Molecular Typing of Human Adenovirus Infection among Hospitalized Patients with Respiratory Tract Infections in Guangzhou, China

doi:10.21203/rs.3.rs-401554/v1

Background Human Adenoviruses (HAdVs) cause a wide array of illnesses in all age groups. They particularly cause frequent morbidity among children. In China, human adenovirus types 3, 4, 7, 11, 14, 21, and 55 have caused at least seven outbreaks since 2000. However, limited studies are available regarding the epidemiological patterns and diversity of HAdVs types among hospitalized patients with respiratory tract infections (RTIs).

Methods To understand the epidemiology and type distribution of HAdV infections associated with RTIs in China, nasal swab (NS) clinical samples were collected from 4129 patients in a Guangzhou hospital between August 2017 and October 2019. PCR, sequencing, and phylogenetic analysis were performed on these specimens to identify HAdV virus types.

Results HAdV was detected in 99 (2.4%) of the 4,129 NS specimens, with the highest HAdV prevalence (6.3%) found in children between the ages of 5 and 10 years. Among HAdV-positive specimens, the most prevalent genotypes identified were HAdV-B3 (55.6%) and HAdV-B7 (25.3%). The most common symptoms in the HAdV-infected patients were fever (100%), cough (80.8%) and rhinorrhea (71.8%). HAdV infections were detected throughout the year with a relatively higher prevalence in summer.

Conclusion All ages suffer adenovirus infections, but young children are at greatest risk. These study data demonstrate that at least three species of HAdVs (species B, C, and E) are circulating in Guangzhou City, China. As antiviral therapies and type-specific vaccines become available, such epidemiological data will be useful in guiding therapy and public health interventions.

Infectious Diseases

adenovirus

PCR

genotyping molecular epidemiology

respiratory diseases

Human adenoviruses (HAdV) are non-enveloped double-stranded DNA viruses. They belong to the family Adenoviridae. Approximately 103 subtypes of HAdV have been documented to date. They are organized into seven species (A-G) [1, 2]. HAdV is a highly contagious pathogen that causes various clinical illnesses, including upper and lower respiratory infections, bronchitis, pneumonia, conjunctivitis, and acute gastroenteritis [3]. All age groups of people are susceptible to HAdV infections, while children, immunocompromised patients, cardiovascular disease patients, and military trainees are at a higher risk for developing severe disease [3–5]. It has been reported that HAdV is responsible for at least 5–10% of pediatric and 1–7% of adult respiratory tract infections (RTIs) [6]. HAdV infections have a worldwide distribution, but the distribution of adenovirus types often differs by geographical region or human population. Among all HAdVs, type 3, 4, 7, 14, 21, and 55 often cause severe infections and have been linked to outbreaks globally [7–11]. HAdV-associated outbreaks are more likely to occur in closed and crowded conditions, such as schools, hospitals, or military recruits [7, 9].

In recent years, an increasing number of HAdV outbreaks have been reported in China. An acute respiratory infection (ARI) outbreak caused by a re-emergent isolate of HAdV55 occurred in Shanxi Province in 2006 [12]. An outbreak of febrile respiratory illness caused by HAdV-14p1 occurred in Gansu Province in 2011 [13]. Two outbreaks of acute respiratory diseases caused by HAdV-7 were detected in military training camps, one in Hubei Province and another in Shaanxi Province between 2012 and 2013 [7]. HAdV-B3 was also frequently reported as the common cause of epidemic ARI outbreaks in China [14]. However, limited data are available regarding the epidemiological and clinical features of HAdV in hospitalized patients. This study we sought to determine the prevalence and types of HAdVs among hospitalized patients with RTIs in Guangzhou, China. Such epidemiological data are useful to health professionals regarding decisions in employing appropriate therapy and adopting effective prevention strategies for adenovirus control.

