Coccidioides is the fungal causative agent of Valley fever, a primarily pulmonary disease caused by inhalation of fungal arthroconidia, or spores. Although Coccidioides has been an established pathogen for 120 years and is responsible for hundreds of thousands of infections per year, little is known about when and where infectious Coccidioides arthroconidia are present within the ambient air in endemic regions. Long-term air sampling programs provide a means to investigate these characteristics across space and time. Here we present data from > 18 months of collections from 11 air sampling sites across the Phoenix, Arizona, metropolitan area. Overall, prevalence was highly variable across space and time with no obvious spatial or temporal correlations. Several high prevalence periods were identified at select sites, with no obvious spatial or temporal associations. Comparing these data with weather and environmental factor data, wind gusts and temperature were positively associated with Coccidioides detection, while soil moisture was negatively associated with Coccidioides detection. These results provide critical insights into the frequency and distribution of airborne arthroconidia and the associated risk of inhalation and potential disease that is present across space and time in a highly endemic locale.

Background Coronavirus disease 2019 (COVID-19), the respiratory disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was first identified in Wuhan, China and has since become pandemic. As part of initial response activities in the United States, enhanced contact investigations were conducted to enable early identification and isolation of additional cases and to learn more about risk factors for transmission.Methods Close contacts of nine early travel-related cases in the United States were identified. Close contacts meeting criteria for active monitoring were followed, and selected individuals were targeted for collection of additional exposure details and respiratory samples. Respiratory samples were tested for SARS-CoV-2 by real-time reverse transcription polymerase chain reaction (RT-PCR) at the Centers for Disease Control and Prevention.Results There were 404 close contacts who underwent active monitoring in the response jurisdictions; 338 had at least basic exposure data, of whom 159 had ≥1 set of respiratory samples collected and tested. Across all known close contacts under monitoring, two additional cases were identified; both secondary cases were in spouses of travel-associated case patients. The secondary attack rate among household members, all of whom had ≥1 respiratory sample tested, was 13% (95% CI: 4 – 38%).Conclusions The enhanced contact tracing investigations undertaken around nine early travel-related cases of COVID-19 in the United States identified two cases of secondary transmission, both spouses. Rapid detection and isolation of the travel-associated case patients, enabled by public awareness of COVID-19 among travelers from China, may have mitigated transmission risk among close contacts of these cases.Competing Interest StatementThe authors have declared no competing interest.Funding StatementNo external funding was sought or received.Author DeclarationsAll relevant ethical guidelines have been followed; any necessary IRB and/or ethics committee approvals have been obtained and details of the IRB/oversight body are included in the manuscript.YesAll necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived.YesI understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).YesI have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.YesData may be available upon reasonable request.

We describe an incidental Burkholderia pseudomallei laboratory exposure in Arizona, USA. Because melioidosis cases are increasing in the United States and B. pseudomallei reservoirs have been discovered in the Gulf Coast Region, US laboratory staff could be at increased risk for B. pseudomallei exposure.

On November 7, 2022, dengue virus (DENV), which is not endemic in the continental United States (1), was identified in a Maricopa County, Arizona resident by reverse transcription–polymerase chain reaction (RT-PCR) testing at Arizona State Public Health Laboratory (ASPHL). The patient (patient A) was admitted to a hospital on October 19 for a dengue-like illness, 7 days after traveling to and remaining in Mexicali, Mexico for <4 hours. Patient A was hospitalized for 3 days and subsequently recovered. Maricopa County Environmental Services Department (MCESD) conducted retrospective testing for DENV in samples collected from 21 mosquito pools located within 5 miles (8 km) of patient A’s residence during October 1–November 3. A sample collected from one mosquito pool (pool A) on October 5 was positive for DENV. Whole genome sequencing by CDC’s Dengue Branch later revealed that closely related DENV-3 strains not known to be circulating in the patient’s travel region were identified in both patient A and pool A, suggesting local DENV transmission.

BACKGROUND: Short-term rehabilitation units present unique infection control challenges due to high turnover and medically complex residents. In June 2021, Maricopa County Department of Public Health (MCDPH) was notified of a SARS-CoV-2 Delta outbreak in a skilled nursing facility short-term rehabilitation unit. We describe the outbreak and assess vaccine effectiveness (VE). METHODS: Facility electronic medical records were reviewed for residents who spent >1 night on the affected unit between June 10-July 23, 2021, to collect demographics, SARS-CoV-2 test results, underlying medical conditions, vaccination status, and clinical outcomes. COVID-19 VE estimates using Cox proportional hazards models were calculated. RESULTS: Forty (37%) of 109 short-stay rehabilitation unit residents who met inclusion criteria tested positive for SARS-CoV-2. SARS-CoV-2 positive case-patients were mostly male (58%) and white (78%) with a median age of 65 (range: 27-92) years; 11 (27%) were immunocompromised. Of residents, 39% (10 cases; 32 non-cases) received 2-doses and 9% (4 cases, 6 non-cases) received 1-dose of mRNA vaccine. Among non-immunocompromised residents, adjusted 2-dose primary-series mRNA VE against symptomatic infection was 80% (95% CI: 15, 95). More cases were hospitalized (33%) or died (38%) than non-cases (10% hospitalized; 16% died). CONCLUSIONS: In this large SARS-CoV-2 Delta outbreak in a high-turnover short term rehabilitation unit, a low vaccination rate and medically complex resident population were noted alongside severe outcomes. VE of 2-dose primary-series mRNA vaccine against symptomatic infection was the highest in non-immunocompromised residents. Health departments can use vaccine coverage data to prioritize facilities for assistance in preventing outbreaks.

