Joakim Øverbø

Mr. Joakim Øverbø

orcid

Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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2 January 2023 in Vaccine
Verified
Journal Article
Open access
JØJoakim Øverbø
Joakim Øverbø
AAAsma Aziz
Asma Aziz
KZK Zaman
K Zaman
JCJohn Clemens
John Clemens
CJCathinka Halle Julin
Cathinka Halle Julin
SDSusanne Gjeruldsen Dudman
Susanne Gjeruldsen Dudman
Hepatitis E virus (HEV) is a major cause of acute viral hepatitis worldwide and it contributes to considerable maternal and neonatal mortality and morbidity in many low-income countries like Bangladesh. A three-dose regimen of a vaccine against HEV (HEV 239) has shown promising results in China. The effects and safety of this vaccine in other populations and with different dosing regimens remains uncertain. Investigate the immune response and safety of a two-dose regimen with the HEV 239 vaccine among healthy adults. Examine the feasibility of conducting a larger HEV 239 vaccine trial in rural Bangladesh. One-hundred healthy men and non-pregnant women 16-39 years old were randomized in a 1:1 ratio to receive two doses of either the study (HEV) or control (Hepatitis B virus, HBV) vaccine (at 0, 1 month). Blood samples were collected at day 0, day 60 and 2 years after vaccination. The primary endpoints were the proportion and severity of adverse events up to 2 months after dose one and the longitudinal shift in anti-HEV IgG levels from day 0 to day 60 and 2 years after vaccination. Adverse events to HEV 239 were comparable to the control vaccine, mild in severity and resolved within one to nine days. All participants in the study group seroconverted and achieved high levels of HEV IgG antibodies that remained positive for two years in all but one. A T-cell response was detected one month after HEV 239 vaccination. Our results show that two doses of the HEV 239 vaccine produces broad and likely functional immune responses against HEV that remain for at least two years. The safety profile was acceptable and a phase four study of HEV 239 in rural Bangladesh is feasible. gov Identifier: NCT02759991.

15 November 2022 in Viruses
Verified
Journal Article
Open access
PDF file
JØJoakim Øverbø
Joakim Øverbø
AAAsma Aziz
Asma Aziz
KZK. Zaman
K. Zaman
CJCathinka Halle Julin
Cathinka Halle Julin
FQFirdausi Qadri
Firdausi Qadri
SDSusanne Gjeruldsen Dudman
Susanne Gjeruldsen Dudman
Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis worldwide. In many low-income countries it causes large outbreaks and disproportionally affects pregnant women and their offspring. Surveillance studies to find effective preventive interventions are needed but are hampered by the lack of funding and infrastructure. Dried blood spots (DBS) offer an easier and more robust way to collect, transport, and store blood samples compared to plasma/serum samples, and could ease some of the barriers for such studies. In this study we optimize an HEV IgG ELISA for DBS samples and validate it on 300 paired DBS and plasma samples collected in rural areas of Bangladesh from participants in a HEV vaccine study. We demonstrate that HEV IgG in blood stored as DBS is stable for two months at up to 40 °C, and for five freeze-thaw cycles. The specificity was 97% and the overall sensitivity of the DBS assay was 81%. The sensitivity was higher in samples from vaccinated participants (100%) compared to previously infected participants (59%), reflecting a positive correlation between IgG titer and sensitivity. We found a strong correlation between DBS and plasma samples with an r2 of 0.90, but with a higher degree of difference between individual paired samples. Our study shows that DBS offers a stable alternative to plasma/serum for HEV IgG measurements and can facilitate serological studies, particularly in resource limited areas.

1 December 2015 in BMC Infectious Diseases
Verified
Journal Article
Open access
PDF file
JMJoão Mesquita
João Mesquita
MMMette Myrmel
Mette Myrmel
KSKathrine Stene-Johansen
Kathrine Stene-Johansen
JØJoakim Øverbø
Joakim Øverbø
MNMaria S. J. Nascimento
Maria S. J. Nascimento
The discovery of autochthonous hepatitis E in industrialized countries has changed the understanding of hepatitis E virus (HEV) infection in these regions, now known to be mainly due to zoonotic transmission of genotype 3. The foodborne route of transmission via consumption of contaminated meat from HEV infected pigs is well documented as well as the direct occupational exposure to animal reservoirs. Accumulating evidence also points to an emerging potential threat to blood safety after the identification of viremic blood donors and the documentation of HEV-contaminated blood or blood products. Moreover, the origin of several iatrogenic cases remains unclear and porcine-derived pharmaceutic products have been suspected as a cause. Severe morbidity following HEV infection in patients receiving immunosuppressive therapy and in those with severe immunodeficiency from other causes has been recently recognized as a serious consequence of this infection in industrialized countries. In Portugal no large-scale HEV seroprevalence study has been undertaken, no professional risk groups have been identified, and the risk of blood donation from HEV silent infected donors is unknown. The present paper describes seroepidemiological and molecular approaches to answer these questions. To address these issues a study protocol was designed that will approach: i) the seroprevalence of HEV among the Portuguese general population; ii) HEV infection among butchers and slaughterhouse workers (occupational risk); iii) the silent HEV infection in Portuguese blood donors (HEV transfusion-associated risk); iv) the potential HEV contamination of porcine-derived pharmaceutical products. Commercial enzyme immunoassays and real-time/conventional RT-PCR assays will be used. This study is the first evaluation of the seroepidemiological status to HEV infection of the Portuguese population, the first to potentially identify professional risk groups, and to evaluate the safety of blood and blood products and porcine-derived pharmaceutics in Portugal. It will generate valuable data applicable for preventive and control measures against HEV infection (e.g., introduction of systematic screening of blood donors, control of blood products or porcine derived pharmaceutical products), thus helping to manage the burden of this viral disease.

