ABSTRACT
BACKGROUND: Under the pressure of non-pharmaceutical interventions (NPIs) targeting severe acute respiratory syndrome coronavirus 2, the prevalence of human adenovirus (HAdV) was monitored before and after NPIs launched on Jan 24, 2020 in pediatric patients in Beijing, China. METHODS: Respiratory samples collected from children hospitalized with acute respiratory infections from Jan 2015 to Dec 2021 were screened by direct immunofluorescence test or capillary electrophoresis-based multiplex PCR assay. The hexon, penton base, and fiber genes were amplified from HAdV positive specimens, then sequenced. For HAdV typing, phylogenetic trees were built by MEGA X. Then clinical data of HAdV positive cases were collected. All data were evaluated using SPSS Statistics 22.0 software. RESULTS: A total of 16,097 children were enrolled and 466 (2.89%, 466/16,097) were HAdV-positive. The positive rates of HAdV varied, ranging from 4.39% (151/3,438) in 2018 to1.25% (26/2,081) in 2021, dropped from 3.19% (428/13,408) to 1.41% (38/2,689) from before to after NPIs launched (P < 0.001). There were 350 cases typed into nine types of species B, C, or E and 34 recorded as undetermined. Among them, HAdV-B3 (51.56%, 198/384) was the most prevalent types from 2015 to 2017, and HAdV-B7 (29.17%, 112/384) co-circulated with HAdV-B3 from 2018 to 2019. After NPIs launched, HAdV-B3 and B7 decreased sharply with HAdV-B7 undetected in 2021, while HAdV-C1 became the dominant one and the undetermined were more. CONCLUSIONS: The endemic pattern of HAdV changed in Beijing because of the NPIs launched for COVID-19. Especially, the dominant types changed from HAdV-B to HAdV-C.
Subject(s)
Adenovirus Infections, Human , Adenoviruses, Human , COVID-19 , Respiratory Tract Infections , Child , Humans , Beijing/epidemiology , Adenoviruses, Human/genetics , Phylogeny , Adenovirus Infections, Human/epidemiology , Adenovirus Infections, Human/prevention & control , COVID-19/epidemiology , COVID-19/prevention & control , China/epidemiology , Respiratory Tract Infections/epidemiology , Multiplex Polymerase Chain ReactionABSTRACT
Human adenovirus types 4 (HAdV4) and 7 (HAdV7) often lead to severe respiratory diseases and occur epidemically in children, adults, immune deficiency patients, and other groups, leading to mild or severe symptoms and even death. However, no licensed adenovirus vaccine has been approved in the market for general use. E3 genes of adenovirus are generally considered nonessential for virulence and replication; however, a few studies have demonstrated that the products of these genes are also functional. In this study, most of the E3 genes were deleted, and two E3-deleted recombinant adenoviruses (ΔE3-rAdVs) were constructed as components of the vaccine. After E3 deletion, the replication efficiencies and cytopathogenicity of ΔE3-rAdVs were reduced, indicating that ΔE3-rAdVs were attenuated after E3 genes deletion. Furthermore, single immunization with live-attenuated bivalent vaccine candidate protects mice against challenge with wild-type human adenovirus types 4 and 7, respectively. Vaccinated mice demonstrated remarkably decreased viral loads in the lungs and less lung pathology compared to the control animals. Taken together, our study confirms the possibility of the two live-attenuated viruses as a vaccine for clinic use and illustrates a novel strategy for the construction of an adenovirus vaccine.
Subject(s)
Adenovirus E3 Proteins/genetics , Adenovirus Infections, Human/prevention & control , Adenovirus Vaccines/immunology , Adenoviruses, Human/immunology , Vaccines, Attenuated/immunology , A549 Cells , Adenovirus Infections, Human/immunology , Adenoviruses, Human/classification , Animals , Cell Line , Female , Gene Deletion , HEK293 Cells , Humans , Mice , Mice, Inbred BALB C , Viral LoadABSTRACT
IMPORTANCE: Adenoviral conjunctivitis is highly contagious, can be associated with systemic infections, and can cause chronic visual impairment. It accounts for a large proportion of acute conjunctivitis. Outbreaks of epidemic keratoconjunctivitis (EKC) are costly in terms of productivity loss from work furloughs and spread to patients and have resulted in clinic and departmental closures. OBJECTIVE: To examine the institutional cost savings of a policy to diagnose adenoviral conjunctivitis and triage and furlough medical center employees with this condition to prevent outbreaks. DESIGN, SETTING, AND PARTICIPANTS: This quality improvement study assessed Johns Hopkins Medicine employees with red eye from November 1, 2011, through October 31, 2018, who were triaged at the occupational health clinic whose conditions were diagnosed using polymerase chain reaction (PCR) validated for adenoviral conjunctivitis. INTERVENTIONS: Only employees with positive PCR test results were furloughed, with furlough length tailored to subtype (a minimum of 2 weeks for EKC and 1 week otherwise). MAIN OUTCOMES AND MEASURES: Total number of furloughs avoided and cost savings associated with reducing unnecessary furloughs. RESULTS: Of 2142 employees with red eye, 1520 (71.0%) underwent PCR testing; 130 (8.6%) had positive adenoviral PCR test results, of whom 41 (31.5%) had EKC. Furloughing 130 employees with positive PCR test results vs furloughing all 1520 employees clinically suspected of having adenoviral conjunctivitis represented an estimated annual savings of $442â¯073, or $3â¯094â¯511 during 7 years. The cost of performing PCR on employees suspected of having adenoviral conjunctivitis was 5.0% of the cost associated with furloughing all employees with red eye. No outbreaks occurred. CONCLUSIONS AND RELEVANCE: In this quality improvement study, this policy, notable for development and use of PCR for adenoviral conjunctivitis on a large scale, resulted in substantial cost savings from fewer work furloughs compared with the number of employees who would have been furloughed based on clinical diagnosis. These results may provide impetus for policy adoption by other institutions and for development of a rapid, sensitive, and specific diagnostic test for adenoviral conjunctivitis.
