MSG07: An International Cohort Study Comparing Epidemiology and Outcomes of Patients With Cryptococcus neoformans or Cryptococcus gattii Infections.

BACKGROUND: Cryptococcosis due to Cryptococcus neoformans and Cryptococcus gattii varies with geographic region, populations affected, disease manifestations, and severity of infection, which impact treatment. METHODS: We developed a retrospective cohort of patients diagnosed with culture-proven cryptococcosis during 1995-2013 from 5 centers in North America and Australia. We compared underlying diseases, clinical manifestations, treatment, and outcomes in patients with C. gattii or C. neoformans infection. RESULTS: A total of 709 patients (452 C. neoformans; 257 C. gattii) were identified. Mean age was 50.2 years; 61.4% were male; and 52.3% were white. Time to diagnosis was prolonged in C. gattii patients compared with C. neoformans (mean, 52.2 vs 36.0 days; P < .003), and there was a higher proportion of C. gattii patients without underlying disease (40.5% vs 10.2%; P < .0001). Overall, 59% had central nervous system (CNS) infection, with lung (42.5%) and blood (24.5%) being common sites. Pulmonary infection was more common in patients with C. gattii than in those with C. neoformans (60.7% vs 32.1%; P < .0001). CNS or blood infections were more common in C. neoformans-infected patients (P ≤ .0001 for both). Treatment of CNS disease with induction therapy of amphotericin B and flucytosine occurred in 76.4% of patients. Crude 12-month mortality was higher in patients with C. neoformans (28.4% vs 20.2%; odds ratio, 1.56 [95% confidence interval, 1.08-2.26]). CONCLUSIONS: This study emphasizes differences in species-specific epidemiology and outcomes of patients with cryptococcosis, including underlying diseases, site of infection, and mortality. Species identification in patients with cryptococcosis is necessary to discern epidemiologic patterns, guide treatment regimens, and predict clinical progression and outcomes.

Ecology and Epidemiology of Tickborne Pathogens, Washington, USA, 2011-2016.

Tickborne diseases are rare in Washington, USA, and the ecology of these pathogens is poorly understood. We integrated surveillance data from humans and ticks to better describe their epidemiology and ecology. During 2011-2016, a total of 202 tickborne disease cases were reported in Washington residents. Of these, 68 (34%) were autochthonous, including cases of Lyme disease, Rocky Mountain spotted fever, tickborne relapsing fever, and tularemia. During May 2011-December 2016, we collected 977 host-seeking ticks, including Ixodes pacificus, I. angustus, I. spinipalpis, I. auritulus, Dermacentor andersoni, and D. variabilis ticks. The prevalence of Borrelia burgdorferi sensu stricto in I. pacificus ticks was 4.0%; of B. burgdorferi sensu lato, 3.8%; of B. miyamotoi, 4.4%; and of Anaplasma phagocytophilum, 1.9%. We did not detect Rickettsia rickettsii in either Dermacentor species. Case-patient histories and detection of pathogens in field-collected ticks indicate that several tickborne pathogens are endemic to Washington.

National Outbreak of Multidrug Resistant Salmonella Heidelberg Infections Linked to a Single Poultry Company.