The Maricopa County Department of Public Health in Arizona investigated three COVID-19 outbreaks associated with club sports, two in tournaments and one in a hockey league. During September through November 2020, 195 team-associated and 69 secondary household contact cases were identified among 2093 athletes, coaches, and staff members; the team attack rate ranged from 6% to 72%. Outbreaks occurred during high community transmission periods in Maricopa County. Identification of contacts and characterization of prevention strategies were challenging because of limited cooperation from athletes, families, and staff. (Am J Public Health. 2022;112(2):216-219. https://doi.org/10.2105/AJPH.2021.306579).

We conducted a community seroprevalence survey in Arizona, from September 12 to October 1, 2020, to determine the presence of antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We used the seroprevalence estimate to predict SARS-CoV-2 infections in the jurisdiction by applying the adjusted seroprevalence to the county's population. The estimated community seroprevalence of SARS-CoV-2 infections was 4.3 times greater (95% confidence interval=2.2, 7.5) than the number of reported cases. Field surveys with representative sampling provide data that may help fill in gaps in traditional public health reporting. (Am J Public Health. 2022;112(1):38-42. https://doi.org/10.2105/AJPH.2021.306568).

OBJECTIVE: To describe clinical, diagnostic, and epidemiological features of an outbreak of leptospirosis in dogs in Maricopa County, Ariz, from January 2016 through June 2017. ANIMALS: 71 case and 281 control dogs. PROCEDURES: Cases were classified as confirmed, probable, suspect, or not a case on the basis of medical record data that fulfilled clinical, diagnostic, and epidemiological criteria. Potential exposures were assessed by owner survey. For the case-control investigation, control dogs were recruited through owner completion of a July 2017 survey. Summary statistics and ORs for case dog lifestyle factors were reported. RESULTS: 54 dogs were classified as confirmed and 17 as probable cases. For 4 dogs of a household cluster (5 confirmed and 3 probable), the highest microscopic agglutination titer was for serovar Djasiman (Leptospira kirschneri detected by PCR assay), and for 13 dogs of a community outbreak (49 confirmed and 14 probable cases), the highest titer was for serovar Canicola (Leptospira interrogans detected by PCR assay). The 44 case dogs included in the case-control investigation were 7.7 (95% CI, 3.5 to 16.7) and 2.9 times (95% CI, 1.3 to 6.6) as likely as control dogs to have visited dog daycare or to have been kenneled overnight at a boarding facility, respectively, 30 days prior to the onset of clinical signs or diagnosis. CONCLUSIONS AND CLINICAL RELEVANCE: Diagnostic and epidemiological findings indicated 2 outbreaks. Transmission where dogs congregated likely propagated the community outbreak. Outbreaks of leptospiral infections can occur in regions of low prevalence, and a dog's exposure to areas where dogs congregate should be considered when making Leptospira vaccination recommendations.

West Nile virus (WNV), a mosquitoborne flavivirus,* was first identified in the United States in 1999 and first reported in Arizona in 2003 (with 12 human cases); 391 human cases were reported in 2004. Since that time, a median of 103 cases (range = 21–391) have been reported in Arizona annually.† During week 28 in 2019, the Arizona Department of Health Services (ADHS) recorded the highest weekly WNV case count (23) ever reported in Arizona (an incidence of 0.32 cases per 100,000 population) (Figure). This prompted ADHS to investigate the outbreak’s severity to inform prevention, resource allocation, and public messaging.