Subject(s)
Adenovirus Infections, Human , Adenoviruses, Human , Conjunctivitis, Viral , Academic Medical Centers , Adenovirus Infections, Human/diagnosis , Adenovirus Infections, Human/epidemiology , Adenovirus Infections, Human/prevention & control , Adenoviruses, Human/genetics , Conjunctivitis, Viral/diagnosis , Conjunctivitis, Viral/prevention & control , Cost Savings , Humans , PolicyABSTRACT
PURPOSE: To analyze the epidemiologic characteristics of an outbreak of human adenovirus type 54 (HAdV-54) on Oki Island, Shimane Prefecture, Japan, in 2017 and to assess the effectiveness of a compartmentalization method in controlling the incidence and spread. STUDY DESIGN: Retrospective cohort study. METHODS: The infection was diagnosed in 136 individuals, and typing was confirmed by PCR and direct sequencing. The epidemiologic characteristics of the disease including the infection rate, incubation period, and basic reproductive number (R0), ie, number of cases directly infected by an infectious patient during the course of the disease, were investigated. The effectiveness of compartmentalization for infection control was determined by simulating the outbreak using the Susceptible-Exposed-Infectious-Recovered (SEIR) model. RESULTS: The majority of the HAdV-54-infected individuals were the children of 3 nursery schools (A, B, and C) and their parents on Oki Island. The infection rates in the 3 schools were 13.2%, 16.9%, and 17.2%, respectively. The one class of school B without the index case was initially compartmentalized, and the infection rate in this compartment was 0%. The incubation period was calculated to be 9.3 ± 3.5 days, and the disease duration, 13.0 ± 5.4 days. The R0 was 1.43. Using these parameters, a SEIR model was constructed. The SEIR model well predicted the daily incidence of infection and indicated that the compartmentalization method provides effective reduction in the incidence of the infection, with much earlier control. CONCLUSIONS: The compartmentalization method is effective to control HAdV-54 outbreaks.
Subject(s)
Adenovirus Infections, Human , Keratoconjunctivitis , Adenoviridae , Adenovirus Infections, Human/diagnosis , Adenovirus Infections, Human/epidemiology , Adenovirus Infections, Human/prevention & control , Child , Disease Outbreaks , Humans , Japan/epidemiology , Keratoconjunctivitis/diagnosis , Keratoconjunctivitis/epidemiology , Keratoconjunctivitis/prevention & control , Retrospective StudiesABSTRACT
OBJECTIVE: Ocular infections caused by human adenovirus are highly contagious and can cause outbreaks, especially in nursing homes. In this work, we describe the epidemiological and analytical research as well as the control measures carried out for a conjunctivitis outbreak. METHODS: Descriptive epidemiological study. Cases with a symptom onset date prior to oficial communication were analyzed retrospectively. The rest was analyzed prospectively. Conjunctival smears were collected for microbiological study. Virological analysis was performed by detecting adenovirus by PCR and genotyping. A data questionnaire that collected clinical and epidemiological information was designed. Possible risk factors associated with infection were studied by calculating the Odds Ratio. RESULTS: On June 11, 2019, the Epidemiological Surveillance Section of the Provincial Health Department of Albacete was notified of the existence of a large number of cases of conjunctivitis in a geriatric center. 54 cases were declared: 43 internal residents, 3 day center assistants and 8 workers. Attack rates were 35.8%, 12.5% and 8.4% respectively. Three risk factors were associated with the disease: patient´s lack of autonomy, being a resident at the nursing home and having their room assigned on the first floor. Human adenovirus serotype 8 was detected in the patients' samples. CONCLUSIONS: A high attack rate was observed in internal residents and the disease was associated with patient´s lack of autonomy and having their room assigned on the first floor of the nursing home. The outbreak was caused by human adenovirus serotype 8.