IMPORTANCE: This large outbreak of foodborne salmonellosis demonstrated the complexity of investigating outbreaks linked to poultry products. The outbreak also highlighted the importance of efforts to strengthen food safety policies related to Salmonella in chicken parts and has implications for future changes within the poultry industry. OBJECTIVE: To investigate a large multistate outbreak of multidrug resistant Salmonella Heidelberg infections. DESIGN: Epidemiologic and laboratory investigations of patients infected with the outbreak strains of Salmonella Heidelberg and traceback of possible food exposures. SETTING: United States. Outbreak period was March 1, 2013 through July 11, 2014. PATIENTS: A case was defined as illness in a person infected with a laboratory-confirmed Salmonella Heidelberg with 1 of 7 outbreak pulsed-field gel electrophoresis (PFGE) XbaI patterns with illness onset from March 1, 2013 through July 11, 2014. A total of 634 case-patients were identified through passive surveillance; 200/528 (38%) were hospitalized, none died. RESULTS: Interviews were conducted with 435 case-patients: 371 (85%) reported eating any chicken in the 7 days before becoming ill. Of 273 case-patients interviewed with a focused questionnaire, 201 (74%) reported eating chicken prepared at home. Among case-patients with available brand information, 152 (87%) of 175 patients reported consuming Company A brand chicken. Antimicrobial susceptibility testing was completed on 69 clinical isolates collected from case-patients; 67% were drug resistant, including 24 isolates (35%) that were multidrug resistant. The source of Company A brand chicken consumed by case-patients was traced back to 3 California production establishments from which 6 of 7 outbreak strains were isolated. CONCLUSIONS: Epidemiologic, laboratory, traceback, and environmental investigations conducted by local, state, and federal public health and regulatory officials indicated that consumption of Company A chicken was the cause of this outbreak. The outbreak involved multiple PFGE patterns, a variety of chicken products, and 3 production establishments, suggesting a reservoir for contamination upstream from the production establishments. Sources of bacteria and genes responsible for resistance, such as farms providing birds for slaughter or environmental reservoir on farms that raise chickens, might explain how multiple PFGE patterns were linked to chicken from 3 separate production establishments and many different poultry products.

Two Listeria monocytogenes Pseudo-outbreaks Caused by Contaminated Laboratory Culture Media.

Listeriosis is a serious foodborne infection that disproportionately affects elderly adults, pregnant women, newborns, and immunocompromised individuals. Diagnosis is made by culturing Listeria monocytogenes from sterile body fluids or from products of conception. This report describes the investigations of two listeriosis pseudo-outbreaks caused by contaminated laboratory media made from sheep blood.

Epizootiological investigation of a Q fever outbreak and implications for future control strategies.

OBJECTIVE: To describe the epizootiological investigation of an outbreak of Q fever (Coxiella burnetii infection). DESIGN: Epidemiological study. ANIMALS: 17 goat herds in Washington, Montana, and Oregon. PROCEDURES: In April 2011, an abortion storm at a commercial goat farm in Washington was determined to be caused by C burnetii. A joint epidemiological investigation by public health and veterinary professionals was subsequently performed to assess the extent of the outbreak by performing a trace-forward of goats sold from the index farm, to determine risk factors associated with infection, and to implement control measures. A herd management plan was developed to control the outbreak and reduce risk of human exposure. Quarantine and temporary holds preventing the sale or movement of goats allowed time for trace-forward investigation, education of farmers regarding disease risk, and testing to determine the scope of the outbreak. RESULTS: 17 farms were affected; 21 human Q fever cases were identified. Bacterial shedding in feces, vaginal fluid, or milk was confirmed in 156 of 629 (25%) goats tested by PCR assay. Seroprevalence of antibodies against C burnetii in goats, determined by ELISA, was 12%. The risk for C burnetii infection in goats was highest among females, those on farms associated with human Q fever, and those on Washington farms. A protective effect was observed for goats at farms where the primary form of goat carcass disposal was burial. CONCLUSIONS AND CLINICAL RELEVANCE: This outbreak illustrated the importance of a joint investigation for zoonotic pathogens and the need to expand and strengthen relationships between medical, public health, and veterinary partners. Heightened awareness and enhanced veterinary diagnostic capabilities for C burnetii are needed to identify and control outbreaks expediently.

Epidemiology of Lyme disease in low-incidence states.

Lyme disease is the most common vector-borne disease in the U.S. Surveillance data from four states with a low-incidence of Lyme disease was evaluated. Most cases occurred after travel to high-incidence Lyme disease areas. Cases without travel-related exposure in low-incidence states differed epidemiologically; misdiagnosis may be common in these areas.

The descriptive epidemiology of yersiniosis: a multistate study, 2005-2011.

