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Background The global burden of childhood tuberculosis (TB) is estimated to be 0.5 million new cases per year. Human immunodeficiency virus (HIV)-infected children are at high risk for TB. Diagnosis of TB in HIV-infected children remains a major challenge. Methods We describe TB diagnosis and screening practices of pediatric antiretroviral treatment (ART) programs in Africa, Asia, the Caribbean, and Central and South America. We used web-based questionnaires to collect data on ART programs and patients seen from March to July 2012. Forty-three ART programs treating children in 23 countries participated in the study. Results Sputum microscopy and chest Radiograph were available at all programs, mycobacterial culture in 40 (93%) sites, gastric aspiration in 27 (63%), induced sputum in 23 (54%), and Xpert MTB/RIF in 16 (37%) sites. Screening practices to exclude active TB before starting ART included contact history in 41 sites (84%), symptom screening in 38 (88%), and chest Radiograph in 34 sites (79%). The use of diagnostic tools was examined among 146 children diagnosed with TB during the study period. Chest Radiograph was used in 125 (86%) children, sputum microscopy in 76 (52%), induced sputum microscopy in 38 (26%), gastric aspirate microscopy in 35 (24%), culture in 25 (17%), and Xpert MTB/RIF in 11 (8%) children. Conclusions Induced sputum and Xpert MTB/RIF were infrequently available to diagnose childhood TB, and screening was largely based on symptom identification. There is an urgent need to improve the capacity of ART programs in low- and middle-income countries to exclude and diagnose TB in HIV-infected children

During the last deglaciation, Greenland ice core and North Atlantic sediment records exhibit multiple abrupt climate events including the Younger Dryas cold episode (12.9-11.7 ka). However, evidence for the presence of the Younger Dryas in the Gulf of Mexico (GOM) and the relationship between GOM sea surface temperature (SST) and high-latitude climate change is less clear. We present new Mg/Ca-SST records from two varieties of the planktonic foraminifer Globigerinoides ruber (white and pink) to assess northern GOM SST history from approximately 18.4-10.8 ka. Thirty-five accelerator mass spectrometry (AMS) C-14 dates from Orca Basin core MD02-2550 provide excellent age control and document high sedimentation rates (similar to 40 cm/kyr). G. ruber (white and pink) Mg/Ca-SST data exhibit increases (similar to 4.6 +/- 0.6 degrees C and similar to 2.2 +/- 0.5 degrees C, respectively) from at least 17.8-16.6 ka, with nearly decadal resolution that are early relative to the onset of the Bolling-Allerod interstadial. Moreover, G. ruber (white) SST decreases at 16.0-14.7 ka (similar to 1.0 +/- 0.5 degrees C) and 12.8-11.6 ka (similar to 2.4 +/- 0.6 degrees C) correlate to the Oldest and Younger Dryas in Greenland and Cariaco Basin. The G. ruber (pink) SST record, which reflects differences in seasonality and/or depth habitat, is often not in phase with G. ruber (white) and closely resembles Antarctic air temperature records. Overall, it appears that Orca Basin SST records follow Antarctic air temperature early in the deglacial sequence and exhibit enhanced seasonality during Greenland stadials.

