Application of Human Adenovirus Genotyping by Phylogenetic Analysis in an Outbreak to Identify Nosocomial Infection

Nosocomial infections are common in pediatric patients and can be fatal in infants and immunocompromised patients. In September 2018, a high positive rate of human adenovirus HAdV was occurred among hospitalized children in the Children's Hospital Affiliated to the Capital Institute of Paediatrics in Beijing. To investigate whether this outbreak of HAdV was related to nosocomial infections or the result of community infections, we collected respiratory specimens from patients with acute respiratory infections in a respiratory ward during June to December 2018, and screened for respiratory viruses. Among 1,840 cases included, 95(5.2%, 95/1840) were positive for HAdV and 81 were genotyped based on phylogenetic analysis, including seven as HAdV-1(8.6%), 30 HAdV-3(37.0%), two HAdV-6(2.5%), and 42 HAdV-7(51.9%). More HAdV-positive samples were collected in August(4.7%, 12/255), September(15.0%, 41/274) and October(6.9%, 17/247), with a peak in September 2018. By combining the results of HAdV phylogenetic analysis with clinical data of patients, there were 77 cases(4.2%, 77/1840; 81.1%, 77/95) excluded from nosocomial infections, eight cases representing possible infections transmitted by visitors or attending parents, three cases without sequences that might have been due to infection transmitted by roommates positive for HAdV, one case of a roommate without an HAdV sequence, and six cases that shared highly homologous sequences with those of their roommates, for which nosocomial infections might be considered. In conclusion, genotyping of HAdVs based on phylogenetic analysis combined with clinical information provides a powerful method to distinguish nosocomial infections from community acquired infection, especially when tracing the origins of nosocomial infections.     

Adenoviruses Associated with Acute Respiratory Diseases Reported in Beijing from 2011 to 2013

Background

Adenovirus is one of the most common causes of viral acute respiratory infections. To identify the types of human adenoviruses (HAdVs) causing respiratory illness in Beijing, a sentinel surveillance project on the viral aetiology of acute respiratory infection was initiated in 2011.

Principal findings

Through the surveillance project, 4617 cases of respiratory infections were identified during 2011-2013. Throat swabs (pharynx and tonsil secretions) were collected from all the patients, and 15 different respiratory viruses were screened by multiplex one-step PCR method. 45 were identified as adenovirus-positive from sporadic and outbreak cases of respiratory infection by a multiplex one-step RT-PCR method, and a total of 21 adenovirus isolates were obtained. Five HAdV types among three species, including HAdV-3 (species HAdV-B), HAdV-4 (species HAdV-E), HAdV-7 (species HAdV-B), HAdV-55 (species HAdV-B), and an undefined HAdV type (species HAdV-C) were identified. The comparison results of the penton base, hexon, and fiber gene sequences of the Beijing HAdV-3, HAdV-4, HAdV-7, and HAdV-55 strains in this study and those from the GenBank database indicated significant spatial and temporal conservation and stability of sequences within the genome; however, the phylogenetic relationship indicated that both strain BJ04 and strain BJ09 isolated in 2012 and 2013, respectively, may have recombined between HAdV-1 genome and HAdV-2 genome within species HAdV-C, indicating intraspecies recombination.

Conclusions

This study confirmed that at least 5 HAdV types including HAdV-3, HAdV-4, HAdV-7, HAdV-55 and an undefined HAdV type were co-circulating and were the causative agents of respiratory tract infections in recent years in Beijing. HAdV-3, HAdV-4, HAdV-7, and HAdV-55 showed the apparent stability of the genomes, while intraspecies recombination was identified in strain BJ04 and BJ09. The recombinants carrying penton base gene of HAdV-1 as well as hexon and fiber genes of HAdV-2 might be a novel type of HAdV worthy of further study.     