Coronavirus disease 2019 (COVID-19), the respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was first identified in Wuhan, China and has since become pandemic. In response to the first cases identified in the United States, close contacts of confirmed COVID-19 cases were investigated to enable early identification and isolation of additional cases and to learn more about risk factors for transmission. Close contacts of nine early travel-related cases in the United States were identified and monitored daily for development of symptoms (active monitoring). Selected close contacts (including those with exposures categorized as higher risk) were targeted for collection of additional exposure information and respiratory samples. Respiratory samples were tested for SARS-CoV-2 by real-time reverse transcription polymerase chain reaction at the Centers for Disease Control and Prevention. Four hundred four close contacts were actively monitored in the jurisdictions that managed the travel-related cases. Three hundred thirty-eight of the 404 close contacts provided at least basic exposure information, of whom 159 close contacts had ≥1 set of respiratory samples collected and tested. Across all actively monitored close contacts, two additional symptomatic COVID-19 cases (i.e., secondary cases) were identified; both secondary cases were in spouses of travel-associated case patients. When considering only household members, all of whom had ≥1 respiratory sample tested for SARS-CoV-2, the secondary attack rate (i.e., the number of secondary cases as a proportion of total close contacts) was 13% (95% CI: 4-38%). The results from these contact tracing investigations suggest that household members, especially significant others, of COVID-19 cases are at highest risk of becoming infected. The importance of personal protective equipment for healthcare workers is also underlined. Isolation of persons with COVID-19, in combination with quarantine of exposed close contacts and practice of everyday preventive behaviors, is important to mitigate spread of COVID-19.

OBJECTIVES: Maricopa County, Arizona (2017 population about 4.3 million), is located in the Sonoran Desert. In 2005, the Maricopa County Department of Public Health (MCDPH) established a heat-associated mortality surveillance system that captures data on circumstances of death for Maricopa County residents and visitors. We analyzed 2006-2016 surveillance system data to understand the characteristics and circumstances of heat-associated deaths. METHODS: We classified heat-associated deaths based on International Classification of Diseases, Tenth Revision codes (X30, T67.X, and P81.0) and phrases (heat exposure, environ, exhaustion, sun, heat stress, heat stroke, or hyperthermia) in part I or part II of the death certificate. We summarized data on decedents' demographic characteristics, years lived in Arizona, location of death (indoors vs outdoors), presence and functionality of air conditioning, and whether the decedent had been homeless. We examined significant associations between variables by using the Pearson χ(2) tests and logistic regression. RESULTS: During 2006-2016, MCDPH recorded data on 920 heat-associated deaths, 912 of which included location of injury. Of 565 (62%) heat-associated deaths that occurred outdoors, 458 (81%) were among male decedents and 243 (43%) were among decedents aged 20-49. Of 347 (38%) heat-associated deaths that occurred indoors, 201 (58%) were among decedents aged ≥65. Non-Arizona residents were 5 times as likely as Arizona residents to have a heat-associated death outdoors (P < .001). Of 727 decedents with data on duration of Arizona residency, 438 (60%) had resided in Arizona ≥20 years. CONCLUSIONS: Ongoing evaluation of interventions that target populations at risk for both outdoor and indoor heat-associated deaths can further inform refinement of the surveillance system and identify best practices to prevent heat-associated deaths.

Data on the detailed clinical progression of COVID-19 in conjunction with epidemiological and virological characteristics are limited. In this case series, we describe the first 12 US patients confirmed to have COVID-19 from 20 January to 5 February 2020, including 4 patients described previously(1-3). Respiratory, stool, serum and urine specimens were submitted for SARS-CoV-2 real-time reverse-transcription polymerase chain reaction (rRT-PCR) testing, viral culture and whole genome sequencing. Median age was 53 years (range: 21-68); 8 patients were male. Common symptoms at illness onset were cough (n = 8) and fever (n = 7). Patients had mild to moderately severe illness; seven were hospitalized and demonstrated clinical or laboratory signs of worsening during the second week of illness. No patients required mechanical ventilation and all recovered. All had SARS-CoV-2 RNA detected in respiratory specimens, typically for 2-3 weeks after illness onset. Lowest real-time PCR with reverse transcription cycle threshold values in the upper respiratory tract were often detected in the first week and SARS-CoV-2 was cultured from early respiratory specimens. These data provide insight into the natural history of SARS-CoV-2. Although infectiousness is unclear, highest viral RNA levels were identified in the first week of illness. Clinicians should anticipate that some patients may worsen in the second week of illness.

West Nile virus (WNV) and St. Louis encephalitis virus (SLEV) are closely related mosquito-borne flaviviruses that cause clinical disease ranging from febrile illness to encephalitis. The standard for serological diagnosis is immunoglobulin M (IgM) testing followed by confirmatory plaque reduction neutralization test (PRNT) to differentiate the infecting virus. However, the PRNT is time-consuming and requires manipulation of live virus. During concurrent WNV and SLEV outbreaks in Arizona in 2015, we assessed use of a diagnostic algorithm to simplify testing. It incorporated WNV and SLEV ratios based on positive-to-negative (P/N) values derived from the IgM antibody-capture enzyme-linked immunosorbent assay. We compared each sample's ratio-based result with the confirmed WNV or SLEV sample result indicated by PRNT or PCR testing. We analyzed data from 70 patients with 77 serum and cerebrospinal fluid samples, including 53 patients with confirmed WNV infection and 17 patients with confirmed SLEV infection. Both WNV and SLEV ratios had specificity >/=95%, indicating a high likelihood that each ratio was correctly identifying the infecting virus. The SLEV ratio sensitivity of 30% was much lower than the WNV ratio sensitivity of 91%, likely because of higher cross-reactivity of SLEV antibodies and generation of lower P/N values. The standard for serological diagnosis of WNV and SLEV infections remains IgM testing followed by PRNT. However, these results suggest the ratios could potentially be used as part of a diagnostic algorithm in outbreaks to substantially reduce the need for PRNTs.

