Potential Risk Of Viral Transmission Research Articles

In-depth Characterization of Vaccine Breakthrough Infections With SARS-CoV-2 Among Health Care Workers in a Dutch Academic Medical Center.

Severe acute respiratory syndrome coronavirus 2 infection after coronavirus disease 2019 vaccination raises concerns about the emergence of vaccine escape variants. Here we characterize 14 breakthrough infections among 5860 fully vaccinated Dutch health care workers ≥14 days after the final dose of vaccination with either BNT162b2, mRNA-1273, or Ad26.COV2.S. These breakthrough infections presented with regular B.1.1.7 (Alpha) and B.1.617.2 (Delta) variants and high viral loads, despite normal vaccine-induced B- and T-cell immune responses detected by live virus neutralization assays and ELISpot. High-risk exposure settings, such as in households, indicate a potential risk of viral transmission despite full vaccination.

Persistence of SARS-CoV-2 RNA in the nasopharyngeal, blood, urine, and stool samples of patients with COVID-19: a hospital-based longitudinal study

BackgroundThe persistence of severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) RNA in the body fluids of patients with the novel coronavirus disease 2019 (COVID-19) may increase the potential risk of viral transmission. There is still uncertainty on whether the recommended quarantine duration is sufficient to reduce the risk of transmission. This study aimed to investigate the persistence of SARS-CoV-2 RNA in the nasopharyngeal, blood, urine, and stool samples of patients with COVID-19.MethodsIn this hospital-based longitudinal study, 100 confirmed cases of COVID-19 were recruited between March 2020 and August 2020 in Guilan Province, north of Iran. Nasopharyngeal, blood, urine, and stool samples were obtained from each participant at the time of hospital admission, upon discharge, 1 week after discharge, and every 2 weeks until all samples were negative for SARS-CoV-2 RNA by reverse transcription-polymerase chain reaction (RT-PCR) assay. A survival analysis was also performed to identify the duration of viral persistence.ResultsThe median duration of viral RNA persistence in the nasopharyngeal samples was 8 days from the first positive RT-PCR result upon admission (95% CI 6.91–9.09); the maximum duration of viral shedding was 25 days from admission. Positive blood, urine, and stool RT-PCR results were detected in 24%, 7%, and 6% of the patients, respectively. The median duration of viral persistence in the blood, urine, and stool samples was 7 days (95% CI 6.07–7.93), 6 days (95% CI 4.16–8.41), and 13 days (95% CI 6.96–19.4), respectively. Also, the maximum duration of viral persistence in the blood, urine, and stool samples was 17, 11, and 42 days from admission, respectively.ConclusionAccording to the present results, immediately after the hospitalized patients were discharged, no evidence of viral genetic materials was found. Therefore, appropriate treatments were selected for the patients at this hospital. However, we recommend further investigations on a larger sample size in multi-center and prospective randomized controlled trials (RCTs) to evaluate the effects of different drugs on the shedding of the virus through body secretions.

Laparoscopic surgery during the COVID-19 pandemic: detection of SARS-COV-2 in abdominal tissues, fluids, and surgical smoke.

BackgroundThere are still concerns over the safety of laparoscopic surgery in coronavirus disease 2019 (COVID-19) patients due to the potential risk of viral transmission through surgical smoke/laparoscopic pneumoperitoneum.MethodsWe performed a systematic review of currently available literature to determine the presence of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) in abdominal tissues or fluids and in surgical smoke.ResultsA total of 19 studies (15 case reports and 4 case series) comprising 29 COVID-19 patients were included. The viral RNA was positively identified in 11 patients (37.9%). The samples that tested positive include the peritoneal fluid, bile, ascitic fluid, peritoneal dialysate, duodenal wall, and appendix. Similar samples, together with the omentum and abdominal subcutaneous fat, tested negative in the other patients. Only one study investigated SARS-COV-2 RNA in surgical smoke generated during laparoscopy, reporting negative findings.ConclusionsThere are conflicting results regarding the presence of SARS-COV-2 in abdominal tissues and fluids. No currently available evidence supports the hypothesis that SARS-COV-2 can be aerosolized and transmitted through surgical smoke. Larger studies are urgently needed to corroborate these findings.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00423-021-02142-8.