Case Definition

A total of 4,129 nasal swab (NS) specimens were previously collected from patients with RTIs at the Second Affiliated Hospital of Guangzhou University of Chinese Medicine between August 2017 and October 2019. These patients were recruited for participation in the hospital’s study if they met the following inclusion criteria: (i) had a fever (temperature ≥ 37.3°C, measured at the hospital) with the apparent respiratory symptom(s); (ii) did not have the bacterial infection (white blood cell count > 12x109/L, or PCT > 0.5ng/L). Individuals who met the inclusion criteria were consented (parental consent required for adolescents under the age of 18) and invited to complete a brief questionnaire about their demographics and symptoms.

Subject Sample Collection

Each participant permitted the collection of one NS specimen (the swab stayed in the nose for 15 seconds), which was placed in viral transport media (COPAN Diagnostics Inc, Italy), stored in the icebox and then transported to the hospital’s laboratory. Specimens were preserved at -80°C until further processing.

At the hospital’s laboratory, all clinical NS specimens were first screened with the commercially available Immunofluorescence assay (respiratory viral panel 1 screening and identification kit, Light DiagnosticTM, Chemicon International Inc, Temecula, USA) targeting adenovirus, influenza A and B virus, parainfluenza 1–3, and respiratory syncytial virus (RSV). A total of 117 HAdV-positive specimens were detected. Later these HAdV-positive specimens were sent to the Duke Kunshan University (DKU) One Health Research Laboratory for further study.

Detection of HAdV with Real-Time PCR

At the DKU One Health Research Laboratory, DNA was extracted from HAdV-positive specimens and eluted in 60µl of elution buffer using a QIAamp MinElute Virus Spin Kit (Cat. No.57704, Qiagen Inc., Hilden, Germany). Extracted DNA was then tested for adenovirus by real-time reverse transcriptase-polymerase chain reaction (qPCR) assays using a BioRad SsoAdvanced Universal Probes Supermix (Bio-Rad Laboratories, Richmond, CA) as previously described [15] on a Mic qPCR Cycler (BioMolecular Systems, EI Cajon, CA). Positive and negative template controls were included in each qPCR run. The qPCR cycling was run as follows: 90°C for 2 min, 95°C for 3 min, followed by 40 cycles of 95°C for 15s, and 60°C for 30s. Samples with quantification cycles (Cq) values < 38 were considered positive for adenovirus.

Nested PCR targeting the HAdV hexon gene’s hyper-variable regions 1–6 (HVR1-6) was performed for genotyping (predicted amplicon size: 764–896 base pairs (bp) [16]. The outer primers used in the first-round amplification were AdhexF1 (5’-TGTAAAACGACGGCCAGT-TICTTTGACATICGIGGIGTICTIGA-3’) and AdhexR1 (5’-CTGTCIACIGCCTGRTTCCACA-3’). The inner primers used in a second PCR were AdhexF2 (5’-GGYCCYAGYTTYAARCCCTAYTC-3’) and AdhexR2 (5’-GGTTCTGTCICCCAGAGARTCIAGCA-3’). Nested PCR was conducted in a 50µl volume comprising 5µl of 10 * EXTaq buffer, 0.2µl (50µM) of each primer, 1.0µl of dNTP Mix, 1.5µl of 50mM MgCI2, 0.2µl of Taq DNA Polymerase, 0.5µl of first nested-PCR product, and 41.4µl of double-distilled water. Cycling conditions were employed as follows: 94°C for 2 minutes, followed by 36 cycles at 94°C for 1 min, 45°C for 1 min, and 72°C for 2 min, and a 5 min extension at 72°C. PCR products were analyzed on 2% agarose gels and sent for sequencing.

Sequence and Phylogenetic Analysis

Hexon gene nucleotide sequences from the specimens collected in this study were aligned with multiple reference strains available in GenBank (Supplementary Table 1) using ClustalW. The phylogenetic tree was constructed by the neighbor-joining method with bootstrap analysis (n = 1,000) by MEGA7.0 software.

