zeller 4/2/09 11:52 am Page 72
Viral Infections
2001.
38,39
The virus produced high mortality mainly in blackbirds (Turdus viruses are also present in Iraq, Iran, Pakistan, Afghanistan and India. They
merula) until herd immunity was established. USUV was also detected in caused a considerable problem among troops operating in the endemic
neighbouring Hungary.
40
Inkoo virus (INKV), a member of the Bunyavirus areas during World Wars One and Two. The incidence of these two viruses
California serogroup, has been reported in northern Europe (Finland, remains high in most of their endemic areas. In a survey conducted in the
Norway, Sweden and Estonia) and the Russian Federation.
41
INKV is Adriatic littoral of Croatia, 23% of those examined were found positive for
transmitted via Ae. communis and Ae. punctor, which feed on large Naples virus.
63
Other surveys revealed high antibody prevalence rates for
mammals such as cows, reindeers and moose.
36
Common in Sweden, the Naples and Sicilian viruses, illustrating that sandfly fevers pose a significant
antibody prevalence in humans increases northwards up to 69% in public health problem.
64
The importation of sandfly fevers by tourists and
Finland.
41
Recent studies showed an antibody prevalence of about 50% in soldiers returning from endemic areas is also considered a growing
febrile patients in Finland
42,43
without evidence of human disease. In Russia, problem.
65
Toscana virus was isolated from Phlebotomus perniciosus in
patients with antibodies to INKV had chronic neurological disease.
44,45
Tuscany, Italy in 1971.
62
It has been associated with acute neurological
Tahyna virus (TAHV) is also a member of the Bunyavirus California complex. disease. Clinical cases of aseptic meningitis or meningoencephalitis caused
It was isolated from a pool of Ae. caspius in 1958 in Slovakia.
46
The virus by the toscana virus are observed in central Italy during the summer.
appears to be present in most countries of Europe in areas where its main Nicoletti and co-workers concluded that toscana virus is the most common
vectors (Ae. vexans, Ae. caspius, Ae cinereus) are abundant. In human viral agent involved in acute infections of the central nervous system (CNS)
patients, the virus may present with influenza-like symptoms, but in children in central Italy. The most common vector in Italy is Ph.
meningoencephaltis and atypical pneumonia have also been observed.
44,47
perniciosus. Sandfly fever viruses may be the cause of hundreds of
The virus is transmitted transovarially in Ae. vexans and C. annulata thousands of infections per year in southern Europe.
66
As only some of these
mosquitoes, and small mammals such as hares, rabbits and hedgehogs serve human cases show clinical illness, the infection is probably under-diagnosed,
as amplification hosts.
48
Batai virus (Bunyavirus complex) was first isolated in especially in returning tourists.
62,67
Europe in Slovakia from An. maculipennis in 1960
49
and has been reported
in several countries from Asia and Africa. It has been isolated in Norway, Tick-borne Viruses
Sweden, Finland, the Russian Federation, the Czech Republic, Slovakia, Tick-borne encephalitis virus (TBEV) is the most important and
Austria, Hungary, Portugal and Romania.
50
The vectors appear to be mainly widespread arbovirus transmitted by ticks in Europe. It is a member of the
An. maculipennis and An. claviger, although the virus has been isolated Flaviviridae family and encompasses three diseases; ‘louping illness’,
from Ae. communis and several other Aedes and Culex species. Batai virus central European tick-borne encephalitis (TBE) and Russian spring–
is not associated with human diseases in Western Europe, and its potential summer encephalitis (RSSE).
68
These three diseases differ mainly in
for inducing human disease is considered low.
50
severity:
68
louping illness is the mildest and RSSE seems the most severe.
Humans are infected by the bite of infected ticks or by the ingestion of
Dengue fever (Flavivirus complex) was once endemic in southern Europe in raw milk from infected domestic animals.
