Mycoplasma pneumoniae outbreak in a long-term care facility--Nebraska, 2014.

On June 20, 2014, a Nebraska long-term care facility notified the East Central District Health Department (ECDHD) and Nebraska Department of Health and Human Services (NDHHS) of an outbreak of respiratory illness characterized by cough and fever in 22 residents and resulting in four deaths during the preceding 2 weeks. To determine the etiologic agent, identify additional cases, and implement control measures, Nebraska and CDC investigators evaluated the facility's infection prevention measures and collected nasopharyngeal (NP) and oropharyngeal (OP) swabs or autopsy specimens from patients for real-time polymerase chain reaction (PCR) testing at CDC. The facility was closed to new admissions until 1 month after the last case, droplet precautions were implemented, ill residents were isolated, and group activities were canceled. During the outbreak, a total of 55 persons experienced illnesses that met the case definition; 12 were hospitalized, and seven died. PCR detected Mycoplasma pneumoniae DNA in 40% of specimens. M. pneumoniae should be considered a possible cause of respiratory illness outbreaks in long-term care facilities. Morbidity and mortality from respiratory disease outbreaks at long-term care facilities might be minimized if facilities monitor for respiratory disease clusters, report outbreaks promptly, prioritize diagnostic testing in outbreak situations, and implement timely and strict infection control measures to halt transmission.

KPC-4 Is encoded within a truncated Tn4401 in an IncL/M plasmid, pNE1280, isolated from Enterobacter cloacae and Serratia marcescens.

We describe the transfer of bla(KPC-4) from Enterobacter cloacae to Serratia marcescens in a single patient. DNA sequencing revealed that KPC-4 was encoded on an IncL/M plasmid, pNE1280, closely related to pCTX-M360. Further analysis found that KPC-4 was encoded within a novel Tn4401 element (Tn4401f) containing a truncated tnpA and lacking tnpR, ISKpn7 left, and Tn4401 IRL-1, which are conserved in other Tn4401 transposons. This study highlights the continued evolution of Tn4401 transposons and movement to multiple plasmid backbones that results in acquisition by multiple species of Gram-negative bacilli.

Association between swimming pool operator certification and reduced pool chemistry violations--Nebraska, 2005-2006.

Previous studies have recommended mandatory education for all public pool operators, but substantiating data are limited. This study evaluates associations between pool operator certification and chemistry violations by using 2005-2006 Nebraska routine pool inspection reports. Training and certification for nonmunicipal pool operators are only required in two Nebraska counties. Free chlorine violations for nonmunicipal pool inspections were compared in counties with and without certified operator requirements. To control for water supply pH, inspections from nonmunicipal pools with shared-source water in two counties (one requiring certification) were compared for concurrent pH and free chlorine violations. Compared with locations that require certified operators, free chlorine violations and concurrent pH and free chlorine violations were twice as likely in locations without certification. As a result, pools without required operator certification might pose greater health risks. These results demonstrate the benefit of requiring pool operator certification to help prevent recreational water illnesses.

Sensitivity of second-generation enzyme immunoassay for detection of hepatitis C virus infection among oncology patients.

BACKGROUND: The second-generation hepatitis C virus (HCV) enzyme immunoassay (EIA 2), an antibody-detection test, has high sensitivity and is one of the recommended screening tests for detecting HCV infection in the United States. However, its sensitivity among oncology patients is unknown. OBJECTIVE: Assess the EIA 2 sensitivity among a group of oncology patients at a Nebraska clinic where an HCV outbreak occurred during 2000-2001 using nucleic acid testing (NAT) and recombinant immunoblot assay (RIBA) as the gold standards. STUDY DESIGN: Serum specimens were collected from patients 16 months after transmission had stopped. We tested the specimens using EIA 2 (Abbott HCV EIA 2.0), a NAT assay based on transcription-mediated amplification (TMA) (Gen-Probe TMA assay) and RIBA (Chiron RIBA HCV 3.0 SIA). HCV infection was defined as a positive RIBA or TMA test in an oncology patient. Alanine aminotransferase (ALT) levels were determined in EIA 2-negative/TMA-positive samples. RESULTS: A total of 264 samples were included in the study. We identified 92 HCV infections, 76 of which were Abbott EIA 2 positive. Abbott EIA 2 sensitivity was 83% (76/92), lower than that reported among healthy adults (90%) (p=0.01) and poor sensitivity was associated with receipt of chemotherapy during the outbreak period (p=0.02). Only 1 (6%) of the 16 EIA 2-negative cases had elevated ALT. CONCLUSIONS: In this study, EIA 2 sensitivity among oncology patients was lower than that previously reported among immunocompetent persons. Impaired antibody production related to cancer and/or chemotherapy might explain the reduced sensitivity. These findings indicate that, when assessing HCV status in oncology patients, a NAT test should be routinely considered in addition to EIA.

