Publications

BACKGROUND

Blood donation screening for human immunodeficiency virus Type 2 (HIV-2) has been in place in the United States since 1992. However, only three HIV-2 antibody-positive donors have been reported to date, all detected via HIV-1 cross-reactivity.

STUDY DESIGN AND METHODS

Here we identify two additional HIV-2-positive donors by routine anti-HIV-1 and anti-HIV-2 screening, including a first-time male donor living in Georgia having recently immigrated to the United States from West Africa (from a 1998 donation) and a Taiwanese female repeat donor (nurse) living in California with no travel outside of Taiwan or apparent connections to West Africa (from a 2015 donation). Neither donor acknowledged any risk factors, and both remained asymptomatic through follow-up. The second donor was further investigated by serologic, molecular, and genomic assays because of her unusual demographics. She was documented to harbor HIV-2 RNA, albeit sporadically by HIV-2-specific nucleic acid tests (35%-100% of replicates) and at very low levels (<9.6 IU/mL). Metagenomic next-generation sequencing (mNGS) confirmed the identification of a Group B HIV-2 strain, with recovered reads covering 46.9% of the predicted genome.

CONCLUSIONS

The estimated frequency of an HIV-2-positive blood donor in the United States is one in 57 million donations. Due to the low frequency and low pathogenicity of HIV-2, public health and blood donation screening efforts must focus on HIV-1 detection and prevention. However, detection of HIV-2 infection in a donor with no apparent link to West Africa suggests that the United States must remain vigilant for HIV-2 virus infections. Ultradeep mNGS may be useful in the future for comprehensive identification of rare transfusion-transmissible agents.

BACKGROUND

Wildfire activity is predicted to increase in many parts of the world due to changes in temperature and precipitation patterns from global climate change. Wildfire smoke contains numerous hazardous air pollutants and many studies have documented population health effects from this exposure.

OBJECTIVES

We aimed to assess the evidence of health effects from exposure to wildfire smoke and to identify susceptible populations.

METHODS

We reviewed the scientific literature for studies of wildfire smoke exposure on mortality and on respiratory, cardiovascular, mental, and perinatal health. Within those reviewed papers deemed to have minimal risk of bias, we assessed the coherence and consistency of findings.

DISCUSSION

Consistent evidence documents associations between wildfire smoke exposure and general respiratory health effects, specifically exacerbations of asthma and chronic obstructive pulmonary disease. Growing evidence suggests associations with increased risk of respiratory infections and all-cause mortality. Evidence for cardiovascular effects is mixed, but a few recent studies have reported associations for specific cardiovascular end points. Insufficient research exists to identify specific population subgroups that are more susceptible to wildfire smoke exposure.

CONCLUSIONS

Consistent evidence from a large number of studies indicates that wildfire smoke exposure is associated with respiratory morbidity with growing evidence supporting an association with all-cause mortality. More research is needed to clarify which causes of mortality may be associated with wildfire smoke, whether cardiovascular outcomes are associated with wildfire smoke, and if certain populations are more susceptible.

CITATION

Reid CE, Brauer M, Johnston FH, Jerrett M, Balmes JR, Elliott CT. 2016. Critical review of health impacts of wildfire smoke exposure. Environ Health Perspect 124:1334-1343; http://dx.doi.org/10.1289/ehp.1409277.