Oscillometry – The future of estimating pulmonary functions

The prevalence of asthma is increasing rapidly, worldwide, due to changing gene-environment interactions. The rate of rise is more in resource poor nations due to lack of knowledge and non-availability of expertise. Monitoring of lung functions is mandatory for diagnosis and further management of asthmatic patients. Spirometry, the widely available investigation, is the gold standard test used for mapping pulmonary dynamicity. It has got its own limitations in the form of operational difficulties in children, the elderly, and in those with neuromuscular or behavioral issues. In the current era of COVID-19 pandemic, the utility of spirometry has been further restricted to selected cohort only, due to potential risk of viral transmission during the procedure. Oscillometry technique has been used previously, to monitor lung functions, with promising results. Ultrasonic waves of various frequencies accompany the tidal breath of patients and respiratory impedance is calculated by measured pressure and flow signals from exhaled breath. The results are interpreted in the form of resistance, reactance, resonant frequency, and reactance area. Various manufacturers have developed different mechanical models with slight variation in impulse pattern till date. There are certain distinct advantages of oscillometry over spirometry. Being tidal breath-based maneuver, it is more child friendly. People with neuromuscular weakness, cognitive limitations, and the elderly can easily perform it with only minor understanding and effort. Oscillometry is more sensitive than spirometry in detecting peripheral airway diseases. Post-bronchodilator reversibility can be evaluated by comparing with the baseline respiratory characteristics. Their utility in restrictive diseases and vocal cord dysfunction has also been explored. Less aerosol generation during the normal tidal breath is another advantage of oscillometry, over spirometry needing forceful efforts, which makes it more suitable for use in viral pandemic situations for monitoring patients with both asthma and pneumonia. More research is needed, in various geographic locations and heterogeneous populations, to devise the normative data of oscillometric parameters. Simultaneously, there is an urgent need for standardization of available machines at global platform.

Presence of Ebola virus in breast milk and risk of mother-to-child transmission: synthesis of evidence.

To help inform global guidelines on infant feeding, this systematic review synthesizes evidence related to the presence of the Ebola virus (EBOV) in breast milk and its potential risk of viral transmission to the infant when breastfeeding. We relied on a comprehensive search strategy to identify studies including women with suspected, probable, or confirmed EBOV infection, intending to breastfeed or give breast milk to an infant. Our search identified 10,454 records, and after deduplication and screening, we assessed 148 full texts. We included eight studies reporting on 10 breastfeeding mothers and their children (one mother with twins), who provided breast milk samples for assessment. EBOV was detected via RT‐PCR or viral culture in seven out of ten breast milk samples. Four out of the five‐breastfed infants with EBOV‐positive breast milk were found positive for EBOV infection, and all of these EBOV‐positive infants died. Since previous reports have detected EBOV in tears, saliva, sweat, and contaminated surfaces, with the current evidence, it is not possible to conclude with certainty that breast milk was the main route of EBOV transmission.

Hepatitis E virus in Spanish donors and the necessity for screening.

Hepatitis E virus (HEV) represents a major health problem worldwide. As the course of HEV cases is often subclinical, asymptomatic infections could represent an important source of viral spread and infection via routes such as blood donations. Before universal screening for HEV in blood donations can be implemented, studies evaluating the incidence of infection are needed to establish the potential risk of viral transmission. This is a prospective longitudinal study that included blood donors recruited at the Hospital de Ciudad Real Transfusion Service between October 2017 and January 2018. Pools of eight donations were tested for HEV viremia by PCR. Positive pools were individually evaluated following the same procedure. Positive samples were tested for anti-HEV IgG and IgM. Recipients of blood transfusions obtained from HEV-positive donors were retrospectively evaluated. The prevalence of HEV was calculated. A total of 11313 healthy donors were analysed during the study period. Four blood donations from four different donors were HEV RNA-reactive. The prevalence of HEV infection was 0.035% (95% CI: 0.01%-0.09%), which meant a ratio of one positive donation per 2828 donations. All donors were negative for anti-HEV IgM at the time of the donation. Five patients received transfusions from HEV-positive blood donations, none of them showed an increase in alanine aminotransferase levels after transfusion. In conclusion, our study found a high prevalence of HEV infection in blood donors from south-central Spain. In view of the prevalence, Spanish blood banks should carefully consider including screening for HEV.

Potential risk of viral transmission from flying foxes to domestic animals and humans on the southern coast of West Java, Indonesia.

