Visualization of Airborne Particles as a Risk for Microbial Contamination in Orthopedic Surgery

Background: The operating theater is recognized to involve a high frequency of occupational blood and body fluid contacts.Objectives: This study aimed to visualize the production of blood and body fluid airborne particles by surgical procedures and to investigate risks of microbial contamination of the conjunctival membranes of surgical staff during orthopedic operations.Methods: Two physicians simulated total knee arthroplasty (TKA) and total hip arthroplasty (THA) in a bio-clean theater using model bones. The generation and behaviors of airborne particles were filmed using a fine particle visualization system, and numbers of airborne particles per 2.83 L of air were counted at the height of the operating and instrument tables. Each action was repeated five times, and particle counts were evaluated statistically.Results: Numerous airborne particles were dispersed to higher and wider areas while “cutting bones in TKA” and “striking and driving the cup component on the pelvic bone in THA” compared to other surgical procedures. The highest particle counts were detected while “cutting bones in TKA” under unidirectional laminar air flow.Discussion: These results provide a clearer image of the dispersion and distribution of airborne particles and identified higher-risk surgical procedures for microbial contamination of the conjunctival membranes. Surgical staff including surgeons, nurses, anesthesiologists, and visitors, should pay attention to and take measures against occupational infection particularly in high-risk surgical situations.

Molecular biology as a diagnostic tool for detection of Leptospira spp. in cows of a border region – case report

The reproductive efficiency of livestock is the basis for the success of livestock, dairy or beef, and having high reproductive performance depends on several factors within the production system and the presence of infectious diseases of the reproductive sphere in the herd is one of the factors that can compromise that efficiency. The aim of this study was to use molecular biology as a diagnostic tool for the detection of Leptospira spp. DNA in cows with reproductive disorders on a rural property in the municipality of Boca do Acre, Amazonas, Brazil. Vaginal mucus was collected from nine Nelore breeding cows with a history of abortion and birth of weak calves submitted to DNA extraction and nested-PCR technique for 16S gene amplification at the bacterial genus level. Of the nine samples analyzed, five (55.55%) amplified a product of 331bp. The municipality of Boca do Acre is bordered by Peru and Bolivia, and knowledge of the prevalence of the disease, serovars, and circulating Leptospira species is essential for the adoption of measures related to animal husbandry, as well as health education for ranchers and their workers to avoid a possible occupational infection since this disease is considered an important zoonosis. New molecular studies using primers that allow the identification of the Leptospira species and mainly pathogenic species should be conducted in this region in order to elucidate the possible species of this etiological agent and the possible reservoirs of the disease to begin the understanding of the epidemiology of this disease in cattle in this region of border.

Incidence of COVID-19 in outpatient healthcare workers

Currently, work in any medical organization carries a risk of coronavirus infection, and, first of all, this applies to medical organizations dealing with the treatment of patients infected with coronavirus. Medical workers are a group at increased risk of infection with the SARS-CoV-2 virus in the provision of medical care in modern conditions, which determines their incidence of COVID-19 [1-3]. The aim of the study is to explore the prevalence of cases of COVID-19 infection in medical workers providing medical care on an outpatient basis. Materials and methods. The analysis of the incidence of COVID-19 medical workers in one of the large medical organizations of the Samara region during the period of the pandemic was carried out. The medical staff of the medical organization includes 207 doctors. There are 11 subdivisions in the structure of the medical and prophylactic institution. Research methods: content analysis of the modern regulatory framework (2020-2021), statistical, expert. For the period from May 2020 to March 2021 71 cases of infection of medical workers on an outpatient basis with SARS-CoV-2 were identified, of which 32 doctors (45%) and 39 people (55%) nurses. Based on the results of the expert assessment, the insurance nature of the infection case was established in 50 people (70%). Among the medical and nursing categories of medical workers, the largest number of cases was made by doctors and nurses of primary contact - specialists of the district service: general practitioners (40%), pediatricians (32%), doctors - obstetricians-gynecologists (12%), nurses adults (76%) and children (20%) polyclinic departments. A third of health workers received inpatient treatment for severe COVID-19, an average of 60 days. Conclusion. Medical workers are a risk group of COVID-19 who need support measures, since the possibility of occupational infection has been sufficiently proven, and the risk probably depends on the work performed and the conditions of direct contact of medical personnel, which requires further study in the current persisting epidemic conditions.

Infection control, occupational and public health measures including mRNA-based vaccination against SARS-CoV-2 infections to protect healthcare workers from variants of concern: A 14-month observational study using surveillance data

Background We evaluated measures to protect healthcare workers (HCWs) in Vancouver, Canada, where variants of concern (VOC) went from <1% VOC in February 2021 to >92% in mid-May. Canada has amongst the longest periods between vaccine doses worldwide, despite Vancouver having the highest P.1 variant rate outside Brazil. Methods With surveillance data since the pandemic began, we tracked laboratory-confirmed SARS-CoV-2 infections, positivity rates, and vaccine uptake in all 25,558 HCWs in Vancouver Coastal Health, by occupation and subsector, and compared to the general population. Cox regression modelling adjusted for age and calendar-time calculated vaccine effectiveness (VE) against SARS-CoV-2 in fully vaccinated (≥ 7 days post-second dose), partially vaccinated infection (after 14 days) and unvaccinated HCWs; we also compared with unvaccinated community members of the same age-range. Findings Only 3.3% of our HCWs became infected, mirroring community rates, with peak positivity of 9.1%, compared to 11.8% in the community. As vaccine coverage increased, SARS-CoV-2 infections declined significantly in HCWs, despite a surge with predominantly VOC; unvaccinated HCWs had an infection rate of 1.3/10,000 person-days compared to 0.89 for HCWs post first dose, and 0.30 for fully vaccinated HCWs. VE compared to unvaccinated HCWs was 37.2% (95% CI: 16.6–52.7%) 14 days post-first dose, 79.2% (CI: 64.6–87.8%) 7 days post-second dose; one dose provided significant protection against infection until at least day 42. Compared with community infection rates, VE after one dose was 54.7% (CI: 44.8–62.9%); and 84.8% (CI: 75.2–90.7%) when fully vaccinated. Interpretation Rigorous droplet-contact precautions with N95s for aerosol-generating procedures are effective in preventing occupational infection in HCWs, with one dose of mRNA vaccination further reducing infection risk despite VOC and transmissibility concerns. Delaying second doses to allow more widespread vaccination against severe disease, with strict public health, occupational health and infection control measures, has been effective in protecting the healthcare workforce.