OBJETIVO: Las infecciones oculares causadas por adenovirus humanos son altamente contagiosas y pueden causar brotes, especialmente en residencias de ancianos. El objetivo de este trabajo fue exponer las investigaciones epidemiológicas y analíticas realizadas para el estudio del brote de queratoconjuntivitis epidémica y las medidas establecidas para su control. METODOS: Se realizó un estudio epidemiológico descriptivo. Se analizaron de forma retrospectiva los casos con fecha de inicio de síntomas anterior a la comunicación oficial, y de forma prospectiva el resto. Se recogieron frotis conjuntivales para estudio microbiológico. El análisis virológico fue realizado mediante la detección de adenovirus por PCR y genotipado. Se diseñó un cuestionario de datos que recogía información clínica y epidemiológica. Se estudiaron posibles factores de riesgo asociados a la infección mediante el cálculo de la Odds Ratio. RESULTADOS: El 11 de junio de 2019 se notificó a la Sección de Vigilancia Epidemiológica de la Dirección Provincial de Sanidad de Albacete la existencia de un número elevado de casos de conjuntivitis en un centro geriátrico. Se declararon 54 casos: 43 entre residentes internos, 3 entre asistentes del centro de día y 8 entre personal laboral. Las tasas de ataque fueron del 35,8%, 12,5% y 8,4%, respectivamente. La falta de autonomía, el ser residente interno y estar ubicado en la primera planta fueron factores asociados a la enfermedad. Se detectó adenovirus humano serotipo 8 en las muestras correspondientes a enfermos. CONCLUSIONES: Se observó una elevada tasa de ataque en residentes internos y la enfermedad se asoció con la falta de autonomía y la localización en la primera planta. El brote fue causado por adenovirus humano serotipo 8.
Subject(s)
Adenovirus Infections, Human/epidemiology , Adenoviruses, Human/genetics , Disease Outbreaks , Infection Control/methods , Keratoconjunctivitis/epidemiology , Keratoconjunctivitis/virology , Nursing Homes , Adenovirus Infections, Human/complications , Adenovirus Infections, Human/diagnosis , Adenovirus Infections, Human/prevention & control , Adenoviruses, Human/isolation & purification , Aged , Aged, 80 and over , Female , Humans , Keratoconjunctivitis/diagnosis , Keratoconjunctivitis/prevention & control , Male , Retrospective Studies , Risk Factors , Serogroup , Spain/epidemiologyABSTRACT
PURPOSE OF REVIEW: To review the roles of enteric adenovirus types 40 and 41 and nonenteric adenoviruses in the global burden of pediatric diarrhea. RECENT FINDINGS: Large studies using highly sensitive, type-specific molecular diagnostics have demonstrated a substantial and previously under-estimated burden of pediatric diarrheal disease because of enteric infections with adenovirus types 40/41. However, the true epidemiology of adenovirus 40/41 remains incompletely understood. Similarly, additional adenovirus types may also be implicated as agents of community-acquired pediatric gastroenteritis but current data are too limited to elucidate their epidemiological role(s), if any. SUMMARY: Efforts at global diarrhea control in low-income and middle-income countries will require combating pediatric gastroenteritis because of enteric adenovirus infections. Future research in these settings using type-specific molecular diagnostics or strain genotyping to fully characterize the epidemiology of adenovirus 40/41 infections, identify non-40/41 adenoviruses significantly associated with gastroenteritis, and develop vaccines effective at preventing adenovirus diarrhea is warranted.
Subject(s)
Adenovirus Infections, Human/epidemiology , Adenoviruses, Human/isolation & purification , Gastroenteritis/epidemiology , Gastroenteritis/virology , Acute Disease , Adenovirus Infections, Human/prevention & control , Adenovirus Infections, Human/virology , Adenovirus Vaccines/therapeutic use , Adenoviruses, Human/genetics , Adenoviruses, Human/immunology , Child , Child, Preschool , Diarrhea/epidemiology , Diarrhea/virology , Feces/virology , Gastroenteritis/prevention & control , Genotype , Humans , Immunoenzyme Techniques/methods , Infant , Polymerase Chain Reaction/methods , PovertyABSTRACT
RATIONALE: In 2019, a small HAdV55-associated outbreak of adenovirus infection occurred among the intensive care unit (ICU) staff in Xiangya Hospital of Central South University in Hunan Province, China, during the treatment of a patient. OBJECTIVE: To investigate the characteristics of a nosocomial adenovirus outbreak in an ICU. METHODS: We evaluated all the patients treated and the medical staff working in the ICU from August 1 to September 4, 2019. We further performed an epidemiological and molecular analysis for this outbreak from patient to healthcare workers and between healthcare workers. After the outbreak, we adopted exposure prevention and droplet prevention measures based on standard precautions. MEASUREMENTS AND MAIN RESULTS: Between August 1 and August 27, 2019, 27 cases of human adenovirus cross-infection were reported in our institution. Among the cases, eleven were doctors (41%), eleven were nurses (41%), three were respiratory therapists (11%), and two were caregivers (7%). The attack rate was 28.4%, and the fatality rate was 0. The results showed that contact with the index case, lack of hand hygiene or gloving adherence were risk factors for infection after adenovirus exposure. After taking specific precautions, no new cases of infection have appeared since August 27. CONCLUSIONS: Our results show that HAdV55 in a single patient had strong transmission potential in an intensive care unit with adequate facilities and standardized operation. We provide convincing evidence indicating that attention could be highlighted on the role of standard and specific precautions for controlling the spread of adenovirus in ICUs.