OBJECTIVES: Yersiniosis, a foodborne infection of zoonotic origin caused by the bacteria Yersinia enterocolitica and Yersinia pseudotuberculosis, is a reportable disease in 38 states. Both sporadic and foodborne outbreaks of yersiniosis have been reported in the U.S., with annual occurrence of an estimated 98,000 episodes of illness, 533 hospitalizations, and 29 deaths. We analyzed surveillance data from nine non-FoodNet-participating U.S. states during the period 2005-2011 to describe the epidemiology of this disease. METHODS: As part of a passive surveillance system, laboratory-confirmed cases of yersiniosis were reported to state health departments in Arizona, Illinois, Michigan, Missouri, Nebraska, North Carolina, South Carolina, Washington, and Wisconsin. We calculated overall, age-, and race-specific annual incidence rates per 100,000 population using 2010 Census data as the denominator. We used Poisson regression to examine seasonal variation and annual incidence trends by race, age group, and overall. RESULTS: The average annual incidence of yersiniosis was 0.16 cases per 100,000 population during 2005-2011. We observed a statistically significant decreasing annual trend of yersiniosis incidence among African Americans <5 years of age (p<0.01), whereas white people aged 19-64 years (p=0.08) and Hispanic people (p=0.05) had an overall increasing annual incidence of yersiniosis. We observed higher incidence during October-December (p<0.01) and January-March (p=0.03) quarters among African Americans, whereas white people had a higher incidence during April-June (p=0.05). CONCLUSION: This multistate analysis revealed differences in the epidemiology of yersiniosis by race/ethnicity that may be useful for future research and prevention efforts. While this study was consistent with the FoodNet report in recognizing the high and declining incidence among African American children and winter seasonality among African Americans, our study also identified April-June seasonality among the white population.

Tickborne relapsing fever - United States, 1990-2011.

Tickborne relapsing fever (TBRF) is a zoonosis caused by spirochetes of the genus Borrelia and transmitted to humans by ticks of the genus Ornithodoros. TBRF is endemic in the western United States, predominately in mountainous regions. Clinical illness is characterized by recurrent bouts of fever, headache, and malaise. Although TBRF is usually a mild illness, severe sequelae and death can occur. This report summarizes the epidemiology of 504 TBRF cases reported from 12 western states during 1990-2011. Cases occurred most commonly among males and among persons aged 10‒14 and 40‒44 years. Most reported infections occurred among nonresident visitors to areas where TBRF is endemic. Clinicians and public health practitioners need to be familiar with current epidemiology and features of TBRF to adequately diagnose and treat patients and recognize that any TBRF case might indicate an ongoing source of potential exposure that needs to be investigated and eliminated.

Valley fever: finding new places for an old disease: Coccidioides immitis found in Washington State soil associated with recent human infection.

We used real-time polymerase chain reaction and culture to demonstrate persistent colonization of soils by Coccidioides immitis, an agent of valley fever, in Washington State linked to recent human infections and located outside the endemic range. Whole-genome sequencing confirmed genetic identity between isolates from soil and one of the case-patients.

Coccidioides immitis identified in soil outside of its known range - Washington, 2013.

Coccidioidomycosis ("valley fever") is caused by inhaling spores of the soil-dwelling fungi Coccidioides immitis or Coccidioides posadasii. Most infections are subclinical. When clinical manifestations do occur (typically 1-4 weeks after exposure), they are similar to those associated with influenza or community-acquired pneumonia. Disseminated disease is rare. Residual pulmonary nodules can lead to chronic lung disease. Fluconazole or other triazoles often are used for treatment, but mild cases often resolve without specific therapy. A total of 17,802 cases were reported in the United States in 2012.

Treatment and outcomes among patients with Cryptococcus gattii infections in the United States Pacific Northwest.

