Recent Ancestry of Kyasanur Forest Disease Virus

Mehla, Rajeev; Kumar, Sandeep; Yadav, Pragya D; Barde, Pradip V; Yergolkar, Prasanna N.; Erickson, Bobbie R.; Carroll, Serena A.; Mishra, Akhilesh C.; Nichol, Stuart T.; Mourya, Devendra T.

doi:10.3201/eid1509.080759

Cited by 86 publications

(88 citation statements)

References 21 publications

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“…Both found that the three genome segments undergo roughly 10 À4 changes per nucleotide per year, or about two base changes per year for the entire genome. Carroll et al observed that the rate of evolution of CCHFV was somewhat slower than that reported for the mosquito-borne bunyavirus, Rift Valley fever virus and the tick-borne flavivirus, Kyasanur Forest disease virus (Bird et al, 2008;Mehla et al, 2009), but the differences were modest. Because the evolutionary rate of a virus is simply a way of measuring its genetic diversity, both groups reported that the CCHFV M segment was evolving more rapidly than the S or L segment.…”

Section: Genetic Driftmentioning

confidence: 75%

Crimean-Congo hemorrhagic fever: History, epidemiology, pathogenesis, clinical syndrome and genetic diversity

et al. 2013

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Bente, Dennis A.; Forrester, Naomi L.; Watts, Douglas M.; McAuley, Alexander J.; Whitehouse, Chris A.; and Bray, Mike, "CrimeanCongo hemorrhagic fever: History, epidemiology, pathogenesis, clinical syndrome and genetic diversity" (2013 b s t r a c tCrimean-Congo hemorrhagic fever (CCHF) is the most important tick-borne viral disease of humans, causing sporadic cases or outbreaks of severe illness across a huge geographic area, from western China to the Middle East and southeastern Europe and throughout most of Africa. CCHFV is maintained in vertical and horizontal transmission cycles involving ixodid ticks and a variety of wild and domestic vertebrates, which do not show signs of illness. The virus circulates in a number of tick genera, but Hyalomma ticks are the principal source of human infection, probably because both immature and adult forms actively seek hosts for the blood meals required at each stage of maturation. CCHF occurs most frequently among agricultural workers following the bite of an infected tick, and to a lesser extent among slaughterhouse workers exposed to the blood and tissues of infected livestock and medical personnel through contact with the body fluids of infected patients. CCHFV is the most genetically diverse of the arboviruses, with nucleotide sequence differences among isolates ranging from 20% for the viral S segment to 31% for the M segment. Viruses with diverse sequences can be found within the same geographic area, while closely related viruses have been isolated in far distant regions, suggesting that widespread dispersion of CCHFV has occurred at times in the past, possibly by ticks carried on migratory birds or through the international livestock trade. Reassortment among genome segments during co-infection of ticks or vertebrates appears to have played an important role in generating diversity, and represents a potential future source of novel viruses. In this article, we first review current knowledge of CCHFV, summarizing its molecular biology, maintenance and transmission, epidemiology and geographic range. We also include an extensive discussion of CCHFV genetic diversity, including maps of the range of the virus with superimposed phylogenetic trees. We then review the features of CCHF, including the clinical syndrome, diagnosis, treatment, pathogenesis, vaccine development and laboratory animal models of CCHF. The paper ends with a discussion of the possible future geographic range of the virus. For the benefit of researchers, we include a Supplementary Table listing all published reports of CCHF cases and outbreaks in the English-language literature, plus some principal articles in other languages, with total case numbers, case fatality rates and all CCHFV strains on GenBank.

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Section: Genetic Driftmentioning

confidence: 75%

Crimean-Congo hemorrhagic fever: History, epidemiology, pathogenesis, clinical syndrome and genetic diversity

et al. 2013

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“…Dolaşımdaki AHFV suşları arasın-daki rekombinasyona bağlı olarak, nükleotid sayılarında kü-çük farklılıklar gözlenebilmektedir (17 (23). Ancak suşun referans suşla da özdeş olması, sonradan bir laboratuvar kontaminasyonu olarak yorumlanmıştır (24).…”

Section: Etyolojiunclassified

“…İki virus arasındaki farklılaş-manın geçmişinin, önceleri 66-177 yıl olduğu, hatta 1942 yılı gibi yakın bir tarihe uzandığı hesaplanmışken (24,27); insan olgularının yanı sıra kenelerden izole edilen 16 AHFV suşu-nun ve arşivde tutulan üç KFDV suşunun tam genom dizileri çıkarılarak yapılan son filogenetik analizin bulguları, farklı-laşmanın 700 yıl (121-1487 yıl) kadar gerilere gidebileceğini göstermektedir. Bu bulgular, KFDV'nin, endemik olduğu böl-geden yaklaşık 4000 km uzakta olan Suudi Arabistan'a, çok yakın bir tarihte girmiş olamayacağını düşündürmektedir.…”