Genetic Analysis of Human Adenovirus Type 7 Strains Circulating in Different Parts of China

To investigate the molecular epidemiology and genetic variation of human adenovirus type 7(HAdV-7) in children with acute respiratory infections(ARI) in China. HAdV-7-positive respiratory samples collected from children with ARI in Beijing, Shijiazhuang, Wenzhou and Guangzhou from 2014–2018 were selected for gene amplification and sequence analysis. Fifty-seven HAdV-7 clinical strains with hexon, penton base and fiber gene sequences were obtained. Meanwhile17 strains were selected randomly from different cities for whole genome sequencing. Phylogenetic and variation analyses were performed based on the obtained sequences, HAdV-7 prototype strain Gomen(AY594255), vaccine strains(AY495969 and AY594256) and representative sequences of strains. The phylogenetic trees constructed based on whole genome sequences, major capsid protein genes(hexon, penton base and fiber) and the early genes(E1, E2, E3 and E4) were not completely consistent. The HAdV-7 strains obtained in this study always clustered with most of the circulating strains worldwide from the 1980 s to the present. Compared with the HAdV-7 prototype strain Gomen(AY594255), some amino acid mutations in loop1 and loop2 of hexon and the RGD loop region of the penton base gene were observed. Recombination analysis showed that partial regions of 55 k Da protein and 100 kDa hexon-assembly associated protein genes among all HAdV-7 strains in this study were from HAdV-16 and HAdV-3, respectively. Our study demonstrated the molecular evolution characteristics of HAdV-7 strains circulating in China and provided basic reference data for the prevention, control and vaccine development of HAdV-7.     

Severe Community-Acquired Pneumonia Caused by Human Adenovirus in Immunocompetent Adults: A Multicenter Case Series

Background

Severe community-acquired pneumonia (CAP) caused by human adenovirus (HAdV), especially HAdV type 55 (HAdV-55) in immunocompetent adults has raised increasing concerns. Clinical knowledge of severe CAP and acute respiratory distress syndrome induced by HAdV-55 is still limited, though the pathogen has been fully characterized by whole-genome sequencing.

Methods

We conducted a multicentre retrospective review of all consecutive patients with severe CAP caused by HAdV in immunocompetent adults admitted to the Emergency Department Intensive Care Unit of two hospitals in Northern China between February 2012 and April 2014. Clinical, laboratory, radiological characteristics, treatments and outcomes of these patients were collected and analyzed.

Results

A total of 15 consecutive severe CAP patients with laboratory-confirmed adenovirus infections were included. The median age was 30 years and all cases were identified during the winter and spring seasons. HAdV-55 was the most frequently (11/15) detected HAdV type. Persistent high fever, cough and rapid progression of dyspnea were typically reported in these patients. Significantly increased pneumonia severity index (PSI), respiratory rate, and lower PaO₂/FiO₂, hypersensitive CRP were reported in non-survivors compared to survivors (P = 0.013, 0.022, 0.019 and 0.026, respectively). The rapid development of bilateral consolidations within 10 days after illness onset were the most common radiographic finding, usually accompanied by adjacent ground glass opacities and pleural effusions. Total mortality was 26.7% in this study. Corticosteroids were prescribed to 14 patients in this report, but the utilization rate between survivors and non-survivors was not significant.

Conclusions

HAdV and the HAdV-55 sub-type play an important role among viral pneumonia pathogens in hospitalized immunocompetent adults in Northern China. HAdV should be tested in severe CAP patients with negative bacterial cultures and a lack of response to antibiotic treatment, even if radiologic imaging and clinical presentation initially suggest bacterial pneumonia.     

Frequent Detection of Human Adenovirus from the Lower Gastrointestinal Tract in Men Who Have Sex with Men

Background

The association between baseline seropositivity to human adenovirus (HAdV) type 5 and increased HIV acquisition in the Step HIV Vaccine Study has raised questions concerning frequency of acquired and/or persistent Adenovirus infections among adults at high risk of HIV-1 infection.

Methodology

To evaluate the frequency and pattern of HAdV shedding from the lower GI tract, we retrospectively tested rectal swabs for HAdVs in a cohort of 20 HSV-2 positive HIV-positive Peruvian men who have sex with men (MSM) undergoing rectal swabbing three times/week for 18 consecutive weeks, in a prospective study of HSV-2 suppression in HIV infection. Viral DNA was extracted and amplified using a sensitive multiplex PCR assay that detects all currently recognized HAdV types. Molecular typing of viruses was performed on selected samples by hexon gene sequencing. Baseline neutralizing antibody titers to HAdVs −5, −26, −35 and −48 were also assessed.

