Developing A Vaccine For African Swine Fever Vaccine
![]() |
Swine Fever Vaccine |
African swine fever is a lethal pig disease that has been spreading rapidly across many countries. Scientists and researchers have been working tirelessly to develop an effective vaccine that can help control this disease. In this article, we discuss the progress being made on an African swine fever vaccine.
The Disease and its Impact
African swine fever is a viral hemorrhagic disease of domestic and wild pigs
that was first reported in Africa in the early 1900s. Since then, it has spread
to Europe and Asia. The virus that causes African swine fever is highly
contagious and can spread through direct contact between infected and healthy
pigs as well as indirectly through contaminated feed and contact with fomites
like vehicles, clothes and shoes. The mortality rate in infected pigs
approaches 100%.
Once an outbreak occurs, it is very difficult to control the spread of the
disease. Countries that experience outbreaks face tremendous economic losses
due to death of pigs and cost of controlling the spread and recovering from the
outbreak. For example, China reported losing over a million pigs to African
swine fever in 2018 alone. With increasing globalization and movement of people
and goods, the spread of this disease to other regions is a major concern.
Developing an effective vaccine is crucial to help control African swine fever.
Challenges of Vaccine Development
Developing a Swine
Fever Vaccines against African
swine fever virus is challenging for several reasons. The virus lacks effective
immunogenic genes and has complex mechanisms to evade the host immune system.
It also exhibits considerable genetic diversity which complicates vaccine
design. Furthermore, there is no small animal model for African swine fever
virus pathogenesis and immune response studies. Researchers need to rely solely
on expensive pig trials for vaccine testing. These challenges have
significantly slowed down the pace of African swine fever vaccine development.
Promising Vaccine Candidates
Despite the challenges, progress is being made on development of African swine
fever virus vaccines. Several groups across Europe and China are pursuing
different vaccine strategies:
- Deletion Mutants: Scientists at The Pirbright Institute in UK have developed
live attenuated vaccines by deleting immunoregulatory genes from the virus
genome. Pigs vaccinated with these mutants displayed some level of protection
upon challenge.
- Virus-Like Particles: Researchers at University of Bath constructed
virus-like particles by expressing structural proteins of African swine fever
virus. These sub-unit vaccines have shown protection in animal trials.
- DNA Vaccines: Groups in Spain and China have designed DNA vaccines containing
immunogenic genes from African swine fever virus. Pigs inoculated with these
vaccines produced specific antibodies and T-cell responses.
- Vector Vaccines: Recombinant vectors like vaccinia virus and adenovirus have
been tried to deliver African swine fever virus antigens. One such vaccine
developed by Harbin Veterinary Research Institute in China was partially
protective in pigs.
- Novel Delivery Systems: Novel delivery systems like polymicrobial vaccines
using Salmonella or plants expressing viral antigens are also being examined to
enhance immunogenicity.
Regulatory Approval and Commercialization
While the above-mentioned vaccine candidates seem promising, there is still a
long way to go before commercial availability. Most vaccines will need to
undergo rigorous testing through multiple pig trials under laboratory and field
conditions to prove safety and efficacy as per regulatory standards.
Large-scale manufacturing processes will have to be established to produce
sufficient vaccine doses economically.
If future trials continue to show good protection, regulatory authorities may
consider conditional licensure of African swine fever vaccines. However, full
commercial rollout may still take 5-10 years given the complexity of the
disease. International cooperation across research groups and regulators will
also be important to standardize testing protocols and facilitate approval
process. Overall, an effective African swine fever vaccine could be a game
changer for the global pig industry worth billions of dollars.
Concluding Remarks
To summarize, African swine fever is a challenging disease to control due to
lack of vaccination. Researchers have made progress in designing various
vaccine candidates using different strategies over past few years. Ongoing gene
deletion mutants and subunit vaccines show most promise based on preliminary
results. However, much more testing is still needed to prove efficacy under
field conditions. If successfully developed, a vaccine could greatly minimize losses
caused by this lethal pig disease worldwide. With sustained efforts, the goal
of an approved African swine fever vaccine seems achievable in the near future.
For
more insights, read- https://www.newsstatix.com/swine-fever-vaccine-trends-size-and-share-analysis/
Comments
Post a Comment