| 1. |
- Ahmed, Sheik, et al.
(författare)
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Thalassemia Patients from Baluchistan in Pakistan Are Infected with Multiple Hepatitis B or C Virus Strains
- 2021
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Ingår i: American Journal of Tropical Medicine and Hygiene. - : American Society of Tropical Medicine and Hygiene. - 0002-9637 .- 1476-1645. ; 104:4, s. 1569-1576
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Tidskriftsartikel (refereegranskat)abstract
- There are an estimated 2,000 children with 6-thalassemia in the province Baluchistan of Pakistan. These children are at high risk of acquiring transfusion-transmitted infections (TTIs) due to their need of regular blood transfusions for survival. Therefore, we investigated the frequencies of TTIs among these multi-transfused patients in a region where the WHO guidelines for blood safety are not always followed. Sera from 400 children (mean age 7.7 +/- 4.70 years) treated at two thalassemia centers in Baluchistan were investigated for TTIs. Eleven (2.8%) were hepatitis B surface antigen positive, and 72 (18.3%) had anti-hepatitis C virus (HCV), two of which were infected with both viruses. Only 22% of the children had been reached by the program for universal hepatitis B virus (HBV) vaccination which started in 2004. Half (51%) of the HCV infected had also been HBV infected. The HBV- and HCV-infected patients were older and had received more blood transfusions than the uninfected patients (P < 0.001). Molecular characterization of the viral strains revealed the presence of several genetically different strains in at least three HBV- and seven HCV-infected children. This is the first study to demonstrate infections with multiple HBV or HCV strains simultaneously infecting thalassemia patients. These may become the source for new emerging recombinant viruses of unknown virulence. The high prevalence of anti-HCV-positive children, and the presence of HBV infections among children who should have been vaccinated, highlights an urgent need for improvements of blood safety in this region of Pakistan.
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| 2. |
- Ayukekbong, James, et al.
(författare)
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Molecular Analysis of Enterovirus in Cameroon by Partial 50UTR-VP4 Gene Sequencing Reveals a High Genetic Diversity and Frequency of Infections
- 2014
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Ingår i: Journal of Medical Virology. - : Wiley. - 0146-6615. ; 86:12, s. 2092-2101
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Tidskriftsartikel (refereegranskat)abstract
- Enteroviruses (EVs) often infect humans, presenting as endemic or epidemic infections. In this study, the diversity of infecting EVs was studied among 146 children and 137 adults in a small community in Cameroon. The participants provided 2,458 fecal samples during 1-year monthly collection; 10 or more samples were obtained from 55%. Partial 5UTR-VP4 region could be sequenced in 393/547 PCR positive samples obtained from 119 children and 85 adults. EV-RNA was detected in at least one sample from 235 participants (83%) during the study period. A total of 121 different strains were identified, 66 infected only children, 29 only adults, and 26 infected both children and adults. There were children with up to five episodes with different strains, and adults with up to four such episodes. Infants aged <5 years were significantly more often EV infected compared to older participants. Infections with species EV-C constituted two third of all cases, and overall EV infections were more common during the rainy season. Species EV-B more often infected children than adults. Most strains were detected only for certain months of the year; however five strains were observed during the time spans of 5-10 months. Two strains were excreted up to eight months in three children and one adult. In 11 of the 128 families with paired samples the child and the adult were infected simultaneously by the same strain, indicating common source of infection. The study revealed a surprising complexity of EV ecosystem in a single community. J. Med. Virol. 86:2092-2101, 2014. (c) 2014 Wiley Periodicals, Inc.
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| 3. |
- Ayukekbong, James, et al.
