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For editorial comment see p 772. Context Concerns about rates of methicillin-resistant Staphylococcus aureus (MRSA) health care-associated infections have prompted calls for mandatory screening or reporting in efforts to reduce MRSA infections. Objective To examine trends in the incidence of MRSA central line-associated bloodstream infections (BSIs) in US intensive care units (ICUs). Design, Setting, and Participants Data reported by hospitals to the Centers for Disease Control and Prevention (CDC) from 1997-2007 were used to calculate pooled mean annual central line-associated BSI incidence rates for 7 types of adult and nonneonatal pediatric ICUs. Percent MRSA was defined as the proportion of S aureus central line-associated BSIs that were MRSA. We used regression modeling to estimate percent changes in central line-associated BSI metrics over the analysis period. Main Outcome Measures Incidence rate of central line-associated BSIs per 1000 central line days; percent MRSA among S aureus central line-associated BSIs. Results Overall, 33 587 central line-associated BSIs were reported from 1684 ICUs representing 16 225 498 patient-days of surveillance; 2498 reported central line-associated BSIs (7.4%) were MRSA and 1590 (4.7%) were methicillin-susceptible S aureus (MSSA). Of evaluated ICU types, surgical, nonteaching-affiliated medical-surgical, cardiothoracic, and coronary units experienced increases in MRSA central line-associated BSI incidence in the 1997-2001 period; however, medical, teaching-affiliated medicalsurgical, and pediatric units experienced no significant changes. From 2001 through 2007, MRSA central line-associated BSI incidence declined significantly in all ICU types except in pediatric units, for which incidence rates remained static. Declines in MRSA central lineassociated BSI incidence ranged from −51.5% (95% CI, −33.7% to −64.6%; PϽ.001) in nonteaching-affiliated medical-surgical ICUs (0.31 vs 0.15 per 1000 central line days) to −69.2% (95% CI, −57.9% to −77.7%; PϽ.001) in surgical ICUs (0.58 vs 0.18 per 1000 central line days). In all ICU types, MSSA central line-associated BSI incidence declined from 1997 through 2007, with changes in incidence ranging from −60.1% (95% CI, −41.2% to −73.1%; PϽ.001) in surgical ICUs (0.24 vs 0.10 per 1000 central line days) to −77.7% (95% CI, −68.2% to −84.4%; PϽ.001) in medical ICUs (0.40 vs 0.09 per 1000 central line days). Although the overall proportion of S aureus central lineassociated BSIs due to MRSA increased 25.8% (P=.02) in the 1997-2007 period, overall MRSA central line-associated BSI incidence decreased 49.6% (PϽ.001) over this period. Conclusions The incidence of MRSA central line-associated BSI has been decreasing in recent years in most ICU types reporting to the CDC. These trends are not apparent when only percent MRSA is monitored.

Community surveys of healthcare-use determine the proportion of illness episodes not captured by health facility-based surveillance, the methodology used most commonly to estimate the burden of disease in Africa. A cross-sectional survey of households with children aged less than five years was conducted in 35 of 686 census enumeration areas in rural Bondo district, western Kenya. Healthcare sought for acute episodes of diarrhoea or fever in the past two weeks or pneumonia in the past year was evaluated. Factors associa-ted with healthcare-seeking were analyzed by logistic regression accounting for sample design. In total, 6,223 residents of 981 households were interviewed. Of 1,679 children aged less than five years, 233 (14%) had diarrhoea, and 736 (44%) had fever during the past two weeks; care at health facilities was sought for one-third of these episodes. Pneumonia in the past year was reported for 64 (4%) children aged less than five years; 88% sought healthcare at any health facility and 48% at hospitals. Seeking healthcare at health facilities was more likely for children from households with higher socioeconomic status and with more symptoms of severe illness. Health facility and hospital-based surveillance would underestimate the burden of disease substantially in rural western Kenya. Seeking healthcare at health facilities and hospitals varied by syndrome, severity of illness, and characteristics of the patient.

Further understanding of RSV seasonality in developing countries and various climate regions will be important to better understand the epidemiology of RSV and for timing the use of future RSV vaccines and immunoprophylaxis in low- and middle-income countries.

BackgroundThe epidemiology of non-Typhi Salmonella (NTS) bacteremia in Africa will likely evolve as potential co-factors, such as HIV, malaria, and urbanization, also change.MethodsAs part of population-based surveillance among 55,000 persons in malaria-endemic, rural and malaria-nonendemic, urban Kenya from 2006–2009, blood cultures were obtained from patients presenting to referral clinics with fever ≥38.0°C or severe acute respiratory infection. Incidence rates were adjusted based on persons with compatible illnesses, but whose blood was not cultured.ResultsNTS accounted for 60/155 (39%) of blood culture isolates in the rural and 7/230 (3%) in the urban sites. The adjusted incidence in the rural site was 568/100,000 person-years, and the urban site was 51/100,000 person-years. In both sites, the incidence was highest in children <5 years old. The NTS-to-typhoid bacteremia ratio in the rural site was 4.6 and in the urban site was 0.05. S. Typhimurium represented >85% of blood NTS isolates in both sites, but only 21% (urban) and 64% (rural) of stool NTS isolates. Overall, 76% of S. Typhimurium blood isolates were multi-drug resistant, most of which had an identical profile in Pulse Field Gel Electrophoresis. In the rural site, the incidence of NTS bacteremia increased during the study period, concomitant with rising malaria prevalence (monthly correlation of malaria positive blood smears and NTS bacteremia cases, Spearman's correlation, p = 0.018 for children, p = 0.16 adults). In the rural site, 80% of adults with NTS bacteremia were HIV-infected. Six of 7 deaths within 90 days of NTS bacteremia had HIV/AIDS as the primary cause of death assigned on verbal autopsy.ConclusionsNTS caused the majority of bacteremias in rural Kenya, but typhoid predominated in urban Kenya, which most likely reflects differences in malaria endemicity. Control measures for malaria, as well as HIV, will likely decrease the burden of NTS bacteremia in Africa.