Statistical Analysis

STATA version 15.0 (StataCorp LP, College Station, TX) was used for statistically analysis. Chi-square or Fisher’s exact tests were used to examine risk factor associations with HAdV molecular detections

Demographic Data of the Hospitalized Patients

The 99 HAdV-positive pateints identified in this study included 66 (63.67%) males and 33 (33.33%) females. Their median age was 4 years, range 2 months to 63 years. The HAdV-positive patients were distributed across age groups: Age groups <5, 5-10, 10-19, and ≥19 years, accounted for 3.8%, 6.3%, 0.6%, 0.16% of positives, respectively (Table 1). A significant difference in the number of HAdV-positive patients among the different age groups was observed with the highest prevalence of HAdV infections being found among children who were between 5 and 10 years (6.3%), followed by those under five years (3.8%). There was no significant difference in HAdV-positivity observed between males and females.

Clinical Feature of HAdV-Infected Patients

Among 99 HAdV-positive patients, two patients had missing clinical information and were not included in Table 2. Clinical diagnosis included pneumonia (38.1%), acute bronchitis (24.7%), acute upper respiratory tract infections (AURTI) (17.5%), acute tonsillitis (3.2%), and gastroenteritis (4.1%). It is worth noting that approximately 79% of pneumonia patients were found among children under ten years in age. The most prevalent clinical signs were fever (99.0%), cough (82.5%), rhinorrhea (69.1%), and expectoration (62.9%), while the other clinical presentation were sore throat (19.6%) and diarrhea (8.2%). No HAdV-associated deaths were reported.

Seasonal Distribution of the HAdV Infections

In China, 12 months were classified into four seasons, including Spring (March to May), Summer (June to August), Autumn (September to November), and Winter (December to February). The number of HAdV-positive patients from August 2017 to October 2019 detected in different seasons are depicted in Figure 1. HAdV infections were detected during each season. However, the highest numbers of HAdV positive patients were found in the summer in both 2018 and 2019 with 22 and 17 HAdV patients, respectively.

Molecular Characterization of HAdV

qPCR Results

Among the 117 immunofluorescence-positive HAdV specimens, 103 (88.0%) specimens were detected as HAdV-positive with qPCR at DKU One Health Research Laboratory.

Sequence and Phylogenetic Analysis

To further analyze the HAdV genotype, the hexon gene from 103 HAdV positive specimens was amplified by conventional PCR. Ninety-nine (96.1%) specimens were successfully genotyped. Eight out of 99 sequences selected as representative sequences (see details in supplementary material) were further aligned with other reference strains (partial Hexon gene) (Figure 2). The phylogenetic analysis indicated that 84 patients belonged to species B, 7 patients belonged to species C, and 8 patients belonged to species E (Table 3). Within the HAdV-B species, type 3, 7, and 55 were identified. It is worth noting that all the HAdV-B strains identified in this study were highly identical to strains detected in Shenzhen and Jiangxi City, suggesting the genetic conservation of some HAdV-B viruses in different areas of China. Additionally, HAdV-B3 and HAdV-B7 were the most prevalent types in this study. Within the HAdV-C species, types 1, 2 and 5 were identified. All the HAdV-C species generated from this study seem to be more closely related to HAdV-C viruses circulated in neighboring countries. For example, the HAdV-C1 strain in this study was nearly identical to the strain CAU230/AdV/KOR/2016 found in South Korea. The HAdV-C5 strain identified in this study was identical to a Japanese HAdV virus. Study findings indicated that Species B, C, and E (at least seven subtypes) circulated simultaneously in Guangzhou in 2017-2019.

Clinical Characteristics of HAdV Genotypes

HAdV genotypes differed in their characteristics (Table 3). The most common clinical manifestations of all HAdV genotypes were fever (100%), cough (50 - 100%), and rhinorrhea (50-100%). The comparison among the seven HAdV types revealed that HAdV-B7 caused more severe diarrhea than other HAdV types. The majority (94.6%) of pneumonia patients were found to be associated with HAdV-B species (including type 3, 7, and 55). Unexpectedly, three out of four gastroenteritis patients were found in patients who were infected with HAdV-B7.

