Evaluating TROPOMI and MODIS performance to capture the dynamic of air pollution in São Paulo state: A case study during the COVID-19 outbreak

Atmospheric pollutant data retrieved through satellite sensors are continually used to assess changes in air quality in the lower atmosphere. During the COVID-19 pandemic, several studies started to use satellite measurements to evaluate changes in air quality in many different regions worldwide. However, although satellite data is continuously validated, it is known that its accuracy may vary between monitored areas, requiring regionalized quality assessments. Thus, this study aimed to evaluate whether satellites could measure changes in the air quality of the state of São Paulo, Brazil, during the COVID-19 outbreak; and to verify the relationship between satellite-based data [Tropospheric NO₂ column density and Aerosol Optical Depth (AOD)] and ground-based concentrations [NO₂ and particulate material (PM; coarse: PM₁₀ and fine: PM_2.5)]. For this purpose, tropospheric NO₂ obtained from the TROPOMI sensor and AOD retrieved from MODIS sensor data by using the Multi-Angle Implementation of Atmospheric Correction (MAIAC) algorithm were compared with concentrations obtained from 50 automatic ground monitoring stations. The results showed low correlations between PM and AOD. For PM₁₀, most stations showed correlations lower than 0.2, which were not significant. The results for PM_2.5 were similar, but some stations showed good correlations for specific periods (before or during the COVID-19 outbreak). Satellite-based Tropospheric NO₂ proved to be a good predictor for NO₂ concentrations at ground level. Considering all stations with NO₂ measurements, correlations >0.6 were observed, reaching 0.8 for specific stations and periods. In general, it was observed that regions with a more industrialized profile had the best correlations, in contrast with rural areas. In addition, it was observed about 57% reductions in tropospheric NO₂ throughout the state of São Paulo during the COVID-19 outbreak. Variations in air pollutants were linked to the region economic vocation, since there were reductions in industrialized areas (at least 50% of the industrialized areas showed >20% decrease in NO₂) and increases in areas with farming and livestock characteristics (about 70% of those areas showed increase in NO₂). Our results demonstrate that Tropospheric NO₂ column densities can serve as good predictors of NO₂ concentrations at ground level. For MAIAC-AOD, a weak relationship was observed, requiring the evaluation of other possible predictors to describe the relationship with PM. Thus, it is concluded that regionalized assessment of satellite data accuracy is essential for assertive estimates on a regional/local level. Good quality information retrieved at specific polluted areas does not assure a worldwide use of remote sensor data.

Methodology for conducting a comprehensive product review in managed care

The high degree of complexity of the product-review process and differences in procedures between organizations have resulted in a need for best practices and an overall product-review process to create efficiencies for health care decision makers. In an effort to streamline product-review concepts, this article outlines the different components of the review process, including clinical and economic review, formulary placement determination, and evaluation of alternatives within a drug class. The article also details opportunities for the near future, as technology continues to advance and alignment between medical and pharmacy benefits is desired. DISCLOSURES: Drs Linnerooth, Penley, Ha, and Craven report employment with Xcenda, which provided funding for the manuscript. Drs Sauvageau and Hydery report employment Xcenda, which provided funding for the manuscript, and stock holdings with AmerisourceBergen. Dr Feeney reports support for attending meetings and/or travel provided by Highmark, Inc. Dr Thomas reports receipt of consulting fees from ActiveRADAR, board member roles with ActiveRADAR and RoundtableRx, an adjunct professor role with the University of Minnesota, and stock options and pensions with Eli Lilly and Aetna/CVS. Dr Watkins reports payment or honoraria from ISPOR and for articles written for Value and Outcomes Spotlight, and support for attending meetings and/or travel by AMCP.

How mobility restrictions policy and atmospheric conditions impacted air quality in the State of São Paulo during the COVID-19 outbreak

Mobility restrictions are among actions to prevent the spread of the COVID-19 pandemic and have been pointed as reasons for improving air quality, especially in large cities. However, it is crucial to assess the impact of atmospheric conditions on air quality and air pollutant dispersion in the face of the potential variability of all sources. In this study, the impact of mobility restrictions on the air quality was analyzed for the most populous Brazilian State, São Paulo, severely impacted by COVID-19. Ground-based air quality data (PM₁₀, PM_2.5, CO, SO₂, NO_x, NO₂, NO, and O₃) were used from 50 automatic air quality monitoring stations to evaluate the changes in concentrations before (January 01 - March 25) and during the partial quarantine (March 16 - June 30). Rainfall, fires, and daily cell phone mobility data were also used as supplementary information to the analyses. The Mann-Whitney U test was used to assess the heterogeneity of the air quality data during and before mobility restrictions. In general, the results demonstrated no substantial improvements in air quality for most of the pollutants when comparing before and during restrictions periods. Besides, when the analyzed period of 2020 is compared with the year 2019, there is no significant air quality improvement in the São Paulo State. However, special attention should be given to the Metropolitan Area of São Paulo (MASP), due to the vast population residing in this area and exposed to air pollution. The region reached an average decrease of 29% in CO, 28% in NO_x, 40% in NO, 19% in SO₂, 15% in PM_2.5, and 8% in PM₁₀ concentrations during the mobility restrictions period compared to the same period in 2019. The only pollutant that showed an increase in concentration was ozone, with a 20% increase compared to 2019 during the mobility restrictions period. Before the mobility restrictions period, the region reached an average decrease of 30% in CO, 39% in NO_x, 63% in NO, 12% in SO₂, 23% in PM_2.5, 18% in PM₁₀, and 16% in O₃ concentrations when compared to the same period in 2019. On the other hand, Cubatão, a highly industrialized area, showed statistically significant increases above 20% for most monitored pollutants in both periods of 2020 compared to 2019. This study reinforces that the main driving force of pollutant concentration variability is the dynamics of the atmosphere at its various time scales. An abnormal rainy season, with above average rainfall before the restrictions and below average after it, generated a scenario in which the probable significant reductions in emissions did not substantially affect the concentration of pollutants.