Subject(s)
Adenovirus Infections, Human/epidemiology , Cross Infection/epidemiology , Medical Staff/statistics & numerical data , Adenovirus Infections, Human/prevention & control , Adenovirus Infections, Human/virology , Adenoviruses, Human/classification , Adenoviruses, Human/genetics , Adenoviruses, Human/isolation & purification , Adenoviruses, Human/physiology , Adult , China/epidemiology , Cross Infection/prevention & control , Cross Infection/virology , Female , Hand Hygiene , Hospitals, Teaching/statistics & numerical data , Humans , Intensive Care Units/statistics & numerical data , Male , Middle Aged , Phylogeny , Tertiary Healthcare/statistics & numerical data , Young AdultABSTRACT
Human adenovirus type 3 (HAdV-3) encompasses 15-87% of all adenoviral respiratory infections. The significant morbidity and mortality, especially among the neonates and immunosuppressed patients, demand the need for a vaccine or a targeted antiviral against this type. However, due to the existence of multiple hexon variants (3Hv-1 to 3Hv-25), the selection of vaccine strains of HAdV-3 is challenging. This study was designed to evaluate HAdV-3 hexon variants for the selection of potential vaccine candidates and the use of hexon gene as a target for designing siRNA that can be used as a therapy. Based on the data of worldwide distribution, duration of circulation, co-circulation and their percentage among all the variants, 3Hv-1 to 3Hv-4 were categorized as the major hexon variants. Phylogenetic analysis and the percentage of homology in the hypervariable regions followed by multi-sequence alignment, zPicture analysis and restriction enzyme analysis were carried out. In the phylogram, the variants were arranged in different clusters. The HVR encoding regions of hexon of 3Hv-1 to 3Hv-4 showed 16 point mutations resulting in 12 amino acids substitutions. The homology in HVRs was 81.81-100%. Therefore, the major hexon variants are substantially different from each other which justifies their inclusion as the potential vaccine candidates. Interestingly, despite the significant differences in the DNA sequence, there were many conserved areas in the HVRs, and we have designed functional siRNAs form those locations. We have also designed immunogenic vaccine peptide epitopes from the hexon protein using bioinformatics prediction tool. We hope that our developed siRNAs and immunogenic vaccine peptide epitopes could be used in the future development of siRNA-based therapy and designing a vaccine against HAdV-3.
Subject(s)
Adenovirus Infections, Human/immunology , Adenovirus Infections, Human/virology , Adenoviruses, Human/genetics , Adenoviruses, Human/immunology , Capsid Proteins/genetics , Capsid Proteins/immunology , RNA, Small Interfering/therapeutic use , Adenovirus Infections, Human/prevention & control , Adenovirus Infections, Human/therapy , Amino Acid Substitution , Antibodies, Neutralizing/immunology , Capsid Proteins/chemistry , Computational Biology , Computer Simulation , Epitopes/immunology , Humans , Phylogeny , Point Mutation , Protein Binding , RNA, Small Interfering/chemistry , Respiratory Tract Infections/immunology , Respiratory Tract Infections/prevention & control , Respiratory Tract Infections/therapy , Respiratory Tract Infections/virology , Sequence Analysis, Protein , Viral Vaccines/genetics , Viral Vaccines/immunology , Virus Replication/drug effectsABSTRACT
Seven human mastadenovirus (HAdV) species (A-G) are known with more than 100 reported types. HAdV is highly resistant to common hand sanitizers. Epidemic keratoconjunctivitis and pharyngoconjunctival fever are caused by HAdV, which can be explosively transmitted in a confined space, resulting in outbreaks, such as nosocomial infections. Given the absence of an antiviral agent against the HAdV infection, it is important to prevent the spread of the infection by using disinfectants. Ozone has already been well-known for its bactericidal and virucidal effects. ALTANT is an ozonated alcohol preparation developed by E-TECH Co., Ltd. (Kobe, Hyogo, Japan). In this study, we mixed ALTANT with different HAdV types at a ratio of 9:1 and determined HAdV viability after instantaneous reactions for varying periods (flash to 5 minutes) using the TCID50 assay. The assay results demonstrated that the HAdV viability decreased by 1/10 to 1/100 within 1 minute after the reaction; additionally, slight differences in the reactivity were observed among the HAdV types. HAdV viability decreased by a factor of > 4log10, and the virus was eliminated within 3 minutes. This study demonstrated the potent HAdV disinfection effect of ALTANT.