West Nile virus (WNV) and St. Louis encephalitis virus (SLEV) are closely related mosquito-borne flaviviruses that can cause neuroinvasive disease. No concurrent WNV and SLEV disease outbreaks have previously been identified. When concurrent outbreaks occurred in 2015 in Maricopa County, Arizona, we collected data to describe the epidemiology, and to compare features of patients with WNV and SLEV neuroinvasive disease. We performed enhanced case finding, and gathered information from medical records and patient interviews. A case was defined as a clinically compatible illness and laboratory evidence of WNV, SLEV, or unspecified flavivirus infection in a person residing in Maricopa County in 2015. We compared demographic and clinical features of WNV and SLEV neuroinvasive cases; for this analysis, a case was defined as physician-documented encephalitis or meningitis and a white blood cell count >5 cells/mm(3) in cerebrospinal fluid. In total, we identified 82 cases, including 39 WNV, 21 SLEV, and 22 unspecified flavivirus cases. The comparative analysis included 21 WNV and 14 SLEV neuroinvasive cases. Among neuroinvasive cases, the median age of patients with SLEV (63 years) was higher than WNV (52 years). Patients had similar symptoms; rash was identified more frequently in WNV (33%) neuroinvasive cases than in SLEV (7%) cases, but this difference was not statistically significant (p = 0.11). In summary, during the first known concurrent WNV and SLEV disease outbreaks, no specific clinical features were identified that could differentiate between WNV and SLEV neuroinvasive cases. Health care providers should consider both infections in patients with aseptic meningitis or encephalitis.

BACKGROUND: Coronavirus disease 2019 (COVID-19) causes a range of illness severity. Mild illness has been reported, but whether illness severity correlates with infectivity is unknown. We describe the public health investigation of a mildly ill, non-hospitalized COVID-19 case who traveled to China. METHODS: The case was a Maricopa County resident with multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-positive specimens collected on January 22, 2020. Contacts were persons exposed to the case on or after the day before case diagnostic specimen collection. Contacts were monitored for 14 days after last known exposure. High-risk contacts had close, prolonged case contact (>/=10 minutes within 2 meters). Medium-risk contacts wore all U.S. Centers for Disease Control and Prevention (CDC)-recommended personal protective equipment during interactions. Nasopharyngeal and oropharyngeal (NP/OP) specimens were collected from the case and high-risk contacts and tested for SARS-CoV-2. RESULTS: Paired case NP/OP specimens were collected for SARS-CoV-2 testing at 11 time points. In 8 pairs (73%), >/=1 specimen tested positive or indeterminate, and in 3 pairs (27%) both tested negative. Specimens collected 18 days after diagnosis tested positive. Sixteen contacts were identified; 11 (69%) had high-risk exposure, including 1 intimate contact, and 5 (31%) had medium-risk exposure. In total, 35 high-risk contact NP/OP specimens were collected for SARS-CoV-2 testing; all 35 pairs (100%) tested negative. CONCLUSIONS: This report demonstrates that SARS-CoV-2 infection can cause mild illness and result in positive tests for up to 18 days after diagnosis, without evidence of transmission to close contacts. These data might inform public health strategies to manage individuals with asymptomatic infection or mild illness.

On August 2, 2018, Maricopa County (Arizona) Department of Public Health (MCDPH) identified two isolates of carbapenemase-producing Klebsiella pneumoniae (KPC-KP), a type of carbapenemase-producing carbapenem-resistant Enterobacteriaceae (CP-CRE), from urine specimens collected on July 17 and July 23 from two residents of a ventilator-capable unit in a skilled nursing facility. CP-CRE are multidrug-resistant organisms typically isolated from persons with a health care exposure (1,2). Invasive CP-CRE infections are associated with a 50% case-fatality rate (3); however, only 31%–63% of asymptomatic carriers are identified with clinical cultures (4,5) and might serve as sources of CP-CRE transmission. Both residents at this skilled nursing facility had indwelling urinary catheters and urinary tract infections, resided in neighboring rooms, and were dependent on nursing care for their activities of daily living; one resident was mechanically ventilated. The Antibiotic Resistance Laboratory Network Mountain Region laboratory in Austin, Texas, performed pulsed-field gel electrophoresis (PFGE) on the two clinical isolates, which were found to have indistinguishable PFGE patterns, suggesting health care–associated transmission. MCDPH and the Arizona Department of Health Services (ADHS) investigated the cluster to prevent additional cases.