Occupational infection to Brucella abortus B19 vaccine despite antimicrobial prophylaxis

The authors report the case of a veterinarian who acquired brucellosis infection by accidental exposure to Brucella abortus vaccine (BRUCEL-VET B19) while performing animal vaccination. Antibiotic prophylaxis with doxycycline and rifampin for six weeks was indicated, but rifampin was discontinued after 10 days due to gastrointestinal intolerance. Despite prophylaxis, the patient seroconverted after 30 days, but was asymptomatic and did not require additional antibiotic therapy. Post-exposure prophylaxis of Brucella is not free from side effects and asymptomatic seroconversion can occur despite prophylaxis.

The Epidemiology of Sharp Injuries in Healthcare Workers at a Trinidadian Community Hospital

OBJECTIVE To describe the epidemiology of sharp injuries, in healthcare workers, at the Sangre Grande Hospital (SGH) in Trinidad. A secondary analysis of non-sharp injuries was also done. Sharp injuries predispose staff to blood borne infections and thus are occupational infection prevention and control matters. Sharp injuries were observed to be a problem at the SGH. This study served to gather data for informed decision making. METHODOLOGY A retrospective descriptive study was done by reviewing all IPC reporting forms from reported healthcare worker injuries at the Infection Prevention and Control (IPC) Department for the period 2007-2017. All persons recorded as having being injured by sharps and secondarily, non-sharp occupational exposures, at the IPC department were included. We looked at employee case management including testing for blood borne Human Immunodeficiency Virus (HIV), Hepatitis B Virus (HBV) and C virus (HCV), management and treatment. Simple descriptive statistics were used to present the findings. RESULTS All 148 notes were reviewed after which entries having greater than 10 missing data points or fields were excluded from the study analysis, leaving 138 notes. Age ranges were between 20 – 62 years with the mean age of the affected population being 33 years. A total of 104 (75.4%) females were injured compared to 32 (23.2%) males. Persons injured were mainly from the wards (n=81, 58.5%): internal medicine (n=46, 33.3%) and general surgery (n=22, 15.9%). Accident & Emergency (A&E) accounted for 10.1% (n=14) of the cases. Registered nurses (n=37, 26.8%), physicians (n=22, 15.9%) and students (n=20, 14.5%) were the main categories of staff affected. The highest number of events occurred between 10:00-11:00 in the morning [am] (n=29, 20.6%). The majority of these incidents (n=123, 89.1%) were first reported to SGH A&E. Most injuries occurred while disposing of needles (n=17, 12.3%). It was noted that 73 (52.9%) of the documented cases occurred on fingers. HIV, HAV & HBV tests were done in 136 (98.6%) of the 138 staff members recorded. In 120 (87%) events the source patient was tested. A total of 114 (84.4%) persons had been vaccinated for HBV; 77 (58.8%) persons had post exposure prophylaxis (HIV) for one month. One (1.3%) person reported seroconversion after six months to positive HIV status. CONCLUSION Sharp injuries in employees were common in internal medicine and general surgery wards. These injuries were common in the late morning, on the fingers. Only one exposed employee seroconverted over the entire period.

The handling of SARS-CoV-2 associated deaths - infectivity of the body

The body of a deceased with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection is considered infectious. In this study, we present the results of infectivity testing of the body and testing of mortuary staff for SARS-CoV-2. We performed real-time quantitative polymerase chain reaction (RT-qPCR) for SARS-CoV-2 on 33 decedents with ante mortem confirmed SARS-CoV-2 infection. Swabs of the body surface from five different body regions and from the body bag or coffin were examined. A subset of the swabs was brought into cell culture. In addition, screening of 25 Institute of Legal Medicine (ILM) personnel for ongoing or past SARS-CoV-2 infection was performed at two different time points during the pandemic. Swabs from all locations of the body surface and the body environment were negative in cases of negative post mortem nasopharyngeal testing (n=9). When the post mortem nasopharyngeal swab tested positive (n=24), between 0 and 5 of the body surface swabs were also positive, primarily the perioral region. In six of the cases, the body bag also yielded a positive result. The longest postmortem interval with positive SARS-CoV-2 RT-qPCR at the body surface was nine days. In no case viable SARS-CoV-2 was found on the skin of the bodies or the body bags. One employee (autopsy technician) had possible occupational infection with SARS-CoV-2; all other employees were tested negative for SARS-CoV-2 RNA or antibody twice. Our data indicate that with adequate management of general safety precautions, transmission of SARS-CoV-2 through autopsies and handling of bodies is unlikely.