Letters to the Editor
679
Saffold virus respiratory infection in children and immunocompromised patients in Spain
Dear Editor, Kobayashi and colleagues recently reported in this Journal the seroepidemiology of Saffold virus (SAFV) genotype 3 in Japan.1 Since SAFV was first isolated, a total of eleven genotypes have been described, with SAFV-2 and SAFV-3 the most prevalent, with worldwide impact. This human cardiovirus has been investigated in the respiratory specimens of children with respiratory disease, but clinical significance of the infection, remains unknown.2e6 We aimed to characterize SAFV in respiratory samples from the pediatric population and from immunosuppressed adults, to clarify its association with respiratory disease over a three-year period (2004e2006). We also studied the infection’s seasonal pattern and circulating genotypes to understand its epidemiology and prevalence in patients attended to our hospital in Madrid, Spain. For this purpose, we conducted a retrospective study at the University Hospital 12 de Octubre, and we included respiratory specimens from pediatric patients and immunosuppressed adults. The presence of influenza virus (A and B), respiratory syncytial virus (RSV), parainfluenza virus (1, 2 and 3) adenovirus (ADV) and picornavirus was investigated by culture methods (conventional cell culture and shell-vial, Monofluo Screen, Bio-Rad), and other respiratory viruses [bocavirus (hBoV) and metapneumovirus (hMPV)] were investigated by PCR techniques with specific primers target each pathogen.7,8 The genetic material was obtained from 140 mL of the sample (Qiamp viral RNA kit, Qiagen), and reverse transcription with random hexamers was performed. All samples were screened for SAFV with a real-time PCR that targeted the 50 -untranslated region (50 UTR),9 and SAFV genotyping was carried out using a nested PCR, and by sequencing parts of the viral protein 2 (VP2) region of the capsid gene.10 Genotypes were determined by comparing the divergence of each amplicon using various SAFV VP2 sequences previously submitted to GenBank via the neighborjoining tree building method.
Table 1 period.
We included a total of 1203 respiratory samples: 608 nasopharyngeal aspirates from 552 children and 595 nasopharyngeal swabs from 370 immunosuppressed adults. All patients showed signs or symptoms of respiratory tract infection. The median age of pediatric patients was 0.8 (Interquartile range [IR], 0.2e2.6) years, and 59.2% were male. Regarding adult patients, 70.2% suffered from a malignant hematological disease; 17.8% of patients were solid organ transplant recipients; 6% were patients with some type of solid tumor and the remaining 6% of patients were infected with HIV. The median age was 52.0 (IR: 18.0e84.0) years and 57.8% were men. The real-time PCR for SAFV was positive in 8 of 1203 respiratory specimens. All cases involved the pediatric population, resulting in a prevalence of 1.3% in children. SAFV was not found in immunosuppressed adults. Other respiratory viruses were identified in both cohorts (Table 1). Wang et al. conducted a study in Australia involving a total of 1215 respiratory specimens from patients aged from two days to 95 years old, but they did not include specific immunosuppressed hosts. The authors found a prevalence of 0.66%, which is lower than we report. However, they noted that 75% of the positive specimens were from children of two years of age or younger, resulting in a similar prevalence as ours.6 Ren et al. reported a lower prevalence in Beijing (0.5%),3 and Itagaki et al. found a 3.5% detection rate in nasopharyngeal specimens from children in Japan. They reported an epidemic pattern for a 4month period, with a peak in October 2009.4 We found that all the children infected with SAFV were healthy, with no underlying disease, except for a girl who had asthma. The median age was 2.8 (IR: 1.6e2.9) years and 75% were male. Six patients had upper respiratory tract infections with fever and two had pneumonia. Co-infection with other pathogens were detected in three children (2 with ADV and 1 with Streptococcus pneumoniae). All eight patients were admitted to the hospital and were discharged a few days later without complications. Dual infection with primary respiratory pathogens was also noted in several studies,3,4,6 and the role of SAFV as a primary agent of pathology in these cases is discussed. Although the proportion of positive specimens with SAFV is not too high, we can note that as with other respiratory viruses, SAFV might show seasonal pattern variations, with
Respiratory viruses detected in respiratory specimens from pediatric and immunosuppressed adults over a three-year
Pediatric (N Z 608) Adults (N Z 595)
Influenza A (%)
Influenza B (%)
RSV (%)
ADV (%)
Parainfluenza type-3 (%)
Picornavirus (%)a
hBoV (%)
hMPV (%)
SAFV (%)
21 (3.5)
17 (2.8)
84 (13.8)
18 (3.0)
16 (2.6)
12 (2.0)
26 (4.3)
17 (2.8)
8 (1.3)
9 (1.5)
9 (1.5)
8 (1.3)
1 (0.2)
10 (1.6)
1 (0.2)
9 (1.5)
5 (0.8)
0 (0)
Dual infection episodes detected in pediatric patients: five RSV þ hBoV, two ADV þ hMPV, one ADV þ parainfluenza-3, one hBoV þ hMPV, one picornavirus þ hBoV, and one RSV þ parainfluenza-3. SAFV co-infection with adenovirus was detected in two pediatric patients. Co-infection cases detected in adult patients: two influenza A þ picornavirus, one influenza B þ picornavirus and one RSV þ parainfuenza type-3 virus. a Eight isolates of Picornaviridae family were identified as members of Enterovirus genus.
