Abstract:

The threat posed by the blood-borne pathogens is disproportionately distributed in different healthcare facilities in Cameroon. Thus, there is a need for continuous surveillance of TTIs in the country. This study aimed to assess the screening procedure for blood transfusion and determine the trend in immunological markers of TTIs among blood donors at the Mamfe District Hospital (MDH). A prospective descriptive and cross-sectional study was conducted at Mamfe District Hospital in 2022. A total of 165 blood donors were recruited and screened using both Rapid diagnostic tests and indirect ELISA for the detection of TTIs. Data generated was entered into an Excel spreadsheet and analysed using the statistical software R, version 4.2.0. Student t-test was used to compare both diagnostic techniques, and was considered significant when p < 0.05. The majority (75.20%) of the donors were of the O-positive blood type, repeat donors (69.10%) and were mainly family replacement and paid donors as against the voluntary blood donors (39.40% and 37.00% vs. 23.60% respectively). overall TTIs prevalence was 18.78% (31/165), with HBsAg being the most predominant marker (12.12%) followed by Treponema pallidum, HCV and HIV antibodies at 4.85% 1.21% and 0.60% respectively. Except for the HBV, The prevalence of TTIs was higher when using a single RDT than the ELISA test, and the difference was significant (p<0.05). Blood borne pathogens remain a major menace to safe blood transfusion practice in MDH. Therefore, the donor screening protocol in MDH should systematically incorporate a confirmation diagnostic test such as ELISA.

Abstarct:

Immortal time bias (ITB) is common in cohort studies and biases the association estimates between the treated and untreated individuals. We used data from an Italian study on COVID-19 vaccine effectiveness, with a large cohort, long follow-up, and adjustment for confounding factors, but affected by ITB. We verified the real impact of the vaccination campaign, comparing the risk of all-cause death between the vaccinated and the unvaccinated population.

We aligned all subjects on a single index date and considered the “all-cause deaths” outcome to compare the survival distributions of the unvaccinated group versus various vaccination statuses. The all-cause-death hazard ratios (HRs) in univariate analysis for vaccinated people with 1, 2, and 3/4 doses versus unvaccinated people were 0.88, 1.23, and 1.21, respectively. The multivariate values were 2.40, 1.98, and 0.99. Possible explanations of this trend of the HRs as vaccinations increase could be: a harvesting effect; a calendar-time bias, accounting for seasonality and pandemic waves; a case-counting window bias; a healthy-vaccinee bias; or some combination of these factors. With 2 and even with 3/4 doses, the calculated Restricted Mean Survival Time and Restricted Mean Time Lost showed a small but significant downside for the vaccinated populations.

The study results should lead to rethink political choices about pandemic management, supporting greater caution in the future.

Abstract:

Background: Many infections in healthcare facilities are associated with the microbiological quality of the work environment, generally due to poor sanitation. Aim: In order to evaluate the effectiveness of a decontamination protocol (cleaning + disinfection) applied at the “Université des Montagnes” Teaching Hospital, the present study assessed the variation of bacterial loads on surfaces subsequent to decontamination. The susceptibility of bacteria to disinfectants was also evaluated in the same frame. Methodology: This work was conducted with adjusted bacterial detection/enumeration and susceptibility test protocols and standard bacterial identification protocols. Sampling on surfaces was performed by wet swabbing before cleaning, between cleaning and disinfection, and after disinfection. Results: Major findings revealed the predominance of Staphylococcus on target surfaces (75.5%). High bacterial loads recorded on these surfaces before decontamination became undetectable after cleaning with the detergent “Pax Lemon”. The majority of isolates (98%) were susceptible to the disinfectants tested, (Surfanios^® 0.25% and sodium hypochlorite 0.12%). Conclusion: Overall, these findings indicated process effectiveness on the subjected bacterial populations and suggest the use of either Surfanios^® (0.25%) or sodium hypochlorite (0.12%) for work surface hygiene, justifying the use of these products in this department for surface decontamination. Also, cleaning with the detergent “Pax lemon” and disinfection with sodium hypochlorite may be sufficient for the types of surfaces subjected in the present research.