The Distribution of Fecal Contamination in an Urbanized Tropical Lake and Incidence of Acute Diarrheal Disease

Aquatic ecosystems of tropical countries are vulnerable to fecal contamination that could cause spikes in the incidences of acute diarrheal disease (ADD) and challenge public health management systems. Vembanad lake, situated along the southwest coast of India, was monitored for one year (2018-2019). Escherichia coli, an indicator of fecal contamination, was prevalent in the lake throughout the year. Multiple antibiotic resistance among more than 50% of the E. coli isolates adds urgency to the need to control this contamination. The high abundance of E. coli and incidence of ADD were recorded during the early phase of the southwest monsoon (June-July), prior to the once-in-a-century floods that affected the region in the later phase (August). The extent of inundation in the low-lying areas peaked in August, but E. coli in the water peaked in July, suggesting that contamination occurred even prior to extreme flooding. During the COVID-19-related lockdown in March-May 2021, fecal contamination in the lake and incidence of ADD reached minimum values. These results indicate the need for improving sewage treatment facilities and city planning in flood-prone areas to avoid the mixing of septic sewage with natural waters during extreme climate events or even during the normal monsoon.

The Distribution of Fecal Contamination in an Urbanized Tropical Lake and Incidence of Acute Diarrheal Disease

Aquatic ecosystems of tropical countries are vulnerable to fecal contamination that could cause spikes in the incidences of acute diarrheal disease (ADD) and challenge public health management systems. Vembanad lake, situated along the southwest coast of India, was monitored for one year (2018-2019). Escherichia coli, an indicator of fecal contamination, was prevalent in the lake throughout the year. Multiple antibiotic resistance among more than 50% of the E. coli isolates adds urgency to the need to control this contamination. The high abundance of E. coli and incidence of ADD were recorded during the early phase of the southwest monsoon (June-July), prior to the once-in-a-century floods that affected the region in the later phase (August). The extent of inundation in the low-lying areas peaked in August, but E. coli in the water peaked in July, suggesting that contamination occurred even prior to extreme flooding. During the COVID-19-related lockdown in March-May 2021, fecal contamination in the lake and incidence of ADD reached minimum values. These results indicate the need for improving sewage treatment facilities and city planning in flood-prone areas to avoid the mixing of septic sewage with natural waters during extreme climate events or even during the normal monsoon. © 2023 American Chemical Society.

Advances in photodynamic antimicrobial chemotherapy

Photodynamic therapy (PDT) and photodynamic antimicrobial chemotherapy (PACT) combine light and photosensitizers to treat cancers and microbial infections, respectively. In PACT, the excitation of a photosensitizer drug with appropriate light generates reactive oxygen species (ROS) that kill pathogens in the proximity of the drug. PACT has considerably advanced with new light sources, biocompatible photosensitizers, bioconjugate methods, and efficient ROS production. The PACT technology has evolved to compete with or replace antibiotics, reducing the burden of antibiotic resistance. This review updates recent advances in PACT, with special references to light sources, photosensitizers, and emerging applications to microbial infestations. We also discuss PACT applied to COVID-19 causing SARS-CoV-2 treatment and disinfecting food materials and water. Finally, we discuss the pathogen selectivity and efficiency of PACT. © 2021 Elsevier B.V.

Physical activity and mental well-being under COVID-19 lockdown: a cross-sectional multination study.

BACKGROUND: COVID-19 lockdowns have reduced opportunities for physical activity (PA) and encouraged more sedentary lifestyles. A concomitant of sedentariness is compromised mental health. We investigated the effects of COVID-19 lockdown on PA, sedentary behavior, and mental health across four Western nations (USA, UK, France, and Australia). METHODS: An online survey was administered in the second quarter of 2020 (N = 2541). We measured planned and unplanned dimensions of PA using the Brunel Lifestyle Physical Activity Questionnaire and mental health using the 12-item General Health Questionnaire. Steps per day were recorded only from participants who used an electronic device for this purpose, and sedentary behavior was reported in hours per day (sitting and screen time). RESULTS: In the USA and Australia samples, there was a significant decline in planned PA from pre- to during lockdown. Among young adults, Australians exhibited the lowest planned PA scores, while in middle-aged groups, the UK recorded the highest. Young adults exhibited the largest reduction in unplanned PA. Across nations, there was a reduction of ~ 2000 steps per day. Large increases in sedentary behavior emerged during lockdown, which were most acute in young adults. Lockdown was associated with a decline in mental health that was more pronounced in women. CONCLUSIONS: The findings illustrate the deleterious effects of lockdown on PA, sedentary behavior, and mental health across four Western nations. Australian young and lower middle-aged adults appeared to fare particularly badly in terms of planned PA. The reduction in steps per day is equivalent to the non-expenditure of ~ 100 kcal. Declines in mental health show how harmful lockdowns can be for women in particular.

When Natural Hazards Intersect with Public Health: A Preliminary Exploration of the Impact of Bushfires and the COVID-19 Pandemic on Australian Coastal Drowning Fatalities.

Natural hazards combined with the COVID-19 pandemic have had significant global impacts to the community and the environment. This study explores the impact of the Australian 2019/20 bushfires followed by the COVID-19 pandemic on unintentional coastal drowning fatalities. Fatality data were collated using triangulation methodology. Percentage change in coastal drowning fatalities between 2019/20 financial year (FY) and the 15FY annual average (2004/5-2018/19) were calculated for the dominant bushfire period (August 2019-February 2020 inclusive) and COVID-19 restrictions in place for 2019/20FY (March-June 2020 inclusive). Relative risk (RR; with 95% confidence intervals [CI]) of coastal drowning was calculated against the average for overall, bushfire and COVID-19 periods, using coastal participation data as the denominator, weighted for the predicted decrease in the use of outdoor coastal areas due to these widespread events. Coastal drowning fatalities increased in 2019/20FY by 9% overall (bushfires: 6%; COVID-19: 9%). Swimming/wading drowning fatalities increased during the bushfire period (RR = 2.02; 95% CI: 1.13-3.63), while boating and personal watercraft (PWC)-related fatalities increased during both the bushfire (RR = 2.92; 95% CI: 1.41-6.05) and COVID-19 period (RR = 3.86; 95% CI: 1.64-9.11). Rock fishing fatalities also increased across both the bushfire (RR = 4.19; 95% CI: 1.45-12.07; p = 0.008) and COVID-19 (RR = 3.8;95% CI: 1.24-11.62; p = 0.027) periods. Findings indicate the activity patterns leading to coastal drowning fatalities changed despite significant public health events impacting freedom of movement and thus opportunity for coastal participation. Understanding, and preparing for, the impacts of natural hazards on drowning risk is vital for future preventive efforts.