Delete
New Pathogenic Virus Discovered in China

New Pathogenic Virus Discovered in China

The new virus is transmitted through tick bites

Raúl Rivas González

Catedrático de Microbiología. Miembro de la Sociedad Española de Microbiología., Universidad de Salamanca

Martes, 14 de enero 2025, 12:01

We know of more than 200 species of viruses that cause diseases in humans, most of which have an animal origin. Since the late 20th century, at least ten major epidemics or pandemics have been caused by such pathogens, including some coronaviruses, alphaviruses, filoviruses, influenzaviruses, orthopoxviruses, and members of the flavivirus family. Henipaviruses, bunyaviruses, arenaviruses, and other zoonotic viruses have also led to small sporadic outbreaks.

The presence of domestic and wild animal reservoirs, as well as insect and arthropod vectors, significantly complicates the transmission dynamics of zoonotic viruses, making control measures very difficult to implement.

This explains why, globally, around one billion cases of diseases and millions of deaths occur annually due to zoonosis. Moreover, about 60% of emerging infectious diseases reported worldwide have an animal origin. Of the more than 30 new human pathogens detected in the last three decades, 75% are zoonotic.

Fever and Ticks in China

In this context, the continuous emergence and re-emergence of tick-borne diseases pose an increasing threat to human health. For this reason, experts at a sentinel hospital in northeastern China have actively monitored febrile patients with recent tick bites.

Specifically, Chinese scientists conducted metatranscriptomic sequencing of serum samples from 252 febrile patients between May and July 2023. The investigations resulted in the discovery of a human pathogenic virus species: the Xue-Cheng virus (XCV), provisionally named after the native name of Mudanjiang, the city where it was discovered.

The new virus, detected in ticks of the Haemaphysalis concinna and Haemaphysalis japonica species, belongs to the Orthonairovirus genus of the Nairoviridae family. Clinical manifestations in 26 patients ranged from nonspecific acute febrile illnesses to severe conditions requiring hospitalization.

The data obtained by researchers suggest that XCV is a new emerging species of Orthonairovirus transmitted by ticks, which can infect humans asymptomatically or cause febrile to severe illness.

The Threat of Haemaphysalis concinna

The Haemaphysalis concinna tick is a significant species within the community of ectoparasites affecting animals and humans. It is distributed across 34 countries throughout the Eurasian continent, predominantly in China, Russia, and Central Europe. In China alone, Haemaphysalis concinna is reported to transmit at least 22 different pathogens, including the bacteria Anaplasma phagocytophilum, Ehrlichia chaffeensis, Borrelia garinii, Coxiella burnetii, and Rickettsia raoultii, the protozoan Babesia microti, and several virus species, posing a significant threat to human and animal health.

This tick can parasitize more than 100 host species. While adult specimens infest wild and farm animals (cattle, goats, and sheep), larvae and nymphs feed on small rodents, birds, or reptiles. Humans can be attacked by both nymphs and adults. Recently, new human pathogenic Orthonairoviruses, such as the Wetlands virus (WELV), have been isolated from Haemaphysalis concinna.

A Formidable Genus

Currently, there are 51 distinct viruses assigned to the Orthonairovirus genus. They typically infect certain ticks of the Argasidae or Ixodidae families, which transmit them to small vertebrates (birds and mammals). In turn, these serve as sources of infection for the ticks. Some Orthonairoviruses are transmitted transovarially in ticks.

The human Orthonairovirus with the greatest impact on public health is the Crimean-Congo hemorrhagic fever virus (CCHFV), which is tick-borne and endemic in much of Asia, Africa, and southern and eastern Europe, where it causes often severe and frequently fatal viral hemorrhagic fever.

Other viruses that occasionally cause diseases in humans include the Aigai virus (AIGV), which causes febrile illness and viral hemorrhagic fever; the Erve virus (ERVEV), which causes thunderclap headache; and the Issyk-kul (ISKV), Kasokero (KASV), Soldado (SOLV), Dugbe (DUGV), Sōnglǐng (SGLV), Tamdy, Yezo, and Tǎchéng 1 tick viruses, which cause febrile illness.

From a veterinary perspective, the most relevant Orthonairovirus is the Nairobi sheep disease virus (NSDV). In humans, it causes febrile illness, and in Africa and India, it leads to lethal hemorrhagic gastroenteritis in small ruminants.

So far, the fatality rate of the Xue-Cheng virus (XCV) in humans is unknown, but the virus that causes Crimean-Congo hemorrhagic fever can reach up to 40%, so the discovery of the new pathogen should be approached with great caution. The growing burden of tick-borne Orthonairovirus infections is becoming a global public health concern.

This article was published in The Conversation.

Publicidad

Publicidad

Publicidad

Publicidad

Esta funcionalidad es exclusiva para registrados.

Reporta un error en esta noticia

* Campos obligatorios

todoalicante New Pathogenic Virus Discovered in China