A recent multicenter, prospective registry study found that adenovirus was the third-leading cause of viral infection among community-acquired pneumonia (CAP) patients in China, after influenza viruses and respiratory syncytial virus [17]. An increasing number of HAdV outbreaks have been reported in China in recent years [7, 12, 14, 18]. But because there is no national surveillance system for HAdV in China and there is often no difference in symptom clustering between viral and bacterial infections, the diagnosis of HAdV is often underestimated [2].

The present study recorded the epidemiological distribution of circulating HAdV strains among hospitalized patients with respiratory tract infections (RTIs) between 2017 and 2019 in Guangzhou City, China. In this study, the overall positive rate of HAdV was 2.4%, which is consistent with the positive rate (2.0%-6.1%) found in hospitalized patients with acute viral respiratory infection in other recent reports [3, 19–21]. However, two previous studies conducted in the Northern part of China showed a higher HAdV prevalence (10.4%-20.1%) than our study [22, 23]. These findings demonstrate that HAdV prevalence may differ by geographic locations. Such differences in HAdV prevalence could be influenced by a number of factors, including sample type, small sample size, sampling period, study duration, and patients’ demographic information.

Regarding patient demographic data, there was no significant difference observed in HAdV detections between genders in this study. This is consistent with the findings of previous studies conducted in China [3, 20]. However, this was in contrast to some previous reports that male children were more likely to be infected with HAdV [24, 25]. The highest HAdV-positive rate was observed among children between the ages of 5 and 10 years, which is similar to the findings of a recent study in the same city [3]. However, most previous reports found that the HAdV infections occurred more often among children under five years of age [19, 26–28].

Our study revealed that although HAdV infections were detected throughout the year, the prevalence peaked in the summer. This is consistent with findings of Chen et al [28] during 2012–2013. But it was not consistent with that of studies conducted in Northern China [22] and Mexico [29]. In Tanzania and Switzerland, HAdV infections were observed during all seasons of the year with no clear seasonality demonstrated [21, 27]. These difference in HAdV prevalence between seasons are interesting and bear future study as seasonal risk could influence future employment of HAdV vaccines which are in development in China [30].

In this study, seven HAdV types were identified: HAdV-B3, HAdV-B7, HAdV-B55, HAdV-C1, HAdV-C2, HAdV-C5, and HAdV-E4. Among these types, HAdV-B3 and HAdV-B7 were most prevalent which is consistent with other reports in Asia [26, 31, 32].

The majority (94.6%) of HAdV types detected in this study were of species B. HAdV-B (e.g., 3, 7, and 55) has been continuously reported to be associated with more severe acute respiratory disease than other HAdVs species [2, 14, 18]. Only seven patients were found to have HAdV-C and only eight patients were found to have HAdV-E infection during the study period.

Previously, three types of HAdV-C (e.g., 1, 2, and 5) were identified in China, although studies of HAdV-C species have been limited [33]. HAdV-C species viruses were identified as the primary pathogens responsible for respiratory tract infections among hospitalized children, particularly among infants under two years of age [33]. Our study is consistent with this in that more than half of HAdV-C-positive patients were observed in children less than two years old. Previous research suggests that recombination events are commonly observed among HAdV-C types [33]. As recombinant HAdV strains have caused epidemics, it seems prudent to monitor for changes in HAdV-C types in China.

Although our study provides crucial molecular evidence regarding the epidemiology and clinical features of HAdV infections in Guangzhou, China, it has several limitations. First, we did not study outpatients and they could have had a different distribution of HAdV types. Second, study samples were first identified using a commercial assay which is not thought to be as sensitive as the qPCR we employed. Hence, we likely only captured data on the specimens with higher viral titers. Thus, the true prevalence of HAdV among hospitalized patients may have been higher and the distribution of HAdV types different. Third, we were unable to rule out a number of possible viral coinfections that were not surveilled for with the commercial product (e.g., parainfluenza 4, rhinoviruses, enteroviruses, etc.). Hence, some of the clinical findings we observed could be due coinfections with viruses other HAdV.