Coccidioidomycosis is a debilitating fungal disease caused by inhalation of arthroconidia. We developed a novel approach for detection of airborne Coccidioides and used it to investigate the distribution of arthroconidia across the Phoenix, Arizona, metropolitan area. Air filters were collected daily from 21 stationary air-sampling units across the area: the first set collected before, during and after a large dust storm on August 25, 2015, and the second over the 45-day period September 25-November 8, 2016. Analysis of DNA extracted from the filters demonstrated that the day of the dust storm was not associated with increase of Coccidioides in air samples, although evidence of the low-level polymerase chain reaction (PCR) inhibition was observed in DNA extracted from samples collected on the day of the dust storm. Testing over 45 days identified uneven geographic distribution suggesting Coccidioides hot spots. In 2016, highest daily concentration of arthroconidia was observed between September 25-October 20, and only sporadic low levels were detected after that. These results provide evidence of seasonality and uneven spatial distribution of Coccidioides in the air. Our results demonstrate that routine air monitoring for arthroconidia is possible and provides an important tool for Coccidioides surveillance, which can address important questions about environmental exposure and human infection.

The incidence of reported coccidioidomycosis in the past two decades has increased greatly; monitoring its changing epidemiology is essential for understanding its burden on patients and the healthcare system and for identifying opportunities for prevention and education. We provide an update on recent coccidioidomycosis trends and public health efforts nationally and in Arizona, California, and Washington State. In Arizona, enhanced surveillance shows that coccidioidomycosis continues to be associated with substantial morbidity. California reported its highest yearly number of cases ever in 2016 and has implemented interventions to reduce coccidioidomycosis in the prison population by excluding certain inmates from residing in prisons in high-risk areas. Coccidioidomycosis is emerging in Washington State, where phylogenetic analyses confirm the existence of a unique Coccidioides clade. Additional studies of the molecular epidemiology of Coccidioides will improve understanding its expanding endemic range. Ongoing public health collaborations and future research priorities are focused on characterizing geographic risk, particularly in the context of environmental change; identifying further risk reduction strategies for high-risk groups; and improving reporting of cases to public health agencies.

School nurses often play large roles in implementation of school vaccination requirements aimed at controlling the spread of communicable disease. We analyzed the association between the presence of a school nurse and school-level vaccination rates in Arizona. Using school-level data from Arizona sixth-grade schools ( n = 749), we regressed average sixth-grade school-level immunization rates on presence of a school nurse (registered nurse [RN] or licensed practical nurse [LPN]) and school-level socioeconomic status (SES), controlling for other school- and district-level characteristics. Schools with a nurse had higher overall vaccination rates than those without a nurse (96.1% vs. 95.0%, p < .01). For schools in the lowest SES quartile, the presence of a school nurse was associated with approximately 2 percentage point higher immunization rates. These findings add to the growing literature that defines the impact of school nurses on student health status and outcomes, emphasizing the value of school nurses, especially in lower SES schools.

Leptospirosis is a bacterial zoonosis that affects many mammals, including humans and dogs; dogs can transmit the bacteria to humans, but the frequency of transmission and highest risk exposures are poorly understood. During 2016-2017, the Maricopa County Department of Public Health, Arizona Department of Health Services and Centers for Disease Control and Prevention investigated the zoonotic potential of a canine leptospirosis outbreak in the Phoenix metro area. We identified symptomatic persons exposed to canine leptospirosis cases by conducting active and passive surveillance. We tested dog owners (n = 9) and animal care providers (n = 109) for serological evidence of Leptospira spp. infection (via the microscopic agglutination test [MAT]) and interviewed these persons about their specific exposures to canine cases and general exposures to canine blood and urine. Through surveillance, seven symptomatic persons were identified; six were tested and all were negative by MAT, and of these six, four persons were negative by PCR (two did not have PCR testing). All serosurvey participants (n = 118) were also seronegative. Among animal care providers, bare skin contact with urine/blood from a canine case was reported by 23.2%; two persons reported dog urine splashing in their face. Veterinary technicians were more likely to have bare skin contact with blood from a canine case compared to veterinarians and boarding facility staff (p < 0.001). Infection control practices were inconsistent; when working with specimens from a canine leptospirosis case, 44.6% of participants reported always wearing gloves when working with urine (i.e., collecting specimens), and 54.5% always wore gloves when working with blood. Veterinary technicians were also most likely to engage in all activities involving potential urine/blood contact, such as conducting laboratory tests (p < 0.01). We therefore recommend that veterinary technicians specifically receive targeted education about infection control practices. Our results suggest that dog-to-human transmission of leptospirosis is uncommon.