Principal Findings

15/20 individuals had HAdV detected during follow up. The median frequency of HAdV detection was 30% of samples (range 2.0% to 64.7%). HAdV shedding typically occurred on consecutive days in clustered episodes lasting a median of 4 days (range 1 to 9 days) separated by periods without shedding, suggesting frequent new infections or reactivation of latent infections over time. 8 of the 15 shedders had more than one type detected in follow-up. 20 HAdV types from species B, C, and D were identified, including HAdV-5, −26 and −48, HAdV types under development as potential vaccine candidates. 14/20 subjects were seropositive for HAdV-5; 15/20 for HAdV-26; 3/20 for HAdV-35; and 2/20 for HAdV-48. HAdV shedding did not correlate with CD4 count, plasma HIV-1 viral load, or titers to HAdV-5 or HAdV-35. The sole individual with HAdV-5 shedding was HAdV-5 seropositive.

Conclusions

HAdV shedding was highly prevalent and diverse, including types presently under consideration as HIV vaccine vectors. Subclinical HAdV infection of the GI tract is common among MSM in Peru; the prevalence of HAdV in the enteric tract should be evaluated in other populations. The association between ongoing recent enteric HAdV and the immune response to recombinant HAdV vaccines should be evaluated.     

Seroprevalence of neutralizing antibodies against adenovirus type 26 and 35 in healthy populations from Guangdong and Shandong provinces,China

Human adenoviruses type 26 (HAdV26) and type 35 (HAdV35) have increasingly become the choice of adenovirus vectors for vaccine application. However, the population pre-existing immunity to these two adenoviruses in China, which may reduce vaccine efficacy, remains largely unknown. Here, we established micro-neutralizing (MN) assays to investigate the seroprevalence of neutralizing antibodies (nAbs) against HAdV26 and HAdV35 in the general population of Guangdong and Shandong provinces, China. A total of 1184 serum samples were collected, 47.0% and 15.8% of which showed HAdV26 and HAdV35 nAb activity, respectively. HAdV26-seropositive individuals tended to have more moderate nAbs titers (201–1000), while HAdV35-seropositive individuals appeared to have more low nAbs titers (72–200). The seropositive rates of HAdV26 and HAdV35 in individuals younger than 20 years old were very low. The seropositive rates of HAdV26 increased with age before 70 years old and decreased thereafter, while HAdV35 seropositive rates did not show similar characteristics. Notably, the seropositive rates and nAb levels of both HAdV26 and HAdV35 were higher in Guangdong Province than in Shandong Province, but did not exert significant differences between males and females. The seroprevalence between HAdV26 and HAdV35 showed little correlation, and no significant cross-neutralizing activity was detected. These results clarified the characteristics of the herd immunity against HAdV26 and HAdV35, and provided information for the rational development and application of HAdV26 and HAdV35 as vaccine vectors in China.     

广州地区人腺病毒5型血清流行病学初步调查

目的评估广州地区人群中人腺病毒5型(HAdV-5)先存中和抗体的流行情况。方法采用以β-半乳糖苷酶(LacZ)为报告基因,结合CMV启动子的人重组腺病毒5型,使用化学发光法,检测了209份免疫功能正常的成人血清样本中HAdV-5的中和抗体阳性率情况。结果 HAdV-5中和抗体的阳性率为82.3%(172/209)。HAdV-5中和抗体在<1/20(低滴度)、1/40-1/160(中滴度)、1/320-1/1280(高滴度)、>1/1280(超高滴度)时均能检测到,而且随着滴度的增加,阳性率逐渐升高。在20～40岁时HAdV-5中和抗体阳性率最高,在<20岁时HAdV-5阳性率最低。结论广州地区人群中针对HAdV-5的先存中和抗体阳性率高,应用基于该种DNA病毒作为载体进行基因疫苗及基因治疗的研究时,具有一定的局限性。     