Subject(s)
Adenovirus Infections, Human/prevention & control , Disinfectants/pharmacology , Ethanol/pharmacology , Mastadenovirus/drug effects , Ozone/pharmacology , Adenovirus Infections, Human/virology , Adenoviruses, Human , Anti-Infective Agents, Local/chemistry , Anti-Infective Agents, Local/pharmacology , Cell Proliferation/drug effects , Cross Infection/prevention & control , Cross Infection/virology , Disease Outbreaks , Disinfectants/chemistry , Ethanol/chemistry , Humans , Japan , Keratoconjunctivitis/prevention & control , Keratoconjunctivitis/virology , Mastadenovirus/pathogenicity , Microbial Sensitivity Tests , Ozone/chemistryABSTRACT
A respiratory outbreak associated with human adenovirus type 7 (HAdV-7) occurred among unvaccinated officer candidates attending initial military training. Respiratory infections associated with HAdV-7 can be severe, resulting in significant morbidity. Genomic sequencing revealed HAdV-7d, a genome type recently remerging in the United States as a significant respiratory pathogen, following reports from Southeast Asia. Twenty-nine outbreak cases were identified; this likely represents an underestimate. Although the HAdV type 4 and 7 vaccine is currently given to US military enlisted recruit trainees, it is not routinely given to officer candidates. Administration of the HAdV type 4 and 7 vaccine may benefit this cohort.
Subject(s)
Adenovirus Infections, Human/epidemiology , Adenoviruses, Human/genetics , Disease Outbreaks , Military Personnel , Respiratory Tract Infections/epidemiology , Adenovirus Infections, Human/diagnosis , Adenovirus Infections, Human/prevention & control , Adenovirus Infections, Human/virology , Adenovirus Vaccines/immunology , Adult , Base Sequence/genetics , Female , Humans , Male , Phylogeny , Respiratory Tract Infections/diagnosis , Respiratory Tract Infections/prevention & control , Respiratory Tract Infections/virology , Schools , Vaccination , Virginia/epidemiology , Whole Genome Sequencing , Young AdultABSTRACT
BACKGROUND: A number of serious human adenovirus (HAdV) outbreaks have been recently reported: HAdV-B7 (Israel, Singapore, and USA), HAdV-B7d (USA and China), HAdV-D8, -D54, and -C2 (Japan), HAdV-B14p1 (USA, Europe, and China), and HAdV-B55 (China, Singapore, and France). METHODS: To understand the epidemiology of HAdV infections in Singapore, we studied 533 HAdV-positive clinical samples collected from 396 pediatric and 137 adult patients in Singapore from 2012 to 2018. Genome sequencing and phylogenetic analyses were performed to identify HAdV genotypes, clonal clusters, and recombinant or novel HAdVs. RESULTS: The most prevalent genotypes identified were HAdV-B3 (35.6%), HAdV-B7 (15.4%), and HAdV-E4 (15.2%). We detected 4 new HAdV-C strains and detected incursions with HAdV-B7 (odds ratio [OR], 14.6; 95% confidence interval [CI], 4.1-52.0) and HAdV-E4 (OR, 13.6; 95% CI, 3.9-46.7) among pediatric patients over time. In addition, immunocompromised patients (adjusted OR [aOR], 11.4; 95% CI, 3.8-34.8) and patients infected with HAdV-C2 (aOR, 8.5; 95% CI, 1.5-48.0), HAdV-B7 (aOR, 3.7; 95% CI, 1.2-10.9), or HAdV-E4 (aOR, 3.2; 95% CI, 1.1-8.9) were at increased risk for severe disease. CONCLUSIONS: Singapore would benefit from more frequent studies of clinical HAdV genotypes to identify patients at risk for severe disease and help guide the use of new antiviral therapies, such as brincidofovir, and potential administration of HAdV 4 and 7 vaccine.
Subject(s)
Adenovirus Infections, Human/diagnosis , Adenovirus Infections, Human/epidemiology , Adenoviruses, Human/genetics , Diagnostic Tests, Routine/methods , Disease Outbreaks/prevention & control , Genotype , Respiratory Tract Infections/epidemiology , Adenovirus Infections, Human/drug therapy , Adenovirus Infections, Human/prevention & control , Adenovirus Vaccines/immunology , Adenovirus Vaccines/therapeutic use , Adenoviruses, Human/immunology , Adolescent , Adult , Antiviral Agents/therapeutic use , Child , Child, Preschool , DNA, Viral/genetics , Female , Humans , Infant , Male , Middle Aged , Phylogeny , Prospective Studies , Respiratory Tract Infections/drug therapy , Respiratory Tract Infections/prevention & control , Respiratory Tract Infections/virology , Retrospective Studies , Risk Factors , Severity of Illness Index , Singapore/epidemiology , Whole Genome SequencingABSTRACT
Human adenovirus (HAdV) is one of the common pathogens causing human respiratory infections and HAdV infection can result in a variety of diseases. In recent years, outbreaks of HAdV infection have been detected from time to time in China and clustered severe cases have been reported in some regions. This technical guideline has been timely developed to provide technical support on the control and prevention of HAdV respiratory infections. It provides an overview of etiology, epidemiology, clinical manifestations, and treatment principles of HAdV infection, determines the definitions of laboratory-confirmed cases, clinically diagnosed cases, severe and critically severe HAdV pneumonia cases. Then the workflow of case detecting and reporting, and the outbreak epidemic disposal has been formulated. Finally, the control and prevention measures in places at high risk for HAdV transmission and individual preventive measures also has been introduced.
