Impact Of Mojiang Henipavirus On Health

Introduction

The virus known as Mojiang henipavirus, or MŠjiāng virus (MojV), belongs to the Paramyxoviridae family of viruses. Phylogenetic analysis classifies the Mòjiāng virus as a henipa-like virus within the genus Henipavirus. Antibodies generated against the glycoproteins of the Mojiang henipavirus are serologically unique from toher henipaviruses.¹

 The genus Henipavirus is made up of three known species - the Hendra, Nipah, and Cedar viruses - and nineteen newly discovered species, including Bat Paramyxovirus, the first fully sequenced virus. The zoonotic pathogens Nipah and Hendra viruses are linked to lethal neurological and respiratory diseases in humans, horses, and pigs. Fruit bats are the known natural reservoirs for henipaviruses, with no reports of these viruses existing in other wild animals. However, a new henipa-like virus was discovered in rats in China, called Mojiang paramyxovirus (MojV).²

Mojiang virus and Langya virus are zoonotic pathogens that cause fever and respiratory distress in humans, primarily found in the Yunnan, Henan, and Shandong provinces of China. 

Hendra virus and Nipah virus are zoonotic pathogens that cause severe acute respiratory distress and high mortality in humans, primarily located in Australia, Malaysia, India, and Bangladesh.³

History

In the spring of 2012, three miners working in an abandoned copper mine in Mojiang Hani Autonomous County, south China tragically died from pneumonia. Samples of these cases were sent to the Wuhan Institute of Virology r where Dr. Shi Zhengli and her colleagues conducted PCR testing. The results confirmed that the samples were neither SARS-CoV2 nor the bat coronavirus Rp3.

Viral RNA and infectious viruses were studied in several cave-dwelling mammal species, including Rhinolophus ferrumequinum (greater horseshoe bats), Rattus flavipectus (rats), and Crocidura dracula (shrews). Among the 38 sequence reads obtained, a strong relationships to Henipavirus genus members was observed. Only four R. flavipectus samples that were cultivated in Vero E6, BHK-21, and HEp-2 cells yielded infectious viruses.

The full range of mammalian hosts susceptible to the Màjiāng virus remains unknown, and no cases of person-to-person transmission have been reported. While henipaviruses such as Hendra, Nipah, Cedar, Kumasi, and Madagscar are predominantly found in chiropterans, mainly Pteropus species (fruit bats), MojV is unique among henipaviruses in that it is primarily associated with rodents.⁴

Virology

The cell surface receptor of the Mojiāng virus is still unidentified. Unlike all other known members of the Henipavirus family, the Mòjiāng virus does not bind Ephrin B2/B3, which are common receptors for henipaviruses. Additionally, in cell culture studies, the Mòjiāng viral attachment glycoprotein (MojV-G) does not bind sialic acid or CD150, two major paramyxovirus receptors, and lacks an Ephrin B2/B3 binding site. MojV-Gexhibits over 50% sequence divergence from HeV-G, making it the most diverged gene within the Henipavirus genus. This divergence is so significant that MojV-G and HNV-G are as different from one another as the morbillivirus attachment glycoprotein is from HNV-G.¹

Mode of transmission

Henipavirus is primarily found in Pteropid fruit bats, commonly known as flying foxes, which serve as their natural reservoir. Humans can contract the Hendra virus by coming into close contact with infected horses, including the exposure to the horse’s bodily fluids, or their tissues. Horses become infected when they come into touch with bat urine. The Hendra virus does not spread directly from bats to humans or from one person to another.

The Nipah virus can be transmitted through direct contact with infected pigs or bats. Ingesting date palm sap or fallen fruit tainted with bat excrement can also lead to infection. Human-to-human transmission has also been reported via respiratory droplets, particularly during intimate contact. Cultural and medical caregiving practices that involve close interaction with infected patients can also spread the virus.

Initial sampling of small wild mammals found that the Langya virus was primarily found in shrews, with 71 out of 262 (26%) shrews of the speciesCrocidura lasiura and Crocidura shantungensis testing positive. To conclusively identify the vulnerable species, natural animal reservoir(s), and human transmission pathways, further research is required. The Langya virus does not appear to be spread from person to person based on preliminary data.⁵

Pathological features

Gross discoveries

The lungs are heavy and show signs of edema, bleeding, and congestion in fatal instances.

Microscopic discoveries

Histopathologic involvement of the respiratory and central neurological systems Endothelial cell injury, thrombosis, vasculitis, and development of syncytial cells multinucleated large cells in the lung, brain, and other organs having inclusions in the cytoplasm and nucleus.

