Team:Moscow City/Description

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Saving horse's lifes
Equine herpesvirus outbreaks keep the horse-owning community at bay

The Russian iGEM team is struggling with the increasing cases of EHV in the world and is developed rapid diagnostic test

Equine herpesviruses are DNA viruses
Almost all horses have been infected with the viruses and have most of the times no serious side effects. It is currently unknown what causes some infected horses to develop the serious forms that may be fatal. 

EHV stands for equine herpes virus. This is a family of viruses which are named by numbers such as EHV 1, 2, 3, 4 and 5. EHV 1, 3, and 4 pose the most serious health risks for domestic horses.

In our project, we detect EHV-1 and EHV-4 RNA to track the active virus [7].

For more information check our EHV page

As humanity struggles with a single disease that claims the lives of millions, a contagious and dangerous disease is spreading among horses caused by an Equine Herpes Virus (EHV).
Up to 80% of horses are infected, and up to 10% of cases are fatal[1].

Сompetitions are canceled, stables are quarantined, and mass abortions of breeding horses occur, because of equine herpes virus outbreaks.

Significant outbreak of rhinopneumonia happened at the International Equestrian Competitions in Valencia in February. As a result, about 800 horses were isolated, 18 died[2].

News about outbreaks comes from all over the world, from Canada to Brazil [3,4]. The flashes are now silent, then rapidly advancing.

While for humans, methods of treating viral and herpesvirus diseases are known and studied, this is not the case for horses and farm animals. So after diving into the problem, asking scientists, veterinarians, and horse lovers, we decided to make the life of horses better.
Why did we choose herpes virus diseases for our project?
A girl from our team personally experienced rhinopneumonia, an EHV-induced disease. From her own experience, she found out how much the situation in the diagnosis and treatment of horses is running.

Then we interviewed veterinarians and horse owners. Communication with scientists and veterinarians showed us the lack of modern systems for treating and diagnosing animals. Animals are our four-legged friends that we need to take care of as ourselves. Humanity is indebted to horses that have advanced agriculture and the economy. That is why the latest developments in therapy, synthetic biology, and medicine should be applied to the treatment of animals.
Our work is also inspired by COVID-19
The nucleic acid of the coronavirus is a single-stranded RNA [5]. Therefore, since the method developed by us works with RNA, it can also be used for the early diagnosis of coronavirus infections.

The troubles from both human coronavirus and equine herpesvirus are similar. One of the main dangers of SARS-CoV-2 is the asymptomatic period during incubation of the virus (2-14 days) [6]. At this time, the virus can be transmitted to other people. In herpesviruses, symptoms within two weeks after infection may also be ambiguous for an accurate diagnosis, or as in the case of neurologic herpesvirus (EHM) - absent [7]. Rapid and early detection of the virus is necessary for contact tracing and enhanced surveillance. This can be achieved only if the diagnosis is established.

The issue of vaccination is also tricky for both diseases. For Covid-19: there is a shortage of vaccines on the market; it is difficult to vaccinate everyone. In the case of EHV, existing vaccines are outdated, do not protect completely. This also leads to the fact that the best way not to get infected is to observe preventive measures - isolation [7].

During the pandemic in 2020 and 2021, the demand for laboratory equipment and qualified employees increased [8]. This led to a shortage of materials and increased sample analysis time. As a result, new methods are needed to respond quickly to such pandemics.
We want to improve the lives of horses.
To do this, we will do the following:
To prevent the disease → prophylaxy and vaccination
Identify at an early stage → diagnosis
To cope with the leak → treatment and therapy
What diseases does the herpes virus cause?
The clinical signs depend on the type of virus.
There are 5 of them in total, but EHV-1 and EHV-4 pose the greatest threat [9].
Why are equine herpesviruses dangerous?
The spread of EHV [10]
Deaths of horses
This year, a significant outbreak of rhinopneumonia caused by the equine herpes virus happened at the International Equestrian Competitions in Valencia in February.
Canceled contest
News about outbreaks comes from all over the world, from Yakutia to South America. The flashes are now silent, then rapidly advancing.
Infected countries
Equine herpesvirus is the most contagious equine virus. The presence of just one carrier horse is enough to infect up to 80% of the rest.
The virus is transmitted by airborne droplets
By discharge from the nose and mouth that spreads in the wind or remains on the clothing.
And by direct contact of horses through sneezing or snorting
Sick horses need
to be isolated
The only viable way to prevent the spread that has already begun is complete premature isolation. Everything that could get the saliva or other fluids of the horse should be disinfected.
Vaccines don't provide
the protection
The issue of vaccines is ambiguous. A vaccinated horse will tolerate diseases more easily, but there is a high risk of becoming a carrier and still having an outbreak.
Let’s start with detection

When we analyzed the problem, we decided to create a fast and mobile test system based on CRISPR-Cas. It detects herpesvirus by its RNA (but the virus is dsDNA).

We use deadCas13 protein, connected by a linker with two halves of reporter protein - beta-lactamase. Two deadCas13 proteins are directed by gRNA to the RNA of the virus. When the distance between two Cas proteins is correctly selected, two beta-lactamase proteins can fuse into a functional protein that destroys nitrocefin. The solution’s color changes from yellow to red. To make beta-lactamase fusion more effective, we decided to add intein to beta-lactamase halves. Later intein doesn’t interfere in the main process, while N- and C- parts of beta-lactamase fuse into a functional protein.

The paper test will have detection and control stripes. To avoid false-positive results we use two guide RNAs. With one guide RNA reporter protein won’t become functional. We are willing to create a fast and mobile test system that won’t require any special skills to use it. Horse owners will be able to detect herpesvirus with our test using saliva. Only effective and fast diagnosis can prevent the disease from spreading. Horse owners should know as early as possible about the virus to isolate and cure horses.

We plan to adapt this system to detecting other diseases - both animals’ and humans’.
Mobile testing
is more useful
  • Isolate the horse
  • Not to be confused with the flu, allergies, arteritis
  • Use in competitions, in the steppes, stables
  • Identify the virus strain-make it easier to choose a medicine
1 - Characterization of high virulent strains of equine rhinopneumonitis virus
2 - About EHV outbreaks:
3 - EHV, Canada
4 - EHV, Brazil
5 - On the origin and continuing evolution of SARS-CoV-2
6 - Syangtan G, Bista S, Dawadi P, et al. Asymptomatic SARS-CoV-2 Carriers: A Systematic Review and Meta-Analysis. Front Public Health. 2021;8:587374. Published 2021 Jan 20. doi:10.3389/fpubh.2020.587374
7 - FAQ about EHV
8 - COVID-19: Overcoming supply shortages for diagnostic testing:
9 - Equine herpesviruses 1 (EHV-1) and 4 (EHV-4) – epidemiology, disease and immunoprophylaxis: A brief review
10 - EHV timeline