High Prevalence of Shigella or Enteroinvasive Escherichia coli Carriage among Residents of an Internally Displaced Persons Camp in South Sudan.

Displaced persons living in camps are at an increased risk of diarrheal diseases. Subclinical carriage of pathogens may contribute to the spread of disease, especially for microbes that require a low infectious dose. Multiplex real-time polymerase chain reaction was performed to detect a panel of 20 bacterial, viral, and protozoal targets, and we report a high prevalence of enteropathogen carriage, including Shigella spp. or enteroinvasive Escherichia coli in 14%, among a sample of 88 asymptomatic individuals in an internally displaced persons camp in South Sudan. Further studies are needed to determine the contribution of such carriage to the spread of disease.

Expanded Geographic Distribution and Clinical Characteristics of Ehrlichia ewingii Infections, United States.

Ehrlichiosis is a bacterial zoonosis, spread through the bites of infected ticks, that is most commonly caused in the United States by infection with the bacterium Ehrlichia chaffeensis. We retrospectively reviewed samples from an 18-month study of ehrlichiosis in the United States and found that E. ewingii was present in 10 (9.2%) of 109 case-patients with ehrlichiosis, a higher rate of infection with this species than had previously been reported. Two patients resided in New Jersey and Indiana, where cases have not been reported. All patients with available case histories recovered. Our study suggests a higher prevalence and wider geographic distribution of E. ewingii in the United States than previous reports have indicated.

Clinical and Analytical Evaluation of a Single-Vial Stool Collection Device with Formalin-Free Fixative for Improved Processing and Comprehensive Detection of Gastrointestinal Parasites.

Microscopic examination of feces is a standard laboratory method for diagnosing gastrointestinal parasite infections. In North America, the ovum and parasite (O&P) examination is typically performed using stool that is chemically fixed in polyvinyl alcohol (PVA) and formalin, after which the stool is concentrated by filtration to enhance sensitivity. Mini Parasep solvent-free (SF) tubes allow collection and concentration within a single collection vial. The goal of the study was to determine whether consolidated processing and concentration with the Parasep tubes using an alcohol-based fixative (Alcorfix) provide O&P examinations equivalent to or better than those done by processing of PVA-formalin-fixed stool using a SpinCon concentration device. Parasep tubes revealed filtration performance equivalent to that of the SpinCon concentration device using PVA-formalin-fixed stool containing protozoa. Specimens cocollected in Parasep tubes containing PVA-formalin and Alcorfix revealed comparable morphology and staining for various protozoa. Alcorfix effectively fixed live Cryptosporidium and microsporidia such that morphology and staining were conserved for modified acid-fast and modified trichrome stains. A work flow analysis revealed significant time savings for batches of 10 or 30 O&P specimens in tubes with Alcorfix compared to the amount of time that it took to analyze the same number of specimens in tubes with PVA-formalin. The direct hands-on time savings with Mini Parasep tubes were 17 min and 41 s and 32 min and 1 s for batches of 10 and 30 specimens, respectively. Parasep tubes containing Alcorfix provide significant work flow advantages to laboratories that process medium to high volumes of O&P specimens by streamlining processing and converting to a single tube. These improvements in work flow, reduction of the amount of formalin used in the laboratory, and equivalent microscopy results are attractive advancements in O&P testing for North American diagnostic parasitology laboratories.

Antepartum screening for group B Streptococcus by three FDA-cleared molecular tests and effect of shortened enrichment culture on molecular detection rates.

Neonatal Streptococcus agalactiae infections cause significant morbidity and mortality, and antenatal screening is recommended. We compared three U.S. Food and Drug Administration (FDA)-cleared nucleic acid amplification tests (NAATs) to culture using 314 vaginal/rectal swabs after 18 to 24 h (recommended period) and 4 to 8 h (shortened period) of broth enrichment. Agreement of the NAATs with each other was high (97.1% to 98.4%), but culture was less sensitive than all NAATs (67% to 73%). A shortened period of broth culture enrichment resulted in 1 false-negative result in 68 (1.5%). The NAATs performed comparably and were more sensitive than culture.

Detection of non-jejuni and -coli Campylobacter species from stool specimens with an immunochromatographic antigen detection assay.

The STAT! Campy immunochromatographic assay for Campylobacter antigen was compared to culture for 500 clinical stool specimens. Antigen was detected in six culture-negative, PCR-positive specimens. C. upsaliensis, a pathogenic species that is traditionally difficult to recover in routine stool cultures, was detected in two of these culture-negative specimens. This study provides evidence that antigen testing may cross-react with at least one additional non-jejuni and -coli Campylobacter species that may be missed by routine culture for campylobacteriosis.

Association of Campylobacter upsaliensis with persistent bloody diarrhea.

Campylobacter upsaliensis is a zoonotic, emerging pathogen that is not readily recovered in traditional stool culture. This case represents the first report of persistent bloody diarrhea with C. upsaliensis that was confirmed by filtration culture, PCR, and sequencing.

Oseltamivir-resistant influenza A 2009 H1N1 virus in immunocompromised patients.

BACKGROUND: First-line treatment of influenza A 2009 H1N1 relies on neuraminidase inhibitors such as oseltamivir. Resistance conferred by the H275Y neuraminidase gene mutation is concerning and likely to increase. OBJECTIVES: To characterize oseltamivir resistance in a hospital-based patient population. PATIENTS AND METHODS: All available respiratory specimens positive for influenza A by direct fluorescent antibody, RT-PCR, or culture from patients at the University of Utah 5/09-12/09 were collected. Specimens were confirmed as 2009 H1N1 by the Utah Department of Health. RT-PCR and pyrosequencing were used to test for the H275Y mutation (CDC protocol). PyroMark Q24 AQ software (Qiagen, Valencia, CA, USA) was used to allow for quantitative H275Y mutation analysis. Medical records of patients with resistant virus were reviewed. RESULTS: We tested 191 influenza A virus-positive samples from 187 unique patients. Fifty (27%) patients were hospitalized. Four patient specimens (2.1%) were found to carry the H275Y mutation. Three patients were hospitalized, representing 6% of inpatient samples tested. Three patients had undergone hematopoietic stem cell transplant in the past year. Two patients died. Their influenza viruses were confirmed to be oseltamivir-resistant at an independent reference laboratory and through the Center for Disease Control and Prevention (CDC). One patient reported no history of prior oseltamivir exposure. CONCLUSIONS: Widespread oseltamivir resistance among 2009 H1N1 remains a potential threat. Rapid techniques, such as pyrosequencing, which has the additional benefit of identifying mixed mutant populations of virus, may play a key role in identifying at-risk individuals and potentially unsuspected cases. Targeted surveillance of immunocompromised patients will be critical toward improving future influenza planning and therapy.