Subject(s)
Adenovirus Infections, Human/prevention & control , Adenoviruses, Human , Practice Guidelines as Topic , Respiratory Tract Infections/prevention & control , Adenovirus Infections, Human/virology , China , Humans , Respiratory Tract Infections/virologyABSTRACT
Adenoviral infections continue posing a major threat in severely immunocompromised patients including particularly allogeneic stem cell transplant recipients. Although exogenous infections occur in some instances, the majority of invasive events appear to arise from viral reactivation. In the pediatric setting, adenoviruses were demonstrated to persist in the gastrointestinal tract, and the intestinal epithelium serves as the main site of viral replication preceding invasive infection. Regular monitoring of serial stool samples for the presence and load of adenoviruses has therefore become a routine diagnostic tool for post-transplant patient surveillance, and can serve as a trigger for early initiation of treatment. In the adult setting, the source of infection or reactivation is less clear, and monitoring of peripheral blood specimens is the predominant approach for patient surveillance. Timely initiation of antiviral treatment is reportedly required for prevention or successful control of disseminated disease mediated by adenoviruses, and appropriate diagnostic monitoring is therefore of paramount importance. Currently available antiviral agents and immune therapeutic approaches have not been able to entirely overcome the life-threatening courses of invasive adenoviral infections in the immunocompromised clinical setting.
Subject(s)
Adenovirus Infections, Human/diagnosis , Adenoviruses, Human/physiology , Blood/virology , Feces/virology , Stem Cell Transplantation/adverse effects , Adenovirus Infections, Human/drug therapy , Adenovirus Infections, Human/prevention & control , Adenoviruses, Human/pathogenicity , Adult , Age Factors , Antiviral Agents/therapeutic use , Child , Humans , Population Surveillance , Virus ActivationABSTRACT
Background and objectives: The use of antagonistic probiotic microorganisms and their byproducts represents a promising approach for the treatment of viral diseases. In the current work, the effect of exopolysaccharides (EPSs) produced by lactic acid bacteria from different genera on the structural and functional characteristics of cells and the development of adenoviral infection in vitro was studied. Materials and Methods: Cytotoxicity of six EPSs of lactic acid bacteria of the genera Lactobacillus, Leuconostoc and Pediococcus was determined by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay. The influence of the EPSs on the infectivity of human adenovirus type 5 (HAdV-5) and on the cell cycle under a condition of adenovirus infection was studied using plaque reduction assay and flow cytometric analysis, respectively. Results: It was shown that exopolysaccharides were non-toxic to Madin-Darby bovine kidney cells (MDBK) as they reduced their viability by 3-17%. A change in the distribution of the cell cycle phases in the non-infected cell population treated with EPSs was observed. The analysis demonstrated an increase in the number of cells in the S phase by 47% when using EPSs 15a and a decrease in the number of cells in the G1 phase by 20-27% when treated with the EPSs 15a, 33a, and 19s. The use of EPSs did not led to the normalization of the life cycle of HAdV-5 infected cells to the level of non-infected cells. The EPSs showed low virucidal activity and reduced the HAdV-5 infectivity to 85%. Among the studied exopolysaccharides, anti-adenovirus activity was found for EPS 26a that is produced by Lactobacillus spp. strain. The treatment of cells with the EPS following virus adsorption completely (100%) suppressed the formation and release of HAdV-5 infectious. Conclusions: EPS 26a possessed distinct anti-HAdV-5 activity and the obtained data demonstrate the potential of using exopolysaccharides as anti-adenoviral agents.
Subject(s)
Adenoviruses, Human/drug effects , Cell Cycle/drug effects , Lactobacillus/metabolism , Leuconostoc/metabolism , Pediococcus/metabolism , Polysaccharides, Bacterial/pharmacology , Adenovirus Infections, Human/prevention & control , Animals , Cell Line , Dogs , G1 Phase , Humans , Lactobacillales/metabolism , Polysaccharides, Bacterial/metabolism , S PhaseABSTRACT
Adenovirus type 7 (Ad7) infection is associated with acute respiratory disease (ARD), especially in military recruits living in close quarters. Recently, several outbreaks of Ad7 infections have occurred in civilian populations, with some cases leading to death. However, the current Ad7 vaccine is licensed for use only in military recruits because it utilizes an orally delivered wild type virus which is shed in the stool for 28 days after immunization. This poses a safety risk due to the possibility of virus spread to vulnerable populations. To address the need for a safer Ad7 vaccine for use in civilian populations, we developed a single-cycle Ad7 virus (scAd7). This scAd7 virus is deleted for the Ad7 fiber protein, so that viruses produced outside of complementing cells lines lack this essential structural protein and have severely reduced infectivity. In vitro studies in noncomplementing A549 cells showed that the scAd7 virus has genomic DNA replication kinetics and Ad7 hexon expression similar to a replication-competent virus; however, virus progeny produced after infection has impaired infectivity. Therefore, this scAd7 virus combines the safety advantages of a replication-defective virus with the increased Ad7 gene expression of a replication-competent virus. Due to these advantages, we believe that scAd7 viruses should be further studied as an alternative, safer Adenovirus 7 vaccine.