Flying foxes have been considered to be involved in the transmission of serious infectious diseases to humans. Using questionnaires, we aimed to determine the direct and/or indirect contacts of flying foxes in an Indonesian nature conservation area with domestic animals and humans living in the surrounding area. We surveyed 150 residents of 10 villages in West Java. Villages were classified into 3 groups: inside and/or within 1 km from the outer border of the conservation area and 1–5 km or 5–10 km away from the reserve’s outer border. Data were collected by direct interview using a structured questionnaire consisting of the respondent characteristics (age, sex and occupation); histories of contacts between flying foxes and humans, dogs and other domestic animals; and knowledge about infectious diseases, mainly rabies, in flying foxes. We found that flying foxes from the nature conservation area often enter residential areas at night to look for food, especially during the fruit season. In these residential areas, flying foxes had direct contacts with humans and a few contacts with domestic animals, especially dogs. People who encounter flying foxes seldom used personal protective equipment, such as leather gloves, goggles and caps. The residents living around the conservation area mostly had poor knowledge about flying foxes and disease transmission. This situation shows that the population in this region is at a quite high risk for contracting infectious diseases from flying foxes.

Cryoprecipitate: no longer the best therapeutic choice in congenital fibrinogen disorders?

Congenital abnormalities of fibrinogen are rare disorders classified as quantitative (afibrinogenemia and hypofibrinogenemia) or qualitative types (dysfibrinogenemia and hypodysfibrinogenemia). Fibrinogen is essential to haemostasis as the substrate for fibrin clot formation and also acts in primary haemostasis as a key ligand in platelet aggregation. Quantitative deficiency of fibrinogen can result in severe bleeding, or arterial and venous thromboembolism, and poor wound healing. Dysfibrinogenemia is characterized by functional abnormalities of fibrinogen, which may be asymptomatic (in 50% of cases), or cause bleeding (25%) or thrombosis (25%). Replacement of the deficient or abnormal fibrinogen with frozen plasma, cryoprecipitate, or fibrinogen concentrate has been found to be effective in practice in treating haemostatic complications of these disorders. Although cryoprecipitate is the most commonly used replacement material, pathogen-reduced fibrinogen concentrates have several advantages, most importantly a lower potential risk of viral transmission and standardized fibrinogen content allowing accurate dosing. They also avoid transfusing unwanted clotting factors, platelet microparticles and immunoglobulins, and can be administered rapidly without thawing. The use of fibrinogen concentrate to treat congenital fibrinogen disorders is strongly supported in principle and increasingly by practical experience and evidence.

Pharmacokinetics, Clinical Efficacy and Safety of Plasma-Derived Nanofiltered C1 Inhibitor Concentrate for Treatment of Hereditary and Acquired Angioedema.

RATIONALE: From the early 70's, C1 inhibitor concentrate manufactured from pooled human plasma has been available to patients with hereditary and acquired angioedema (HAE and AAE) and in 1997 a highly purified C1 inhibitor (Cetor®) was introduced. Many precautions have been taken to minimize the potential risk of viral transmission (e.g. rigorously controlled whole blood collection systems, extensive screening of each individual donation for a variety of blood-borne viruses, pasteurisation). To further minimize the potential risk of viral transmission, a 15 nm filtration was implemented in the manufacturing process giving rise to C1-inhibitor-N (anofiltered).DESIGN: A randomised, double-blind, controlled cross-over phase II study was conducted in which our primary objective was to compare the pharmacokinetics of the newly developed concentrate with conventional C1-inhibitor concentrate in HAE patients without signs of an attack of angioedema. Secondly, an open-label phase III study in patients with an HAE attack was performed to investigate whether the introduction of the virus reducing 15nm filtration step in the manufacturing process of the concentrate did not affect the efficacy and safety of the product.RESULTS: Thirteen patients were enrolled in the phase II study. No differences between conventional C1-inhibitor concentrate and nanofiltered C1-inhibitor concentrate were detected with regard to the primary pharmacokinetic parameters clearance, volume of distribution, and the fraction of C1-inhibitor-N detected by the antigen assay relative to the functional assay. Therefore incremental recovery, mean residence time, half-life and the area under curve were equivalent for both products. In the phase III study, 8 HAE patients were enrolled. In these 8 patients, 14 attacks qualified as acute angioedema attack. The mean time-to-relief for attacks treated with new C1-inhibitor concentrate was 3.0 (SD 2.5) hours. Historical data showed that treatment with conventional C1-inhibitor concentrate resulted in time-to-relief of 3.9 (SD 6.2) hours, whereas for untreated attacks this was 24.7 (SD 19.9) hours. The attacks treated with new C1-esterase inhibitor concentrate had a mean time-to-resolve of 18.6 hours (SD 13.1) whereas medical history showed an time-to-resolve of 17.8 hours (SD 17.2) for conventional C1-inhibitor. Untreated attacks showed a mean time-to-resolve of 63.6 hours (SD 31.0).CONCLUSION: The newly developed nanofiltered C1-esterase inhibitor has equal pharmacokinetic properties compared to the conventional concentrate. The viral reduction step (15 nm filtration) in the production process of Cetor did not induce changes in the efficacy and safety in the treatment of acute angioedema attacks and in the pharmacokinetic parameters.

