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Abstract Background Anemia is common in HIV infection and independently associated with disease progression and mortality. The pathophysiology of HIV-related anemia is not well understood especially in infancy. Methods We conducted a longitudinal cohort study nested within the Zimbabwe Vitamin A for Mothers and Babies Project. We measured hemoglobin, erythropoietin (EPO), serum transferrin receptor (TfR) and serum ferritin at 6 weeks, 3 and 6 months of age and hemoglobin at 9 and 12 months in 3 groups of randomly selected infants: 136 born to HIV-negative mothers, and 99 born to HIV-positive mothers and who were infected themselves by 6 weeks of age, and 324 born to HIV-positive mothers but who did not become infected in the 6 months following birth. Results At one year of age, HIV-positive infants were 5.26 (adjusted odds ratio, P < 0.001) times more likely to be anemic compared to HIV-negative infants. Among, HIV-negative infants, EPO was or tended to be inversely associated with hemoglobin and was significantly positively associated with TfR throughout the first 6 months of life; TfR was significantly inversely associated with ferritin at 6 months; and EPO explained more of the variability in TfR than did ferritin. Among infected infants, the inverse association of EPO to hemoglobin was attenuated during early infancy, but significant at 6 months. Similar to HIV-negative infants, EPO was significantly positively associated with TfR throughout the first 6 months of life. However, the inverse association between TfR and ferritin observed among HIV-negative infants at 6 months was not observed among infected infants. Between birth and 6 months, mean serum ferritin concentration declined sharply (by ~90%) in all three groups of babies, but was significantly higher among HIV-positive compared to HIV-negative babies at all time points. Conclusion HIV strongly increases anemia risk and confounds interpretation of hematologic indicators in infants. Among HIV-infected infants, the EPO response to anemia is attenuated near the time of infection in the first weeks of life, but normalizes by 6 months.

An unprecedented irruption of thousands of Razorbills Alca torda into Florida in winter 2012/13 was followed by a "wreck" of Razorbills and Atlantic Puffins Fratercula arctica in outer Cape Cod, Massachusetts, in January-March 2013. We describe these events using citizen-science sources (eBird and beached-bird surveys) and band recoveries, then we discuss them in relation to extreme weather and oceanographic change. We explored effects on likely source populations using census and monitoring data, along with possible contributions from population increases, reduced food supply, and extreme weather. Winter 2012/13 followed a marine heatwave throughout the northwest Atlantic, whose effects included reduced availability of plankton. We attribute the irruption of Razorbills into Florida partly to delayed effects of Hurricane Sandy, which disrupted their coastal habitat sufficiently to cause starving birds to move south on the Labrador Current as far as Florida. Despite the continuation of anomalously warm ocean temperatures in subsequent years and a reduction in plankton communities in the Bay of Fundy and Gulf of Maine that continues to date, no comparable events have been recorded in subsequent winters; this supports our theory that the delayed effects of Hurricane Sandy contributed to these wrecks. We highlight the power of these datasets to detect and to investigate birds' responses to extreme and anomalous conditions, which in turn provides insight into the dynamics of rapidly changing ecological systems. [ABSTRACT FROM AUTHOR]

Abstract: Background: In several recent papers it has been suggested that HIV prevalence and incidence are declining in Zimbabwe as a result of changing sexual behavior. We provide further support for these suggestions, based on an analysis of more extensive, age-stratified, HIV prevalence data from 1990 to 2009 for perinatal women in Harare, as well as data on incidence and mortality. Methodology/principal findings: Pooled prevalence, incidence and mortality were fitted using a simple susceptible-infected (SI) model of HIV transmission; age-stratified prevalence data were fitted using double-logistic functions. We estimate that incidence peaked at 5.5% per year in 1991 declining to 1% per year in 2010. Prevalence peaked in 1998/9 [35.9% (CI95: 31.3–40.7)] and decreased by 67% to 11.9% (CI95: 10.1–13.8) in 2009. For women <20y, 20–24y, 25–29y, 30–34y and ≥35y, prevalence peaked at 25.4%, 34.2%, 47.1%, 44.0% and 33.5% in 1993, 1996, 1997, 1998 and 1999, respectively, declining thereafter in every age group. Among women <25y, prevalence peaked in 1994 at 28.8% declining thereafter by 69% to 8.9% (CI95: 6.8–11.5) in 2009. Conclusion/significance: HIV prevalence declined substantially among perinatal women in Harare after 1998 consequent upon a decline in incidence starting in the early 1990s. Our model suggests that this was primarily a result of changes in behavior which we attribute to a general increase in awareness of the dangers of AIDS and the ever more apparent increases in mortality. [Copyright &y& Elsevier]

Objectives: The relationship between Fe status and HIV infection is complex and poorly understood. While anaemia is a major complication of HIV infection, higher Fe stores may be associated with disease progression. There is limited and conflicting data available from Africa. Design: Cross-sectional and prospective cohort study. Setting, subjects and methods: We examined the association between postpartum Fe status (Hb, serum ferritin (SF) and transferrin receptor (TfR)) and viral load (VL) and HIV-related mortality in 643 HIV-positive Zimbabwean women over a period of 12 months. Results: In non-anaemic women a log10 increase in SF was associated with a 2·3-fold increase in VL (P=0·019); this association was absent in anaemic women. In prospective analyses, a log10 increase in SF was associated with a 4-fold increase in mortality by 12 months (P=0η002). Hb was negatively associated with VL (P=0·001) and mortality (P=0·047). The adverse associations between SF and both VL and mortality were found at SF concentrations >45 μg/l (P<0·05). Controlling for α1 acid glycoprotein, a marker of inflammation, attenuated the association between both SF and VL and mortality, but these remained significant. Conclusions: These results are consistent with the hypothesis that high Fe stores have adverse consequences in HIV infection. If adverse consequences are real, our data suggest that they occur at SF concentrations exceeding those consistent with adequate Fe nutriture. [ABSTRACT FROM AUTHOR]

Twenty seven babies with severe non-haemolytic hydrops fetalis were born during a 7 1/4 year period (1/1400 total births). Thirteen were live born and admitted to the intensive care nursery, but only three survived. The survivors differed from those live born infants who died in the neonatal period in that the cause of the hydrops was discovered antenatally, their serum concentrations of total protein and albumin were normal, and they had no structural anomaly. A scheme of investigation of the severely hydropic fetus in the antenatal period is outlined and the role of active obstetric management is evaluated. [ABSTRACT FROM AUTHOR]