At present, there are no specific antiviral drugs or vaccine available in China for the treatment or prevention of HAdV infections. However, effective antivirals [34, 35] and vaccines [30, 36] seem to be on the near horizon. Hence, conducting type-specific surveillance for HAdV is an important need for China. Nationwide, periodic HAdV surveillance could alert Chinese public health officials of the emergence of pre-pandemic or particularly virulent strains and help them mitigate the threat. For instance, currently, there seems to be a worldwide increase in the threat of HAdV type four which could be mitigated with the Teva, Inc. HAdV four live vaccine [37].

Ethics Statement

This study was approved by the Ethics Committee of The Second Affiliated Hospital of Guangzhou University of Chinese Medicine (Reference B2017-032-01). Individual written informed consent was obtained from the patients or patients’ parents or guardians.

Acknowledgements

This study was supported by funding from The Second Affiliated Hospital of Guangzhou University of Chinese Medicine. Funding included the specific research fund for TCM Science and technology of Guangdong Provincial Hospital of Chinese Medicine (No. YN2015MS09 and YN2016QN10) and major national science and technology projects (2017ZX10305501-006). We thank many professionals who collected the achieved human specimens.

Conflict of Interest

The authors declare that they have no conflicts of interest.

Author Contribution

X.W. conducted laboratory analysis and drafted the manuscript. D.W attended to filed work and revised the manuscript. S.U. guided the work and revised the manuscript. Q.S. and L.Q. identified the HAdV positive specimens using immunofluorescence assays and collected clinical information from patients. Y.L guided the field work in Guangzhou and attended to draft the manuscript. G.C.C conceived the study, guided the work, and revised the manuscript.