Hepatitis C and Ocular Surface Disease

To assess the frequency of changes in the ocular surface and the presence of hepatitis C virus (HCV) in tear samples of patients with chronic HCV infection. Prospective, nonrandomized, clinical, interdisciplinary, single-center study. Seventy-one patients with previously untreated chronic HCV infection and a control group consisting of 66 patients without systemic HCV infection were enrolled in the trial. The patients with HCV infection were screened for ocular symptoms, visual acuity, and ocular changes. Tear production was measured by the Jones test. Conjunctival impression cytologic analysis was performed. The presence of HCV ribonucleic acid (RNA) in tear and blood samples was determined by quantitative polymerase chain reaction. On examination, systemic HCV infection was present for a median of 30 months. Fifty percent of all HCV patients showed a decrease in tear production measured by the Jones test. Apart from epithelial changes related to dry eye syndrome in 12 patients, two patients presented mild peripheral corneal thinning. Polymerase chain reaction analysis detected HCV RNA in five (10%) of 52 tear samples. HCV RNA levels in tear samples (mean, 1.0 x 10(4) copies/ml) were considerably lower than in blood samples (mean, 5.3 x 10(5) copies/ml). Dry eye syndrome is the most frequently observed ocular feature in HCV infection. Patients with HCV infection (age range, 21 to 60 years) compared with the controls had a significant lower tear production (P = .05). The presence of HCV RNA in 10% of tear samples emphasizes the potential risk of viral transmission through tears.

Prevention of hepatitis B virus transmission from an infected stem cell donor

The decision to accept a sibling with active hepatitis B virus (HBV) replication for hematopoietic stem cell (HSC) donation is controversial owing to the potential risk of viral transmission to the recipient and subsequent development of hepatitis B, which might be fatal.1, 2, 3 Here, we report a successful strategy to prevent transmission from a viremic donor to an HBV-naive recipient.

Ultrastructural alterations in human blood leukocytes induced by porcine circovirus type 1 infection

Swine infectious pathogens, especially viruses, represent a potential public health risk associated with the use of pig tissues for xenotransplantation in humans. We hypothesized that porcine circovirus type I (PCV-1) may infect human mononuclear cells, resulting in ultrastructural alterations of the target cells. Transmission electron microscopy was used for evaluating ultrastructural alterations of human cells exposed to a PCV-infected PK15 cell line. A polymerase chain reaction (PCR) assay and fluorescence in situ hybridization (FISH) were developed for detecting PCV-1 in human mononuclear cells. Morphological alterations of the human T cells exposed to PCV PK15 showed ''boomerang-shaped'' intracytoplasmic inclusions. Nucleocapsids appeared free, close to the nucleus, or contained into cytoplasmic vacuoles. Virions were observed near the surface of the human cells. A considerable number of mature virions and immature forms could be observed in the human cells that had a completely intact nuclear membrane with no alteration in the disposition of chromatin. PCV-1 particles were identified budding into typical Golgi saccules and vacuoles. Virions sized up to 23 nm in diameter, and appeared in the nucleus and in the periphery of the cellular core. PCV-1 infection was detected on CD4+, CD8+, CD14+, CD19+, and CD56+ human cells by PCR assay and FISH. These results suggest that PCV has the capability of infecting human leukocytes in vitro, and should be considered a potential risk of viral transmission during xenotransplantation.