During the last deglaciation, Greenland ice core and North Atlantic sediment records exhibit multiple abrupt climate events including the Younger Dryas cold episode (12.9-11.7 ka). However, evidence for the presence of the Younger Dryas in the Gulf of Mexico (GOM) and the relationship between GOM sea surface temperature (SST) and high-latitude climate change is less clear. We present new Mg/Ca-SST records from two varieties of the planktonic foraminifer Globigerinoides ruber (white and pink) to assess northern GOM SST history from approximately 18.4-10.8 ka. Thirty-five accelerator mass spectrometry (AMS) C-14 dates from Orca Basin core MD02-2550 provide excellent age control and document high sedimentation rates (similar to 40 cm/kyr). G. ruber (white and pink) Mg/Ca-SST data exhibit increases (similar to 4.6 +/- 0.6 degrees C and similar to 2.2 +/- 0.5 degrees C, respectively) from at least 17.8-16.6 ka, with nearly decadal resolution that are early relative to the onset of the Bolling-Allerod interstadial. Moreover, G. ruber (white) SST decreases at 16.0-14.7 ka (similar to 1.0 +/- 0.5 degrees C) and 12.8-11.6 ka (similar to 2.4 +/- 0.6 degrees C) correlate to the Oldest and Younger Dryas in Greenland and Cariaco Basin. The G. ruber (pink) SST record, which reflects differences in seasonality and/or depth habitat, is often not in phase with G. ruber (white) and closely resembles Antarctic air temperature records. Overall, it appears that Orca Basin SST records follow Antarctic air temperature early in the deglacial sequence and exhibit enhanced seasonality during Greenland stadials.

During the last deglaciation, Greenland ice core and North Atlantic sediment records exhibit multiple abrupt climate events including the Younger Dryas cold episode (12.9-11.7 ka). However, evidence for the presence of the Younger Dryas in the Gulf of Mexico (GOM) and the relationship between GOM sea surface temperature (SST) and high-latitude climate change is less clear. We present new Mg/Ca-SST records from two varieties of the planktonic foraminifer Globigerinoides ruber (white and pink) to assess northern GOM SST history from approximately 18.4-10.8 ka. Thirty-five accelerator mass spectrometry (AMS) C-14 dates from Orca Basin core MD02-2550 provide excellent age control and document high sedimentation rates (similar to 40 cm/kyr). G. ruber (white and pink) Mg/Ca-SST data exhibit increases (similar to 4.6 +/- 0.6 degrees C and similar to 2.2 +/- 0.5 degrees C, respectively) from at least 17.8-16.6 ka, with nearly decadal resolution that are early relative to the onset of the Bolling-Allerod interstadial. Moreover, G. ruber (white) SST decreases at 16.0-14.7 ka (similar to 1.0 +/- 0.5 degrees C) and 12.8-11.6 ka (similar to 2.4 +/- 0.6 degrees C) correlate to the Oldest and Younger Dryas in Greenland and Cariaco Basin. The G. ruber (pink) SST record, which reflects differences in seasonality and/or depth habitat, is often not in phase with G. ruber (white) and closely resembles Antarctic air temperature records. Overall, it appears that Orca Basin SST records follow Antarctic air temperature early in the deglacial sequence and exhibit enhanced seasonality during Greenland stadials.

Background The global burden of childhood tuberculosis (TB) is estimated to be 0.5 million new cases per year. Human immunodeficiency virus (HIV)-infected children are at high risk for TB. Diagnosis of TB in HIV-infected children remains a major challenge. Methods We describe TB diagnosis and screening practices of pediatric antiretroviral treatment (ART) programs in Africa, Asia, the Caribbean, and Central and South America. We used web-based questionnaires to collect data on ART programs and patients seen from March to July 2012. Forty-three ART programs treating children in 23 countries participated in the study. Results Sputum microscopy and chest Radiograph were available at all programs, mycobacterial culture in 40 (93%) sites, gastric aspiration in 27 (63%), induced sputum in 23 (54%), and Xpert MTB/RIF in 16 (37%) sites. Screening practices to exclude active TB before starting ART included contact history in 41 sites (84%), symptom screening in 38 (88%), and chest Radiograph in 34 sites (79%). The use of diagnostic tools was examined among 146 children diagnosed with TB during the study period. Chest Radiograph was used in 125 (86%) children, sputum microscopy in 76 (52%), induced sputum microscopy in 38 (26%), gastric aspirate microscopy in 35 (24%), culture in 25 (17%), and Xpert MTB/RIF in 11 (8%) children. Conclusions Induced sputum and Xpert MTB/RIF were infrequently available to diagnose childhood TB, and screening was largely based on symptom identification. There is an urgent need to improve the capacity of ART programs in low- and middle-income countries to exclude and diagnose TB in HIV-infected children