BACKGROUND: Cryptococcus gattii is a fungal pathogen causing an emerging outbreak in the United States Pacific Northwest (PNW). Treatment guidelines for cryptococcosis are primarily based on data from C. neoformans infections; applicability to PNW C. gattii infection is unknown. We evaluated the relationship between initial antifungal treatment and outcomes for PNW C. gattii patients. METHODS: Cases were defined as culture-confirmed invasive C. gattii infections among residents of Oregon and Washington States during 2004-2011. Clinical data were abstracted from medical records through one year of follow-up. Recommended initial treatment for central nervous system (CNS), bloodstream, and severe pulmonary infections is amphotericin B and 5-flucytosine; for non-severe pulmonary infections, recommended initial treatment is fluconazole. Alternative initial treatment was defined as any other initial antifungal treatment. RESULTS: Seventy patients survived to diagnosis; 50 (71%) received the recommended initial treatment and 20 (29%) received an alternative. Fewer patients with pulmonary infections [21 (64%)] than CNS infections [25 (83%)] received the recommended initial treatment (p = 0.07). Among patients with pulmonary infections, those with severe infections received the recommended initial treatment less often than those with non-severe infections (11% vs. 83%, p<0.0001). Eight patients with severe pulmonary infections received alternative initial treatments; three died. Four patients with non-severe pulmonary infections received alternative initial treatments; two died. There was a trend towards increased three-month mortality among patients receiving alternative vs. recommended initial treatment (30% vs. 14%, p = 0.12), driven primarily by increased mortality among patients with pulmonary disease receiving alternative vs. recommended initial treatment (42% vs. 10%, p = 0.07). CONCLUSIONS: C. gattii patients with pulmonary infections--especially severe infections--may be less likely to receive recommended treatment than those with CNS infections; alternative treatment may be associated with increased mortality. Reasons for receipt of alternative treatment among C. gattii patients in this area should be investigated, and clinician awareness of recommended treatment reinforced.

First reported multistate human Q fever outbreak in the United States, 2011.

In April, 2011, the Q fever bacterium Coxiella burnetii was identified at a Washington farm where an abortion storm took place among goats. Soon after, Q fever cases were reported among visitors to the farm from Washington and Montana. A cross-sectional investigation was conducted among humans and goats associated with the index farm or with 16 other farms that purchased goats from the index farm or housed goats at the index farm for breeding purposes. Questionnaire data were analyzed, along with human and goat specimens collected for evidence of C. burnetii infection. Twenty-one persons (19%) of the 109-person cohort from Washington and Montana met the outbreak case definition of an epidemiologic link to the index farm and a C. burnetii Phase II immunoglobulin G (IgG) titer ≥1:128 by immunofluorescence assay. Seventy-one percent of cases (15 of 21) were symptomatic, compared with approximately 50% during previous Q fever outbreaks. National Q fever surveillance reports increase in frequency with age, but 29% (6 of 21) of cases during this outbreak occurred in children aged <14 years. Goat-specific Q fever risk factors included direct contact with a newborn (prevalence ratio [PR] 10.7; confidence interval [CI] 1.5, 77.4), exposure to a newborn that died (PR 5.5; CI 1.7, 18.2), exposure to a weak newborn (PR 4.4; CI 1.7, 11.6), living on a property with goats (PR 4.2; CI 1.3, 13.9), and direct contact with birth/afterbirth products (PR 2.8; CI 1.1, 6.9). Evidence of C. burnetii infection was detected in all 17 goat herds sampled (13 Washington, 3 Montana, 1 Oregon) by PCR and/or enzyme-linked immunosorbent assay. Following this investigation, Washington and Montana implemented a herd management plan to encourage best-management practices among livestock owners, reduce the potential for future outbreaks, and promote continued communication between state public health and agricultural authorities.

Cryptococcus gattii in the United States: genotypic diversity of human and veterinary isolates.

BACKGROUND: Cryptococcusgattii infections are being reported in the United States (US) with increasing frequency. Initially, US reports were primarily associated with an ongoing C. gattii outbreak in the Pacific Northwest (PNW) states of Washington and Oregon, starting in 2004. However, reports of C. gattii infections in patients from other US states have been increasing since 2009. Whether this is due to increasing frequency of disease, greater recognition within the clinical community, or both is currently unknown. METHODOLOGY/PRINCIPAL FINDINGS: During 2005-2013, a total of 273 C. gattii isolates from human and veterinary sources in 16 US states were collected. Of these, 214 (78%) were from the Pacific Northwest (PNW) and comprised primarily the clonal C. gattii genotypes VGIIa (64%), VGIIc (21%) and VGIIb (9%). The 59 isolates from outside the PNW were predominantly molecular types VGIII (44%) and VGI (41%). Genotyping using multilocus sequence typing revealed small clusters, including a cluster of VGI isolates from the southeastern US, and an unrelated cluster of VGI isolates and a large cluster of VGIII isolates from California. Most of the isolates were mating type MATα, including all of the VGII isolates, but one VGI and three VGIII isolates were mating type MATa. CONCLUSIONS/SIGNIFICANCE: We provide the most comprehensive report to date of genotypic diversity of US C. gattii isolates both inside and outside of the PNW. C. gattii may have multiple endemic regions in the US, including a previously-unrecognized endemic region in the southeast. Regional clusters exist both in California and the Southeastern US. VGII strains associated with the PNW outbreak do not appear to have spread substantially beyond the PNW.

