Large Community Outbreak of Legionnaires Disease Potentially Associated with a Cooling Tower - Napa County, California, 2022.

Legionnaires disease is a serious infection acquired by inhalation of water droplets from human-made building water systems that contain Legionella bacteria. On July 11 and 12, 2022, Napa County Public Health (NCPH) in California received reports of three positive urinary antigen tests for Legionella pneumophila serogroup 1 in the town of Napa. By July 21, six Legionnaires disease cases had been confirmed among Napa County residents, compared with a baseline of one or two cases per year. NCPH requested assistance from the California Department of Public Health (CDPH) and CDC to aid in the investigations. Close temporal and geospatial clustering permitted a focused environmental sampling strategy of high-risk facilities which, coupled with whole genome sequencing results from samples and investigation of water system maintenance, facilitated potential linking of the outbreak with an environmental source. NCPH, with technical support from CDC and CDPH, instructed and monitored remediation practices for all environmental locations that tested positive for Legionella. The investigation response to this community outbreak illustrates the importance of interdisciplinary collaboration by public health agencies, laboratory support, timely communication with the public, and cooperation of managers of potentially implicated water systems. Timely identification of possible sources, sampling, and remediation of any facility testing positive for Legionella is crucial to interrupting further transmission.

A Case of Persistent and Possibly Treatment Resistant Pharyngeal Gonorrhea.

An HIV-negative man with pharyngeal gonorrhea had a positive test-of-cure (nucleic acid amplification test) result 7 days after treatment with ceftriaxone/azithromycin. Neisseria gonorrhoeae Multi-Antigen Sequencing Type 1407 and mosaic pen A (XXXIV) gene were identified in the test-of-cure specimen, and culture was negative. Retreatment with ceftriaxone 500 mg intramuscularly plus azithromycin 2 g orally yielded a negative test-of-cure result.

HIV-1 RNA and viral load.

Viral load monitoring has become the standard of care in clinical practice to assess risk for disease progression and to monitor treatment response. Furthermore, viral load monitoring has contributed greatly to the understanding of HIV disease pathogenesis and response to various antiretroviral regimens, and has broadened its applications to include blood bank screening. The assays that are currently available are more sensitive, precise, and robust. There is now a better understanding of their limitations and the clinical scenarios and assay performance issues that result in variations of viral load results.

Proteomic analysis of serum cytokine levels in response to highly active antiretroviral therapy (HAART).

A 30-cytokine protein microarray was used to screen for cytokine profile changes in HIV-infected patients in response to highly active antiretroviral therapy (HAART). Serum cytokines showing significant changes were confirmed by enzyme immunoassay. Monokine induced by gamma-interferon (MIG) and interferon-inducible protein-10 (IP-10) levels significantly decreased after 24 weeks of HAART. Protein microarrays are useful for initial screening of novel cytokine expression. Further studies are needed to elucidate the role of MIG and IP-10 in response to HAART.

Alterations in the thickness of motor cortical subregions after motor-skill learning and exercise.

Behavioral manipulations such as housing in an enriched environment have been shown to increase brain weight and visual cortical thickness. The present study was designed to test whether skill learning or repetitive movements can alter the thickness of the motor cortex. One group of 6-mo-old Long-Evans female rats learned motor skills on an obstacle course that increased in difficulty over training and required balance and coordination. A second group ran voluntarily in exercise wheels attached to their home cage but had little opportunity for skill learning. The third group was handled daily but received no opportunity for learning or exercise. Each condition lasted 26-29 d. The skill-learning and exercise conditions had greater heart weight, and the exercise condition had greater adrenal gland weights than controls. The thickness of the motor cortex was measured in four coronal planes between -2.33 mm to -0.3 mm from bregma. Regions of interest that corresponded to published maps of forelimb and hind-limb representations were analyzed together. Rats in the skill-learning condition had significantly thicker medial cortical areas in the two anterior planes (-0.8 and -0.3 mm from bregma). These regions correspond to previously mapped hind-limb representations. The exercise group had greater thickness of the medial region at -0.8 mm from bregma. Cortical thickness in all conditions varied significantly along the medial to lateral axis. For both treatments, the effects were restricted to medial and anterior regions of interest rather than posterior or lateral regions of interest. The results indicate that robust exercise, in addition to skill learning, is capable of altering the thickness of the motor cortex, but that the effects are restricted rather than distributed within the regions studied.