Phylogenetic analysis of the main neutralization and hemagglutination determinants of all human adenovirus prototypes as a basis for molecular classification and taxonomy

Human adenoviruses (HAdV) are responsible for a wide spectrum of diseases. The neutralization epsilon determinant (loops 1 and 2) and the hemagglutination gamma determinant are relevant for the taxonomy of HAdV. Precise type identification of HAdV prototypes is crucial for detection of infection chains and epidemiology. epsilon and gamma determinant sequences of all 51 HAdV were generated to propose molecular classification criteria. Phylogenetic analysis of epsilon determinant sequences demonstrated sufficient genetic divergence for molecular classification, with the exception of HAdV-15 and HAdV-29, which also cannot be differentiated by classical cross-neutralization. Precise sequence divergence criteria for typing (<2.5% from loop 2 prototype sequence and <2.4% from loop 1 sequence) were deduced from phylogenetic analysis. These criteria may also facilitate identification of new HAdV prototypes. Fiber knob (gamma determinant) phylogeny indicated a two-step model of species evolution and multiple intraspecies recombination events in the origin of HAdV prototypes. HAdV-29 was identified as a recombination variant of HAdV-15 (epsilon determinant) and a speculative, not-yet-isolated HAdV prototype (gamma determinant). Subanalysis of molecular evolution in hypervariable regions 1 to 6 of the epsilon determinant indicated different selective pressures in subclusters of species HAdV-D. Additionally, gamma determinant phylogenetic analysis demonstrated that HAdV-8 did not cluster with -19 and -37 in spite of their having the same tissue tropism. The phylogeny of HAdV-E4 suggested origination by interspecies recombination between HAdV-B (hexon) and HAdV-C (fiber), as in simian adenovirus 25, indicating additional zoonotic transfer. In conclusion, molecular classification by systematic sequence analysis of immunogenic determinants yields new insights into HAdV phylogeny and evolution.     

Outbreak of acute respiratory disease caused by human adenovirus type 7 in a military training camp in Shaanxi,China

Outbreaks of ARD associated with HAdV have been reported in military populations in many countries. Here, we report an ARD outbreak caused by HAdV‐7 in a military training camp in Shaanxi Province, China, from February to March of 2012. Epidemic data and samples from the patients were collected, and viral nucleotides from samples and viral isolations were detected and sequenced. IgG and IgA antibodies against HAdV, and the neutralization antibodies against the viral strain isolated in this outbreak, were detected. Epidemiological study showed that all personnel affected were males with an average age of 19.1 years. Two peaks appeared on the epicurve and there was an 8‐day interval between peaks. Laboratory results of viral nucleotide detection carried out with clinical specimens were positive for HAdV (83.33%, 15/18). Further study through serum antibody assay, virus isolation and phylogenetic analysis showed that HAdV‐7 was the etiological agent responsible for the outbreak. IgA antibody began to appear on the 4th day after the onset and showed 100% positivity on the 8th day. The virus strain in the present outbreak was highly similar to the virus isolated in Hanzhong Shaanxi in 2009. We conclude that HAdV‐7 was the pathogen corresponding to the outbreak, and this is the first report of an ARD outbreak caused by HAdV‐7 in military persons in China. Vaccine development, as well as enhanced epidemiological and virological surveillance of HAdV infections in China should be emphasized.     

Molecular Typing and Epidemiology Profiles of Human Adenovirus Infection among Paediatric Patients with Severe Acute Respiratory Infection in China

Background

Human adenoviruses (HAdVs) have been recognised as pathogens that cause a broad spectrum of diseases. The studies on HAdV infection among children with severe acute respiratory infection (SARI) are limited.

Objective

To investigate the prevalence, epidemiology, and genotype of HAdV among children with SARI in China.

