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In January 2014, members of the Joint Base San Antonio (JBSA)-Lackland, Texas, preventive medicine and public health teams evaluated a U.S. Air Force basic training squadron for potential exposure in sleeping bays to rabies virus carried by Mexican free-tailed bats (Tadarida brasiliensis). Exposure to bats while asleep or otherwise unaware is an important risk factor for rabies in the United States. Over the past several decades, most indigenous human rabies infections in the United States have resulted from the bite of an infected bat, and the bite was not reported in more than half of the cases. Mexican free-tailed bats in Texas often carry rabies virus. Among 8,904 bats tested during 2001-2010, a total of 1,558 (18%) tested positive for rabies. To assess the risk to the Air Force trainees and identify those for whom rabies postexposure prophylaxis (PEP) might be indicated, Lackland preventive medicine and public health teams interviewed 922 persons (866 trainees and 56 instructors) and determined that PEP, consisting of human rabies immune globulin and the 4-dose vaccination series given over 14 days, was indicated for 200 persons (22%). This report describes the public health response to a mass indoor exposure to bats, including group-based rabies risk stratification, adverse reactions to PEP, and infestation remediation. These interventions can be considered for future mass exposures to bats.

Background Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, is endemic to Texas and has significant morbidity associated with its cardiac pathology. The Joint Base San Antonio-Lackland (JBSA) represents a healthcare system with universal coverage to its beneficiaries and its blood bank screens all first-time blood donors for T. cruzi infection. Although there is a published, standardized approach for diagnosis and evaluation of Chagas disease in the United States, adherence to this approach has not been studied. Methods A retrospective chart review was performed on all persons who screened positive for T. cruzi on blood donation at JBSA from 2014 to 2016. Charts were reviewed to determine frequency and results of confirmatory testing, history and physical, EKG, and 30 second rhythm strip; outcomes of these evaluations were ascertained. Chagas disease was considered confirmed on the basis of positive EIA and TESA testing from the CDC and/or two different positive serologic tests. Results Of the 43,402 blood donors at JBSA, 23 screened positive for Chagas disease. Follow-up information was available on 22 (95.7%). Seventeen (77%) were military trainees and 18 (82%) were male. Patients had a mean of 2.5 (range 1–5) additional serologic tests, with 13 different combinations of confirmatory tests ordered, including 17 (77%) who had the initial screening test repeated. Two patients (9%), both from Texas, met criteria for Chagas disease. One of these was diagnosed with cardiomyopathy and underwent administrative separation from the Air Force. Eleven (50%) had Chagas disease excluded on the basis of two negative follow-up tests, and 9 (41%) had one negative follow-up test. All underwent history and physical, 15 (68%) had an EKG, and 5 (22%) had a 30 second rhythm strip. Fourteen (64%) were referred to infectious diseases. Conclusion Among a small cohort of active duty service members who screened positive for T. cruzi infection on blood donation, diagnostic workup, and evaluation varied considerably, despite universal access to no-cost medical care within a single system. Opportunities exist within the military health system to decrease heterogeneity and to improve evaluation of persons who screen positive in the future. Disclosures H. Yun, American Board of Internal Medicine, Infectious Disease Board: Board Member, travel reimbursement, honorarium

Seasonal coastal upwelling was analyzed along the NW African coastline (11-35°N) from 1981 to 2012. Upwelling magnitudes are calculated by wind speed indices, sea-surface temperature indices and inferred from meteorological station, sea-surface height and vertical water column transport data. A permanent annual upwelling regime is documented across 21-35°N and a seasonal regime across 12-19°N, in accordance with the climatology of previous studies. Upwelling regions were split into three zones: (1) the Mauritania-Senegalese upwelling zone (12-19°N), (2) the strong permanent annual upwelling zone (21-26°N) and (3) the weak permanent upwelling zone (26-35°N). We find compelling evidence in our various indices for the Bakun upwelling intensification hypothesis due to a significant coastal summer wind speed increase, resulting in an increase in upwelling-favorable wind speeds north of 20°N and an increase in downwelling-favorable winds south of 20°N. The North Atlantic Oscillation plays a leading role in modifying interannual variability during the other seasons (autumn-spring), with its influence dominating in winter. The East Atlantic pattern shows a strong correlation with upwelling during spring, while El Niño Southern Oscillation and Atlantic Multi-decadal Oscillation teleconnections were not found. A disagreement between observationally-based wind speed products and reanalysis-derived data is explored. A modification to the Bakun upwelling intensification hypothesis for NW Africa is presented, which accounts for the latitudinal divide in summer wind regimes. © 2014 The Authors.

New monthly, long‐running, continuous surface air temperature records for four island chains throughout the Macaronesian biogeographical zone in the North Atlantic Ocean are presented. The records run from 1865 for the Azores and Madeira, 1885 for the Canary Islands and 1895 for Cape Verde. Recent (1981–2010) warming across these islands is significant in summer (JJA) for the Canary Islands, Cape Verde and Madeira, ranging from 0.40 to 0.46 °C per decade. Annually, the temperature trends across this period range from 0.30 to 0.38 °C per decade across all four island chains (significant for all but the Canary Islands), which exceed the station‐based, average global temperature rise by up to 0.10 °C per decade. Precipitation records from multiple islands across Macaronesia are also presented in addition to sea‐level pressure records from the Azores and Cape Verde. Cape Verde wet season (ASO) precipitation is found to have significantly increased at two of our three sites from 1981 to 2010. The Azores, Canary Islands and Madeira precipitation trends display no significant changes, although the three Azores stations display a recent positive tendency. The extended Azores pressure record allows us to construct an entirely station‐based Azores‐Iceland North Atlantic Oscillation index (NAOI) from 1865 to 2012 and extend the daily station‐based index back to 1944, further than the longest previous daily NAOI by 6 years. In addition, we use the sea‐level pressure difference between the Azores and Cape Verde to create a novel method of characterizing trade wind strength across Macaronesia, the Trade Wind index (TWI), which points towards a recent, statistically significant increase (since 1973) throughout the region. Links between the winter and summer NAOI, TWI and Macaronesian temperature and precipitation are explored, as are the differences in warming trends between Macaronesia and analogous subtropical island chains, most of which are found to be warming at slower rates than the Macaronesia stations. © 2013 Royal Meteorological Society