Effect of mutation and vaccination on spread, severity, and mortality of COVID-19 disease.

Coronavirus disease 2019 (COVID-19) has had different waves within the same country. The spread rate and severity showed different properties within the COVID-19 different waves. The present work aims to compare the spread and the severity of the different waves using the available data of confirmed COVID-19 cases and death cases. Real-data sets collected from the Johns Hopkins University Center for Systems Science were used to perform a comparative study between COVID-19 different waves in 12 countries with the highest total performed tests for severe acute respiratory syndrome coronavirus 2 detection in the world (Italy, Brazil, Japan, Germany, Spain, India, USA, UAE, Poland, Colombia, Turkey, and Switzerland). The total number of confirmed cases and death cases in different waves of COVID-19 were compared to that of the previous one for equivalent periods. The total number of death cases in each wave was presented as a percentage of the total number of confirmed cases for the same periods. In all the selected 12 countries, Wave 2 had a much higher number of confirmed cases than that in Wave 1. However, the death cases increase was not comparable with that of the confirmed cases to the extent that some countries had lower death cases than in Wave 1, UAE, and Spain. The death cases as a percentage of the total number of confirmed cases in Wave 1 were much higher than that in Wave 2. Some countries have had Waves 3 and 4. Waves 3 and 4 have had lower confirmed cases than Wave 2, however, the death cases were variable in different countries. The death cases in Waves 3 and 4 were similar to or higher than Wave 2 in most countries. Wave 2 of COVID-19 had a much higher spread rate but much lower severity resulting in a lower death rate in Wave 2 compared with that of the first wave. Waves 3 and 4 have had lower confirmed cases than Wave 2; that could be due to the presence of appropriate treatment and vaccination. However, that was not reflected in the death cases, which were similar to or higher than Wave 2 in most countries. Further studies are needed to explain these findings.

Effect of different accessory devices on the dose delivered from pressurised metred-dose inhalers.

INTRODUCTIONS: Improved aerosol delivery of bronchodilators to chronic obstructive pulmonary disease (COPD) subjects is a cornerstone in the treatment approach. Drug delivery and response are improved with the use of accessory devices [spacers and valved holding chambers (VHCs)] with metred-dose inhalers (pMDIs). However, different accessory devices are available in the market with different properties that could affect aerosol delivery. Thus, this study aimed to assess the relative lung deposition and systemic bioavailability and compare bronchodilator response of salbutamol delivered using different accessory devices attached to pMDIs. METHODS: Twelve healthy subjects and twelve COPD subjects inhaled 300 µg salbutamol (3 pMDI puffs) using five different accessory devices with either masks or mouthpieces (Able, Aerochamber plus flow Vu, Dolphin chamber, Tipshaler spacer, and modified Drink bottle spacer). Urine samples were collected thirty minutes post-dosing and cumulatively for the next twenty-four hours, to determine and compare the relative lung deposition [0-0.5 hour excretion of urinary salbutamol (USAL0.5)] and systemic bioavailability [0.5-24 hours excretion of urinary salbutamol (USAL24)] of salbutamol from the selected accessory devices. Also, the difference between pre and post-inhalation forced expiratory volume in one second (ΔFEV1 %) of predicted was determined for each accessory device. RESULTS: Urinary excretion of salbutamol (both USAL0.5 and USAL24 samples) in COPD subjects was significantly (P < .05) lower than in healthy subjects for all accessory devices. USAL0.5 and USAL24 in non-antistatic spacers (modified Drink bottle spacer and Dolphin chamber spacers) were significantly lower (P < .05) than that for antistatic spacers (Aerochamber plus flow Vu, Able and Tips-haler). No significant difference in USAL0.5 and USAL24 was observed between facemasks and mouthpieces. There was a significant difference (P < .05) in ΔFEV1 % of predicted values between COPD subjects and healthy subjects. However, within the COPD group and the healthy group there was no significant difference in ΔFEV1 % of predicted values between all accessory devices or between with mouthpiece or with a mask. CONCLUSIONS: COPD subjects had lower aerosol delivered compared with healthy subjects. Anti-static accessory devices delivered a higher amount of aerosol compared with non-antistatic accessory devices. Even though the presence of a significant difference in aerosol delivery between non-antistatic and antistatic accessory devices no significant difference was found in the ΔFEV1 % between all accessory devices.

Comparison between traditional and nontraditional add-on devices used with pressurised metered-dose inhalers.

Add-on devices that are attached to metered-dose inhalers (MDIs) were introduced to improve aerosol delivery. The objective of this study was to determine the efficacy of drug delivery from an MDI when attached to different add-on devices at different inhalation volumes. The total emitted dose (TED) of salbutamol was estimated for the MDI alone and the MDI connected to five different add-on devices (Able valved holding chamber, Tips-haler valved holding chamber, Aerochamber plus flow Vu valved holding chamber, Dolphin chamber, and a handmade water bottle spacer), at inhalation flow of 28.3 L·min-1 with flow volume of 1, 2 and 4 L, assuming young child (aged <6 years), old child (>6 years) and adult inhalation volumes, respectively. The TED% ranged between 84.1% and 87.2% at all inhalation volumes from the MDI alone, which was significantly greater than all MDI add-on device combinations (p<0.05). The TED% delivered to MDI sampling apparatus by a homemade water bottle spacer and Dolphin chamber, as non-antistatic add-on devices, ranged between 30.5% and 35.3%. However, washing these non-antistatic add-on devices with a light detergent before use improved their TED to range between 47.6% and 51.2%. Non-antistatic add-on devices had significantly lower TED (p<0.05) than that delivered by most antistatic add-on devices, which ranged from 51.3% to 71.6%. This study suggests that antistatic add-on devices delivered much more aerosol than non-antistatic add-on devices. However, it may be advised to still use a non-antistatic add-on device, for the sake of solving the coordination problem, and wash it with light detergent before use to improve TED.

The Impact of Adding a Training Device to Familiar Counselling on Inhalation Technique and Pulmonary Function of Asthmatics.

INTRODUCTION: We have investigated the effect of adding a pressurized metered dose inhaler (pMDI) training device to verbal counselling on pulmonary function and inhalation technique. METHODS: A total of 304 adult asthmatic subjects (> 18 years old) were enrolled in a 3-month study of assessment and education. They were divided into an investigation group (Trainhaler plus Flo-Tone and verbal counselling, n = 261, mean age 49.2 years) and a control group (verbal counselling only, n = 43, mean age 48.7 years). Pulmonary function and inhalation technique were evaluated, mistakes noted, and the correct technique advised at three consecutive monthly visits. Visits also included verbal pMDI counselling (both groups) and training device coaching (investigation group). RESULTS: By visit 2, the mean number of technique errors decreased significantly (p < 0.05) in both groups (investigation group p < 0.001). The investigation group demonstrated a marked decrease in the frequency of the critical error of maintaining a slow inhalation rate until the lungs are full-a technique difficult to learn via verbal counselling alone. The improvement in pulmonary function was significant from the second clinic visit in the investigation group (p < 0.05) and from the third visit in both groups (p < 0.001). CONCLUSIONS: Use of a training device combined with verbal counselling improved inhalation technique. An earlier, significant improvement was also noted in pulmonary function.