Rabies postexposure prophylaxis (PEP) is administered for rabies prevention after a human exposure to a potentially rabid animal, such as a bite. Previous studies have reported that rabies PEP is often inappropriately administered. Health professional education was proposed as one potential solution to address inappropriate PEP use. We assessed baseline knowledge, knowledge gain, and knowledge retention among health professionals in Arizona of rabies epidemiology and appropriate PEP administration. Maricopa County Department of Public Health created an online rabies PEP continuing education module and measured knowledge before and after module completion using a 10-question test. The same test was administered three times (pretest, posttest, and retention test at >/=3 months). To assess knowledge gain and retention, we compared median scores using nonparametric methods. A total of 302 respondents completed the pretest (median score, 60%) and posttest (median score, 90%; p < .001); 98 respondents completed all three tests with median scores 60% (pretest), 90% (posttest, p < .01), and 80% (retention test and compared with pretest, p < .01). Sixty-nine (70%) respondents improved their pretest to retention test score by a mean of 2.4 points out of a total 10 points (median: 2 points; range: -5 to 7 points). Only 48% of pretest respondents correctly answered that PEP should not be administered immediately to anyone bitten by a healthy dog. However, 81% and 70% answered correctly on the posttest (p < .0001) and retention test (p = .002), respectively. Respondents demonstrated rabies epidemiology and PEP knowledge gain and >/=3-month knowledge retention after completing the online continuing education module.

We describe a 2016 community-wide recreational water-associated cryptosporidiosis outbreak investigation and response in Maricopa County, Arizona. Persons with a laboratory-confirmed illness were interviewed using a standardized questionnaire that assessed exposures 2 weeks before symptom onset. A convenience sample of managers and operators of chlorine-treated public aquatic facilities was surveyed regarding permanent supplemental treatment systems for Cryptosporidium. Among 437 cases identified (median age 12, range <1-75 years), 260 persons were interviewed. Public-treated recreational water was the most frequently reported exposure (177, 68%) of interviewed persons; almost 1 in 5 (43, 17%) swam when diarrhea was ongoing. After the 2016 outbreak, managers of some facilities expressed intentions to install supplementary water treatment systems, and by May 2017, at least one large facility installed an ultraviolet light system. Strategies to prevent additional illness included community messaging, education, and targeted remediation of affected facilities on the basis of interviews. Challenges to remediation during a cryptosporidiosis outbreak in a large jurisdiction with primarily outdoor pools underscore the importance of promoting healthy swimming practices that help prevent contamination from occurring.

Beginning in October 2017, the Arizona Department of Health Services (ADHS) noted an increase in the number of reported cases of coccidioidomycosis (Figure). According to provisional data (not finalized), the incidence in December 2017 (17.2 per 100,000 population) represented the highest monthly rate in the last 5 years, surpassing the previous peak of 14.2 cases per 100,000 population in September 2015. In total, 4,827 cases of coccidioidomycosis were reported to ADHS during October 2017–March 2018. Whereas case counts typically increase during these months, this particular period represented a 58.3% increase over the 3,050 cases reported during the same months the previous year and a 50.3% increase over the 6-month average of 3,211 cases reported during October–March for the years 2013–2017.

Coccidioidomycosis, a fungal infection endemic to the Southwestern United States, is challenging to diagnose. The coccidioidomycosis enzyme immunoassay (EIA) test is the least expensive and simplest to perform to detect coccidioidomycosis antibodies in the serum. Concerns regarding falsely positive immunoglobulin (Ig) M EIA test results have led to questions about the agreement of commercially available EIA test kits among laboratories. We sought to evaluate the laboratory agreement of the EIA test at three laboratories using both IMMY and Meridian EIA test kits. Sensitivity and specificity of EIA IgM and IgG were calculated as secondary outcomes. The percent agreement of the EIA IgM and IgG test results among all three laboratories was 90% and 89% for IMMY test kits, respectively, and 67% and 80.5% for Meridian test kits, respectively. Agreement between IgM and IgG combined test results was 85.5% and 70.5%, for IMMY and Meridian, respectively. Combined IgM and IgG assays demonstrated a sensitivity of 68% (62.7%-76%) and a specificity of 99.3% (98%-100%) [IMMY] and a sensitivity of 72.4% (57.3%-87.3%) and a specificity of 91.3% (74%-100%) [Meridian]. In summary, results from the IMMY EIA test kit agreed more often across laboratories than Meridian EIA results, especially for the IgM assay. Isolated positive IgM EIA results using the Meridian test kit should be interpreted with caution and consideration of clinical information and test methodology. Further study of the sensitivity and specificity of coccidioidomycosis EIA test kits is warranted.