An outbreak of hepatitis C virus infections among outpatients at a hematology/oncology clinic.

BACKGROUND: Approximately 2.7 million persons in the United States have chronic hepatitis C virus (HCV) infection. Health care-associated HCV transmission can occur if aseptic technique is not followed. The authors suspected a health care-associated HCV outbreak after the report of 4 HCV infections among patients at the same hematology/oncology clinic. OBJECTIVE: To determine the extent and mechanism of HCV transmission among clinic patients. DESIGN: Epidemiologic analysis through a cohort study. SETTING: Hematology/oncology clinic in eastern Nebraska. PARTICIPANTS: Patients who visited the clinic from March 2000 through December 2001. MEASUREMENTS: HCV infection status, relevant medical history, and clinic-associated exposures. Bivariate analysis and logistic regression were used to identify risk factors for HCV infection. RESULTS: Of 613 clinic patients contacted, 494 (81%) underwent HCV testing. The authors documented infection in 99 patients who lacked previous evidence of HCV infection; all had begun treatment at the clinic before July 2001. Hepatitis C virus genotype 3a was present in all 95 genotyped samples and presumably originated from a patient with chronic hepatitis C who began treatment in March 2000. Infection with HCV was statistically significantly associated with receipt of saline flushes (P < 0.001). Shared saline bags were probably contaminated when syringes used to draw blood from venous catheters were reused to withdraw saline solution. The clinic corrected this procedure in July 2001. LIMITATION: The delay between outbreak and investigation (>1 year) may have contributed to an underestimate of cases. CONCLUSIONS: This large health care-associated HCV outbreak was related to shared saline bags contaminated through syringe reuse. Effective infection-control programs are needed to ensure high standards of care in outpatient care facilities, such as hematology/oncology clinics.

A cluster of dengue cases in American missionaries returning from Haiti, 2010.

Dengue is an acute febrile illness caused by four mosquito-borne dengue viruses (DENV-1 to -4) that are endemic throughout the tropics. After returning from a 1-week missionary trip to Haiti in October of 2010, 5 of 28 (18%) travelers were hospitalized for dengue-like illness. All travelers were invited to submit serum specimens and complete questionnaires on pre-travel preparations, mosquito avoidance practices, and activities during travel. DENV infection was confirmed in seven (25%) travelers, including all travelers that were hospitalized. Viral sequencing revealed closest homology to a 2007 DENV-1 isolate from the Dominican Republic. Although most (88%) travelers had a pre-travel healthcare visit, only one-quarter knew that dengue is a risk in Haiti, and one-quarter regularly used insect repellent. This report confirms recent DENV transmission in Haiti. Travelers to DENV-endemic areas should receive dengue education during pre-travel health consultations, follow mosquito avoidance recommendations, and seek medical care for febrile illness during or after travel.

Pediatric influenza-associated myositis - Nebraska, 2001-2007.

OBJECTIVE: Influenza-associated myositis (IAM), characterized by severe lower-extremity myalgia and reluctance to walk, is a complication of influenza among children. We investigated IAM in Nebraska during six influenza seasons, 2001-2007. METHODS: During 2006-2007, we requested reports of severe influenza illness among persons aged <18 years and investigated medical records to identify and confirm IAM cases defined as severe myalgia with elevated serum creatinine kinase level in a patient aged <18 years, occurring within 7 days of laboratory confirmed influenza illness onset. Statewide hospital discharge data (HDD) were reviewed to identify retrospectively confirmed IAM cases during 2006-2007 and five previous seasons, by using surveillance data to define periods of influenza activity. Statewide IAM incidence was estimated for 2001-2002 through 2006-2007. RESULTS: During 2006-2007, a total of 13 IAM cases were confirmed by enhanced surveillance. Median age was 6 years (range, 4-11 years). Influenza diagnosis was established by viral isolation from six patients (one influenza A and five influenza B) and rapid diagnostic tests for seven. Twelve (92%) patients, including one who died, were hospitalized for a median of 3 days (range, 1-4 days). Review of HDD identified 12 retrospectively confirmed IAM cases during 2006-2007, including four not reported through enhanced surveillance, and only one during five previous seasons (2003-2004). The HDD-derived, retrospectively confirmed statewide IAM incidence estimates/100,000 population aged <18 years were 2.693 and 0.225 during 2006-2007 and 2003-2004, respectively. CONCLUSION: An IAM epidemic occurred in Nebraska during the 2006-2007 influenza season.

