Disproportionate Distribution of HBV Genotypes A and D and the Recombinant Genotype D/E in the High and Low HBV Endemic Regions of Uganda: A Wake-Up Call for Regional Specific HBV Management

Viruses associated with measles-like illnesses in Uganda

OBJECTIVES

In this study, we investigated the causes of measles-like illnesses (MLI) in the Uganda national surveillance program in order to inform diagnostic assay selection and vaccination strategies.

METHODS

We used metagenomic next-generation sequencing (M-NGS) on the Illumina platform to identify viruses associated with MLI (defined as fever and rash in the presence of either cough, coryza or conjunctivitis) in patient samples that had tested IgM negative for measles between 2010 and 2019.

RESULTS

Viral genomes were identified in 87/271 (32%) of samples, of which 44/271 (16%) contained 12 known viral pathogens. Expected viruses included rubella, human parvovirus B19, Epstein Barr virus, human herpesvirus 6B, human cytomegalovirus, varicella zoster virus and measles virus (detected within the seronegative window-period of infection) and the blood-borne hepatitis B virus. We also detected Saffold virus, human parvovirus type 4, the human adenovirus C2 and vaccine-associated poliovirus type 1.

CONCLUSIONS

The study highlights the presence of undiagnosed viruses causing MLI in Uganda, including vaccine-preventable illnesses. NGS can be used to monitor common viral infections at a population level, especially in regions where such infections are prevalent, including low and middle income countries to guide vaccination policy and optimize diagnostic assays.

A review of epidemiology and clinical relevance of Hepatitis B virus genotypes and subgenotypes

BACKGROUND

Hepatitis B virus (HBV) infection is a global public health burden, affecting nearly 300 million people around the world. Due to HBV population is considered to be represented as a viral quasispecies with genetic diversity, some reports showed that different genotypes of HBV have different viral effects, though the emergence of antiviral drugs that effectively inhibit viral replication, however, HBV infection has still not been eradicated and further research is needed.

SUMMARY

HBV has been classified into at least ten genotypes (A-J)  and more than 40 subgenotypes based on an intergroup or intragroup nucleotide difference across the whole genome, respectively. Inter genotypic recombinants were also observed during the HBV evolution. HBV genotypes and subgenotypes have distinct ethno-geographical distributions, as well as evident differences in their biological characteristics. HBV genotypes and subgenotypes also have close association with disease severity, long-term clinical outcomes, and response to antiviral therapy.

KEYMESSAGES

In this review, we up-dated the epidemiological characteristics, clinical features and prognosis of HBV infection with dissimilar genotype/subgenotypes, to better understanding and developing individualized prevention and treatment strategies.

Hepatitis B virus (HBV) serological patterns among the HBsAg negative hospital attendees screened for immunization

The Hepatitis B virus (HBV) is a highly infectious virus and is endemic in Uganda. It is one of the major etiological agents for liver diseases including liver cancer. In this work, we evaluated the prevalence of the HBV serological markers and the associated socio-demographic factors among hepatitis B surface antigen (HBsAg) seronegative persons screened during routine immunization against the virus in eastern Uganda. Data on the socio-demographic characteristics were collected using a structured questionnaire, while that on the serological markers were obtained from serum samples and evaluated by using the 5-panel HBV One Step Hepatitis B Virus Combo Test Device (Fastep^R, HBV-P43M). The following markers were evaluated by the panel: HBsAg, HBsAb, HBcAb, and HBeAb. Data were analyzed using SPSS (version 26), and multinomial logistic regression was used to elicit the adjusted odds ratio. All the analysis were performed at a 95% confidence limit, and a P value ≤ 0.05 was considered significant. The 424 participants included in this study were mainly female (62.3%), married (55.4%) and aged 30 years and above (54.2%). The seropositivity of the HBsAb, HBeAb, HBcAb marker prevalence rates was 48(11.3%), 73(17.2%) and 45(10.6%) respectively. The majority of the participants (327, 77.1%) did not present with any marker. Married paricipants were significantly associated with reduced HBsAb seropositvity rate, whereas young people aged 18–29 years were associated the with increased odds of HBsAb seropositivity (p < 0.05). Male participants were significantly associated with the HBeAb and HBcAb seropositivity (p < 0.05). Similarly, contact with an HBV infected person was significantly associated with HBeAb and HBcAb seropositivity (p < 0.05). Further still, blood transfusion was significantly associated with the increased risk of HBcAb seropositivity (P < 0.05). This study has revealed a prevalence of HBV serological markers among the HBsAg seronegative persons in this community and an increased risk of transmission of the virus in the community. Our findings have key consequences pertaining the interventions that are pertinent in the control and prevention of the spread of the virus among apparently health persons.

A Novel NCSTN Mutation in a Three-Generation Chinese Family with Hidradenitis Suppurative

Objective

Hidradenitis suppurativa (HS) is a rare autosomal dominant condition characterized by inflamed nodules, cysts, deep abscesses, draining sinuses in the axillae, inguinal, and anogenital regions. Mutations in the NCSTN gene have been perceived to be responsible for the major underlying changes in the disorder. The purpose of this study is to identify a novel gene mutation in a Chinese family with HS.

Methods

A Chinese family with HS present was investigated. The proband had manifested with multiple draining sinuses on the posterior neck, chest, bilateral axillae, and perineal regions. DNA was isolated from the peripheral blood of the family members. The encoding exons with introns of the NCSTN gene were analyzed by polymerase chain reactions (PCR) and direct DNA sequencing. Sanger sequencing was performed to confirm the next-generation sequencing results and to analyze each mutation's familial segregation. Furthermore, the identified mutation was localized onto a 3D structure model using the DeepView Swiss-PdbViewer 4.1 software.

Results

In this family comprising 10 HS patients, one novel mutation of the NCSTN gene was identified, involving a deletion mutation (c.447delC(p.N150Ifs∗52)) in the NCSTN gene resulting in a frameshift and the new formation of a hydrogen bond.

Conclusion

Our study reports the identification of a novel mutation that causes familial HS and could expand the spectrum of mutations in the γ-secretase genes underlying HS.