(författare)
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Shift of Enterovirus species among children in Cameroon - Identification of a new enterovirus, EV-A119
- 2013
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Ingår i: Journal of Clinical Virology. - : Elsevier BV. - 1386-6532. ; 58:1, s. 227-232
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Tidskriftsartikel (refereegranskat)abstract
- Background: Infections caused by human enteroviruses (EVs) are often asymptomatic or mild, although they may cause more severe illnesses as meningitis and acute flaccid paralysis. EVs have globally posed a threat to children, and outbreaks of aseptic meningitis and hand, foot and mouth disease are frequently reported. Objective: To identify EV strains circulating among healthy children in a small community in Limbe, Cameroon two years apart. Study design: Species and EV types were obtained by partial 5'UTR-VP4 and VP1 sequencing of RNA from stool samples collected in October 2009 and September 2011 from 150 children in Cameroon. Results: In all, 74 children (49%) were infected with 28 different types of EV. There were 29 (54%) infected children in 2009, and 45 (47%) in 2011. There was a significant difference between detected species of EV, with 15 (47%) children infected with EV-A in 2009, and 22 (71%) with EV-B in 2011 (p = 0.0001). In 2009, one child was infected by a divergent EV, which was most similar to EV-A90. Based on the complete VP1 sequence, it was shown to be a new EV designated EV-A119. Conclusion: The current study shows a high heterogeneity of circulating EV types among children in Limbe, Cameroon, and a previously not described shift in predominating EV species. (C) 2013 Elsevier B. V. All rights reserved.
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| 4. |
- Beck-Friis, Thomas, et al.
(författare)
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Comparison of SARS-CoV-2 spike RNA sequences in feces and nasopharynx indicates intestinal replication
- 2022
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Ingår i: Gut Pathogens. - : Springer Science and Business Media LLC. - 1757-4749. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- Background Little is known of possible selection and replication of SARS-CoV-2 in the intestines and if viral load in feces is associated with severity of disease. Therefore, sequence variations of the spike region in strains collected from feces and nasopharynx (NPH) from the same patients were compared. It was also investigated whether viral load in feces related to severity of COVID-19 in hospitalized patients. Results SARS-CoV-2 RNA was found in 88 (79%) fecal samples from 112 patients. The complete spike region could be sequenced in 15 fecal and 14 NPH samples. Fourteen Alpha-variants and one Beta-variant of SARS-CoV-2 were identified. The majority of the viral genetic variants (viral populations) in two fecal samples, but none in NPH, had a reversion of the H69/V70 amino acid deletion normally seen in the Alpha variants. Nine fecal samples contained up to nine minority variants, each which may constitute a separate viral population. Five NPH samples had one genetic variant each, and one NPH sample contained nine minority populations of SARS-CoV-2 spike genes. Conclusions The higher genomic diversity of SARS-CoV-2 in feces compared to NPH, and the reversion of the H69/V70 deletion in Alpha variants from feces indicate a selection of viral strains and replication of SARS-CoV-2 in the gastrointestinal tract.
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| 5. |
- Ederth, Josefine, et al.
(författare)
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Molecular characterization of HCV in a Swedish county over 8 years (2002-2009) reveals distinct transmission patterns.
- 2016
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Ingår i: Infection ecology & epidemiology. - : Informa UK Limited. - 2000-8686. ; 6
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Tidskriftsartikel (refereegranskat)abstract
- Hepatitis C virus (HCV) is a major public health concern and data on its molecular epidemiology in Sweden is scarce. We carried out an 8-year population-based study of newly diagnosed HCV cases in one of Sweden's centrally situated counties, Södermanland (D-county). The aim was to characterize the HCV strains circulating, analyze their genetic relatedness to detect networks, and in combination with demographic data learn more about transmission.
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| 6. |
- Elduma, A. H., et al.