680
Letters to the Editor
displacement between genotypes every year. The phylogenetic analysis showed three different genetic lineages of SAFV: five corresponded to genotype 2, two corresponded to genotype 3 and one corresponded to genotype 6. The seasonal distribution was noted, with a peak in May 2004, and a detection rate of 50% (4 out of 8 specimens): one belonged to SAFV-6 and the other three belonged to SAFV2. Between January 2005 and April 2005, two cases were detected, both SAFV type-3; and between November 2005 and April 2006, the last two infections were identified as genotype 2. We also observed that the genotype of SAFV does not seem to imply greater severity or a disposition to produce more co-infection with other viruses. Further studies are necessary to better understand the dynamic of SAFV infection in the respiratory tract. Our results suggest that SAFV is a rare cause of respiratory disease in children attended to the hospital, and coinfection with other pathogens is frequent. To our knowledge, this is the first study that includes immunosuppressed patients, and we did not find SAFV in this population. In light of our data, and the rest of the published literature, we do not consider SAFV to be a virus to look for in routine clinical practice in respiratory specimens. Consideration for SAFV in certain situations in which other primary agents have been ruled out might be appropriated.
Lineages of a Novel Saffold cardiovirus in humans. Emerg Infect Dis 2008;14(9):1398e405. €ttiger B, Banner J, Hoffmann T, Nielsen LP. 10. Nielsen AC, Bo Serious invasive saffold virus infections in children, 2009. Emerg Infect Dis 2012;18(1):7e12.
Acknowledgments
Absence of occult Hepatitis E virus infection among HIV immunosuppressed patients
This study was supported by a grant (MMA 2007-056) from n Mutua Madrilen ~a. the Fundacio
References 1. Kobayashi M, Tsukagoshi H, Ishioka T, Mizuta K, Noda M, Morita Y, et al. Seroepidemiology of Saffold cardiovirus (SAFV) genotype 3 in Japan. J Infect 2013;66(2):191e3. 2. Abed Y, Boivin G. New Saffold cardioviruses in 3 children, Canada. Emerg Infect Dis 2008;14(5):834e6. 3. Ren L, Gonzalez R, Xie Z, Xiao Y, Li Y, Liu C, et al. Saffold cardiovirus of 3 Lineages in children with respiratory tract infections, Beijing, China. Emerg Infect Dis 2010;16(7):1158e61. 4. Itagaki T, Abiko C, Aoki Y, Ikeda T, Mizuta K, Noda M, et al. Saffold cardiovirus infection in children associated with respiratory disease and its similarity to coxackievirus infection. Pediatr Infect Dis J 2011;30(8):680e3. 5. Tsukagoshi H, Masuda Y, Mizutani T, Mizuta K, Saitoh M, Morita Y, et al. Sequencing and phylogenetic analyses of saffold cardiovirus (SAFV) Genotype 3 isolates from children with upper respiratory infection in Gunma, Japan. Jpn J Infect Dis 2010;63:378e80. 6. Wang CYT, Greer RM, Delwart E, Sloots TP, Mackay IM. A newly designed real-time RT-PCR for SAFV detects SAFV-2 and SAFV-3 in the respiratory tracts of children during 2011. J Clin Virol 2012;55:173e6. 7. Peret T, Boivin G, Li Y, Couillard M, Humphrey C, Osterhaus A, et al. Characterization of human metapneumoviruses isolated from patients in North America. J Infect Dis 2002;185:1660e3. 8. Maggi F, Andreoli E, Pifferi M, Meschi S, Rocchi J, Bendinelli M. Human bocavirus in Italian patients with respiratory diseases. J Clin Virol 2007;38:321e5. €cker A, Almeida PS, 9. Drexler JF, Kleber de Bouza Luna L, Sto Medrano Ribeiro TC, Peterson N, et al. Circulation of 3
~as* Patricia Bran Monica Garcıa Columbiana Prieto Lola Folgueira Department of Clinical Microbiology, University Hospital 12 de Octubre, Avda. Cordoba s/n, 28041 Madrid, Spain *Corresponding author. Department of Clinical Microbiology, University Hospital 12 de Octubre, Avda. Cordoba s/n, 28041 Madrid, Spain. Tel./fax: þ34 917 792 416.