Study Design

Nasopharyngeal aspirates (NPAs) or induced sputum (IS) was collected from hospitalised children with SARIs in Beijing (representing Northern China; n = 259) and Zhejiang Province (representing Eastern China; n = 293) from 2007 to 2010. The prevalence of HAdV was screened by polymerase chain reaction (PCR), followed by sequence typing of PCR fragments that targeted the second half of the hexon gene. In addition, co-infection with other human respiratory viruses, related epidemiological profiles and clinical presentations were investigated.

Results and Conclusions

In total, 76 (13.8%) of 552 SARI patients were positive for HAdV, and the infection rates of HAdV in Northern and Eastern China were 20.1% (n = 52) and 8.2% (n = 24), respectively. HAdV co-infection with other respiratory viruses was frequent (infection rates: Northern China, 90.4%; Eastern China, 70.8%). The peak seasons for HAdV-B infection was winter and spring. Additionally, members of multiple species (Human mastadenovirus B, C, D and E) were circulating among paediatric patients with SARI, of which HAdV-B (34/52; 65.4%) and HAdV-C (20/24, 83.3%) were the most predominant in Northern and Eastern China, respectively. These findings provide a benchmark for future epidemiology and prevention strategies for HAdV.     

Seroprevalence of Neutralizing Antibodies against Six Human Adenovirus Types Indicates the Low Level of Herd Immunity in Young Children from Guangzhou,China

Human adenoviruses(HAdVs) commonly cause many diseases such as respiratory diseases, gastroenteritis, cystitis worldwide. HAdV-3,-7,-4 and emergent HAdV-55 and HAdV-14 are the most important types causing severe respiratory diseases. There is no effective drug available for clinical treatment, and no vaccine available for the general population.Therefore, it is important to investigate the seroprevalence against HAdV for developing novel vaccines and vectors. In this study, we investigated the seroprevalence and titer levels of neutralizing antibodies(NAb) against HAdV-3,-4,-7,-14,-55,and-11 in total 278 healthy populations between 0 months and 49 years of age(228 children and 50 adults) from Guangzhou. In children under the age of 18 years, the seropositive rates were significantly increased against HAdV-3 at12.07%, 33.96%, and 64.29% and against HAdV-7 at 0%, 18.87%, and 19.05% in age groups of 1–2, 3–5, and 6–17 years,respectively. The seroprevalence was very low(0% * 8.1%) for all other four types. In adults aged between 18 and49 years, HAdV-3,-4, and-7([ 50.00%) were the most common types, followed by HAdV-14(38.00%),-55(34.00%),and-11(24.00%). Adults tended to have high NAb titers against HAdV-4 and-55. HAdV-55-seropositive donors tended to be HAdV-11-and HAdV-14-seropositive. These results indicated the low level of herd immunity against all six HAdV types in young children, and HAdV-14,-55,-11 in adults from Guangzhou City. Our findings demonstrate the importance of monitoring HAdV types and developing vaccines against HAdV for children and adults.     

乳酸脱氢酶基因调控对HEK-293细胞代谢和腺病毒生产的影响

减少乳酸积累一直是哺乳动物细胞生物技术产业的一个目标。体外培养动物细胞时,乳酸积累主要是2种代谢途径作用的综合结果:一方面,葡萄糖在乳酸脱氢酶A(lactate dehydrogenase A,LDHA)的作用下生成乳酸;另一方面,乳酸可通过乳酸脱氢酶B(LDHB)或乳酸脱氢酶C(LDHC)氧化为丙酮酸重新进入三羧酸循环。本研究综合评估了乳酸代谢关键基因调控对人胚胎肾细胞(human embryonic kidney 293 cells,HEK-293)细胞生长、代谢和人腺病毒(human adenovirus,HAdV)生产的影响,有效提高了HEK-293细胞的HAdV生产能力,并为哺乳动物细胞的乳酸代谢工程调控提供了理论基础。通过改造乳酸代谢关键调控基因(敲除ldha基因以及过表达ldhb和ldhc基因),有效改善了HEK-293细胞的物质和能量代谢效率,显著提高了HAdV的生产。与对照细胞相比,3个基因改造均能促进细胞生长,降低乳酸和氨的积累,明显增强细胞的物质和能量代谢效率,显著提高了HEK-293细胞的HAdV生产能力。ldhc基因过表达对HEK-293细胞的生长、代谢和HAdV生产调控最显著,最大细胞密度提高了约38.7%,乳酸对葡萄糖得率和氨对谷氨酰胺得率分别下降了33.8%和63.3%,HAdV滴度提高了至少16倍。此外,相比于对照细胞株,改造细胞株的腺苷三磷酸(adenosine triphosphate,ATP)生成速率、ATP/O_(2)比率、ATP与腺苷二磷酸(adenosine diphosphate,ADP)的比值以及还原型辅酶Ⅰ(nicotinamide adenine dinucleotide,NADH)含量均有不同程度的提高,能量代谢效率明显改善。     