(författare)
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A Single Lineage of Hepatitis E Virus Causes both Outbreaks and Sporadic Hepatitis in Sudan
- 2016
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Ingår i: Viruses. - : MDPI AG. - 1999-4915. ; 8:10
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Tidskriftsartikel (refereegranskat)abstract
- Few studies have reported sporadic hepatitis E virus (HEV) infections during non-outbreak periods in Africa. In this study, the prevalence of HEV infection in Sudan was investigated in 432 patients with acute hepatitis from 12 localities in North Kordofan, and from 152 patients involved in smaller outbreaks of hepatitis in the neighbouring Darfur. HEV infection was diagnosed in 147 (25%) patients: 98 from Kordofan and 49 from Darfur. The mortality was 10%; six of the patients who died from the infection were pregnant women. HEV RNA was detected by quantitative real-time polymerase chain reaction (RT-qPCR) in 38 (26%) patients: 22 from Kordofan and 16 from Darfur. Partial open reading frame (ORF) 1 and ORF2 were sequenced from HEV from nine and three patients, respectively. Phylogenetic analysis showed that the Sudanese strains belonged to genotype 1 (HEV1), and confirmed the segregation of African HEV1 strains into one branch divergent from Asian HEV1. It also revealed that the Sudanese strains from this study and from an outbreak in 2004 formed a separate clade with a common ancestor, distinct from strains from the neighbouring Chad and Egypt. This HEV strain has thus spread in a large area of Sudan, where it has caused both sporadic hepatitis E and outbreaks from at least 2004 and onwards. These data demonstrate that hepatitis E is a constant, on-going public health problem in Sudan and that there is a need for hepatitis E surveillance, outbreak preparedness, and general improvements of the sanitation in these remote areas of the country.
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| 7. |
- Elfaitouri, Amal, 1974-
(författare)
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Development of Real-Time PCR Based Methods for Detection of Viruses and Virus Antibodies
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Quantitative real-time PCR (QPCR) technology has been very useful for diagnosis of viral diseases. QPCR has recently reached a level of sensitivity, simplicity, and reproducibility which allows a large number of samples to be screened rapidly, make it a suitable tool for the clinical virology diagnostics. In this thesis, broadly targeted and degenerated quantitative QPCR assays were used. A somewhat novel single-tube real-time reverse transcription-polymerase chain reaction (QRT-PCR), with takes advantage of ability of rTth DNA polymerase to reverse transcribe RNA in the presence of Mn2+ at elevated temperatures and includes protection against amplimer contamination by using thermolabile UNG, was developed. A new technique for diagnostic of recent viral infection by detection of viral immunoglobulin M (IgM) was also developed. In the first paper, a sensitive single-tube QRT-PCR for detection of enteroviral RNA in patients with aseptic meningitis was presented. In the second paper, a single-serum-dilution real-time PCR-based PIA (PCR-enhanced immunoassay), called quantitative PIA (QPIA), to detect enterovirus IgM for diagnosis of EV infection in patients with aseptic meningitis, was also developed. In the third paper, a broadly targeted, simple, single tube degenerated quantitative QPCR technique for detection of JCV, BKV and SV40 DNA was developed. A conserved region of the VP2 gene of JCV, BKV and SV40 was targeted. A false positive result due to contamination with commonly used SV40 T-antigen plasmids was therefore avoided. In manuscript four, the QPIA assay provide a rational strategy for detection of EV IgM, allows the use of viral antigens isolate from newly diagnosed Type 1 diabetes patients (T1D-EV-QPIA) to measured IgM against diabetogenic viruses in serum from newly diagnosed T1D children, siblings, and healthy children. To conclude, novel broadly targeted real-time PCR methods for diagnosis of entero- and polyoma viral infections were developed.
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| 8. |
- Fonseca, M. C., et al.