~as) E-mail address: [email protected] (P. Bran Accepted 14 November 2014
http://dx.doi.org/10.1016/j.jinf.2014.11.006 ª 2014 The British Infection Association. Published by Elsevier Ltd. All rights reserved.
We have recently published a high Hepatitis E virus (HEV) seroprevalence among HIV-infected patients.1 We found an HEV seroprevalence of 9.8% [95% CI: 8.02%e11.9%]. Among HEV seropositive patients in five RNA-HEV was amplified. HIV patients could lack or delay antibody production against several viral co-infections. Hepatitis C (HCV) and Hepatitis B (HBV) have been identified in immunosuppressed HIV-infected patients in whom hepatitis IgG/IgM was not detected.2,3 This situation has not been evaluated in the context of HEV infection, and no studies have been designed to examine this trend. One limitation of our study was that HEV-RNA was only tested in those patients with IgG/ IgM þ antibodies. Consequently, the HEV-RNA prevalence could be underestimated. Thus, we set up an study to evaluate the presence of RNA-HEV in HIV-infected patients with low CD4þ cell counts who did not have HEV antibodies. HIV type-I-infected patients with CD4þ total cell counts lower than 200 cells/mL attending the Infectious Diseases rdoba Unit of the Hospital Universitario Reina Sofıa de Co (Southern Spain) from September 2012 to September 2013 were included in this prospective transversal study. At the time of inclusion, patients underwent a clinical examination and routine hematological, biochemical, immunological and virological assessments. All patients were tested for HEV using ELISA for anti-HEV IgG (Wantai HEV-IgG ELISA; Beijing Wantai Biological Pharmacy Interpriseª LTD, Beijing, China) and anti-HEV IgM (Wantai HEV-IgM ELISA; Beijing Wantai Biological Pharmacy Interpriseª LTD, Beijing, China). Serum samples were stored at 80 C prior
679
Saffold virus respiratory infection in children and immunocompromised patients in Spain
Dear Editor, Kobayashi and colleagues recently reported in this Journal the seroepidemiology of Saffold virus (SAFV) genotype 3 in Japan.1 Since SAFV was first isolated, a total of eleven genotypes have been described, with SAFV-2 and SAFV-3 the most prevalent, with worldwide impact. This human cardiovirus has been investigated in the respiratory specimens of children with respiratory disease, but clinical significance of the infection, remains unknown.2e6 We aimed to characterize SAFV in respiratory samples from the pediatric population and from immunosuppressed adults, to clarify its association with respiratory disease over a three-year period (2004e2006). We also studied the infection’s seasonal pattern and circulating genotypes to understand its epidemiology and prevalence in patients attended to our hospital in Madrid, Spain. For this purpose, we conducted a retrospective study at the University Hospital 12 de Octubre, and we included respiratory specimens from pediatric patients and immunosuppressed adults. The presence of influenza virus (A and B), respiratory syncytial virus (RSV), parainfluenza virus (1, 2 and 3) adenovirus (ADV) and picornavirus was investigated by culture methods (conventional cell culture and shell-vial, Monofluo Screen, Bio-Rad), and other respiratory viruses [bocavirus (hBoV) and metapneumovirus (hMPV)] were investigated by PCR techniques with specific primers target each pathogen.7,8 The genetic material was obtained from 140 mL of the sample (Qiamp viral RNA kit, Qiagen), and reverse transcription with random hexamers was performed. All samples were screened for SAFV with a real-time PCR that targeted the 50 -untranslated region (50 UTR),9 and SAFV genotyping was carried out using a nested PCR, and by sequencing parts of the viral protein 2 (VP2) region of the capsid gene.10 Genotypes were determined by comparing the divergence of each amplicon using various SAFV VP2 sequences previously submitted to GenBank via the neighborjoining tree building method.
Table 1 period.