Outbreak of invasive group A streptococcus infection: contaminated patient curtains and cross-infection on an ear, nose and throat ward

BACKGROUND

Outbreaks of group A streptococcus (GAS) infections may occur in healthcare settings and have been documented in surgical, obstetrics and gynaecology, and burns units. The environment may serve as a reservoir and facilitate transmission via contaminated equipment.

AIM

To describe the investigation and control of an outbreak of healthcare-associated GAS infection on an ear, nose and throat (ENT) ward in a tertiary referral centre.

METHODS

Two patients with laryngeal cancer developed invasive GAS infection (bacteraemia) with associated tracheostomy wound cellulitis within a 48 h period. The outbreak team undertook an investigation involving a retrospective review of GAS cases, prospective case finding, healthcare worker screening and sampling of patient curtains. Immediate control measures included source isolation, a thorough rolling clean with a chlorine-based disinfectant and hydrogen peroxide decontamination of patient equipment.

FINDINGS

Prospective patient screening identified one additional patient with carriage of GAS from a tracheostomy wound swab. Staff screening identified one healthcare worker who acquired GAS during the outbreak and who subsequently developed pharyngitis. Environmental sampling demonstrated that 10 out of 34 patient curtains on the ward were contaminated with GAS and all isolates were typed as emm-1.

CONCLUSION

This is the first outbreak report to demonstrate patient curtains as potential source for GAS cross-transmission, with implications in relation to hand hygiene and frequency of laundering. Based on this report we recommend that during an outbreak of GAS infection all patient curtains should be changed as part of the enhanced decontamination procedures.

The danger of freely rocking cradles

OBJECTIVE

To assist the Adelaide State Coroner with his inquest into the death of two infants in South Australia, and to assist the Department of Public and Consumer Affairs develop Australian Standards for rocking cradles.

METHODOLOGY

A sample of each brand of new cradle commercially available in South Australia was examined. Videotapes were made of 11 healthy infants in rocking cradles to examine how they moved and how they reacted in different positions.

RESULTS

Many cradles had insecure locking pins. Infants in a cradle tilted at 10 degrees greater, face down with the side of the face against the bars, and an aim trapped between the body and bars or through the bars, were unable to obtain a clear airway unless a dummy was in the mouth.

CONCLUSIONS

Infants should never be left unattended in freely rocking cradles. Australian Standards should recommend locking pins be bolted into place and that cradles cannot tilt to greater than 5 degrees.

Nasal continuous positive airway pressure in decompensated hypercapnic respiratory failure as a complication of sleep apnea

Cardiopulmonary failure resulting from progression of obstructive sleep apnea (OSA) is treated with endotracheal intubation and mechanical ventilation. This study was conducted to determine whether the use of nasal continuous positive airway pressure (CPAP) would rapidly reverse changes in mental status and hypercapnic acidosis in such patients with decompensated hypercapnic respiratory failure resulting from OSA. Six morbidly obese patients (mean weight, 159 +/- 19 kg) were treated with nasal CPAP and supplemental oxygen. Within 24 h of this treatment, there was a significant increase in pH, from a baseline mean of 7.23 +/- 0.03 to 7.35 +/- 0.01 (p < 0.01), and the mean PaCO2 fell from 80 +/- 4 mm Hg to 64 +/- 4 mm Hg (p < 0.01). In addition, there was a dramatic improvement in mental status within 24 h of therapy with nasal CPAP. None of the patients required intubation and mechanical ventilation. There were no complications attributable to the CPAP delivered by nasal mask. We conclude that CPAP delivered by nasal mask can be safe and effective in rapidly reversing changes in mental status and hypercapnic acidosis in this group of patients with severe respiratory failure, and nasal CPAP obviates the need for endotracheal intubation and mechanical ventilation.

Effects of fast neutrons on the eye

The study of 93 eyes receiving neutron irradiation establishes the character of the ophthalmic complications of neutron. Significant changes are produced in the eyelids, conjunctiva, and cornea, but the production of cataract is relatively unimportant. No reaction was seen after neutron treatment that had not already been seen after chi or gamma radiation. That the unavoidable damage is similar to that reported with other forms of radiation, and not worse, is an important finding in view of the statistically significant benefit of neutron treatment to patients in a controlled clinical trial of advanced tumours of the head and neck (Catterall and others, 1975). The observations indicate that the improved cure rates with neutrons are not obtained at the expense of inflicting greater damage to normal structures. This investigation has also shown that the neutron effects of treating these very extensive tumours are acceptable and that, with carefully measured doses, they are predictable. The dose-response relationship in categories of clinical effect for a smaller series of patients, reported in Table 1 of our preliminary communication (Brown and other, 1976), is confirmed.