Presence and persistence of Coxiella burnetii in the environments of goat farms associated with a Q fever outbreak.

Q fever is a zoonotic disease caused by inhalation of the bacterium Coxiella burnetii. Ruminant livestock are common reservoirs for C. burnetii, and bacteria present in aerosols derived from the waste of infected animals can infect humans. The significance of infection from material deposited in the environment versus transmission directly from infected animals is not known. In 2011, an outbreak of Q fever cases on farms in Washington and Montana was associated with infected goats. A study was undertaken to investigate the quantity and spatial distribution of C. burnetii in the environment of these goat farms. Soil, vacuum, and sponge samples collected on seven farms epidemiologically linked to the outbreak were tested for the presence of C. burnetii DNA by quantitative PCR. Overall, 70.1% of the samples were positive for C. burnetii. All farms had positive samples, but the quantity of C. burnetii varied widely between samples and between farms. High quantities of C. burnetii DNA were in goat housing/birthing areas, and only small quantities were found in samples collected more than 50 m from these areas. Follow-up sampling at one of the farms 1 year after the outbreak found small quantities of C. burnetii DNA in air samples and large quantities of C. burnetii persisting in soil and vacuum samples. The results suggest that the highest concentrations of environmental C. burnetii are found in goat birthing areas and that contamination of other areas is mostly associated with human movement.

Coccidioidomycosis acquired in Washington State.

Clinical, laboratory, and epidemiologic evidence suggest that 3 individuals with acute coccidioidomycosis were exposed in Washington State, significantly beyond previously identified endemic areas. Given the patients' lack of recent travel, coccidioidomycosis was not suspected, leading to delays in diagnosis and appropriate therapy. Clinicians should be aware of this possibility and consider the diagnosis.

Epidemiologic cutoff values for triazole drugs in Cryptococcus gattii: correlation of molecular type and in vitro susceptibility.

Cryptococcus gattii causes infection in tropical and subtropical regions worldwide but has garnered increased attention since its 1999 emergence in North America. C. gattii can be divided into 4 molecular types that may represent cryptic species. Recent evidence has shown that azole antifungal MIC values differ among these molecular types. We tested a large collection of C. gattii isolates for susceptibility to 4 azole drugs. We found that isolates of molecular type VGII have the highest geometric mean (GM) fluconazole MIC values (8.6 µg/mL), while isolates of molecular type VGI have the lowest (1.7 µg/mL). For fluconazole, itraconazole, and voriconazole GM MIC values, VGI < VGIII < VGIV < VGII. The GM MIC values for posaconazole were similarly represented across molecular types, with the exception that VGII < VGIII and VGIV. We used the MIC values to establish preliminary epidemiologic cutoff values for each azole and molecular type of C. gattii.

Whole genome sequence analysis of Cryptococcus gattii from the Pacific Northwest reveals unexpected diversity.

A recent emergence of Cryptococcus gattii in the Pacific Northwest involves strains that fall into three primarily clonal molecular subtypes: VGIIa, VGIIb and VGIIc. Multilocus sequence typing (MLST) and variable number tandem repeat analysis appear to identify little diversity within these molecular subtypes. Given the apparent expansion of these subtypes into new geographic areas and their ability to cause disease in immunocompetent individuals, differentiation of isolates belonging to these subtypes could be very important from a public health perspective. We used whole genome sequence typing (WGST) to perform fine-scale phylogenetic analysis on 20 C. gattii isolates, 18 of which are from the VGII molecular type largely responsible for the Pacific Northwest emergence. Analysis both including and excluding (289,586 SNPs and 56,845 SNPs, respectively) molecular types VGI and VGIII isolates resulted in phylogenetic reconstructions consistent, for the most part, with MLST analysis but with far greater resolution among isolates. The WGST analysis presented here resulted in identification of over 100 SNPs among eight VGIIc isolates as well as unique genotypes for each of the VGIIa, VGIIb and VGIIc isolates. Similar levels of genetic diversity were found within each of the molecular subtype isolates, despite the fact that the VGIIb clade is thought to have emerged much earlier. The analysis presented here is the first multi-genome WGST study to focus on the C. gattii molecular subtypes involved in the Pacific Northwest emergence and describes the tools that will further our understanding of this emerging pathogen.