Detection and molecular characterization of adenoviruses in Korean children hospitalized with acute gastroenteritis

Human adenoviruses (HAdVs) are an important cause of acute gastroenteritis in children. However, few studies on the epidemiology or types of HAdVs associated with acute gastroenteritis have been conducted in Korea. Therefore, in the present study, the incidence of HAdV in 2064 stool samples from Korean children hospitalized with acute gastroenteritis (2004-2006) was assessed and the types of viruses present determined. Polymerase chain reaction, sequencing, and phylogenic analyses revealed that 113 samples (5.5%) were HAdV-positive. While HAdVs were mainly detected during July to October, no seasonal difference between the enteric and non-enteric viruses in the incidence of HAdV was observed. HAdV-41 and HAdV-40 were found in 54 (47.8%) and 3 (2.6%) HAdV-positive samples, respectively. HAdV-3, HAdV-7, HAdV-2, HAdV-31, HAdV-4, and HAdV-37 were detected in 11 (9.7%), 5 (4.4%), 2 (1.7%), 2 (1.7%), 1 (0.8%), and 1 (0.8%) of sample(s), respectively. Thus, not only enteric, but also non-enteric, HAdVs may play an important role in acute gastroenteritis in Korean children.     

Inhibition of HAdV-14 induced apoptosis by selenocystine through ROS-mediated PARP and p53 signaling pathways

BackgroundHuman Adenovirus (HAdV) can cause severe respiratory symptoms in people with low immunity and there is no targeted treatment for adenovirus infection. Anti-adenoviral drugs have high clinical significance for inhibiting adenovirus infection. Selenium (Se) plays an important role in anti-oxidation, redox signal transduction, and redox homeostasis. The excellent biological activity of Se is mainly achieved by being converted into selenocystine (SeC). Se participates in the active sites of various selenoproteins in the form of SeC. The ability of SeC to resist the virus has raised high awareness due to its unique antioxidative activity in recent years. The antiviral ability of the SeC was determined by detecting the infection rate of the virus in the cells.MethodsThe experiment mainly investigated the antiviral mechanism of SeC by locating the virus in the cell, detecting the generation of ROS, observing the DNA status of the cell, and monitoring the mitochondrial membrane potential.ResultsIn the present study, SeC was designed to resist A549 cells infections caused by HAdV-14. SeC could prevent HAdV-14 from causing cell apoptosis-related to DNA damage. SeC significantly inhibited ROS generation and protect the cells from oxidative damage induced by ROS against HAdV-14. SeC induced the increase of antiviral cytokines such as IL-6 and IL-8 by activating the Jak2 signaling pathway, and repaired DNA lesions by suppressing ATR, p53, and PARP signaling pathways.ConclusionSeC might provide an effective selenium species with antiviral properties for the therapies against HAdV-14.     