Fibrin sealants in surgical practice: An overview

The need to effectively manage hemostasis and tissue sealing during surgery has had a strong influence on the development of modern surgical techniques. A group of agents known as surgical tissue adhesives has been developed to promote hemostasis and tissue sealing during surgery, and these comprise both natural and synthetic agents. Fibrin sealants are the most effective tissue adhesives currently available, and they are biocompatible and biodegradable. The fibrin sealants are comprised of purified, virus-inactivated human fibrinogen, human thrombin, and sometimes added components, such as virus-inactivated human factor XIII and bovine aprotinin. These agents mimic the final steps of the physiological coagulation cascade to form a fibrin clot. The use of any plasma-derived product in the surgical setting carries a potential risk of viral transmission. In fact, it was the risk of viral transmission from fibrinogen and thrombin that halted development work on fibrin sealants in the United States. Since that time, new techniques for isolating and concentrating plasma fractions have been developed, and national and international guidelines have been introduced to ensure the safety of all plasma products. All plasma donors are carefully selected and their plasma units screened for viral contamination before processing. All plasma donations and bovine tissue used in the production of commercial fibrin sealants undergo rigorous viral reduction/elimination steps. As a result of this carefully controlled and monitored process, there have been no proven cases of viral transmission associated with the use of commercial fibrin sealant. Fibrin sealants are currently used in a number of surgical specialties, including cardiovascular surgery, thoracic surgery, neurosurgery, plastic and reconstructive surgery, and dental surgery. The use of fibrin sealants has a positive effect on surgical outcomes, such as improved time to hemostasis, reduced blood loss, and reduced complications. This review describes the development of fibrin sealants, the composition of currently available products, and their use in surgical practice.

Productive infection of primary human endothelial cells by pig endogenous retrovirus (PERV).

The potential risk of viral transmission in the setting of xenotransplantation has gained major attention. Different porcine cell types have been shown to release retroviral particles, which are infectious for human cell lines in vitro. However, there are only a few data on whether PERV (pig endogenous retrovirus) is able to infect primary human cells. In this study we have analyzed endothelial cells, vascular fibroblasts, mesangial cells, mononuclear cells, hematopoetic stem cells and bone marrow stromal cells for PERV transmission. We now provide evidence for primary human endothelial cells, vascular fibroblasts, and mesangial cells to be susceptible to PERV transmission. PERV infection was productive in endothelial cells and mesangial cells. Our data confirm and extend former reports concerning the PERV infection of human cells. The PERV infection of different primary human cells represents further significant evidence for a viral risk during xenotransplantation. In this context, special attention should be directed towards productive infection of human endothelial cells: in the setting of xenotransplantation this cell type will have close contact with porcine cells and PERV particles.

Novel Uses of Fibrin Glue in Vascular Surgery

The field of tissue adhesives has recently developed a number of novel clinical applications especially relevant to the surgical specialties. Fibrin glue has been commonly used as a hemostatic agent. In this article, we discuss the most common use of fibrin glue as an adjunct to control hemorrhage, as well as its use as a means to deliver biologic substances to a target. We then will describe some novel applications of fibrin glue in various specialties. Future applications of biologic tissue adhesives will depend on our ability to develop a product that will provide all the benefits discussed without incurring the potential risk of viral transmission.

Evolution of infectious disease: A biocultural analysis of AIDS.

The evolution of infectious disease can be understood from an ecological model that incorporates information from anthropology, epidemiology, and biomedicine. This model considers variables such as the pathogen, the host population, and the environment. In this model, the role that culture as well as other environmental variables plays in the transmission of infectious disease in human populations is considered. In addition, the sociocultural response and its impact on the disease process can be analyzed. The present AIDS epidemic is placed in an ecological and evolutionary context of the disease in hominid evolution. The interaction between Human Immunodeficiency Virus (HIV) and human populations is considered in this perspective. The ability of the virus to survive in semen and blood both increases as well as limits the possibility of transmission. Cultural practices that increase the transmission of blood and semen or increase sexual activity will obviously increase the potential risk of viral transmission. In societies that practice exchange of blood, blood transfusion, and where vaccinations with unclean needles exist or where there is intravenous (IV) drug use, the transmission of HIV by blood is enhanced. HIV which can cause a breakdown of the immunological system is paradoxically a very fragile pathogen. Replication occurs within T-cells, an important part of the immunological system. Outside of the blood or semen the virus dies quickly. From the perspective of the pathogen's adaptation, the virus has effectively solved the problem of survival. The fragile virus's long incubation period and its ability to survive in the presence of antibodies help to assure its transmission. HIV's ability to suppress the immunological system may assure its immediate survival, but this adaptation may cause the death of its host from other opportunistic pathogens that are usually not lethal.