Can we treat, or cure, chronic viral diseases?
Chronic viral disease
While acute (short-term) viral infections often get more attention, the realm of human viral disease extends far beyond these short-term illnesses. Many viruses have the capacity to establish persistent infections within their human hosts, leading to an array of chronic diseases with many serious long-term health implications. [1]
Chronic viral diseases cover a wide variety of conditions, ranging from Hepatitis and HIV/AIDS to less familiar afflictions such as human papillomavirus (HPV)-associated cancers, and chronic fatigue syndrome (CFS). While some chronic viral infections progress slowly over years or decades, others may remain asymptomatic for extended periods before flaring up and causing severe complications. While many chronic viral infections remain incurable, ongoing research into targeted antiviral therapies, immunotherapies, and gene editing technologies offers promising avenues for future treatments and potential cures.
The table below illustrates a small selection of some of these persistent viruses, the diseases/symptoms they cause, and an estimate of global case numbers.
Viral persistence and latent infection
Central to the way in which a chronic viral disease develops is the ability of viruses to establish persistent infections within host cells in the human body. Through mechanisms such as viral latency, immune evasion and integration into the host genome, viruses can evade detection by the immune system and maintain a lifelong residency within their hosts.
Some common examples of latent viruses include herpesviruses, which establish infections in the sensory ganglia (nerve and brain cells) and can reactivate to cause recurrent outbreaks, and retroviruses like HIV, which integrate into their host’s DNA and persist in spite of antiretroviral therapy.
Immune system dysregulation and chronic inflammation
Chronic viral infections often cause dysregulated immune responses characterised by persistent inflammation and immune system exhaustion. Prolonged activation of the immune system can lead to tissue damage, fibrosis, and increased susceptibility to secondary infections. These are serious, and potentially life-threatening symptoms, because chronic inflammation contributes to the development of other health problems, such as cardiovascular disease, diabetes and neurodegenerative disorders.
In short, due to the relationship between viral infections and chronic inflammatory conditions, the presence of any of these viruses is likely to significantly impact a patient’s health, quality of life, and longevity.
Stigma, discrimination, and other impacts
Beyond the biological consequences, chronic viral diseases are often accompanied by stigma, discrimination, and other burdens that affect the quality of life and well-being of affected individuals. Stigma surrounding certain viral infections, such as HIV/AIDS and hepatitis, can lead to social isolation, mental health issues, and barriers to healthcare access. On top of this, the financial burden of chronic viral diseases, which includes the cost of treatment, lost productivity, and reduced earning capacity, further compounds the impact on individuals and their wider communities.
Chronic viral disease therefore represent a significant and often overlooked burden on global health, characterised by diverse manifestations, complex pathogenesis (how a disease develops, progresses, and either persists or is resolved), and profound socio-economic implications.
Treatments and cures for chronic viral disease
Medical science has begun to control a number of acute viral infections, but chronic – or persistent – viral infections remain largely uncontrolled. There are a few success stories however.
Hepatitis C Virus (HCV): Current direct-acting antiviral drugs can cure HCV in over 95% of patients.
Human Immunodeficiency Virus (HIV): While not curable yet, antiretroviral therapy can suppress HIV to undetectable levels.
Hepatitis B Virus (HBV): Current treatments can suppress HBV but not completely eliminate it.
Research is ongoing for more effective therapies to target latent viral reservoirs, and methods for delivering therapeutic agents to all infected cells, including those in anatomically sequestered sites (locations in the body that are difficult to access or reach with treatments due to their physical isolation or protection by anatomical structures.)
One possible approach to this problem could be modelled on current HIV research that employs a “shock-and-kill” strategy. Latency-reversing agents are given to reactivate (“shock”) the latent virus into activity, which can then be targeted for removal by the immune system, or antiviral drugs.
This approach is of interest to us, because Kimer Med’s antivirals selectively target viral dsRNA, a by-product of active viral (lytic) replication, and work in such a way that they bolster the innate immune system to eliminate virally infected cells from the body. Although this approach opens the door to the possibility of successful treatments or a cure for chronic viral disease, there is still more research to be done in this area.
References:
1. https://me-pedia.org/wiki/List_of_chronic_diseases_linked_to_infectious_pathogens
2. https://www.who.int/news-room/fact-sheets/detail/herpes-simplex-virus
3. https://www.cdc.gov/epstein-barr/about-ebv.html
4. https://www.frontiersin.org/journals/public-health/articles/10.3389/fpubh.2021.692226/full