On 10 August 2016, the Maricopa County Department of Public Health identified culture-confirmed Salmonella enterica serotype Javiana isolates from two persons who reported eating at a seafood restaurant; seven additional cases were reported by 15 August. We investigated to identify a source and prevent further illness. We interviewed persons with laboratory-reported Salmonella Javiana infection. Pulsed-field gel electrophoresis (PFGE) and whole genome sequencing of isolates were performed. A case was defined as diarrheal illness in a person during July to September 2016; confirmed cases had Salmonella Javiana isolate yielding outbreak-related PFGE patterns; probable cases had diarrheal illness and an epidemiologic link to a confirmed case. Case finding was performed (passive surveillance and identification of ill meal companions). A case-control study assessed risk factors for Salmonella Javiana infection among restaurant diners; control subjects were chosen among meal companions. No restaurant workers reported illness. Foods were reportedly cooked according to the Food Code. Food and environmental samples were collected and cultured; Salmonella Javiana with an indistinguishable PFGE pattern was isolated from portioned repackaged raw shrimp, halibut, and a freezer door handle. We identified 50 Salmonella Javiana cases (40 confirmed and 10 probable); illness onset range was from 22 July to 17 September 2016. Isolates from 40 patients had highly related PFGE patterns. Thirty-three (73%) of 45 patients interviewed reported eating at the restaurant. Among 21 case patients and 31 control subjects, unfried cooked shrimp was associated with illness (odds ratio, 6.7; 95% confidence interval, 1.8 to 24.9; P = 0.004). Among restaurant diners, laboratory and case-control evidence indicated shrimp as the possible outbreak source; poor thermal inactivation of Salmonella on shrimp is theorized as a possible cause. Cross-contamination might have prolonged this outbreak; however, the source was not identified and highlights limitations that can arise during these types of investigations.

The Arizona Department of Health Services identified unusually high levels of influenza activity and severe complications during the 2015-2016 influenza season leading to concerns about potential increased disease severity compared with prior seasons. We estimated state-level burden and severity to compare across three seasons using multiple data sources for community-level illness, hospitalisation and death. Severity ratios were calculated as the number of hospitalisations or deaths per community case. Community influenza-like illness rates, hospitalisation rates and mortality rates in 2015-2016 were higher than the previous two seasons. However, ratios of severe disease to community illness were similar. Arizona experienced overall increased disease burden in 2015-2016, but not increased severity compared with prior seasons. Timely estimates of state-specific burden and severity are potentially feasible and may provide important information during seemingly unusual influenza seasons or pandemic situations.

BACKGROUND: St. Louis encephalitis virus is a mosquito-borne flavivirus that infrequently causes epidemic central nervous system infections. In the United States, blood donors are not screened for St. Louis encephalitis virus infection, and transmission through blood transfusion has not been reported. During September 2015, St. Louis encephalitis virus infection was confirmed in an Arizona kidney transplant recipient. An investigation was initiated to determine the infection source. STUDY DESIGN AND METHODS: The patient was interviewed, and medical records were reviewed. To determine the likelihood of mosquito-borne infection, mosquito surveillance data collected at patient and blood donor residences in timeframes consistent with their possible exposure periods were reviewed. To investigate other routes of exposure, organ and blood donor and recipient specimens were obtained and tested for evidence of St. Louis encephalitis virus infection. RESULTS: The patient presented with symptoms of central nervous system infection. Recent St. Louis encephalitis virus infection was serologically confirmed. The organ donor and three other organ recipients showed no laboratory or clinical evidence of St. Louis encephalitis virus infection. Among four donors of blood products received by the patient via transfusion, one donor had a serologically confirmed, recent St. Louis encephalitis virus infection. Exposure to an infected mosquito was unlikely based on the patient's minimal outdoor exposure. In addition, no St. Louis encephalitis virus-infected mosquito pools were identified around the patient's residence. CONCLUSION: This investigation provides evidence of the first reported possible case of St. Louis encephalitis virus transmission through blood product transfusion. Health care providers and public health professionals should maintain heightened awareness for St. Louis encephalitis virus transmission through blood transfusion in settings where outbreaks are identified.