Population-based estimates of Methicillin-Resistant Staphylococcus Areus (MRSA) infections among high school athletes--Nebraska, 2006-2008.

Methicillin-resistant Staphylococcus aureus (MRSA) is an emerging cause of skin and soft-tissue infections among athletes. To determine statewide incidence among high school athletes, we surveyed all 312 Nebraska high schools regarding sport programs offered, program-specific participation numbers, number of athletes with physician-diagnosed MRSA infections, and athlete's sport at infection onset. Among 271 (86.9%) schools responding, MRSA infections were reported among one or more athletes by 4.4% (12/270) and 14.4% (39/271) during school years 2006-2007 and 2007-2008, respectively. From 2006-2007 to 2007-2008, MRSA incidence per 10,000 wrestlers increased from 19.6 to 60.1, and incidence per 10,000 football players increased from 5.0 to 25.1. We did not identify differences in distribution of MRSA infections on the basis of grade, school enrollment, location, or number of participants per team. Incidence of reported MRSA infections among football players and wrestlers was substantially higher during 2007-2008, compared with 2006-2007.

Long-term persistence of mumps antibody after receipt of 2 measles-mumps-rubella (MMR) vaccinations and antibody response after a third MMR vaccination among a university population.

BACKGROUND: High attack rates among vaccinated young adults reported during the 2006 mumps outbreak in the United States heightened concerns regarding mumps vaccine failure. METHODS: Serum specimens from university students and staff were tested for mumps immunoglobulin (Ig) G by enzyme immunoassay (EIA). A subset of participants vaccinated for < or =5 years and > or =15 years were tested by neutralizing antibody (NA) assay. Persons seronegative by EIA were offered a third dose of measles-mumps-rubella vaccine (MMR3), and serum specimens were obtained 7-10 days and 2-3 months after its administration. RESULTS: Overall, 94% (95% confidence interval [CI], 91%-96%) of the 440 participants were seropositive. No differences existed in seropositivity rates by sex, age, age at receipt of the second dose of MMR vaccine (MMR2), or time since receipt of MMR2 (P = .568). The geometric mean titer (GMT) of NA among persons vaccinated with MMR2 during the previous 1-5 years was 97 (95% CI, 64-148), whereas, among those vaccinated > or =15 years before blood collection, the GMT was 58 (95% CI, 44-76) (P = .065). After MMR3, 82% (14/17) and 91% (10/11) seroconverted in 7-10 days and 2-3 months, respectively. CONCLUSIONS: Lower levels of NA observed among persons who received MMR2 > or =15 years ago demonstrates antibody decay over time. MMR3 vaccination of most seronegative persons marked the capacity to mount an anamnestic response.

West Nile virus blood transfusion-related infection despite nucleic acid testing.

BACKGROUND: A case of West Nile virus (WNV) encephalitis associated with transfusion of blood that did not react when tested for WNV by minipool (MP) nucleic acid testing (NAT) is described. A Nebraska man developed clinical encephalitis 13 days after surgery and transfusion of 26 blood components. Antibody testing confirmed WNV infection. An investigation was initiated to determine the source of this infection. STUDY DESIGN AND METHODS: The patient's family members were interviewed to identify risk factors for WNV infection. Residual samples were retested for WNV RNA using transcription-mediated amplification (TMA) assay and two polymerase chain reaction (PCR) assays. Blood donors' follow-up serum samples were collected. All samples were tested for WNV-specific immunoglobulin M antibodies. RESULTS: The patient's family denied recent mosquito exposure. The 20 blood components collected after July 2003 did not react when tested for WNV in a six-member MP-NAT at the time of donation. Retrospective individual testing identified one sample as WNV-reactive by the TMA assay and one of the PCR assays. Seroconversion was demonstrated in the donor associated with this sample. CONCLUSION: WNV RNA detection by individual donation NAT demonstrates viremic blood escaping MP-NAT and supports transfusion-related WNV transmission. MP-NAT may not detect all WNV-infected blood donors, allowing WNV transmission to continue at low levels. WNV NAT assays might vary in sensitivity and pooling donations could further impact test performance. Understanding MP NAT limitations can improve strategies to maintain safety of the blood supply in the United States.