Impact of acute temperature and air pollution exposures on adult lung function: A panel study of asthmatics.

BACKGROUND: Individuals with respiratory conditions, such as asthma, are particularly susceptible to adverse health effects associated with higher levels of ambient air pollution and temperature. This study evaluates whether hourly levels of fine particulate matter (PM2.5) and dry bulb globe temperature (DBGT) are associated with the lung function of adult participants with asthma. METHODS AND FINDINGS: Global positioning system (GPS) location, respiratory function (measured as forced expiratory volume at 1 second (FEV1)), and self-reports of asthma medication usage and symptoms were collected as part of the Exposure, Location, and Lung Function (ELF) study. Hourly ambient PM2.5 and DBGT exposures were estimated by integrating air quality and temperature public records with time-activity patterns using GPS coordinates for each participant (n = 35). The relationships between acute PM2.5, DBGT, rescue bronchodilator use, and lung function collected in one week periods and over two seasons (summer/winter) were analyzed by multivariate regression, using different exposure time frames. In separate models, increasing levels in PM2.5, but not DBGT, were associated with rescue bronchodilator use. Conversely DBGT, but not PM2.5, had a significant association with FEV1. When DBGT and PM2.5 exposures were placed in the same model, the strongest association between cumulative PM2.5 exposures and the use of rescue bronchodilator was identified at the 0-24 hours (OR = 1.030; 95% CI = 1.012-1.049; p-value = 0.001) and 0-48 hours (OR = 1.030; 95% CI = 1.013-1.057; p-value = 0.001) prior to lung function measure. Conversely, DBGT exposure at 0 hours (ß = 3.257; SE = 0.879; p-value>0.001) and 0-6 hours (ß = 2.885; SE = 0.903; p-value = 0.001) hours before a reading were associated with FEV1. No significant interactions between DBGT and PM2.5 were observed for rescue bronchodilator use or FEV1. CONCLUSIONS: Short-term increases in PM2.5 were associated with increased rescue bronchodilator use, while DBGT was associated with higher lung function (i.e. FEV1). Further studies are needed to continue to elucidate the mechanisms of acute exposure to PM2.5 and DBGT on lung function in asthmatics.

The Stability of an Isolate of the SARS-CoV-2 B.1.1.7 Lineage in Aerosols Is Similar to 3 Earlier Isolates.

BACKGROUND: Our laboratory previously examined the influence of environmental conditions on the stability of an early isolate of SARS-CoV-2 (hCoV-19/USA/WA-1/2020) in aerosols generated from culture medium or simulated saliva. However, genetic differences have emerged among SARS-CoV-2 lineages, and it is possible that these differences may affect environmental stability and the potential for aerosol transmission. METHODS: The influence of temperature, relative humidity, and simulated sunlight on the decay of 4 SARS-CoV-2 isolates in aerosols, including 1 belonging to the recently emerged B.1.1.7 lineage, were compared in a rotating drum chamber. Aerosols were generated from simulated respiratory tract lining fluid to represent aerosols originating from the deep lung. RESULTS: No differences in the stability of the isolates were observed in the absence of simulated sunlight at either 20°C or 40°C. However, a small but statistically significant difference in the stability was observed between some isolates in simulated sunlight at 20°C and 20% relative humidity. CONCLUSIONS: The stability of SARS-CoV-2 in aerosols does not vary greatly among currently circulating lineages, including B.1.1.7, suggesting that the increased transmissibility associated with recent SARS-CoV-2 lineages is not due to enhanced survival in the environment.

Ambulatory cardiology telemedicine: a large academic pediatric center experience.

We performed a retrospective study of cardiology telemedicine visits at a large academic pediatric center between 2016 and 2019 (pre COVID-19). Telemedicine patient visits were matched to data from their previous in-person visits, to evaluate any significant differences in total charge, insurance compensation, patient payment, percent reimbursement and zero reimbursement. Miles were measured between patient's home and the address of previous visit. We found statistically significant differences in mean charges of telemedicine versus in-person visits (2019US$) (172.95 vs 218.27, p=0.0046), patient payment for telemedicine visits versus in-person visits (2019US$) (11.13 vs 62.83, p≤0.001), insurance reimbursement (2019US$) (65.18 vs 110.85, p≤0.001) and insurance reimbursement rate (43% vs 61%, p=0.0029). Rate of zero reimbursement was not different. Mean distance from cardiology clinic was 35 miles. No adverse outcomes were detected. This small retrospective study showed cost reduction and a decrease in travel time for families participating in telemedicine visits. Future work is needed to enhance compensation for telemedicine visits.

Increasing Temperature and Relative Humidity Accelerates Inactivation of SARS-CoV-2 on Surfaces.

Coronavirus disease 2019 (COVID-19) was first identified in China in late 2019 and is caused by newly identified severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Previous studies had reported the stability of SARS-CoV-2 in cell culture media and deposited onto surfaces under a limited set of environmental conditions. Here, we broadly investigated the effects of relative humidity, temperature, and droplet size on the stability of SARS-CoV-2 in a simulated clinically relevant matrix dried on nonporous surfaces. The results show that SARS-CoV-2 decayed more rapidly when either humidity or temperature was increased but that droplet volume (1 to 50 µl) and surface type (stainless steel, plastic, or nitrile glove) did not significantly impact decay rate. At room temperature (24°C), virus half-life ranged from 6.3 to 18.6 h depending on the relative humidity but was reduced to 1.0 to 8.9 h when the temperature was increased to 35°C. These findings suggest that a potential for fomite transmission may persist for hours to days in indoor environments and have implications for assessment of the risk posed by surface contamination in indoor environments.IMPORTANCE Mitigating the transmission of SARS-CoV-2 in clinical settings and public spaces is critically important to reduce the number of COVID-19 cases while effective vaccines and therapeutics are under development. SARS-CoV-2 transmission is thought to primarily occur through direct person-to-person transfer of infectious respiratory droplets or through aerosol-generating medical procedures. However, contact with contaminated surfaces may also play a significant role. In this context, understanding the factors contributing to SARS-CoV-2 persistence on surfaces will enable a more accurate estimation of the risk of contact transmission and inform mitigation strategies. To this end, we have developed a simple mathematical model that can be used to estimate virus decay on nonporous surfaces under a range of conditions and which may be utilized operationally to identify indoor environments in which the virus is most persistent.