In 2016, CDC saw an increase in cases of acute flaccid myelitis (AFM); 144 persons in 37 states and the District of Columbia were confirmed to have AFM. After investigations in California (1) and Colorado (2) in 2014, CDC characterized AFM as an acute flaccid paralysis (AFP) distinguishable by magnetic resonance imaging (MRI) abnormalities of the gray matter of the anterior and posterior spinal cord segments, involving one or more spinal segments (3). Although certain viruses (e.g., nonpoliovirus enteroviruses, adenoviruses, and West Nile virus) can cause rare cases of AFP, and findings from the 2014 outbreak investigations indicated that enterovirus D68 (EV-D68) was temporally associated with AFM, no viral etiology for AFM has been definitively established (3). In September 2016, an acute care hospital in Arizona notified the Maricopa County Department of Public Health (MCDPH) of a suspected case of AFM and subsequent cluster of 11 children who were evaluated with similar neurologic deficits; differential diagnoses included transverse myelitis and AFM. The Maricopa County Department of Public Health, in cooperation with the Arizona Department of Health Services, CDC, the Translational Genomics Research Institute (TGen, Flagstaff, Arizona), and the acute care hospital, initiated an investigation to confirm AFM cases and identify an etiology. | The 2015 Council of State and Territorial Epidemiologists and CDC case definition for probable AFM requires acute onset of flaccid limb weakness and cerebrospinal fluid (CSF) pleocytosis (CSF white blood cell [WBC] count >5/mm3 when corrected for red blood cells). A confirmed case must have an MRI demonstrating lesions restricted primarily to the gray matter of the spinal cord, in addition to acute onset of flaccid limb weakness (4). Based on medical chart abstraction and review of the MRI images, a CDC neurology subject matter expert verified four confirmed cases of AFM and one probable case. Among the six patients whose cases did not meet the AFM confirmed or probable case definition, two had focal limb weakness and pleocytosis (CSF WBC = 7/mm3 and 22/mm3, respectively), but MRI results indicated alternative etiologies (acute disseminated encephalomyelitis and neuromyelitis optica, respectively). The case that met the probable case definition had pleocytosis (CSF WBC = 7/mm3), but MRI findings were inconsistent with AFM, and no other plausible diagnosis was identified.

In Arizona during 1997-2013, coccidioidomycosis increased from 21 to 90 cases/100,000 population, but coccidioidomycosis-associated deaths remained stable at 3-6 deaths/million population. We used the capture-recapture method by using death certificates and hospital discharge data to more fully estimate the total number of coccidioidomycosis-attributable deaths and compared this with published estimates. Death certificates were included if any cause of death included coccidioidomycosis; hospital discharge data deaths were included if any discharge diagnosis included coccidioidomycosis and laboratory confirmation. Among deaths during 2008-2013, we identified 529 coccidioidomycosis-attributable deaths from death certificates and 560 from hospital discharge data, with 251 deaths identified in both databases. Capture-recapture estimated 1,178 total coccidioidomycosis-attributable deaths, compared with 164 deaths (underlying cause of death) or 529 deaths (any cause of death) on death certificates. Coccidioidomycosis-attributable deaths are underreported from two- to sevenfold on Arizona death certificates, demonstrating an education need for death certifiers to document coccidioidomycosis mortality.

On May 25, 2016, a detainee at a U.S. Immigration and Customs Enforcement (ICE) detention center in Arizona who had been hospitalized with fever and a generalized maculopapular rash was confirmed to have measles by real-time polymerase chain reaction (rPCR). A second case of measles in a staff member was confirmed by rPCR the next day. The privately operated, city-contracted facility housed 1,425 detainees, and employed 510 staff members, including 95 federal ICE staff and 415 contract staff of four distinct employers. Outbreak control measures consisted of administration of measles-mumps-rubella (MMR) vaccine to 1,424 detainees housed at the facility during May 29–31 and isolation of the detainee patient and any additional detainee patients identified during their remaining infectious period (until 4 days after rash onset). Recommendations were made by federal, state, and local public health partners to exclude staff members with measles-compatible symptoms as well as exposed staff members without presumptive evidence of immunity to measles.* | Epidemiologic investigations by local and state health departments and CDC identified 31 total cases of measles in 22 detainees and nine staff members, with rash onsets occurring May 6–June 26 (Figure). Initial reports of rash illness among a few detainees were attributed to varicella (chickenpox) based on clinical presentation; some detainees also reported that they did not initially seek medical attention when they became ill, likely leading to the delay in diagnosing the first few cases of measles. The median detainee patient age was 34 years (range = 19–52 years), and the median staff patient age was 41 years (range = 22–49 years). Seven of the nine ill staff members reported receipt of at least 1 dose of MMR vaccine in the past, but no vaccination records were available at the time the outbreak was recognized. Three of the nine ill staff members received 1 dose of MMR vaccine 7–13 days before becoming ill, suggesting that exposure might have occurred before sufficient immunity developed from vaccination, because the incubation period for measles ranges from 7–21 days.† On June 17 and June 21, MMR staff member vaccination clinics were conducted on-site. Two additional clinics were conducted on July 15 and July 19. Staff members were encouraged to obtain their immunization records and to bring them to the facility to be recorded. Federal personnel policies and contractual agreements that do not require staff members to be vaccinated and the initial unavailability of staff member vaccination records might have contributed to low participation in the first two staff member vaccination clinics; only 120 MMR doses were administered, and 202 (40%) staff members were still considered to not have evidence of measles immunity.