Norovirus causes a series of camouflage symptoms, such as nightmares, and hate infections have been prevalent this winter. The so -called flu (not related to influenza, but suddenly curses victims with diarrhea and vomiting for 1-3 days.
However, unlike other ordinary infections, such as seasonal flu and cobid, there is no vaccine that helps people avoid side jobs by Norovirus, a notorious and elastic virus that is difficult to die with ordinary alcohol -based disinfectants. Vaccine developers have been working for a long time to make vaccines. However, in the United States, there are some scientific barriers that are not effective enough to be approved, but researchers hope that one approach is soon to meet the challenge and raise the immune system for unpleasant infections and provide effective tools for those who are self -immune.
What is Norovirus?
To support science journalism
If you are enjoying this article, support the award -winning journalism. accession. By purchasing subscriptions, it will help you to ensure the future of influential stories about finding the world today and the idea of an influential story about ideas.
Norovirus is responsible for more than half of the case of American food -based diseases. The virus can survive for up to two weeks on the surface, and face the general hand disinfectant and flourish and torn through an environment such as a cruise ship and a restaurant. Typical symptoms of infections include diarrhea, vomiting, zones and abdominal pain. People can also experience heat, headaches and physical pain. If vomiting and diarrhea are serious, the risk of serious dehydration increases.
Data in the disease control and prevention center for the occurrence of noroviruses is quite limited. Only 14 states include the system of monitoring networks on infections. Nevertheless, this statistical paint picture is dark. The report was found that 1,078 people were suspected or confirmed from August 1, 2024 to January 15, 2025 to January 15, 2025. When the network is set.
Children and people aged 65 or older are particularly vulnerable to serious diseases. Every year, viruses cause more than 2 million outpatient clinic visits, and for young children, they kill about 900 people and most of them over 65 years old. Infection is highly contagious, causing great onset, and strikes these vulnerable groups, but for most people, symptoms last a few days. Ming Tan, a scientific researcher at the Cincinnati Children’s Medical Center, said that the severity of the severity of the disease suggests a difficult situation for the vaccine manufacturer.
Tan says, “Some people don’t see it as a very important disease, and others say it’s terrible because many people can hurt many people in certain intimate environments.
Challenge for vaccine manufacturers
Viruses have some characteristics that are difficult for vaccine developers. First, like influenza, “norovirus” is a virus group that is actually divided into 10 larger classes consisting of 10 so -called genetic types. Like the flu, the immune system trained to recognize one various noroviruses cannot necessarily protect other noroviruses. And because the dominant strain often come and go every two to four years, it is difficult for the immune system to maintain. (This year and last year’s examples were mainly caused by the tension of GII.17, and the previous season was led by the nickname of Sydney.)
Doran Fink, a doctor and vaccine scientist, said, “There are dozens of genotypes of noroviruses that can cause diseases in humans, and each of these gene type has a slightly different protein shell that needs a slightly different immune response. Biotech Company Moderna is leading the development of Norovirus vaccines.
Another challenge is that the Norovirus causes scientists to call it mucous membranes or mucosal infections, in which case it is the topical infection of the intestinal surface tissue. (The flu is local mucosal infection in the respiratory tissue.)
This topical virus is more difficult for the body to remember and fight compared to the whole body infection that affects the entire body and generally strong and long -lasting immune response. Lijuan Yuan, a virus immunologist of Virginia Tech, said, “Mucosal immunity is short, unlike systemic immunity. The injected vaccine pointed out that it is not a mucous membrane, not a mucous membrane. This disconnection increases the likelihood of protection of severe diseases without the injected vaccine for mucosal infections.
Norovirus is also difficult to work in the laboratory. Preliminary vaccine experiments usually require animal models, but researchers do not have a good model for noroviruses. Because human noroviruses do not easily infect animals, animal-specific noroviruses cause very different symptoms. Yuan pointed out that Norovirus could not grow well in cells.
In the pipeline
Despite many obstacles, scientists are conducting clinical trials to test six other vaccine candidates. All of them are targeted with primary surface proteins (or capsid proteins), except for norovirus molecules, but they use various approaches with their own strengths and weaknesses, respectively.
In one approach, scientists produce a lot of so -called capsid proteins. The protein then voluntarily forms an empty structure in the same form as the virus. When this empty shell, called a virus, is injected into a person, the body reacts like the actual and trains the immune system. But creating particles like viruses takes a lot of time, TAN says. And the vaccine had appropriate results in adult tests, but it rarely helped to protect children, and this vulnerable population suggests that other vaccines may be needed.
The second approach is generally called adeno virus, usually a light respiratory virus, which can not be replicated and provides the ability to produce a target norovirus protein. Adenoviruses are packed with oral vaccines, making it much easier to administer than injections, and can train the mucosal immune system directly. But the protection rate is still a bit low, TAN says.
The third approach uses the same mRNA technology as used to create a covid vaccine. Genetic information about norovirus proteins is injected into the vaccine audience to induce an immune response. This method is simpler to run and can be updated more easily when other norovirus strains are dominant, Fink says. Moderna’s team designed the MRNA Norovirus vaccine, and the company is now recruiting people and testing how much it protects it. Through this, scientists can compare mRNA technology to particles such as viruses, and have a disappointment of the researchers. “Regardless of whether it will have a better effect, we must still wait. [and see]TAN, which is not related to these candidates, says.
Either way to make a vaccine through the exam, you may not be able to get the state of the flu prevention. Norovirus vaccines will be provided first to people over 65 years of age or older, given that norovirus infection can be much worse in these groups, Fink says. Perhaps it will be provided for annual doses with the peak period of the norovirus between the northern hemisphere to November and April. Perhaps even those who will be on the cruise or those who are expected to be exposed to viruses can choose the dose. But TAN is not sure that a healthy adult is very interested in the norovirus vaccine.
Fink says that even if the vaccine is not completely protected, it is still worth using the vaccine as a prevention option. “If you get a norovirus, if you can change the burden of a very gentle disease, I think it’s a big success.”