Dhingra A, Hage E, Ganzenmueller T, Böttcher S, Hofmann J, Hamprecht K, Obermeier P, Rath B, Hausmann F, Dobner T et al: Molecular Evolution of Human Adenovirus (HAdV) Species C. Sci Rep 2019, 9(1):1039.
Cai R, Mao N, Dai J, Xiang X, Xu J, Ma Y, Li Z, Han G, Yu D, Yin J et al: Genetic variability of human adenovirus type 7 circulating in mainland China. PLoS One 2020, 15(4):e0232092.
Zou L, Yi L, Yu J, Song Y, Liang L, Guo Q, Zhuang X, Zhang Y, Kang M, Wu J: Adenovirus infection in children hospitalized with pneumonia in Guangzhou, China. Influenza Other Respir Viruses 2021, 15(1):27-33.
Kolavic-Gray SA, Binn LN, Sanchez JL, Cersovsky SB, Polyak CS, Mitchell-Raymundo F, Asher LV, Vaughn DW, Feighner BH, Innis BL: Large epidemic of adenovirus type 4 infection among military trainees: epidemiological, clinical, and laboratory studies. Clinical infectious diseases : an official publication of the Infectious Diseases Society of America 2002, 35(7):808-818.
Lion T: Adenovirus infections in immunocompetent and immunocompromised patients. Clin Microbiol Rev 2014, 27(3):441-462.
Lynch JP, 3rd, Kajon AE: Adenovirus: Epidemiology, Global Spread of Novel Serotypes, and Advances in Treatment and Prevention. Semin Respir Crit Care Med 2016, 37(4):586-602.
Yu P, Ma C, Nawaz M, Han L, Zhang J, Du Q, Zhang L, Feng Q, Wang J, Xu J: Outbreak of acute respiratory disease caused by human adenovirus type 7 in a military training camp in Shaanxi, China. Microbiol Immunol 2013, 57(8):553-560.
Rebelo-de-Andrade H, Pereira C, Gíria M, Prudêncio E, Brito MJ, Calé E, Taveira N: Outbreak of acute respiratory infection among infants in Lisbon, Portugal, caused by human adenovirus serotype 3 and a new 7/3 recombinant strain. J Clin Microbiol 2010, 48(4):1391-1396.
Salama M, Amitai Z, Amir N, Gottesman-Yekutieli T, Sherbany H, Drori Y, Mendelson E, Carmeli Y, Mandelboim M: Outbreak of adenovirus type 55 infection in Israel. Journal of clinical virology : the official publication of the Pan American Society for Clinical Virology 2016, 78:31-35.
Philo SE, Anderson BD, Costa SF, Henshaw N, Lewis SS, Reynolds JM, Jayakumar J, Su YCF, Gray GC: Adenovirus Type 21 Outbreak Among Lung Transplant Patients at a Large Tertiary Care Hospital. Open Forum Infect Dis 2018, 5(8):ofy188.
Gray GC, Chorazy ML: Human adenovirus 14a: a new epidemic threat. J Infect Dis 2009, 199(10):1413-1415.
Zhu Z, Zhang Y, Xu S, Yu P, Tian X, Wang L, Liu Z, Tang L, Mao N, Ji Y et al: Outbreak of acute respiratory disease in China caused by B2 species of adenovirus type 11. J Clin Microbiol 2009, 47(3):697-703.
Huang G, Yu D, Zhu Z, Zhao H, Wang P, Gray GC, Meng L, Xu W: Outbreak of febrile respiratory illness associated with human adenovirus type 14p1 in Gansu Province, China. Influenza Other Respir Viruses 2013, 7(6):1048-1054.
Xie L, Yu XF, Sun Z, Yang XH, Huang RJ, Wang J, Yu A, Zheng L, Yu MC, Hu XW et al: Two adenovirus serotype 3 outbreaks associated with febrile respiratory disease and pharyngoconjunctival fever in children under 15 years of age in Hangzhou, China, during 2011. J Clin Microbiol 2012, 50(6):1879-1888.
Yadana S, Coleman KK, Nguyen TT, Hansen-Estruch C, Kalimuddin S, Thoon KC, Low JGH, Gray GC: Monitoring for airborne respiratory viruses in a general pediatric ward in Singapore. Journal of public health research 2019, 8(3):1407.
Lu X, Erdman DD: Molecular typing of human adenoviruses by PCR and sequencing of a partial region of the hexon gene. Arch Virol 2006, 151(8):1587-1602.
Zhou F, Wang Y, Liu Y, Liu X, Gu L, Zhang X, Pu Z, Yang G, Liu B, Nie Q et al: Disease severity and clinical outcomes of community-acquired pneumonia caused by non-influenza respiratory viruses in adults: a multicentre prospective registry study from the CAP-China Network. Eur Respir J 2019, 54(2).
Lu G, Peng X, Li R, Liu Y, Wu Z, Wang X, Zhang D, Zhao J, Sun Y, Zhang L et al: An outbreak of acute respiratory infection at a training base in Beijing, China due to human adenovirus type B55. BMC infectious diseases 2020, 20(1):537.