Features of Immunohistochemical

IHC reveals the widespread presence of henipavirus antigens in a variety of parenchymal cells as well as in the endothelium and smooth muscle cells of blood vessels.

Features of ultrastructure

Pleomorphic virus particles consist of envelope-encased helical nucleocapsids.⁶

Incubation period 

The incubation period is 5 to 16 days and can extend to 2 months.

Clinical manifestation

An intense influenza-like sickness accompanied by headache, fever, myalgias, and dizziness can be brought on by infections with the Hendra or Nipah viruses. Severe encephalitis including convulsions, aberrant reflexes, respiratory problems, and coma are possible outcomes of the illness. Months or years following an acute disease can see a relapse or late-onset encephalitis. The Hendra virus has a 57% case-fatality ratio; of the 7 recorded human cases, 4 resulted in death. Infection with the Nipah virus has a case-fatality ratio of 40%–70%, although in certain human epidemics, it has reached 100%.

Clinical symptoms that are not specific have been described in the majority of the 35 cases of Langya virus infection that are known to exist (e.g., anorexia, cough, lethargy, fever, headache, myalgia, nausea, vomiting). As of yet, no Langya virus-related deaths have been reported.⁵

Morbidity and mortality 

Approximately 30% to 40% of Nipah cases result in death, which is linked to the fast development of severe neurologic symptoms.

Of the seven known cases of Hendra, four resulted in death.

Vulnerable population

 The method of exposure has a major impact on the patient's demographics; in most cases, occupational

No obvious racial or gender preference.⁶

Diagnosis

A variety of assays are used in the laboratory to make the diagnosis, such as virus isolation from CSF or throat swabs, reverse transcription PCR of serum, CSF, or CSF, and ELISA of serum or cerebrospinal fluid (CSF). Tests on specimens from patients suspected of having a hepatitis virus infection can be conducted by the Centers for Disease Control and Prevention (CDC). Make an appointment for a clinical consultation with the state or local health department before sending specimens to the CDC.⁵

Diffrential diagnosis

Additional viral causes of giant cell pneumonia, encephalitis, and diffuse alveolar destruction in addition to noninfectious causes of the same.⁶

Treatment

Henipavirus infections do not currently have a particular antiviral treatment available. Supportive care and problem management are the two main components of therapy. Although ribavirin has demonstrated efficacy in vitro, its potential clinical utility remains unclear. In Australia, a monoclonal serotherapy has been suggested for Hendra.⁵

Prevention

Visitors should stay away from sick horses, pigs, and bats as well as their excretions. It is not advisable for travelers to eat fallen fruit or uncooked date palm sap or items manufactured from it. There are presently no licensed vaccines for humans, however, a Hendra virus vaccine for horses has been approved in Australia and may one day help prevent Henipavirus infections in humans.⁵

WHO response

WHO is providing technical assistance to impacted and vulnerable nations on managing MojV virus outbreaks and averting future ones.

By thoroughly cleaning and peeling fruits before consuming them, one can reduce the chance of worldwide transmission via fruits or fruit derivatives (like raw date palm juice) contaminated with the urine or saliva of infected fruit bats. Fruit-bearing evidence of bat bites ought to be thrown away.

FAQ’s

When should I visit my medical professional?

If you believe you may have been exposed to the Mojiang virus and you are experiencing symptoms, see a healthcare professional consult with your medical professional if you are living in places where it is prevalent or if you work with species that are prone to henipaviruses, such as shrews.

When is a good time to visit the ER?

MojV symptoms are generally mild. However, you should visit the emergency department if you experience any of the following:

• Elevated fever (over 40 degrees Celsius/103 degrees Fahrenheit)
• Trouble breathing
• Persistent pain in your abdomen or chest that does not go away
• Seizures
• Lips, nails, or skin that is bluish (cyanosis)

Summary

The Mojiang virus has had significant implications for public health, highlighting the potential risks posed by novel pathogens. Its emergence underscores the importance of robust surveillance systems and rapid response mechanisms to mitigate future outbreaks. 

While the exact origins and characteristics of the virus remain unclear, its impact on health has been substantial, with reported cases exhibiting a range of symptoms from mild to severe. 

The virus has prompted intensified research efforts into its transmission dynamics, pathogenesis, and potential treatments or vaccines. Furthermore, the global response to the Mojiang virus has emphasized the necessity of international collaboration and information sharing in combating emerging infectious diseases. 

Moving forward, continued vigilance and investment in preparedness measures will be essential to safeguarding global health security against similar threats in the future.