We included a total of 1203 respiratory samples: 608 nasopharyngeal aspirates from 552 children and 595 nasopharyngeal swabs from 370 immunosuppressed adults. All patients showed signs or symptoms of respiratory tract infection. The median age of pediatric patients was 0.8 (Interquartile range [IR], 0.2e2.6) years, and 59.2% were male. Regarding adult patients, 70.2% suffered from a malignant hematological disease; 17.8% of patients were solid organ transplant recipients; 6% were patients with some type of solid tumor and the remaining 6% of patients were infected with HIV. The median age was 52.0 (IR: 18.0e84.0) years and 57.8% were men. The real-time PCR for SAFV was positive in 8 of 1203 respiratory specimens. All cases involved the pediatric population, resulting in a prevalence of 1.3% in children. SAFV was not found in immunosuppressed adults. Other respiratory viruses were identified in both cohorts (Table 1). Wang et al. conducted a study in Australia involving a total of 1215 respiratory specimens from patients aged from two days to 95 years old, but they did not include specific immunosuppressed hosts. The authors found a prevalence of 0.66%, which is lower than we report. However, they noted that 75% of the positive specimens were from children of two years of age or younger, resulting in a similar prevalence as ours.6 Ren et al. reported a lower prevalence in Beijing (0.5%),3 and Itagaki et al. found a 3.5% detection rate in nasopharyngeal specimens from children in Japan. They reported an epidemic pattern for a 4month period, with a peak in October 2009.4 We found that all the children infected with SAFV were healthy, with no underlying disease, except for a girl who had asthma. The median age was 2.8 (IR: 1.6e2.9) years and 75% were male. Six patients had upper respiratory tract infections with fever and two had pneumonia. Co-infection with other pathogens were detected in three children (2 with ADV and 1 with Streptococcus pneumoniae). All eight patients were admitted to the hospital and were discharged a few days later without complications. Dual infection with primary respiratory pathogens was also noted in several studies,3,4,6 and the role of SAFV as a primary agent of pathology in these cases is discussed. Although the proportion of positive specimens with SAFV is not too high, we can note that as with other respiratory viruses, SAFV might show seasonal pattern variations, with
Respiratory viruses detected in respiratory specimens from pediatric and immunosuppressed adults over a three-year
Pediatric (N Z 608) Adults (N Z 595)
Influenza A (%)
Influenza B (%)
RSV (%)
ADV (%)
Parainfluenza type-3 (%)
Picornavirus (%)a
hBoV (%)
hMPV (%)
SAFV (%)
21 (3.5)
17 (2.8)
84 (13.8)
18 (3.0)
16 (2.6)
12 (2.0)
26 (4.3)
17 (2.8)
8 (1.3)
9 (1.5)
9 (1.5)
8 (1.3)
1 (0.2)
10 (1.6)
1 (0.2)
9 (1.5)
5 (0.8)
0 (0)
Dual infection episodes detected in pediatric patients: five RSV þ hBoV, two ADV þ hMPV, one ADV þ parainfluenza-3, one hBoV þ hMPV, one picornavirus þ hBoV, and one RSV þ parainfluenza-3. SAFV co-infection with adenovirus was detected in two pediatric patients. Co-infection cases detected in adult patients: two influenza A þ picornavirus, one influenza B þ picornavirus and one RSV þ parainfuenza type-3 virus. a Eight isolates of Picornaviridae family were identified as members of Enterovirus genus.
680
Letters to the Editor
displacement between genotypes every year. The phylogenetic analysis showed three different genetic lineages of SAFV: five corresponded to genotype 2, two corresponded to genotype 3 and one corresponded to genotype 6. The seasonal distribution was noted, with a peak in May 2004, and a detection rate of 50% (4 out of 8 specimens): one belonged to SAFV-6 and the other three belonged to SAFV2. Between January 2005 and April 2005, two cases were detected, both SAFV type-3; and between November 2005 and April 2006, the last two infections were identified as genotype 2. We also observed that the genotype of SAFV does not seem to imply greater severity or a disposition to produce more co-infection with other viruses. Further studies are necessary to better understand the dynamic of SAFV infection in the respiratory tract. Our results suggest that SAFV is a rare cause of respiratory disease in children attended to the hospital, and coinfection with other pathogens is frequent. To our knowledge, this is the first study that includes immunosuppressed patients, and we did not find SAFV in this population. In light of our data, and the rest of the published literature, we do not consider SAFV to be a virus to look for in routine clinical practice in respiratory specimens. Consideration for SAFV in certain situations in which other primary agents have been ruled out might be appropriated.
Lineages of a Novel Saffold cardiovirus in humans. Emerg Infect Dis 2008;14(9):1398e405. €ttiger B, Banner J, Hoffmann T, Nielsen LP. 10. Nielsen AC, Bo Serious invasive saffold virus infections in children, 2009. Emerg Infect Dis 2012;18(1):7e12.
