In brief

In their review, researchers emphasise that understanding the pathology of mpox infections, the long-term impact of the disease, and the impact of clinical tools such as vaccines and contact tracing are critical to slowing the spread of the virus in vulnerable communities.

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What’s behind the rise of mpox?

12 Jul 2023

Scientists survey how the mpox virus spreads through populations, the immunology of infections and current treatment interventions.

Last year, mpox infections flipped from being mostly restricted to hotspots in Africa to becoming a global health emergency. According to the World Health Organization (WHO) the unprecedented outbreak of mpox, previously known as monkeypox, recorded a cumulative total of 87,113 laboratory-confirmed cases, including 130 deaths from 1 January 2022 through 24 April 2023.

Fok-Moon Lum, an Investigator at the A*STAR Infectious Diseases Labs (ID Labs) said that the event sparked a flurry of research activity around the how and why of the virus’ unexpected rise. “Some of the major reasons for this spread could be attributed to waning smallpox immunity in the general population and the termination of the smallpox vaccination regime,” explained Lum.

In collaboration with teams at the National Centre for Infectious Diseases, Singapore, Lum and colleagues embarked on an in-depth review of studies in the field to help steer efforts to control the spread of mpox.

The researchers documented how the mpox virus affects host cells by interfering with cell signalling pathways and turning off the body’s protective immune mechanisms. They also identified an urgent need for defining immune biomarkers specific to mpox infections to help evaluate the efficacy of new vaccines. According to Lum, safe and effective vaccines are critical for shielding vulnerable populations such as pregnant women and children against the virus.

In addition, the team identified another gap in our understanding of the B.1 lineage, an emerging lineage of the Western African mpox strain that spread prolifically during the 2022 global outbreak. The researchers offered valuable insights on the evolution of this strain by comparing it to the genetics of SARS-CoV-2.

Unlike the genome of the COVID-causing virus which is RNA-based, mpox’s genetic material is encoded in DNA. Since DNA is more resistant to errors during replication in the host than RNA, mpox is less likely to produce mutant variants of increasing transmissibility.

Nonetheless, the team pointed to a series of genetic changes called single nucleotide polymorphisms present in the genome of the B.1 lineage, which can affect the function of the protein that the gene encodes, and explain its enhanced transmissibility and sudden worldwide spread. “As with other viruses, it is expected that the mpox virus will continue to mutate to obtain beneficial features for its own evolution and spread,” warned Lum.

Lum said that the group’s current interests lie in mapping host responses to active mpox infections. The team has collected samples from local patients and will leverage on the ID Labs’ repertoire of advanced immunological tools to help answer lingering questions in the field.

“This is extremely important as the mpox virus has accrued an arsenal of genes encoding for proteins that are capable of subverting the host immune responses,” said Lum.

The A*STAR-affiliated researchers contributing to this research are from the A*STAR Infectious Diseases Labs (ID Labs).

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Lum, F.-M., Torres-Ruesta, A., Tay, M.Z., Lin, R.T.P., Lye, D.C., et al. Monkeypox: disease epidemiology, host immunity and clinical interventions. Nature Reviews Immunology 22, 597-613 (2022). | article

About the Researchers

Fok-Moon Lum graduated from the National University of Singapore with a Degree in Biomedical Sciences. Following this, he embarked on a PhD journey under the tutelage of Lisa Ng, then at A*STAR’s Singapore Immunology Network, where he was involved in elucidating the host immune response to the chikungunya virus. After his PhD studies, he stayed on as a postdoctoral fellow and worked on the Zika virus, during the outbreak in 2016-2017 before spending two years of overseas post-doctoral training at Stanford University under the A*STAR International Fellowship. He is now an Investigator at the A*STAR Infectious Diseases Labs, where he is attempting to investigate the involvement of neurotransmitters in infectious diseases.
Lisa F.P. Ng obtained her PhD in molecular virology in coronaviruses from the National University of Singapore (NUS) in 2002. After joining A*STAR’s Genome Institute of Singapore (GIS) in 2002 as a Postdoctoral Fellow, she worked on viral diseases such as hepatitis, severe acute respiratory syndrome and influenza. Ng is currently the Executive Director at A*STAR Infectious Diseases Labs (ID Labs) where she focuses on the immune responses to arthritic arboviruses that are epidemic or highly endemic in the tropical region. Ng has won numerous accolades for her research, including the ASEAN ‘International Young Scientist and Technologist Award’ in 2008 and A*STAR’s ‘Most Inspiring Mentor Award’ in March 2013.

This article was made for A*STAR Research by Wildtype Media Group