Subject(s)
Adenovirus Infections, Human/prevention & control , Adenovirus Vaccines/immunology , Adenoviruses, Human/immunology , Respiratory Tract Infections/prevention & control , Respiratory Tract Infections/virology , Acute Disease , Adenovirus Vaccines/genetics , Adenoviruses, Human/classification , Adenoviruses, Human/genetics , Animals , Capsid Proteins/genetics , Capsid Proteins/immunology , Cell Line, Tumor , Gene Expression , Genes, Reporter , Genetic Vectors/genetics , Humans , Immunogenicity, Vaccine , Mice , Mice, Transgenic , Virus ReplicationABSTRACT
Introduction: Human adenovirus (HAdV)-derived vectors have been used in numerous pre-clinical and clinical trials during the last 40 years. Current research in HAdV-based vaccines focuses on improving transgene immunogenicity and safety. Because pre-existing humoral immunity against HAdV types correlate with reduced vaccine efficacy and safety, many groups are exploring the development of HAdV types vectors with lower seroprevalence. However, global seroepidemiological data are incomplete. Areas covered: The goal of this review is to centralize 65 years of research on (primarily) HAdV epidemiology. After briefly addressing adenovirus biology, we chronical HAdV seroprevalence studies and highlight major milestones. Finally, we analyze data from about 50 studies with respect to HAdVs types that are currently used in the clinic, or are in the developmental pipeline. Expert opinion: Vaccination is among the most efficient tools to prevent infectious disease. HAdV-based vaccines have undeniable potential, but optimization is needed and antivector immunity remains a challenge if the same vectors are to be administrated to different populations. Here, we identify gaps in our knowledge and the need for updated worldwide epidemiological data.
Subject(s)
Adenovirus Infections, Human/epidemiology , Adenovirus Infections, Human/immunology , Adenovirus Infections, Human/prevention & control , Adenoviruses, Human/immunology , Adenovirus Infections, Human/classification , Adenovirus Vaccines/immunology , Adenoviruses, Human/genetics , Adenoviruses, Human/isolation & purification , Clinical Trials as Topic , DNA, Viral/genetics , DNA, Viral/isolation & purification , Genetic Therapy , Genetic Vectors , Humans , Incidence , Seroepidemiologic Studies , VaccinationABSTRACT
BACKGROUND: Human adenoviruses (HAdVs) are associated with significant morbidity and death after hematopoietic cell transplantation (HCT). In this study, we sought to determine the incidence of HAdV infection among pediatric HCT recipients in the polymerase chain reaction (PCR) testing era, identify risk factors for viremia among patients undergoing HAdV surveillance, and assess the effectiveness of preemptive cidofovir. METHODS: A single-center retrospective cohort of patients who underwent a transplant within a 10-year period was assembled. The incidence of and outcomes of patients with HAdV infection and disease were determined by PCR results and chart review. A Cox regression model was used for surveilled allogeneic HCT recipients to identify factors associated with viremia. We also used a discrete-time failure model with inverse probability treatment weights to assess the effectiveness of preemptive cidofovir for infection. RESULTS: Among 572 HCT recipients, 76 (13.3%) had ≥1 sample that was HAdV PCR positive (3.5% of autologous HCT recipients and 19.7% of allogeneic HCT recipients). Among 191 allogeneic HCT recipients under surveillance, 58 (30.4%) had HAdV detected from any source, and 50 (26.2%) specifically had viremia. The mortality rate was higher in allogeneic HCT recipients with HAdV infection versus those without infection (25.9% vs 11.3%; P = .01). Factors associated with infection included an age of 6 to 12 years, an absolute lymphocyte count of <200 cells/µL, recent prednisone exposure, and recent bacteremia. Preemptive cidofovir was not associated with a reduced risk of infection progression (odds ratio, 0.96 [95% confidence interval, 0.30-3.05]). CONCLUSIONS: HAdV infection is common and associated with an increased rate of death after allogeneic HCT. Using prediction models that incorporate factors associated with HAdV might help target surveillance. Preemptive cidofovir therapy was not protective in a subset of HAdV-positive patients. Larger observational or randomized investigations are necessary, because the utility of surveillance requires effective preemptive therapies.
Subject(s)
Adenovirus Infections, Human/epidemiology , Adenoviruses, Human/isolation & purification , Hematopoietic Stem Cell Transplantation/adverse effects , Adenovirus Infections, Human/prevention & control , Allografts , Bacteremia , Child , Child, Preschool , Cidofovir/therapeutic use , DNA, Viral/blood , Female , Hematopoietic Stem Cell Transplantation/mortality , Humans , Incidence , Male , Proportional Hazards Models , Retrospective Studies , Risk Factors , Treatment Outcome , Viremia/epidemiologyABSTRACT
Background and objectives: A considerable increase in the levels of adenoviral diseases among both adults and children necessitate the development of effective methods for its prevention and treatment. The synthesis of the new fluorinated 1,2,3-triazoles, and the study of the mechanisms of their action, are promising for the development of efficient antiviral drugs of our time. Materials and Methods: Antiviral activity and cell cytotoxic effect of 2-(3-chlorotetrahydrofuran-2-yl)-4-tosyl-5-(perfluoropropyl)-1,2,3-triazole (G29) were determined by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay. The influence of the compound on the infectivity of human adenovirus type 5 (HAdV-5) was carried out via the cytomorphology method. The influence of the compound on the cell cycle under a condition of adenovirus infection was studied using flow cytometric analysis of propidium iodide-stained cells. Results: It was found that G29 suppressed HAdV-5 reproduction by 50% in concentrations of 37 µg/mL. Furthermore, the compound reduced the titer of virus obtained de novo, and inhibited HAdV-5 inclusion bodies formation by 84â»90%. The use of fluorinated compounds under the conditions of adenovirus infection decreased the number of apoptotic cells by 11% and the number of cells in S phase by 21â»42% compared to the profile of infected cells. Conclusions: The fluorinated compound G29 showed moderate activity against HAdV-5 based on several mechanisms. It led to the normalization of the life cycle of cells infected with adenovirus to the level of non-infected cells and caused the obstruction of HAdV-5 reproduction, inducing the formation of non-infectious virus progeny.