Wen S, Lin Z, Zhang Y, Lv F, Li H, Zhang X, Lin L, Zhu HH, Xu Z, Li C et al: The Epidemiology, Molecular, and Clinical of Human Adenoviruses in Children Hospitalized With Acute Respiratory Infections. Front Microbiol 2021, 12:629971.
Yao LH, Wang C, Wei TL, Wang H, Ma FL, Zheng LS: Human adenovirus among hospitalized children with respiratory tract infections in Beijing, China, 2017-2018. Virol J 2019, 16(1):78.
Akello JO, Kamgang R, Barbani MT, Suter-Riniker F, Leib SL, Ramette A: Epidemiology of Human Adenoviruses: A 20-Year Retrospective Observational Study in Hospitalized Patients in Bern, Switzerland. Clin Epidemiol 2020, 12:353-366.
Li Y, Zhou W, Zhao Y, Wang Y, Xie Z, Lou Y, Tan W: Molecular typing and epidemiology profiles of human adenovirus infection among paediatric patients with severe acute respiratory infection in China. PLoS One 2015, 10(4):e0123234.
Liu CY, Xiao Y, Xie ZD, Ren LL, Hu YH, Yao Y, Yang Y, Qian SY, Zhao CS, Shen KL: [Viral etiology of acute respiratory tract infection among pediatric inpatients and outpatients from 2010 to 2012 in Beijing, China]. Zhonghua Er Ke Za Zhi 2013, 51(4):255-259.
Liu C, Xiao Y, Zhang J, Ren L, Li J, Xie Z, Xu B, Yang Y, Qian S, Wang J et al: Adenovirus infection in children with acute lower respiratory tract infections in Beijing, China, 2007 to 2012. BMC infectious diseases 2015, 15:408.
Li L, Woo YY, de Bruyne JA, Nathan AM, Kee SY, Chan YF, Chiam CW, Eg KP, Thavagnanam S, Sam IC: Epidemiology, clinical presentation and respiratory sequelae of adenovirus pneumonia in children in Kuala Lumpur, Malaysia. PLoS One 2018, 13(10):e0205795.
Wang H, Zheng Y, Deng J, Chen X, Liu P, Li X: Molecular epidemiology of respiratory adenovirus detection in hospitalized children in Shenzhen, China. Int J Clin Exp Med 2015, 8(9):15011-15017.
Moyo SJ, Hanevik K, Blomberg B, Kommedal O, Nordbø SA, Maselle S, Langeland N: Prevalence and molecular characterisation of human adenovirus in diarrhoeic children in Tanzania; a case control study. BMC infectious diseases 2014, 14:666.
Chen Y, Liu F, Wang C, Zhao M, Deng L, Zhong J, Zhang Y, Ye J, Jing S, Cheng Z et al: Molecular Identification and Epidemiological Features of Human Adenoviruses Associated with Acute Respiratory Infections in Hospitalized Children in Southern China, 2012-2013. PLoS One 2016, 11(5):e0155412.
Rosete DP, Manjarrez ME, Barrón BL: Adenoviruses C in non-hospitalized Mexican children older than five years of age with acute respiratory infection. Mem Inst Oswaldo Cruz 2008, 103(2):195-200.
Tian X, Jiang Z, Fan Y, Qiu S, Zhang L, Li X, Zhou Z, Liu T, Ma Q, Lu X et al: A tetravalent vaccine comprising hexon-chimeric adenoviruses elicits balanced protective immunity against human adenovirus types 3, 7, 14 and 55. Antiviral Res 2018, 154:17-25.
Sriwanna P, Chieochansin T, Vuthitanachot C, Vuthitanachot V, Theamboonlers A, Poovorawan Y: Molecular characterization of human adenovirus infection in Thailand, 2009-2012. Virol J 2013, 10:193.
Coleman KK, Wong CC, Jayakumar J, Nguyen TT, Wong AWL, Yadana S, Thoon KC, Chan KP, Low JG, Kalimuddin S et al: Adenoviral Infections in Singapore: Should New Antiviral Therapies and Vaccines Be Adopted? J Infect Dis 2020, 221(4):566-577.
Yang J, Mao N, Zhang C, Ren B, Li H, Li N, Chen J, Zhang R, Li H, Zhu Z et al: Human adenovirus species C recombinant virus continuously circulated in China. Sci Rep 2019, 9(1):9781.
Florescu DF, Keck MA: Development of CMX001 (Brincidofovir) for the treatment of serious diseases or conditions caused by dsDNA viruses. Expert Rev Anti Infect Ther 2014, 12(10):1171-1178.
Sandkovsky U, Vargas L, Florescu DF: Adenovirus: current epidemiology and emerging approaches to prevention and treatment. Curr Infect Dis Rep 2014, 16(8):416.
Liu T, Zhou Z, Tian X, Liu W, Xu D, Fan Y, Liao J, Gu S, Li X, Zhou R: A recombinant trivalent vaccine candidate against human adenovirus types 3, 7, and 55. Vaccine 2018, 36(16):2199-2206.
Coleman KK, Robie ER, Abdelgadir A, Kozhumam AS, Binder RA, Gray GC: Six Decades of Human Adenovirus Type 4 Infections Reviewed: Increasing Infections Among Civilians Are a Matter of Concern. Clinical infectious diseases : an official publication of the Infectious Diseases Society of America 2021.