Age as an independent risk factor for intensive care unit admission or death due to 2009 pandemic influenza A (H1N1) virus infection.

OBJECTIVE: This study evaluated risk factors for intensive care unit (ICU) admission or death among people hospitalized with 2009 pandemic influenza A (pH1N1) virus infection. METHODS: We based analyses on data collected in Washington State from April 27 to September 18, 2009, on deceased or hospitalized people with laboratory-confirmed pH1N1 infection reported by health-care providers and hospitals as part of enhanced public health surveillance. We used bivariate analyses and multivariable logistic regression to identify risk factors associated with ICU admission or death due to pH1N1. RESULTS: We identified 123 patients admitted to the hospital but not an ICU and 61 patients who were admitted to an ICU or died. Independent of high-risk medical conditions, both older age and delayed time to hospital admission were identified as risk factors for ICU admission or death due to pH1N1. Specifically, the odds of ICU admission or death were 4.44 times greater among adults aged 18-49 years (95% confidence interval [CI] 1.97, 10.02) and 5.93 times greater among adults aged 50-64 years (95% CI 2.24, 15.65) compared with pediatric patients < 18 years of age. Likewise, hospitalized cases admitted more than two days after illness onset had 2.17 times higher odds of ICU admission or death than those admitted within two days of illness onset (95% CI 1.10, 4.25). CONCLUSION: Although certain medical conditions clearly influence the need for hospitalization among people infected with pH1N1 virus, older age and delayed time to admission each played an independent role in the progression to ICU admission or death among hospitalized patients.

Epidemiology competency development and application to training for local and regional public health practitioners.

In 2002, the Northwest Center for Public Health Practice (NWCPHP) at the University of Washington initiated the Epidemiology Competencies Project, with the goal of developing competency-based epidemiology training for non-epidemiologist public health practitioners in the northwestern United States. An advisory committee consisting of epidemiology faculty and experienced public health practitioners developed the epidemiology competencies. NWCPHP used the competencies to guide the development of in-person trainings, a series of online epidemiology modules, and a Web-based repository of epidemiology teaching materials. The epidemiology competencies provided a framework for collaborative work between NWCPHP and local and regional public health partners to develop trainings that best met the needs of a particular public health organization. Evaluation surveys indicated a high level of satisfaction with the online epidemiology modules developed from the epidemiology competencies. However, measuring the effectiveness of competency-based epidemiology training for expanding epidemiology knowledge and skills of the public health workforce remains a challenge.

Pandemic policy and planning considerations for universities: findings from a tabletop exercise.

The potential for a novel influenza virus to cause a pandemic represents a significant threat to global health. Planning for pandemic flu, as compared to planning for other types of hazards, presents some unique challenges to businesses, communities, and education institutions. To identify and address the challenges that may be faced by major metropolitan universities during a flu pandemic, a tabletop exercise was developed, offered, and evaluated. Its purpose was to assess existing University of Washington (UW) plans and policies for responding to an influenza pandemic. On May 31, 2006, more than 50 participants, including UW administrators and unit leaders and a number of key external partners, participated in a tabletop exercise designed to simulate all phases of an influenza pandemic. This exercise revealed existing gaps in university pandemic influenza plans and policies, including issues related to isolation and quarantine, continuity of operations, disaster mental health services, integration of volunteers into a disaster response, tracking travel of university students and personnel, communication problems, and ways to meet the needs of resident and foreign students and faculty during an outbreak. Policy and planning recommendations are offered that address each of these challenges faced by UW as well as other major research universities and colleges.