Subject(s)
Adenoviruses, Human/drug effects , Antiviral Agents/chemical synthesis , Antiviral Agents/pharmacology , Fluorine Compounds/chemical synthesis , Fluorine Compounds/pharmacology , Triazoles/chemical synthesis , Triazoles/pharmacology , Adenovirus Infections, Human/drug therapy , Adenovirus Infections, Human/prevention & control , Animals , Antiviral Agents/chemistry , Antiviral Agents/therapeutic use , Casein Kinase II/antagonists & inhibitors , Cattle , Cell Cycle/drug effects , Cell Line , Cell Survival/drug effects , Fluorine Compounds/chemistry , Fluorine Compounds/therapeutic use , Microscopy, Fluorescence , Molecular Mimicry , Triazoles/chemistry , Triazoles/therapeutic use , Virus Replication/drug effectsABSTRACT
Novel adenovirus genotypes are associated with outbreaks of disease, such as acute gastroenteritis, renal disease, upper respiratory tract infection and keratoconjunctivitis. Here, we identify novel and variant adenovirus genotypes in children coinfected with enterotoxigenic Escherichia coli, in Bangladesh. Metagenomic sequencing of stool was performed and whole adenovirus genomes were extracted. A novel species D virus, designated genotype 90 (P33H27F67) was identified, and the partial genome of a putative recombinant species B virus was recovered. Furthermore, the enteric types HAdV-A61 and HAdV-A40 were found in stool specimens. Knowledge of the diversity of adenovirus genomes circulating worldwide, especially in low-income countries where the burden of disease is high, will be required to ensure that future vaccination strategies cover the diversity of adenovirus strains associated with disease.
Subject(s)
Adenovirus Infections, Human/genetics , Adenoviruses, Human/genetics , Gastroenteritis/virology , Genome, Viral , Genotype , Keratoconjunctivitis/virology , Adenovirus Infections, Human/epidemiology , Adenovirus Infections, Human/prevention & control , Adenoviruses, Human/isolation & purification , Bangladesh/epidemiology , Child , Child, Preschool , Feces/virology , Female , Gastroenteritis/epidemiology , Gastroenteritis/genetics , Gastroenteritis/prevention & control , Humans , Keratoconjunctivitis/epidemiology , Keratoconjunctivitis/genetics , Keratoconjunctivitis/prevention & control , MaleABSTRACT
Las infecciones víricas por Epstein-Barr (EBV) y Adenovirus (AdV) representan una causa significativa de morbi-mortalidad en pacientes sometidos a un trasplante alogénico de progenitores hematopoyéticos debido al uso de tratamientos inmunomielosupresores y al prolongado periodo de inmunodeficiencia que generan. Hasta el momento, se ha demostrado el papel protector post-trasplante de los linfocitos T CD8+ (CTLs) específicos de EBV y AdV. Sin embargo, otros factores son cada vez más importantes en la regulación de la reconstitución y actividad de CTLs específicos para estos virus, como las diferentes subpoblaciones celulares (linfocitos T CD4+, linfocitos T reguladores, células dendríticas, células Natural Killer, etc.), mecanismos moleculares de inmunoregulación y los fármacos administrados al paciente como profilaxis para una posible enfermedad de injerto contra huésped. El objetivo de esta revisión es analizar la importancia de la monitorización de la respuesta celular específica funcional frente a EBV y AdV en el manejo de los pacientes post-trasplante
Epstein-Barr (EBV) and Adenovirus (AdV) viral infections represent a significant cause of morbi-mortality in allogeneic hematopoietic stem cell transplantation recipients due to the use of immunomyelosuppressive treatments and the prolonged period of immunodeficiency that they generate. To date, the post-transplant protective role of EBV and AdV specific CD8+ T lymphocytes (CTLs) has been demonstrated. However, other factors are increasingly important in regulating the reconstitution and activity of CTLs specific to these viruses such as different cell subpopulations (CD4 + T lymphocytes, regulatory T lymphocytes, dendritic cells, Natural Killer cells, etc.), molecular mechanisms of immunoregulation and the drugs administered to the patient as prophylaxis for a possible graft-versus-host disease. The aim of this review is to analyze the importance of monitoring the functional EBV and AdV-specific cellular response in the management of post-transplant recipients