Table 1. Human adenovirus (HAdVs) infections among 99 patients hospitalized with respiratory tract infections in Guangzhou, China between August 2017 and October 2019. Patients were enrolled from the Second Affiliated Hospital of Guangzhou University of Chinese Medicine.

Characteristics	Number of Patients*	Number of patients positive for HAdVs	Percentage of patients positive for HAdV	P-value
Age (years)				0
<5 years	1485	57	3.80%
5 -<10 years	600	38	6.30%
10-<19 years	169	1	0.60%
≥19 years	1855	3	0.20%
Gender				0.107
Male	2416	66	2.70%
Female	1693	33	2.00%

Note: * Of the 4129 patients, 20 patients had information missing on age, gender, and clinical information, and were thus excluded from the analysis.

	Table 2. Clinical characteristics of patients who had adenovirus (HAdVs)-positive nasal swab specimens.
	Characteristics		HAdV positive (%) (N=97)
	Diagnosis
Pneumonia		37 (38.1)
Acute bronchitis		24 (24.7)
Acute tonsillitis		3 (3.2)
AURTI		17 (17.5)
Gastroenteritis		4 (4.1)
	Symptoms
	Fever		96 (99.0)
	Cough		80 (82.5)
	Rhinorrhea		67 (69.1)
	Expectoration		61 (62.9)
	Sore throat		19 (19.6)
	Diarrhea		8 (8.2)
	Prognosis
	Totally recovery		97 (100)
	Death		0 (0)

Table 3. Clinical and laboratory characteristics of patients who had a human adenovirus (HAdVs)-positive nasal swab specimen, by HAdV type.
Characteristics	*HAdV B3 (n=53)**	HAdV B7 (n=25)	HAdV B55 (n=4)	HAdV E4 (n=8)	HAdV C1 (n=2)	HAdV C2 (n=3)	HAdV C5 (n=2)
*Symptoms*
Fever	53 (100.0)	24 (100.0)	4 (100.0)	8 (100.0)	2 (100.0)	3 (100.0)	2 (100.0)
Cough	45 (84.9.4)	21 (84.0)	4 (100.0)	4 (50.0)	2 (100.0)	2 (66.7)	2 (100.0)
Rhinorrhea	38 (71.7)	15 (60.0)	4 (100.0)	6 (75.0)	1 (50.0)	2 (66.7)	2 (100.0)
Sore throat	9 (17.0)	5 (20.0)	1 (25.0)	3 (37.5)	1 (50.0)	0 (0.0)	0 (0.0)
Expectoration	36 (67.9)	13 (52.0)	3 (75.0)	3 (37.5)	2 (100.0)	2 (66.7)	2 (100.0)
Diarrhea	2(3.8)	5 (20.0.)	0 (0.0)	1 (12.5)	0 (0.0)	0 (0.0)	0 (0.0)
*Diagnosis*
Acute Tonsillitis	2 (3.8)	1 (4.0)	0 (0.0)	0 (0.0)	0 (0.0)	0 (0.0)	0 (0.0)
URTI	8 (15.1)	4 (15.0)	1 (25.0)	0 (0.0)	0 (0.0)	0 (0.0)	2 (100.0)
Acute Bronchitis	12 (22.6)	7 (28.0)	1 (25.0)	2 (25.0)	1 (50.0)	1 (33.3)	0 (0.0)
Pneumonia	21 (39.6)	12 (48)	2 (50.0)	1 (12.5)	1 (50.0)	0 (0.0)	0 (0.0)
Gastroenteritis	0 (0)	3 (12)	0 (0.0)	1 (12.5)	0 (0.0)	0 (0.0)	0 (0.0)

Notes: 1) The total number of HAdV-B3 positive specimens is 55, but two patients with information miss on clinical features were not described. 2) URTI (upper respiratory tract infection); HAdV (human adenovirus)

No competing interests reported.

BMCSupplementaryMaterialXWGCG202104.docx

Molecular Typing of Human Adenovirus Infection among Hospitalized Patients with Respiratory Tract Infections in Guangzhou, China

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Abstract

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Materials And Methods

Results

Discussion

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Status:

Journal Publication

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