Comparison of the Virulence of Methicillin-Resistant and Methicillin-Sensitive Staphylococcus aureus

The virulence of methicillin-resistant Staphylococcus aureus (MRSA) was compared with that of methicillin-sensitive S. aureus (MSSA), using 13 MRSA and 7 MSSA strains isolated from clinical specimens. The infectivity and lethality of the two groups were examined as to the inoculum required to infect 50% of guinea pigs (ID₅₀) and to kill 50% of mice (LD₅₀), respectively. The mean ID₅₀ [log₁₀ colony forming units (CFU)] for MRSA strains was 7.1 ± 0.60 standard deviation, which was 1.5 higher than that for MSSA strains (P < 0.001). The mean LD₅₀ (log₁₀ CFU) for MRSA strains was 9.0 ± 0.42, being 1.1 higher than that for MSSA strains (P = 0.001). Pretreatment of mice with cyclophosphamide decreased the mean LD₅₀ for MRSA strains more than that for MSSA strains, resulting in the difference in the mean LD₅₀ being insignificant (P = 0.502). These results indicate that MRSA is less virulent than MSSA in normal hosts, but that they are equally virulent in immunocompromised hosts. The growth of MRSA strains was much slower than that of MSSA strains in the lag phase, although their growth rates were almost the same in the exponential growth phase, suggesting that the difference in virulence between them may be at least partly due to such a difference in growth.     

Severity of respiratory signs and symptoms and virus profiles in Japanese children with acute respiratory illness

Associations between the severity of respiratory signs and symptoms and the respiratory viruses identified in 214 Japanese children with acute respiratory illness (ARI) enrolled between January and December 2012 were studied. Respiratory rate, wheezing, cyanosis, and the use of accessory muscles were used as indices of respiratory severity and phylogenetic analysis of the viruses identified in these children was performed. Respiratory viruses such as respiratory syncytial virus (RSV), human rhinovirus (HRV), human parainfluenza virus (HPIV), and human metapneumovirus (HMPV) were prevalent, being detected in approximately 70% of the patients (151/214 patients). Co‐detection of viruses occurred in about 9% of patients. RSV was identified more frequently in cases scored as moderate/severe than in those scored as mild (P < 0.05). Severity scores of patients with RSV were significantly higher than those of cases with HPIV. Moreover, severity scores in patients with mild disease and co‐detections were higher than in those in whom only HPIV or adenovirus was detected. Phylogenetic analysis showed that many genotypes of HRV‐A and ‐C with wide genetic divergence were associated with acute respiratory illness (ARI). On the other hand, only a limited number of genotypes of RSV were associated with ARI. HPIV and HMPV were associated with ARI at similar frequencies. These results suggest that different respiratory viruses with unique genetic characteristics can be found in patients with mild to severe ARI.     

Assessment of adenovirus,hepatitis A virus and rotavirus presence in environmental samples in Florianopolis,South Brazil

Aims: To assess the presence of human adenovirus (HAdV), hepatitis A (HAV) virus and rotavirus A (RV‐A) in environmental samples from the Southern region of Brazil and to provide viral contamination data for further epidemiological studies and governmental actions. Methods and Results: Water samples from various sources (seawater, lagoon brackish water, urban wastewater, drinking water sources‐with and without chlorination and water derived from a polluted creek) and oysters of two growing areas were analysed by enzymatic amplification (nested PCR and RT‐PCR), quantification of HAdV genome (qPCR) and viral viability assay by integrated cell culture‐PCR (ICC‐PCR). From June 2007 to May 2008 in a total of 84 water samples, 54 (64·2%) were positive for HAdV, 16 (19%) for RV‐A and 7 (8·3%) for HAV. Viability assays showed nonpositive samples for HAV; though, infectious viruses were confirmed for RV‐A (12·5%) and HAdV (88·8%). Oyster samples by PCR were positive for HAdV (87·5%) and RV‐A (8·3%), but none for HAV. Quantitative PCR in oysters showed means loads in genomic copies (gc) of 9·1 × 10⁴ gc g^?1 (oyster farm south) and 1·5 × 10⁵ gc g^?1 (oyster farm north) and in waters ranging from 2·16 × 10⁶ (lagoon water) to 1·33 × 10⁷ gc l^?1 (untreated drinking water). Conclusions: This study has shown a widespread distribution of the analysed viruses in this particular region with high loads of HAdV in the environment which suggests the relevance of evaluating these viruses as positive indicators of viral contamination of water. Significance and Impact of the Study: The environmental approach in this study provides data concerning the prevalence, viability and quantification of enteric viruses in environmental waters and oysters in the South region of Brazil and has indicated that their presence might pose a risk to population in contact with the environmental samples searched.     