69
those regions where the vector, Ae. aegypti, was present. In 1927 to 1928
a massive dengue epidemic, with high mortality, occurred in Athens, TBEV is often the cause of a serious acute CNS disease, which may result
Greece.
51
Today, dengue is the most important arboviral human disease in death or long-term neurological sequelae. About 40% of infected
globally, but the disease is no longer present in Europe. Piped water patients are left with a residual post-encephalitic syndrome. The mortality
distribution has led to the disappearance of Ae. aegypti in Europe for many of the central European form of TBE is 0.7–2%.
68
The mortality rate for
years. The cold-resistant Ae. albopictus, however, is also a vector of dengue RSSE, on the other hand, can be as high as 25%. Although no specific
in some parts of the world, and the species is progressively spreading in treatment is available, an effective vaccine exists and its use is
Europe. Travellers returning from dengue-endemic countries, and a viraemic recommended for persons at risk, such as forest workers and people
traveller bitten by Ae. albopictus, could well be the source of renewed visiting an endemic region. The virus is endemic in most of western
dengue transmission in Europe.
52,53
ChikungunyaI (Togaviridae, Alphavirus) Europe, with foci in the Alsace region of France, Germany, Austria, the
was reported in sub-Saharan Africa, India and South East Asia with recurrent Balkans and Scandinavia and across the Russian Federation to the Pacific
outbreaks with numerous cases. The well-known vector is Ae. aegypti. Ae. Ocean.
70,71
The tick is both vector and reservoir of the virus and remains
albopictus was recently recognised as the main vector in the Indian Ocean infected in all its stages and throughout its life.
72
There are indications of
islands.
54
The mosquito has spread to many countries, reaching Europe in an increasing trend in the incidence of the disease, and there appears to
1989 and Italy in 1990.
55,56
At least one-third of the US is infested with the be shift in geographical distribution. Infection rates in ticks can be very
species.
57
In August 2007, an outbreak occurred in Emilia-Romagna, Italy, a high, up to 50%, in TBE-endemic high-risk areas.
70,73
region heavily infested by Ae. albopictus.
58,59
It originated from a traveller
from India who was visiting relatives
60
and resulted in more than 200 cases Crimean Congo haemorrhagic fever virus (CCHFV) is caused by a
being recorded. The emergence of this type of viral zoonosis was predicted Nairovirus. All the members of the Nairovirus genus are transmitted by
and may serve as a warning for the possible spread of viruses such as argasid or ixodid ticks, but only three of them cause disease in humans: the
dengue, Rift Valley fever and others currently unknown in Europe.
61
‘Dugbe’ and ‘Nairobi’ sheep viruses, and CCHFV, which is the most
important human pathogen in this group. Russian scientists first observed
Sandfly-borne Viruses CCHF in 1944–1945 in the Crimea.
74
Congo virus was first isolated in Africa
The Naples and Sicilian viruses are largely responsible for the sandfly-borne from the blood of a febrile patient in Zaire in 1956 and was later shown to
diseases also known as pappataci or sandfly fever. Sabin isolated both be identical to the virus detected in the Crimea.
74
In Europe, CCHF has been
viruses during World War Two.
62
Naples and Sicilian virus circulate reported in Albania, Bulgaria, Greece, Hungary, Kosovo, the former
throughout southern Europe, the Balkan region and the eastern Yugoslav Republic of Macedonia (FYROM), Portugal, Romania, Russia,
Mediterranean basin, including Cyprus, and along the Black Sea coast. The Turkey and Ukraine by the occurrence of human cases, by isolations from
72 EUROPEAN INFECTIOUS DISEASE
Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92  |  Page 93  |  Page 94  |  Page 95  |  Page 96  |  Page 97  |  Page 98  |  Page 99  |  Page 100  |  Page 101  |  Page 102  |  Page 103  |  Page 104  |  Page 105  |  Page 106  |  Page 107  |  Page 108  |  Page 109  |  Page 110  |  Page 111  |  Page 112  |  Page 113  |  Page 114  |  Page 115  |  Page 116