancing the capabilities of public health surveillance. In this paper, we outline a conceptual framework for integrating NDS into current public health surveillance. Our approach focuses on two key questions: What are the opportunities for using NDS and what are the minimal tests of validity and utility that must be applied when using NDS? Identifying these opportunities will necessitate the involvement of public health authorities and an appreciation of the diversity of objectives and scales across agencies at different levels (local, state, national, international). We present the case that clearly articulating surveillance objectives and systematically evaluating NDS and comparing the performance of NDS to existing surveillance data and alternative NDS data is critical and has not sufficiently been addressed in many applications of NDS currently in the literature.

Hepatitis C virus (HCV) is a major cause of liver disease worldwide and a potential cause of substantial morbidity and mortality in the future. The complexity and uncertainty related to the geographic distribution of HCV infection and chronic hepatitis C, determination of its associated risk factors, and evaluation of cofactors that accelerate its progression, underscore the difficulties in global prevention and control of HCV. Because there is no vaccine and no post-exposure prophylaxis for HCV, the focus of primary prevention efforts should be safer blood supply in the developing world, safe injection practices in health care and other settings, and decreasing the number of people who initiate injection drug use.

In December 2002, all U.S. chronic hemodialysis centers were surveyed regarding selected patient care practices and dialysis-associated diseases. The results were compared with similar surveys conducted in previous years. In 2002, 85% of hemodialysis centers were free-standing and 81% operated for profit; the proportion of centers operating for profit has increased each year since 1985. During 1995-2002, the percentage of patients who received dialysis through central catheters increased from 13% to 26%; this trend is worrisome, as infections and antimicrobial use are higher among patients receiving dialysis through catheters. However, during the same period, the percentage of patients receiving dialysis through fistulas increased from 22% to 33%. The percentage of centers reporting one or more patients infected or colonized with vancomycin-resistant enterococci (VRE) increased from 12% in 1995 to 30% in 2002. During 1997-2002, the percentage of patients vaccinated against hepatitis B virus (HBV) infection increased from 47% to 56% and the percentage of staff vaccinated increased from 87% to 90%. In 2002, routine testing for antibody to hepatitis C virus (anti-HCV) was performed on patients at 64% of centers; anti-HCV was found in 7.8% of patients. In 2001, the Centers for Disease Control (CDC) published Recommendations for Preventing Transmission of Infections among Chronic Hemodialysis Patients. Centers were surveyed regarding their awareness of the recommendations and about a variety of infection control practices. In general, the incidence of HBV and HCV was not substantially different for the infection control practices evaluated, including where staff obtain clean supplies for patient treatment, reuse of unused and unopened supplies, and practices for changing external transducer filters/protectors. However, in 2002, the incidence of HBV infection was higher among patients in centers where injectable medications were prepared on a medication cart or medication area located in the treatment area compared to a dedicated medication room. Also, those centers that used a disposable container versus a nondisposable container for priming the dialyzer had a significantly lower incidence of HCV.

In December 2001, all U.S. chronic hemodialysis (HD) centers were surveyed regarding selected patient care practices and dialysis-associated diseases. The results were compared with similar surveys conducted in previous years. During 1997–2001, the percentage of patients vaccinated against hepatitis B virus (HBV) infection increased from 47% to 60% and the percentage of staff vaccinated increased from 87% to 89%. In 2001, an estimated 65% of patients had been vaccinated for influenza and 26% for pneumococcal pneumonia. In 2001, routine testing for antibody to hepatitis C virus (anti-HCV) was performed on staff at 42% of centers and on patients at 62% of centers; anti-HCV was found in 1.5% of staff and 8.6% of patients. In 2001, the incidence of HBV infection was higher among patients in centers where injectable medications were prepared at the dialysis station, and both HCV prevalence and incidence were higher among patients in centers where injectable medications were prepared at the dialysis station compared to a dedicated medication room. During 1995–2001, the percentage of patients who received dialysis through central catheters increased from 13% to 25%; this trend is worrisome, as infections and antimicrobial use are higher among patients receiving dialysis through catheters. However, during the same period, the percentage of patients receiving dialysis through fistulas increased from 22% to 30%. In 2001, 25% of catheters were used for new patients awaiting an arteriovenous (AV) access, 28% for established patients with a failed access awaiting new AV access, 40% as an access of last resort, and 6% for other reasons, including patient preference. The percentage of centers reporting one or more patients infected or colonized with vancomycin-resistant enterococcus (VRE) increased from 12% in 1995 to 31% in 2001.

