Detection of SARS-CoV-2 in Environment: Current Surveillance and Effective Data Management of COVID-19

Since diagnostic laboratories handle large COVID-19 samples, researchers have established laboratory-based assays and developed biosensor prototypes. Both share the same purpose; to ascertain the occurrence of air and surface contaminations by the SARS-CoV-2 virus. However, the biosensors further utilize internet-of-things (IoT) technology to monitor COVID-19 virus contamination, specifically in the diagnostic laboratory setting. The IoT-capable biosensors have great potential to monitor for possible virus contamination. Numerous studies have been done on COVID-19 virus air and surface contamination in the hospital setting. Through reviews, there are abundant reports on the viral transmission of SARS-CoV-2 through droplet infections, person-to-person close contact and fecal-oral transmission. However, studies on environmental conditions need to be better reported. Therefore, this review covers the detection of SARS-CoV-2 in airborne and wastewater samples using biosensors with comprehensive studies in methods and techniques of sampling and sensing (2020 until 2023). Furthermore, the review exposes sensing cases in public health settings. Then, the integration of data management together with biosensors is well explained. Last, the review ended with challenges to having a practical COVID-19 biosensor applied for environmental surveillance samples.

Impacts of climate change and environmental degradation on children in Malaysia

The impacts of climate change and degradation are increasingly felt in Malaysia. While everyone is vulnerable to these impacts, the health and wellbeing of children are disproportionately affected. We carried out a study composed of two major components. The first component is an environmental epidemiology study comprised of three sub-studies: (i) a global climate model (GCM) simulating specific health-sector climate indices; (ii) a time-series study to estimate the risk of childhood respiratory disease attributable to ambient air pollution; and (iii) a case-crossover study to identify the association between haze and under-five mortality in Malaysia. The GCM found that Malaysia has been experiencing increasing rainfall intensity over the years, leading to increased incidences of other weather-related events. The time-series study revealed that air quality has worsened, while air pollution and haze have been linked to an increased risk of hospitalization for respiratory diseases among children. Although no clear association between haze and under-five mortality was found in the case-crossover study, the lag patterns suggested that health effects could be more acute if haze occurred over a longer duration and at a higher intensity. The second component consists of three community surveys on marginalized children conducted (i) among the island community of Pulau Gaya, Sabah; (ii) among the indigenous Temiar tribe in Pos Kuala Mu, Perak; and (iii) among an urban poor community (B40) in PPR Sg. Bonus, Kuala Lumpur. The community surveys are cross-sectional studies employing a socio-ecological approach using a standardized questionnaire. The community surveys revealed how children adapt to climate change and environmental degradation. An integrated model was established that consolidates our overall research processes and demonstrates the crucial interconnections between environmental challenges exacerbated by climate change. It is recommended that Malaysian schools adopt a climate-smart approach to education to instill awareness of the impending climate change and its cascading impact on children's health from early school age.

The High Occurrence of Multidrug-Resistant Salmonella spp. Isolated from Raw Chicken Meat and Contact Surfaces at Wet Market in Malaysia

Post-slaughter processing steps during poultry meat production contribute to Salmonella contamination and may transmit multidrug-resistant Salmonella to chicken meats and contact surfaces. This study was undertaken to identify Salmonella spp. strains isolated from chicken meats and their contact surfaces, and to determine their antibiotic resistance profiles. A total of 20 samples were collected from raw chicken meat and its contact surfaces from a shop in Pasar Chow Kit, Kuala Lumpur. Identification of presumptive Salmonella colonies was conducted by using biochemical tests and multiplex polymerase chain reaction (PCR). Antibiotic susceptibility test was conducted by using Kirby-Bauer disk diffusion method against 11 antibiotics. Salmonella enterica Group I was only detected in seven samples. The antibiogram testing showed that all the seven Salmonella isolates (100%) were multidrug-resistant and all isolates were resistant to penicillin, chloramphenicol, erythromycin, and tetracycline. Resistance towards trimethoprim-sulfamethoxazole, amoxicillin and ampicillin was observed in four isolates. However, sensitivity was recorded for cephalexin, cefoxitin, cefotaxime, and ceftriaxone in six isolates. The highest multiple antibiotic resistance (MAR) index of 1.00 (resistance to all eleven antibiotics tested) was observed in one isolate (P2) while the lowest MAR index of 0.36 (resistance to four antibiotics tested) was observed in three isolates (CB, M2 and M3). Our results demonstrated that raw chicken and meat contact surface were a source of multidrug-resistant Salmonella and can contribute to significant health concern in Malaysia. Stringent hygienic procedure during chicken meat processing should be therefore be practised.

Cultured C2C12 cell lines as a model for assessment of bacterial attachment to bovine primary muscle cells

The mechanisms of bacterial attachment to meat tissues need to be understood to enhance meat safety interventions. However, little is known about attachment of foodborne pathogens to meat muscle cells. In this study, attachment of six Escherichia coli and two Salmonella strains to primary bovine muscle cells and a cultured muscle cell line, C2C12, was measured, including the effect of temperature. At 37°C, all but one strain (EC623) attached to C2C12 cells, whereas only five of eight strains (M23Sr, H10407, EC473, Sal1729a and Sal691) attached to primary cells. At 10 °C, two strains (H10407 and EC473) attached to C2C12 cells, compared to four strains (M23Sr, EC614, H10407 and Sal1729a) of primary cells. Comparing all strains at both temperatures, EC614 displayed the highest CFU per C2C12 cell (4.60±2.02CFU/muscle cell at 37 °C), whereas greater numbers of M23Sr attached per primary cell (51.88±39.43CFU/muscle cell at 37 °C). This study indicates that primary bovine muscle cells may provide a more relevant model system to study bacterial attachment to beef carcasses compared to cell lines such as C2C12.