Section: Etyolojiunclassified

Al-Khurma Haemorrhagic Fever

Eraksoy¹

2015

Klimik Dergisi

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ÖzetEl-Hurma kanamalı ateşi (AHF) ilkin Suudi Arabistan'da tanım-lanmış ve Hac ve Umre için bu ülkeye gelenlerde dikkate alın-ması gereken sağlık riskleri arasında sayılan yeni bir infeksiyon hastalığıdır. Tanısı konulmuş ilk olgu, Taif yakınlarında küçük bir yerleşim yeri olan el-Hurma'dan gelen bir koyunu kestikten sonra hastalanan bir kasaptır. El-Hurma kanamalı ateşi virusu (AHFV), Flaviviridae ailesinin Flavivirus cinsindeki, konaklarını memelilerin oluşturduğu keneyle bulaşan virus alt grubu üyesi olan Kyasanur Ormanı hastalığı virusunun bir varyantıdır. Suudi Arabistan'ın batısında ve güneyindeki erişkin yumuşak ve sert kenelerden izole edilmiştir. Koyun, keçi ve develerle temas etmenin ve çiğ deve sütü içmenin klinik hastalıkla bağlantısı vardır. Suudi Arabistan'daki seroprevalansının %1 olduğu anlaşılmaktadır. AHFV infeksiyonunun Mısır'ın güneydoğusunda Sudan sınırına giden turistlerde de saptanmasıyla coğrafi yayılımının daha geniş olduğu anlaşılmıştır. Kuluçka süresi kene temasından sonra 2-4 gündür. Hastaların çoğu, özgül olmayan ve benzer ateşli hastalıklardan ayırt edilmesi güç bir klinik tabloyla başvurur. Diğer viral kanamalı ateşlerde de görülebilen gastrointestinal, hepatik ve nörolojik tutulumla birlikte kanama belirti ve bulguları, ağır formlardaki başlıca klinik özelliklerdir. Hastaneye yatırılmış hastalardaki en önemli laboratuvar bulguları, karaciğer enzimleri, kreatin kinaz ve laktat dehidrogenaz düzeylerinde yükselmeler, trombositopeni ve lökopenidir. Hızlı laboratuvar tanısı, çoğunlukla viremik dönemde plazma ve serumdaki viral RNA'yı belirleyen "real time" RT-PCR'a dayanır. Biyogüvenlik düzeyi 3 ya da 4 olan bir ajan olmasından dolayı, virusun hücre kültüründe ya da henüz sütten kesilmemiş farelerde izolasyonu, rutin olarak yapılmaz. Yakın viruslar arasındaki antijenik çapraz reaksiyonlar, serolojik testleri yorumlarken dikkatli olmayı gerektirir. Son gözlemler, genel olarak olgu fatalite hızının, çok daha yüksek olan ilk verilerin tersine, %1-2 olduğu-nu göstermiştir. İnsandan insana bulaşma bildirilmemişse de, sağlık çalışanlarının, standard önlemleri almaları uygun olur. AbstractAl-Khurma haemorrhagic fever (AHF) is an emerging infectious disease described initially in Saudi Arabia and considered among major health risks to the pilgrims during Hajj and Umrah. The first case was diagnosed in a butcher who became sick after he slaughtered a sheep originated from al-Khurma, a small settlement near Taif. The causative agent, al-Khurma haemorrhagic fever virus (AHFV), is a variant of Kyasanur Forest disease virus, a member of the mammalian tick-borne virus subgroup of the genus Flavivirus, family Flaviviridae. It has been isolated from adult soft and hard ticks collected in both western and southern Saudi Arabia. Clinical cases have been linked to handling sheep, goats and camels and to drinking raw camel milk. Seroprevalence in Saudi Arabia seems as 1%. Confirmation of AHFV infection in tourists visiting southeastern Egypt near the Sudanese border extended its geographical spread. Incu...

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“…Since 1955, the disease has been known in the Southwest of India. After comparing 48 KFDV isolates, it was concluded that the isolates from India, Saudi Arabia (Alkhurma virus) and China shared their last common ancestor around 1942 (Mehla et al, 2009). However, it should be added that the authors questioned the authenticity of the Chinese isolate due to its complete identity with the Indian reference strain isolated in 1957.…”

Section: Kyasanur Forest Diseasementioning

confidence: 99%

“…The reason for this is the low viremia. In addition, it is considered possible that cattle play a role as amplification host (Mehla et al, 2009). The ratio of clinical and subclinical infections of >50 % is high (Pandit, 1960).…”

Section: Kyasanur Forest Diseasementioning

confidence: 99%