New Langya Virus: Should You Worry?

When and How Was the Langya Virus Identified?

In August 2022, scientists in China published a letter in the New England Journal of Medicine titled, “A Zoonotic Henipavirus in Febrile Patients in China.” They discuss the new Langya henipavirus discovered during routine surveillance of patients with a fever who have regular contact with animals.

Most of the patients infected with LayV were farmers. The researchers used metagenomic analysis to figure out that they were dealing with a new virus. Metagenomic analysis is a genetic analysis conducted on samples retrieved from the environment or, in this case, patients. 

In the article, the authors elaborate that the virus is related to the Mojiang henipavirus, another virus from the Paramyxoviridae family [1]. 

How Does New Langya Spread?

While LayV antibodies were discovered in a few goats and dogs, wild shrews are the more probable vectors transmitting the Langya virus to humans. So far, the Langya virus has not been shown to spread from human to human [1]. 

Shrews are small, furry mammals with a snout and long whiskers — almost mole or rodent-like. They have large front teeth and give off a foul smell to ward off predators. Shrews (family Soricidae) are found worldwide, including North America, South America, Europe, Asia, Africa, and other locations. They are scrappy animals that can survive in various habitats and are active all year long [3].

What Are The Symptoms of New Langya Infection?

The LayV virus belongs to the Paramyxoviridae family and causes respiratory symptoms. Langya virus symptoms include: 

• Fever
• Cough
• Headaches
• Nausea
• Vomiting 
• Muscle aches

Even though most symptoms were mild, some people developed impaired kidney and liver functioning and blood cell abnormalities. So far,  LayV cases have not been fatal [1].

Epidemiology of LayV

Langya has been reported in the Shandong and Henan provinces in Eastern China. Most people infected with LayV are farmers in frequent contact with animals. 

The Dangers of Zoonotic Viruses

60% of infectious diseases in humans and 75% of all emerging diseases are zoonotic — diseases that transmit from animals to humans [4]. Zoonoses cause almost one billion disease cases and millions of deaths each year [5]. Many of these deadly diseases start as animal-to-animal transmissions.  

Zoonotic spillovers are the main source of new infections. At some point, a pathogen mutates and begins to infect humans. Take the case of a virus that infected chimpanzees in the past and later evolved into HIV ( human immunodeficiency virus) in humans. Now, HIV almost exclusively spreads from human to human. Other well-known zoonoses include ebola, dengue, and Lyme disease. 

Emerging viruses have the potential to mutate, spillover to humans, and cause widespread outbreaks. In particular, viruses that lead to respiratory symptoms can ‘go viral’ and cause outbreaks, epidemics, and even a pandemic like the SARS-CoV-2 pandemic.

So, it’s essential that we do not ignore the new Langya virus because it is not contagious right now. Vigilance, surveillance, and research are important [9]. Also, continuing education for clinicians on the frontlines can help them identify early signs of new diseases and help prevent public health crises. 

About Nipah and Hendra Viruses

Nipah Virus

The Nipah virus (NiV) is a zoonotic virus (that can be transmitted from animals to humans). Fruit bats are the natural hosts for the Nipah virus, which has a case fatality rate of 40% to as high as 75%. This danger to human life is why the Nipah virus is on WHO’s list of priority diseases for urgent research and development [2]. 

What’s interesting is that the story of Nipah started much like the Langya virus. According to WHO, the Nipah virus was first identified in Malaysia. The human infections at the time were due to direct contact with infected animals (pigs). Eventually, later outbreaks in Bangladesh and India saw the Nipah virus spread from person to person [6]. 

This is why keeping an eye on emerging zoonotic viruses and closely tracking infections is important. 

Hendra Virus

The henipavirus Hendra is another member of the Paramyxoviridae family. It was first isolated in 1994 from an outbreak in horses and humans in Hendra, Australia. The natural reservoir is flying foxes. Hendra virus infections in humans are extremely rare, and people can get infected only through intermediate hosts like horses. However, the Hendra virus disease is dangerous as it can be fatal. Symptoms include inflammation in the brain, causing meningitis or encephalitis, and even convulsions and coma [7,8].