Identification of a casein kinase II phosphorylation domain in NS1 protein of H5N1 influenza virus

Influenza virus causes febrile respiratory illness. The infection results in significant mortality, morbidity and economic disruption. In this bioinformatics study, we used the NS1 (the conserved nonstructural) protein of influenza A virus to demonstrate its role in infectivity. Our in silico study revealed a new Casein kinase II (CKII) phosphorylation domain at position 151-154. This domain was formed due to the mutation at position 151 (T151I). Moreover, considerable difference in the secondary structure of this protein due to mutation was also reported. It is also confirmed by contact residue analysis that the changes in secondary structure are due to mutations.     

Genomics-based re-examination of the taxonomy and phylogeny of human and simian Mastadenoviruses: an evolving whole genomes approach,revealing putative zoonosis,anthroponosis, and amphizoonosis

With the advent of high-resolution and cost-effective genomics and bioinformatics tools and methods contributing to a large database of both human (HAdV) and simian (SAdV) adenoviruses, a genomics-based re-evaluation of their taxonomy is warranted. Interest in these particular adenoviruses is growing in part due to the applications of both in gene transfer protocols, including gene therapy and vaccines, as well in oncolytic protocols. In particular, the re-evaluation of SAdVs as appropriate vectors in humans is important as zoonosis precludes the assumption that human immune system may be naïve to these vectors. Additionally, as important pathogens, adenoviruses are a model organism system for understanding viral pathogen emergence through zoonosis and anthroponosis, particularly among the primate species, along with recombination, host adaptation, and selection, as evidenced by one long-standing human respiratory pathogen HAdV-4 and a recent re-evaluation of another, HAdV-76. The latter reflects the insights on amphizoonosis, defined as infections in both directions among host species including “other than human”, that are possible with the growing database of nonhuman adenovirus genomes. HAdV-76 is a recombinant that has been isolated from human, chimpanzee, and bonobo hosts. On-going and potential impacts of adenoviruses on public health and translational medicine drive this evaluation of 174 whole genome sequences from HAdVs and SAdVs archived in GenBank. The conclusion is that rather than separate HAdV and SAdV phylogenetic lineages, a single, intertwined tree is observed with all HAdVs and SAdVs forming mixed clades. Therefore, a single designation of “primate adenovirus” (PrAdV) superseding either HAdV and SAdV is proposed, or alternatively, keeping HAdV for human adenovirus but expanding the SAdV nomenclature officially to include host species identification as in ChAdV for chimpanzee adenovirus, GoAdV for gorilla adenovirus, BoAdV for bonobo adenovirus, and ad libitum.     

Within‐host interactions shape virulence‐related traits of trematode genotypes

Within‐host interactions between co‐infecting parasites can significantly influence the evolution of key parasite traits, such as virulence (pathogenicity of infection). The type of interaction is expected to predict the direction of selection, with antagonistic interactions favouring more virulent genotypes and synergistic interactions less virulent genotypes. Recently, it has been suggested that virulence can further be affected by the genetic identity of co‐infecting partners (G × G interactions), complicating predictions on disease dynamics. Here, we used a natural host–parasite system including a fish host and a trematode parasite to study the effects of G × G interactions on infection virulence. We exposed rainbow trout (Oncorhynchus mykiss) either to single genotypes or to mixtures of two genotypes of the eye fluke Diplostomum pseudospathaceum and estimated parasite infectivity (linearly related to pathogenicity of infection, measured as coverage of eye cataracts) and relative cataract coverage (controlled for infectivity). We found that both traits were associated with complex G × G interactions, including both increases and decreases from single infection to co‐infection, depending on the genotype combination. In particular, combinations where both genotypes had low average infectivity and relative cataract coverage in single infections benefited from co‐infection, while the pattern was opposite for genotypes with higher performance. Together, our results show that infection outcomes vary considerably between single and co‐infections and with the genetic identity of the co‐infecting parasites. This can result in variation in parasite fitness and consequently impact evolutionary dynamics of host–parasite interactions.