24 December 2022 in Viruses
Verified
Journal Article
Open access
PDF file
AAAsma Aziz
Asma Aziz
JØJoakim Øverbø
Joakim Øverbø
SDSusanne Gjeruldsen Dudman
Susanne Gjeruldsen Dudman
CJCathinka Halle Julin
Cathinka Halle Julin
YKYoon Jeong Gabby Kwon
Yoon Jeong Gabby Kwon
JDJennifer Dembinski
Jennifer Dembinski
HEV is the most common cause of acute hepatitis globally. This review summarizes the latest knowledge on the epidemiology, clinical characteristics, testing, and treatment of HEV infection. We also focused on Bangladesh to highlight the distinct challenges and the possible remedies. In low-income settings, the virus is mainly transmitted between people by fecal contamination of drinking water causing large outbreaks, and sporadic cases. The disease is usually mild and self-limiting acute hepatitis. Still, pregnant women and their offspring in low-income countries are at particular risk for severe disease, with up to 20% maternal mortality. Despite the high burden of the disease, HEV remains a relatively neglected virus, with detection hampered by costly tests and a lack of suitable treatments. Molecular PCR diagnostics, together with ELISA antibody tests, remain the preferred methods for diagnosis of HEV; however, rapid bedside diagnostics are available and could offer a practical alternative, especially in low-income countries. One vaccine (HEV 239) is only available in China and Pakistan, as efficacy against the other genotypes remains uncertain. The effectiveness trial conducted in Bangladesh might lead the way in gathering more efficacy data and could, together with improved surveillance and raised awareness, dramatically reduce the global burden of HEV.

26 June 2025 in Viruses
Verified
Journal Article
Open access
PDF file
JØJoakim Øverbø
Joakim Øverbø
JDJennifer Dembinski
Jennifer Dembinski
TNToril Nilsen
Toril Nilsen
VSVethanayaki Sriranganathan
Vethanayaki Sriranganathan
VDVeselka Petrova Dimova-Svetoslavova
Veselka Petrova Dimova-Svetoslavova
SDSusanne Gjeruldsen Dudman
Susanne Gjeruldsen Dudman
Hepatitis E virus (HEV) causes significant morbidity and mortality globally, particularly affecting vulnerable populations such as pregnant women. HEV239 (Hecolin®), a recombinant vaccine containing the immunodominant protruding (E2) domain of the HEV capsid protein, has demonstrated effectiveness, yet detailed human cellular immune responses remain understudied. This study characterized humoral and cellular immune responses following vaccination with HEV239 or natural HEV infection in healthy Bangladeshi women aged 16–39 years. Using dual IFNγ and IL-4 ELISpot assays, we found robust, predominantly Th1-mediated cellular responses at 30 days after the third vaccine dose, comparable to responses during acute infection. Longitudinal antibody assessments confirmed sustained antibody production, primarily against the E2 domain of genotypes 1 and 3, persisting up to two years post-vaccination. Despite limitations related to sample size and assay sensitivity, our findings underscore the immunogenic potential of HEV239 and support a broader use in HEV-endemic regions.

19 August 2026 in Rheumatology
Verified
Journal Article
Open access
GHGunhild Hagen
Gunhild Hagen
AOAnna K Opheim
Anna K Opheim
JØJoakim Øverbø
Joakim Øverbø
EAEline Aas
Eline Aas
SPSella Aarrestad Provan
Sella Aarrestad Provan
Objectives: To assess the cost-effectiveness of vaccinating patients with rheumatoid arthritis (RA) with the adjuvanted recombinant zoster vaccine (RZV), compared with no vaccination. Methods: To predict health gains and costs from vaccination, we developed a decision-analytic Markov model with five health states: no herpes zoster, herpes zoster (HZ), postherpetic neuralgia (PHN), recovered from HZ and death. The model follows a hypothetical cohort of 10 000 patients with RA over a lifetime perspective and records events of HZ and PHN, along with quality-adjusted life years (QALYs) and costs from a healthcare perspective. Costs and health effects were discounted with 4% annually. Model inputs were collected from published literature and publicly available sources. Cost-effectiveness was evaluated using the incremental cost-effectiveness ratio (ICER), expressed as EUR per QALY, compared with a cost-effectiveness threshold of EUR 23 650 per QALY. We performed one-way and probabilistic sensitivity analyses. Results: Vaccination led to a reduction of 2550 cases of HZ and 1303 cases of PHN per 10 000 patients with RA vaccinated, resulting in an ICER of EUR 11 205/QALY. One-way sensitivity analyses revealed that the results were particularly sensitive to changes in the probability of developing PHN as a sequela of HZ. The probabilistic analysis indicated that the RZV had a 98% probability of being cost-effective at the assumed threshold value. Conclusion: Vaccinating patients with RA using RZV results in better health at higher cost compared with no vaccination. Under the assumptions made, vaccination is likely to be considered cost-effective for patients with RA.