What Is the New Langya Virus, and Should We Be Worried?

The following essay is covered in The Conversation, an online publication.

35 people are thought to have been affected by Langya henipaviruses over the course of two years in China.

There are two viruses that cause disease in humans. We don't know if LayV spreads from human to human

We know what we know.

How sick are people getting?

The first detection of this new virus was made by researchers in China. The researchers looked for the virus in other people after identifying it.

We don't know how long the patients were unwell but the symptoms were mostly mild.

There were potentially more serious problems for a smaller proportion. There were no reports of the severity of the abnormality, the need for hospitalisation, or the death of a case.

Where did this virus come from?

The authors looked into the possibility of domestic or wild animals being the source of the disease. There was more evidence that wild shrews were harbouring the virus than a small number of goats and dogs.

It's possible that humans caught the virus from wildhrews.

Does this virus actually cause this disease?

This new virus was found using a modern technique called metagenomic analysis. Researchers sequence all genetic material and then discard the "known" sequence to look for "unknown" ones that may be related to a new virus.

The question of whether a particular virus causes the disease is being asked.

Koch's postulates have traditionally been used to determine the cause of disease.

• It needs to be found in people who have the disease and not in people who don't.

• It needs to be isolated from people with the disease.

• If given to a healthy person, the disease must come from the person with the disease.

• It needs to be re-isolated from the healthy person after they get sick.

The relevance of these criteria in the modern era has been questioned by the authors.

There was evidence that 14 people's immune systems had responded to the virus, and that people who were more unwell had more virus.

What can we learn from related viruses?

The new virus is a close cousin of two other viruses that are important in humans. The fictional MEV-1 virus was inspired by this family of viruses.

The deaths of 14 horses and the trainer were caused by the Hendra virus.

Many horse infections have been reported in northern New South Wales, and are thought to be caused by flying fox infections.

There have been at least seven human cases of Hendra virus reported in Australia.

The NIPah virus is more common in Bangladesh than anywhere else.

Mild to fatal encephalitis can be the result of an infection.

There was a pig outbreak in Malaysia and Singapore. It is thought that the recent outbreak has been due to contaminated food.

The Nipah virus seems to be transmitted from person to person.

What do we need to find out next?

The current reported cases are likely to be the beginning of a larger problem.

There is no evidence that the virus can spread from one person to another.

How severe the infection can be, how it spreads, and how widespread it might be are some of the questions that need to be answered.

The conversation published this article. The original article is worth a read.