Background: Syphilis seroprevalence data can be used as an independent measure of syphilis trends and to augment syphilis case report data for program planning. The prevalence of reactive syphilis serology in jails, delivery rooms, and drug treatment centers was examined from 1995 to 1999. Prevalence was evaluated by age and gender at each site and compared with county primary and secondary syphilis case rates. Annual prevalence of high titer-reactive serology in jails was compared with primary and secondary syphilis case rates. Goal: The goal was to examine trends in syphilis seroprevalence and to evaluate the relationship of trends in seroprevalence to reported cases. Study Design: This was a cross-sectional survey. Results: Prevalence of reactive serology and high titer-reactive serology was lowest among women in delivery rooms (2.9% and 0.4%, respectively) and highest among women in jails (11.1% and 4.1%, respectively), indicating substantial recently treated or active infection among women in jails. Trends in high titer-reactive serology were similar to primary and secondary syphilis case rates. Conclusion: The prevalence of high titer-reactive serology can provide valuable information about community syphilis morbidity for use in prevention and control programs.

In April, 2009, CDC identified a novel influenza A virus detected from 2 children with febrile respiratory illness in southern California. The virus quickly emerged and spread globally and by 5 May, confirmed cases had been reported from 41 US states and 21 countries worldwide. Since the virus had never been identified before, little was known about the characteristics of the virus and how the pandemic would progress-would it be severe, how efficient would viral transmission be, would transmission be sustainable, what would the spectrum of illness, factors associated with severe disease, and causes of death be, and what risk groups would be most affected? Field investigations and epidemiologic studies in the United States and elsewhere were critical in helping answer these questions and characterizing the virus and the pandemic. This supplement will report results from field and epidemiologic investigations conducted in the United States since April 2009.

The Advisory Committee on Immunization Practices recommends annual influenza vaccination for all persons aged ≥6 months to reduce morbidity and mortality caused by influenza in the United States. CDC previously developed a model to estimate that annual influenza vaccination resulted in 1.1-6.6 million fewer cases and 7,700-79,000 fewer hospitalizations per season during the 2005-2013 influenza seasons. For the 2013-14 influenza season, using updated estimates of vaccination coverage, vaccine effectiveness, and influenza hospitalizations, CDC estimates that influenza vaccination prevented approximately 7.2 million illnesses, 3.1 million medically attended illnesses, and 90,000 hospitalizations associated with influenza. Similar to prior seasons, fewer than half of persons aged ≥6 months are estimated to have been vaccinated. If influenza vaccination levels had reached the Healthy People 2020 target of 70%, an estimated additional 5.9 million illnesses, 2.3 million medically attended illnesses, and 42,000 hospitalizations associated with influenza might have been averted. For the nation to more fully benefit from influenza vaccines, more effort is needed to reach the Healthy People 2020 target.

During May 18-September 20, 2014, the United States experienced low levels of seasonal influenza activity overall. Influenza A (H1N1)pdm09 (pH1N1), influenza A (H3N2), and influenza B viruses were detected worldwide and were identified sporadically in the United States. In August, two influenza A (H3N2) variant viruses (H3N2v) were detected in Ohio. This report summarizes influenza activity in the United States and worldwide during May 18-September 20, 2014.

