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Biology subjects

Pathak, S. B.

Publications and source records attributed to Pathak, S. B..

2 recordsLinked to original sources

Addressing efficacy of everyday hygiene cleansing products in context of sustainable handwashing behavior in the post-pandemic era

Simple hygiene behaviour such as washing hands is key to improving health of individuals and reducing community transmission of communicable diseases such as respiratory and enteric infections. Consistent and relentless messaging by global and local health authorities had resulted in heightened hygiene awareness amongst the public during the COVID-19 pandemic. Unfortunately, many of the hygiene behaviours practiced during the pandemic have proven to be unsustainable in the immediate period following the pandemic. While CDC guidelines suggest washing hands with soap for a minimum of 20 seconds to prevent the spread of germs, a hygiene interventions effectiveness must be evaluated in context of the prevalent hygiene behaviour. Here we report our findings from an observational study conducted across India, Pakistan, Saudi Arabia, and United Arab Emirates focusing on handwashing habit of individuals in the post-pandemic period. Across all geographies, the time spent for lathering product on skin (contact time) for a significant majority of individuals recruited for the study was found to be 10 seconds and less. To ensure that marketed hygiene formulations such as liquid cleansers and sanitizers are efficacious in inactivating pathogens under conditions practiced by the majority as a part of their daily hand washing practices, we have investigated the in-vitro antimicrobial efficacy of several hygiene cleansing formulations at 10 seconds of contact time. Our results show that well-formulated cleansing solutions can reduce the input titre of both bacterial and viral pathogens by 99.9% or more, even with brief contact. With the global resurgence of both existing and emerging pathogens in the post-pandemic world, promoting sustainable handwashing practices for infection prevention remains a challenge as it is deeply rooted in the socio-economic fabric of many countries. Therefore, it is crucial to conduct regular studies like this to reassure end-users and combat complacency regarding the composition of everyday hygiene products. HighlightsO_LIStudies of handwashing behavior in 4 countries reveals significantly short lathering duration C_LIO_LIAntimicrobial efficacy testing of marketed products was conducted against a range of pathogens C_LIO_LISuitably formulated hygiene products can inactivate pathogens at short durations of contact C_LI

microbiology↗

Chemical inactivation of two non-enveloped viruses follows distinct molecular pathways

Non-enveloped viruses, which lack a lipid envelope, typically display higher resistance to disinfectants, soaps and sanitizers compared to enveloped viruses. The capsids of these viruses are highly stable and symmetric protein shells that resist inactivation by commonly employed virucidal agents. This group of viruses include highly transmissible human pathogens such as Rotavirus, Poliovirus, Foot and Mouth Disease Virus, Norovirus and Adenovirus; thus, devising appropriate strategies for chemical disinfection is essential. We tested a mild combination of a denaturant, alcohol, and organic acid on two representative non-enveloped viruses - Human Adenovirus 5 (HAdV5) and Feline Calicivirus (FCV)- and evaluated the molecular pathway of capsid neutralization using biophysical methods. The transition temperatures signifying conformational shifts in the capsid were established in the presence and absence of chemical treatment using Differential Scanning Calorimetry (DSC), while the corresponding morphological alterations were visualized and correlated using Transmission Electron Microscopy (TEM). We found that while chemical treatment of purified HAdV5 particles resulted in increased thermal instability, followed by large scale particle aggregation; similar treatment of FCV particles resulted in complete collapse of the capsids. The distinct effects of the chemical treatment on the morphology of HAdV5 and FCV suggests that non-enveloped viruses with icosahedral geometry can follow different molecular pathways to inactivation. Further, while individual components of the chemical formulation caused significant damage to the capsids, a synergistic action of the whole formulation was evident against both non-enveloped viruses tested. Molecular level understanding of inactivation pathways may result in the design and development of effective mass-market formulations for rapid neutralization of non-enveloped viruses. HighlightsO_LIformulation consisting of 3.2% citric acid, 1% urea in 70% ethanol, pH4 effectively inactivates HAdV5 and FCV. C_LIO_LIinactivation pathways with complete formulation, are different for the two viruses. C_LIO_LIeffect of whole formulation is more effective compared to individual components. C_LI

microbiology↗