{
  "abstract": "Background In Cameroon HBV infection is endemic. However, limited data are available on epidemiology, genetic diversity and accurate diagnosis of HDV infection.Material and Methods We conducted a cross-sectional study on 117 HBsAg+ patients from two hospitals in Cameroon, and 42 patients with an already known anti-HDV positivity. For the 117 HBsAg+ patients, anti-HDV were detected by using an assay on the Diasorin Liaison XL analyser. For samples resulted positive to anti-HDV, HDV-RNA was tested by two different assays: RoboGene HDV-RNA quantification kit v3.0 using the Felix automated extraction instrument (LOD <6 IU/ml) and the fully automated Altostar platform for extraction and HDV RT-PCR v1.5 (LOD 1.12 IU/ml). Whole genome HDV sequencing was assessed on Illumina MiSeq. The correlation between HDV-RNA values by Robogene and Altostar assays was assessed by Spearmann test.Results Overall, 21/117 (18%) patients were positive to anti-HDV, highlighting a high rate of HDV seroprevalence. The percentage of anti-HDV positive patients ranged from 15.1% (11/73) in the Littoral region up to 22.7% (10/44) in the East region, highlighting local hotspot with high HDV endemicity.HDV-RNA was tested in the 21 newly diagnosed patients and in the 42 with previously known anti-HDV positivity for a total of 63 patients. Among them, 61% had detectable HDV-RNA by Robogene assay (median [IQR]: 5.4 [3.3 - 6.0] log[IU/ml]), supporting a conspicuous circulation of active HDV infection with an intense HDV replication. Overall, HDV-RNA quantification by Robogene and Altostar showed a high degree of correlation (Rho=0.91). Such degree of correlation was reduced for HDV-RNA values >5 log(IU/ml) (Rho=0.82 for HDV-RNA >5 log[IU/ml] vs Rho=0.99 for HDV-RNA <5 log[IU/ml]).Focusing on 38 samples with HDV-RNA >1000 IU/ml by Robogene, 26 were successfully sequenced. Phylogenetic analysis revealed the circulation of a large variety of HDV genotypes and subgenotypes with the subgenotype 1b being the most frequent (61.5%), followed by 1a (19.3%), genotype 7 (7.8%), genotype 6, 5 and 1e present in 3.8% of patients each. The correlation between HDV-RNA quantification by Robogene and Altostar was very high in all identified genotypes/subgenotypes with a slight decrease in 1b (Rho=0.96 for genotypes/sub-genotypes other than 1b and 0.82 for 1b.Conclusions These findings show a significant burden of active HDV infection in Cameroon, thus highlighting the urgent need of developing accessible and affordable diagnostic algorithms and surveillance tools for HDV infection in Cameroon to reduce HDV-associated morbidity.",
  "authors": [
    {
      "affiliations": [
        "Department of Biology, University of Rome Tor Vergata, Rome, Italy"
      ],
      "name": "L Piermatteo"
    },
    {
      "affiliations": [
        "Department of Microbiology, Virology, Parasitology, Hematology and Infectious Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Yaoundé, Cameroon"
      ],
      "name": "EL Lebomo Etogo"
    },
    {
      "affiliations": [
        "Department of Biomedical Sciences, Faculty of Sciences, University of Ngaoundere, Cameroon"
      ],
      "name": "C Lobe"
    },
    {
      "affiliations": [
        "Department of Biology, University of Rome Tor Vergata, Rome, Italy"
      ],
      "name": "A Magnapera"
    },
    {
      "affiliations": [
        "Department of Experimental Medicine, University of Rome Tor Vergata, Rome, Italy"
      ],
      "name": "L Carioti"
    },
    {
      "affiliations": [
        "Laboratory of Virology and Laboratories of Biosafety, National Institute for Infectious Diseases Lazzaro Spallanzani-IRCCS, Rome, Italy"
      ],
      "name": "L Fabeni"
    },
    {
      "affiliations": [
        "Department of Biology, University of Rome Tor Vergata, Rome, Italy"
      ],
      "name": "G Torre"
    },
    {
      "affiliations": [
        "Department of Biology, University of Rome Tor Vergata, Rome, Italy"
      ],
      "name": "I Grossi"
    },
    {
      "affiliations": [
        "Department of Biology, University of Rome Tor Vergata, Rome, Italy"
      ],
      "name": "S D’Anna"
    },
    {
      "affiliations": [
        "Department of Microbiology, Faculty of Medicine and Pharmaceutical Sciences, University of Douala, Cameroon"
      ],
      "name": "G Pascal Ngaba"
    },
    {
      "affiliations": [
        "Department of Microbiology, Virology, Parasitology, Hematology and Infectious Diseases, Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Yaoundé, Cameroon"
      ],
      "name": "E Enjema Lyonga"
    },
    {
      "affiliations": [
        "Department of Experimental Medicine, University of Rome Tor Vergata, Rome, Italy"
      ],
      "name": "F Ceccherini-Silberstein"
    },
    {
      "affiliations": [
        "Department of Biology, University of Rome Tor Vergata, Rome, Italy"
      ],
      "name": "R Salpini"
    },
    {
      "affiliations": [
        "Department of Biochemistry, Faculty of Medicine and Biomedical Sciences, University of Yaoundé I, Yaoundé, Cameroon"
      ],
      "name": "JN Torimiro"
    },
    {
      "affiliations": [
        "Department of Biology, University of Rome Tor Vergata, Rome, Italy"
      ],
      "name": "V Svicher"
    }
  ],
  "title": "P231 Broad genetic diversity of HDV and high prevalence of active HDV infection in Cameroon: insights from molecular diagnostics and whole-genome sequencing",
  "uid": "a13c06fc-46a1-5b69-8249-59bdfc839123"
}