No abstract

The purpose of this study was to evaluate persistent activity of three alcohol-based antiseptics widely used in the clinical routine containing chlorhexidine, triclosan or mecetronium after hand disinfection. Four tests were used to evaluate the antimicrobial activity of antiseptics on: (i) resident microbiota; (ii) nutrient agar plates (NAP) subsequently inoculated with a test organism; and transient microbiota acquired by contact with dry hands (iii), or (iv) a wet inert surface that had been artificially contaminated. Four reference strains (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis) and an Acinetobacter baumannii strain responsible for a hospital outbreak were used as transient microbiota. Antimicrobial activity was calculated according to the CFUs reduction by reference to non-disinfected control hands. The antiseptics were applied according to European Standard EN1500. Solutions containing chlorhexidine or triclosan showed some persistent effects on transient microbiota on inert humid surfaces and NAP, but not on contaminated dry hands. Solutions containing mecetronium showed no persistent effect on transient flora in any of the trials. All alcohol-based antiseptics tested were more effective against resident flora than soap. No persistent activity was observed for A. baumannii in any of the trials. Chlorhexidine and triclosan are preferred when an antiseptic with persistent activity is desired, but a moist environment appears to be necessary for that antibacterial activity. Accordingly, relevant conclusions regarding the persistent activity of antiseptics for clinical practice and protection against bacterial contamination cannot be derived from this study for the alcoholic solutions tested.

The success of Acinetobacter baumannii as an emerging organism is probably linked to its high resistance to adverse environmental conditions. This study was conducted to analyze the association between some factors that may favor the dissemination of A. baumannii clinical isolates. A total of 47 clinical strains of A. baumannii were evaluated to carbapenem, the ability to produce biofilm, the susceptibility to some antiseptics, and the survival time on cotton fabrics. Most of the isolates were resistant to carbapenem (72.3%), produced biofilm (83%), and survived more than 7 (51%) days on fabrics. A significant association between decreased susceptibility to antiseptics containing chlorhexidine or triclosan and carbapenem resistance and survival on fabrics could be observed. The resistance to carbapenem was significantly associated with survival on fabric, but not with the ability to form biofilm. The survival of the isolates on fabric was not associated with the ability to produce biofilms. Characteristics, such as resistance to antibiotics, ability to form biofilm, and survival on dry surfaces, probably contribute to the proliferation of this organism when selected in the hospital environment and can partly explain its success as responsible for nosocomial infection.

Crises and disasters affect the numbers of people traveling either for tourism or other reasons. Many studies have been published on the effects of such events on travel, especially on tourism, and based on the arrivals or departures of travelers to or from countries. Our aim was to assess the influence of these events on the demand for pre-travel medical consultation in an International Vaccination Centre (IVC). Data on 94683 international travelers who visited 113529 international destinations attended at the IVC of Malaga (Spain) during 2000–2017 were studied. A descriptive and time series analyses was conducted. The demand to IVC was 3.47 times higher in 2017 than in 2000. The increase has not been the same for all destinations: Travel to South-East Asia and Western Pacific World Health Organization (WHO) regions has multiplied by 10, while in the same period, Africa WHO region has declined from 36% to 20% of total demand. Thailand, India and Brazil were the countries with the highest demand (21% of all pre-travel consultations). We found out three periods, concurrent with some socioeconomic or health events, in which the number of travellers attend decline with respect to the previous years, or the growth was very slow. Growth in the demand for pre-travel medical advice in parallel with a foreseeable increase in the number of travelers is expected. Pre-travel medical services must be adapted to this increase. This study of the trend of demand for pre-travel medical information should new related problems to travel to be identified and quantified, and should assist improvement of policies and programs aimed at care of travelers.

Travelers with preexisting diseases or chronic conditions may be more susceptible to travel-related health risks. They may, therefore, require more attention from specialist travel medicine providers. Our objective was to examine a group of international travelers in Malaga, Spain, quantify the proportion of travelers suffering from chronic conditions, and understand the characteristics of this group. A representative sample of travelers requesting pretravel medical advice at one travel clinic were asked about their preexisting chronic conditions and any immunosuppression. Additional demographic variables were used in an analysis of bivariate correlations. We used a binary logistic regression analysis to identify relationships between independent variables (age, gender, type of trip, travel duration, and destination) and the presence or absence of chronic conditions in travelers. Of the sample of 1,196 travelers, 258 (21.6%) reported having preexisting chronic conditions and 72 (6%) had two or more chronic conditions. Twenty-four of the travelers with chronic conditions (9%) were immunocompromised because of the disease or treatment. The two most common chronic conditions were cardiovascular disease and chronic respiratory conditions (36.8% and 17.1%, respectively). The chronic condition increased by 6.7% for every year of increased age. Travelers with chronic conditions are older, travel mainly to visit friends and relatives, and take shorter trips. More than half of travelers visiting (55.8%) needed more attention from the travel medicine practitioner because of their preexisting chronic conditions, age, or type of travel. Surveillance data based on the population of people traveling would be helpful to provide better advice to travelers.

We developed a fluorescent ␤-D-glucuronidase activity (BGA)-based assay for detecting and quantifying Escherichia coli in samples to assess the biocide efficacy of hand antiseptics. The fluorescence level is proportional to the number of viable E. coli organisms present. We compared our assay results to those of the E. coli plate count method specified by the European standard for testing hygienic hand rub disinfectant products (EN1500). The plate count method requires excessive handling and materials and is not valid if the number of organisms per plate is too low or high for counting in many of the samples. We optimized the fluorescent assay based on the cleavage of 4-methylumbelliferyl-␤-D-glucuronide by adding 4-nitrophenyl-␤-D-glucuronide, a nonfluorogenic BGA substrate, to induce glucuronidase activity and reduce assay time. Furthermore, our method can be automated and eliminates the need for multiple dilutions. Fluorescence was temporally monitored, and the time required to reach a specific value of fluorescence was correlated with the initial number of viable E. coli organisms on the samples. There was a positive correlation (P < 0.05) with a high correlation coefficient (R 2 ‫؍‬ 0.82) between the E. coli counts by plate count and fluorescence methods. Reported effects in fluorescent BGA were compared to the EN1500 plate count method with five hand disinfectants. We found our method more advantageous, because it was as sensitive as the EN1500 method, requires less time to complete, and is less expensive and less laborious than conventional plating techniques.

The spread of coronavirus disease 2019 (COVID-19) has promoted the use of hand sanitizers among the general population as recommended by health authorities. Alcohols, which are used in many hand sanitizers, have been shown to promotes the formation of biofilms by certain bacteria and to increase bacterial resistance to disinfection. We investigated the effect of continued use of alcohol-based gel hand sanitizer on biofilm formation by the Staphylococcus epidermidis resident strain isolated from the hands of health science students. Hand microbes were counted before and after handwashing, and the ability to produce biofilms was investigated. We found that 179 (84.8%) strains of S. epidermidis isolated from hands had the ability to form biofilm (biofilm-positive strains) in an alcohol-free culture medium. Furthermore, the presence of alcohol in the culture medium induced biofilm formation in 13 (40.6%) of the biofilm-negative strains and increased biofilm production in 111 (76.6%) strains, which were classified as low-grade biofilm-producing. Based on our findings, there is no clear evidence that the continued use of alcohol-based gels results in the selection of strains with the capacity to form biofilms. However, other disinfectant formulations that are more commonly used in clinical settings, such as alcohol-based hand-rub solutions, should be tested for their long-term effects.