Recent Findings
1. Unusual
presentation of life-threatening Toscana virus meningoencephalitis.
(Baldelli F, Ciufolini MG, Francisci D, Marchi A, Venturi
G, Fiorentini C, Luchetta ML, Bruto L, Pauluzzi S. Clinical
Infectious Diseases;38:515-520. 2004)
Recently, two cases of an atypical clinical presentation of Tuscana Virus
infection were identified. Tuscana Virus is a member of the genus Phlebovirus
(Sandfly fever group) along with Sicilian and Naples viruses. It is neurotropic
and normally causes asceptic meningitis or mild meningoencephalitis that lasts
for 7-10 days. Two recent cases, a 19 year old girl and her 16 year old brother,
presented with atypical symptoms because the infection lead to life-threatening
meningoencephalitis. The disease symptoms were characterized by stiff neck,
deep coma, maculopapular rash, diffuse lymphadenopathy, hepatosplenomegaly,
renal involvement, tendency to bleed, testicular involvement, and diffuse
intravascular coagulation. Neurologial sequela were also present in the patients.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=14765344&dopt=Abstract
2. Bovine
aortic endothelial cells are susceptible to hantavirus infection; a new aspect
in hantavirus ecology. (Muranyi
W, Kehm R, Bahr U, Muller S, Handermann M, Darai G, Zeier M. Virology. 2004
Jan 5;318(1):112-22.)
A recent study showed that bovine aortic endothelial
cells could be infected by a hantavirus (Puumula virus). Twelve weeks after
initial infection, Puumula nucleocapsid protein was found in 95% of aortic
cells infected with the virus. A previous study by Danes et al. showed that
2% of examined cattle had antibodies to hantavirus. This study was executed
to clarify the relationship. The results raise new questions on hantavirus
host range, species specificity, reservoirs, transmission, and ecology.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=14972540&dopt=Abstract
3. Bunyamwera bunyavirus RNA synthesis
requires cooperation of 3'- and 5'-terminal sequences. (Barr
JN, Wertz GW. Journal of Virology, February 2004, p. 1129-1138, Vol. 78, No.
3)
The Bunyamwera virus genome, like all
negative sense RNA virus genomes, exhibits nucleotide complementarity between
the 3' and 5' ends of its terminal non-translating regions. For Bunyamwera,
this pattern is present in all three segments of the genome. This study saught
to determine whether this complementarity in all three segments was the result
of a functional requirement for RNA synthesis, or whether it was due to genomic
and anti-genomic non-translating regions having similar functions requiring
sequence conservation. The results indicated that cooperation between the
3' and 5' non-translating regions through base pairing interactions was a
requirement for RNA synthesis.
4. Genetic
similarity of Puumala viruses found in Finland and western Siberia and of
the mitochondrial DNA of their rodent hosts suggests a common evolutionary
origin. (Dekonenko
A, Yakimenko V, Ivanov A, Morozov V, Nikitin P, Khasanova S, Dzagurova T,
Tkachenko E, Schmaljohn C.
Infection, Genetics and Evolution Volume 3, Issue 4 , November 2003, Pages
245-257)
This study showed that 18/678 small
mammals (all 18 were of the Clethrionomys species) trapped in Siberia
were antigen positive for Puumula virus. The viral strain was similar to hantavirus
strains isolated from Clethrionomys glareolus rodents from Finland.
These findings suggest that Puumula viruses as well as their rodent hosts
share a common evolutionary origin.
5. Induction
of severe disease in hamsters by two sandfly fever group viruses, Punta toro
and Gabek Forest (Phlebovirus, Bunyaviridae), similar to that caused by Rift
Valley fever virus. (Fisher AF, Tesh RB, Tonry J, Guzman H,
Liu D, Xiao SY. American Journal of Tropical Medicine and Hygiene, 69(3),
2003, pp. 269-276.)
Adult golden hamsters were inoculated with two Sandfly fever
group viruses, Punta Toro and Gabek Forest. They subsequently developed a
fulminanting illness characterized by hepatic and splenic necrosis and interstitial
pneumonitis. The illness was fatal. Necropsy and histopathological examination
showed changes in multiple organs similar to those found in Rift Valley Fever.
This study thus demonstrated that the hamster-phlebovirus model could be used
as an alternative animal model for Rift Valley Fever.