Acknowledgments
Absence of occult Hepatitis E virus infection among HIV immunosuppressed patients
This study was supported by a grant (MMA 2007-056) from n Mutua Madrilen ~a. the Fundacio
References 1. Kobayashi M, Tsukagoshi H, Ishioka T, Mizuta K, Noda M, Morita Y, et al. Seroepidemiology of Saffold cardiovirus (SAFV) genotype 3 in Japan. J Infect 2013;66(2):191e3. 2. Abed Y, Boivin G. New Saffold cardioviruses in 3 children, Canada. Emerg Infect Dis 2008;14(5):834e6. 3. Ren L, Gonzalez R, Xie Z, Xiao Y, Li Y, Liu C, et al. Saffold cardiovirus of 3 Lineages in children with respiratory tract infections, Beijing, China. Emerg Infect Dis 2010;16(7):1158e61. 4. Itagaki T, Abiko C, Aoki Y, Ikeda T, Mizuta K, Noda M, et al. Saffold cardiovirus infection in children associated with respiratory disease and its similarity to coxackievirus infection. Pediatr Infect Dis J 2011;30(8):680e3. 5. Tsukagoshi H, Masuda Y, Mizutani T, Mizuta K, Saitoh M, Morita Y, et al. Sequencing and phylogenetic analyses of saffold cardiovirus (SAFV) Genotype 3 isolates from children with upper respiratory infection in Gunma, Japan. Jpn J Infect Dis 2010;63:378e80. 6. Wang CYT, Greer RM, Delwart E, Sloots TP, Mackay IM. A newly designed real-time RT-PCR for SAFV detects SAFV-2 and SAFV-3 in the respiratory tracts of children during 2011. J Clin Virol 2012;55:173e6. 7. Peret T, Boivin G, Li Y, Couillard M, Humphrey C, Osterhaus A, et al. Characterization of human metapneumoviruses isolated from patients in North America. J Infect Dis 2002;185:1660e3. 8. Maggi F, Andreoli E, Pifferi M, Meschi S, Rocchi J, Bendinelli M. Human bocavirus in Italian patients with respiratory diseases. J Clin Virol 2007;38:321e5. €cker A, Almeida PS, 9. Drexler JF, Kleber de Bouza Luna L, Sto Medrano Ribeiro TC, Peterson N, et al. Circulation of 3
~as* Patricia Bran Monica Garcıa Columbiana Prieto Lola Folgueira Department of Clinical Microbiology, University Hospital 12 de Octubre, Avda. Cordoba s/n, 28041 Madrid, Spain *Corresponding author. Department of Clinical Microbiology, University Hospital 12 de Octubre, Avda. Cordoba s/n, 28041 Madrid, Spain. Tel./fax: þ34 917 792 416.
~as) E-mail address: [email protected] (P. Bran Accepted 14 November 2014
http://dx.doi.org/10.1016/j.jinf.2014.11.006 ª 2014 The British Infection Association. Published by Elsevier Ltd. All rights reserved.
We have recently published a high Hepatitis E virus (HEV) seroprevalence among HIV-infected patients.1 We found an HEV seroprevalence of 9.8% [95% CI: 8.02%e11.9%]. Among HEV seropositive patients in five RNA-HEV was amplified. HIV patients could lack or delay antibody production against several viral co-infections. Hepatitis C (HCV) and Hepatitis B (HBV) have been identified in immunosuppressed HIV-infected patients in whom hepatitis IgG/IgM was not detected.2,3 This situation has not been evaluated in the context of HEV infection, and no studies have been designed to examine this trend. One limitation of our study was that HEV-RNA was only tested in those patients with IgG/ IgM þ antibodies. Consequently, the HEV-RNA prevalence could be underestimated. Thus, we set up an study to evaluate the presence of RNA-HEV in HIV-infected patients with low CD4þ cell counts who did not have HEV antibodies. HIV type-I-infected patients with CD4þ total cell counts lower than 200 cells/mL attending the Infectious Diseases rdoba Unit of the Hospital Universitario Reina Sofıa de Co (Southern Spain) from September 2012 to September 2013 were included in this prospective transversal study. At the time of inclusion, patients underwent a clinical examination and routine hematological, biochemical, immunological and virological assessments. All patients were tested for HEV using ELISA for anti-HEV IgG (Wantai HEV-IgG ELISA; Beijing Wantai Biological Pharmacy Interpriseª LTD, Beijing, China) and anti-HEV IgM (Wantai HEV-IgM ELISA; Beijing Wantai Biological Pharmacy Interpriseª LTD, Beijing, China). Serum samples were stored at 80 C prior
