Recently, onset of a new virus has caused yet another matter of concern for the World Health. It’s a tick-borne virus that has already killed seven people in China and infected sixty others. Earlier this year more than 37 people contracted the SFTS Virus in East China’s Jiangsu Province. Twenty-three people later were found to be infected in China’s Anhui province according to the state-run Global Times media report. Seven people have died in Anhui and East China’s Zhejiang.
Symptoms
The clinical condition it causes is known to be severe fever with thrombocytopenia syndrome. SFTS has a fatality rate of 12% and 30% in some areas.
A woman from the capital of Jiangsu, Nanjing who has been a victim to the tick-borne virus has had suffered symptoms like fever, coughing, decline of leukocyte and blood platelet.
- Fever
- Vomiting
- Diarrhea
- Multiple organ failure
- Thrombocytopenia (low platelet count)
- Leukopenia (low white blood cell count)
- Increased liver enzyme level
Epidemiology
The tic borne disease have been found in the Chinese provinces of Anhui, Henan, Hubei, Jiangsu, Liaoning and Shandong. This virus occurs in mostly rural areas, from March to November and majority cases are detected from April to July. The virus has been found in South Korea, Japan, Vietnam and Taiwan.
History
As many might think this SFTS Virus is however not a new virus. The virus originated in the Dabie Mountains in Central China between 1918 and 1995. Previously China has isolated pathogens of the virus in 2011. This virus belongs to the Phenuiviridae family and Bunyavirus order. It is also known as the Dabie Banda virus. Xue-jie Yu and colleagues isolated the SFTS virus from SFTS patient’s blood back in 2009. It is a growing infectious disease that was first found in Northeast and Central China in 2009. It has now been found in Japan, South Korea, Vietnam and Taiwan in 2015.
Evolution
Five genotypes ranging from A-E have been identified. Infections from China can be grouped into all five genotypes while isolates from South Korea lie in three types A, D and E. Japan has only the type E. Among the Bunyaviruses it is more closely related to the Uukuniemi virus serogroup than to the Sand-fly fever group. It is a member of the Bhanja virus serocomplex.
Transmission
The virologists proclaim that the infection can be or may be passed on to humans in the form of ticks and is possible for transmission between humans. Sheng Jifang, who is a doctor from the first affiliated hospital under Zhejiang University said that the human to human transmission possibility cannot be ignored as patients can pass the virus to other via blood or mucous. Tick bite however is the major transmission path and can be avoided and not frowned upon until and unless people remain cautious.
Life Cycle
Dabie Banda virus is a tick-borne virus. Tick borne virus transmission is not clear whether it can be transmitted by other blood sucking arthropods. It can infect many mammalian hosts, including cats, mice, hedgehogs, brushtail possums, yaks and weasels. Humans are more of the accidental’s hosts, and do not affect the life cycle of SFTSV. SFTSV has been detected from the ixodid tick, Haemaphysalis longicornis, Ixodes nipponensis, Amblyomma testudinarium and Rhipicephalus microplus. In addition to the tick bite, it can be transmitted from person to person through contact with blood or mucus of an infected person.
Genome
There are three segments of its genome – Large, Medium and small. Five proteins have been recognized – an RNA dependent RNA polymerase (RdRp), a glycoprotein N, a glycoprotein C, a nuclear protein and a non-structural protein. The Large segment encodes the RNA polymerase with 2084 amino acid residues. The Medium segment encodes one open reading frame encoding 1073 amino acid precursors of Glycoproteins N and C. The Small segment has 1746 nucleotides of ambisense RNA encoding two proteins, the N and NSs proteins. These all lie in opposite orientations and are separated by 54 nucleotide intergenic region.
Treatment
A vaccine to treat the disease is yet to be developed. An anti-viral drug called Ribavirin is known to be effective in treating the illness. In order to avoid the illness, various government authorities including China’s Centers for Disease Control and Prevention urges the public to avoid wearing shorts while walking through grass, woods and any other environment where ticks are likely to live.