Annual estimates of the influenza disease burden provide information to evaluate programs and allocate resources. We used a multiplier method with routine population-based surveillance data on influenza hospitalization in the United States to correct for under-reporting and estimate the burden of influenza for seasons after the 2009 pandemic. Five sites of the Influenza Hospitalization Surveillance Network (FluSurv-NET) collected data on the frequency and sensitivity of influenza testing during two seasons to estimate under-detection. Population-based rates of influenza-associated hospitalization and Intensive Care Unit admission from 2010-2013 were extrapolated to the U.S. population from FluSurv-NET and corrected for under-detection. Influenza deaths were calculated using a ratio of deaths to hospitalizations. We estimated that influenza-related hospitalizations were under-detected during 2010-11 by a factor of 2.1 (95%CI 1.7-2.9) for age < 18 years, 3.1 (2.4-4.5) for ages 18-64 years, and 5.2 (95%CI 3.8-8.3) for age 65+. Results were similar in 2011-12. Extrapolated estimates for 3 seasons from 2010-2013 included: 114,192-624,435 hospitalizations, 18,491-95,390 ICU admissions, and 4,915-27,174 deaths per year; 54-70% of hospitalizations and 71-85% of deaths occurred among adults aged 65+. Influenza causes a substantial disease burden in the U.S. that varies by age and season. Periodic estimation of multipliers across multiple sites and age groups improves our understanding of influenza detection in sentinel surveillance systems. Adjusting surveillance data using a multiplier method is a relatively simple means to estimate the impact of influenza and the subsequent value of interventions to prevent influenza.

Background The potential impact of an influenza pandemic can be assessed by calculating a set of transmissibility parameters, the most important being the reproduction number (R), which is defined as the average number of secondary cases generated per typical infectious case. Methods We conducted a systematic review to summarize published estimates of R for pandemic or seasonal influenza and for novel influenza viruses (e.g. H5N1). We retained and summarized papers that estimated R for pandemic or seasonal influenza or for human infections with novel influenza viruses. Results The search yielded 567 papers. Ninety-one papers were retained, and an additional twenty papers were identified from the references of the retained papers. Twenty-four studies reported 51 R values for the 1918 pandemic. The median R value for 1918 was 1.80 (interquartile range [IQR]: 1.47–2.27). Six studies reported seven 1957 pandemic R values. The median R value for 1957 was 1.65 (IQR: 1.53–1.70). Four studies reported seven 1968 pandemic R values. The median R value for 1968 was 1.80 (IQR: 1.56–1.85). Fifty-seven studies reported 78 2009 pandemic R values. The median R value for 2009 was 1.46 (IQR: 1.30–1.70) and was similar across the two waves of illness: 1.46 for the first wave and 1.48 for the second wave. Twenty-four studies reported 47 seasonal epidemic R values. The median R value for seasonal influenza was 1.28 (IQR: 1.19–1.37). Four studies reported six novel influenza R values. Four out of six R values were

Background Seasonal influenza causes considerable morbidity and mortality across all age groups, and influenza vaccination was recommended in 2010 for all persons aged 6 months and above. We estimated the averted costs due to influenza vaccination, taking into account the seasonal economic burden of the disease. Methods We used recently published values for averted outcomes due to influenza vaccination for influenza seasons 2005-06, 2006-07, 2007-08, and 2008-09, and age cohorts 6 months-4 years, 5-19 years, 20-64 years, and 65 years and above. Costs were calculated according to a payer and societal perspective (in 2009 US$), and took into account medical costs and productivity losses. Results When taking into account direct medical costs (payer perspective), influenza vaccination was cost saving only for the older age group (65≥) in seasons 2005-06 and 2007-08. Using the same perspective, influenza vaccination resulted in total costs of $US 1.7 billion (95%CI: $US 0.3–4.0 billion) in 2006-07 and $US 1.8 billion (95%CI: $US 0.1–4.1 billion) in 2008-09. When taking into account a societal perspective (and including the averted lost earnings due to premature death) averted deaths in the older age group influenced the results, resulting in cost savings for all ages combined in season 07-08. Discussion Influenza vaccination was cost saving in the older age group (65≥) when taking into account productivity losses and, in some seasons, when taking into account medical costs only. Averted costs vary significantly per season; however, in seasons where the averted burden of deaths is high in the older age group, averted productivity losses due to premature death tilt overall seasonal results towards savings. Indirect vaccination effects and the possibility of diminished case severity due to influenza vaccination were not considered, thus the averted burden due to influenza vaccine may be even greater than reported.