(författare)
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Molecular Characterization of Coxsackievirus A24v from Feces and Conjunctiva Reveals Epidemiological Links
- 2021
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Ingår i: Microorganisms. - : MDPI AG. - 2076-2607. ; 9:3
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Tidskriftsartikel (refereegranskat)abstract
- Coxsackievirus A24 variant (CVA24v), the main causative agent of acute hemorrhagic conjunctivitis (AHC), can be isolated from both the eyes and lower alimentary tract. However, the molecular features of CVA24v in feces is not well-documented. In this study, we compared the VP1 and 3C sequences of CVA24v strains isolated from feces during AHC epidemics in Cuba in 1997, 2003, and 2008-2009 with those obtained from conjunctival swabs during the same epidemic period. The sequence analyses of the 3C and VP1 region of stool isolates from the three epidemics showed a high degree of nucleotide identity (ranging from 97.3-100%) to the corresponding conjunctival isolates. The phylogenetic analysis showed that fecal CVA24v isolates from the 1997 and 2003 Cuban outbreaks formed a clade with CVA24v strains isolated from conjunctival swabs in Cuba and other countries during the same period. There were three amino acid changes (3C region) and one amino acid change (VP1 region) in seven CVA24v strains isolated sequentially over 20 days from fecal samples of one patient, suggesting viral replication in the intestine. Despite these substitutions, the virus from the conjunctival swab and fecal samples were genetically very similar. Therefore, fecal samples should be considered as a reliable alternative sample type for the routine molecular diagnosis and molecular epidemiology of CVA24v, also during outbreaks of AHC.
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| 9. |
- Fonseca, M. C., et al.
(författare)
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Molecular evolution of coxsackievirus A24v in Cuba over 23-years, 1986-2009
- 2020
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- Coxsackievirus A24 variant (CVA24v) is a major causative agent of acute hemorrhagic conjunctivitis outbreaks worldwide, yet the evolutionary and transmission dynamics of the virus remain unclear. To address this, we analyzed and compared the 3C and partial VP1 gene regions of CVA24v isolates obtained from five outbreaks in Cuba between 1986 and 2009 and strains isolated worldwide. Here we show that Cuban strains were homologous to those isolated in Africa, the Americas and Asia during the same time period. Two genotypes of CVA24v (GIII and GIV) were repeatedly introduced into Cuba and they arose about two years before the epidemic was detected. The two genotypes co-evolved with a population size that is stable over time. However, nucleotide substitution rates peaked during pandemics with 4.39x10(-3) and 5.80x10(-3) substitutions per site per year for the 3C and VP1 region, respectively. The phylogeographic analysis identified 25 and 19 viral transmission routes based on 3C and VP1 regions, respectively. Pandemic viruses usually originated in Asia, and both China and Brazil were the major hub for the global dispersal of the virus. Together, these data provide novel insight into the epidemiological dynamics of this virus and possibly other pandemic viruses.
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| 10. |
- Frankal, Miriam, 1983, et al.
(författare)
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Hepatitis E Virus Infection, a Risk for Liver Transplant Recipients in Sweden
- 2022
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Ingår i: Transplantation Direct. - 2373-8731. ; 8:12
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Tidskriftsartikel (refereegranskat)abstract
- Background. Following exposure to hepatitis E virus (HEV), liver transplant (LT) recipients have an increased risk of developing chronic infection, which may rapidly progress to severe liver damage if not treated. The prevalence of HEV infection after LT is unclear and likely varies geographically. The aim of this study was to investigate the prevalence of acute and chronic HEV infection among LT recipients in an HEV endemic region. Methods. During 2013 to 2015, 109 of 152 prospectively enrolled patients listed for LT received a liver graft and completed the study protocol. They were evaluated for anti-HEV IgM, HEV IgG, and HEV RNA at the time of LT assessment and 3 and 12 mo post-LT. Medical records were reviewed. Results. Twelve (11%) LT recipients acquired markers of HEV infection during the study period. Seven patients (6%) had detectable HEV RNA, 1 before LT and 3 at the 3-mo and another 3 at the 12-mo follow-up post-LT. All resolved their infections without treatment and had undetectable HEV RNA at the succeeding follow-up. Another 5 (5%) patients developed anti-HEV antibodies without detectable HEV RNA as an indication of HEV infection during follow-up. Signs and symptoms of HEV infection were subtle‚ and none were diagnosed in routine clinical care. Conclusion. A substantial proportion of LT recipients in Sweden are at risk of acquiring HEV infection, both before and after LT. The results highlight the frequency of silent, spontaneously resolving HEV infections and do not support universal screening of LT recipients in Sweden, despite HEV being a potentially treatable infection.
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