DNA extraction of bacterial cells using a semi-automated filtration system.

The COVID-19 pandemic lockdown created problems with importing of commercial kits resulting in extended turnaround times for consumable deliveries. One way to circumvent this was to use an inexpensive optimized in-house method for DNA extraction from water. • The DNA extraction methods were optimized on a 96-well plate using a semi-automated filtration system to increase the number of samples from 24 to 96 at a time in 2 h. The DNA extraction method optimizations included: (a) Guanidium thiocyanate method plus dilution series of celite to determine DNA binding capacity; (b) QIamp 96 Qiacube HT kit (Qiagen®); (c) Guanidium thiocyanate with the celite replaced with a binding buffer. • The in-house DNA extraction methods and adapted in-house DNA extraction method were compared to QIamp 96 Qiacube HT kit (Qiagen®), which is used on a 96-well semi-automated filtration system. The results showed maximum capacity of the 96-well filter plates was 400 µâ„“ broth (OD600 = 0.45 = 3.6 × 108 cells/mℓ) before the 96-well filters blocked. • When the methods were compared, there was no significant difference between the in-house DNA extraction method with 1:420 celite dilution (P-value = 0.126) and the adapted in-house method with binding buffer (P-value = 0.298) DNA yield or amplification of PCR products.

A scoping review to identify the type and effect of hand hygiene interventions on the reduction of infectious diseases (including COVID-19) in preschool children

Background. Proper handwashing can reduce the burden of diseases related to hand hygiene (HH) and so contribute reducing under-5 mortality. Preschoolers can benefit from HH interventions by the burden of disease and absenteeism being reduced. Objective. To perform a scoping review of literature to assess the types and effectiveness of HH interventions at preschools, with a view to providing a guideline for appropriate interventions for South African facilities. Methods. A literature search was conducted through the PubMed database to identify relevant studies. An iterative screening process to focus the review allowed for information on the type and effectiveness of interventions to be collated. An updated PubMed search was conducted to determine whether any interventions related to COVID-19 at preschools could be included. Results. No additional studies relating to COVID-19 were found. Of the 305 studies identified during the initial search, only 12 fitted the specific search criteria. Of these, 10 studies showed improvements in HH-related indicators following the interventions. Only two studies used health education as an intervention, whereas the others included the supply of HH products (to varying extents) as part of the intervention. Conclusion. HH interventions appear successful in reducing diseases spread by poor HH, improving general HH practices and reducing absenteeism among preschoolers. Studies using innovative, entertaining methods of educating children have shown to be successful in improving handwashing techniques and decreasing microbial growth on children’s hands. HH interventions are suggested as an effective measure to improve HH during the COVID-19 pandemic.