Influenza viruses cause substantial morbidity in children each year, especially among children with specific chronic conditions. In particular, neurologic disorders have emerged as a strong risk factor for influenza-related complications. Children with these disorders may be vulnerable due to diminished respiratory muscle strength, decreased muscle tone or impaired mobility, which can compromise pulmonary function and the ability to handle secretions. Although they represent a small fraction of the general pediatric population, children with neurologic disorders make up a disproportionately high number of those children who are hospitalized and die as a result of influenza-associated complications. Annual vaccination is the most effective way to prevent influenza and its complications, and is recommended for all children 6 months through 18 years of age, including children with neurologic disorders. Family members and those who work with these children in institutional, educational and daycare settings should also be vaccinated against influenza annually. However, there have been few studies of influenza vaccination specifically in this population. In addition, vaccine effectiveness may vary from year to year and vaccination will not prevent all infections. Early empiric antiviral treatment should be started promptly in these children if they present to healthcare providers with symptoms suspicious for influenza. This article reviews influenza epidemiology in children with neurologic disorders and what is known about vaccines and other methods of protecting this vulnerable population from influenza-related complications.

We compared influenza vaccine-prevented hospitalizations in adults aged ≥65 years for a range of hypothetical effectiveness estimates. During 2012-2013, a vaccine with 10% effectiveness (66% coverage) would have averted approximately 13 000 hospitalizations, and a vaccine with 40% effectiveness would have averted approximately 60 000 hospitalizations. Annual vaccination is merited in this vulnerable population.

Influenza activity in the United States began to increase in mid-November and remained elevated through February 8, 2014. During that time, influenza A (H1N1)pdm09 (pH1N1) viruses predominated overall, while few B and A (H3N2) viruses were detected. This report summarizes U.S. influenza activity* during September 29, 2013-February 8, 2014, and updates the previous summary.

A molecular-based subtyping system for Treponema pallidum was used during an investigation of increasing syphilis in Maricopa County, Arizona. Genital ulcer or whole blood specimens from patients with syphilis were assayed by a polymerase chain reaction (PCR) amplification of a T. pallidum DNA polymerase I gene. Positive specimens were typed on the basis of PCR amplification of 2 variable genes. In all, 41 (93%) of 44 of ulcer specimens and 4 (27%) of 15 blood specimens yielded typeable T. pallidum DNA. Twenty-four (53%) of 45 specimens were subtype 14f; other subtypes identified included 4f, 4i, 5f, 12a, 12f, 14a, 14d, 14e, and 14i. Only 2 specimens were from epidemiologically linked patients. This investigation demonstrates that multiple subtypes of T. pallidum can be found in an area with high syphilis morbidity, although 1 subtype (14f) was predominant. Four typeable specimens were from blood, a newly identified specimen source for subtyping.

Syphilis rates began to decline in 1991 and have decreased every year since. In 1998, 6,993 cases of primary and secondary syphilis were reported in the United States, for a national incidence of 2.6 cases per 100,000 population. Although syphilis rates are at an historic low, focal outbreaks still occur. On October 7, 1999, the Division of Sexually Transmitted Disease Prevention of the Centers for Disease Control and Prevention, in collaboration with federal and community partners, presented the National Plan for Elimination of Syphilis from the United States. One of the five key strategies of the plan is rapid outbreak response.Methods for outbreak assessment and response were reviewed in the literature, synthesized, and adapted for use in syphilis outbreaks.Key elements of outbreak assessment and response are detection, surveillance data review, hypothesis generation, intervention development, and the evaluation of clinical, public health, and laboratory services.Outbreak response necessitates community participation and a coordinated interdisciplinary effort to determine social and behavioral contributors to the outbreak and to develop targeted interventions.

Respiratory syncytial virus (RSV) infection might facilitate bacterial infection. We describe 5 patients with RSV among 30 children admitted to pediatric hospitals in Atlanta between October 1, 2006 and April 30, 2007 with community-onset Staphylococcus aureus pneumonia. RSV-S. aureus patients were younger and had less medical comorbidity than those without RSV.