impaginato piccolo - Società Italiana di Parassitologia (SoIPa)

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(Krause et al., 1995). In Italy, there is only limited
information on the prevalence of cryptosporidiosis
(Giangaspero et al., 2007). In children, it has been
reported to range from 1.9% to 7.2% across the country
(Caprioli et al., 1989; Brandonisio et al., 1996).
Since the introduction of HAART in 1995, the prevalence
among HIV-positive people has decreased dramatically
(Pozio and Gomez-Morales, 2005). In the
Netherlands, case-control studies have reported a
prevalence of 2.2 % among persons with gastroenteritis,
whereas the prevalence was only 0.3% in controls
(Mank et al., 1997, de Wit et al., 2001). In this country,
there was a seasonal peak in the late summer. In
Spain, according to the Microbiological Information
System, which reports cases on a voluntary basis and
covers about 25% of the Spanish population, from
1995 to 2002 there were 823 cases of cryptosporidiosis,
with a yearly average of 103 cases.
With regard to Cryptosporidium infection in livestock
in Denmark, the herd prevalence has been reported to
be age-specific; it is 16% among sows, 31% among
piglets, and 100% among weaners; in cattle, it is 14%
among cows, 96% among young calves, and 84% for
older calves (Maddox-Hytell, et al., 2006). In France,
the prevalence has been reported to be 43.4% among
calves (Lefay et al., 2000); in goats, it is 16-58%
among very young animals, decreasing to 2.5% in older
animals (Castro-Harmida et al., 2005). In Germany, a
prevalence as high as 50% has been reported in young
calves and lambs with diarrhoea. In five German state
veterinary laboratories, Cryptosporidium infection was
diagnosed yearly in 19-36% of bovine faecal samples
(Joachim et al., 2003); in pigs, horses, dogs and cats, the
reported prevalence is 1-2% (Epe et al., 2004). In Italy,
a high prevalence (up to 75%) has been detected in
young calves, kids, and lambs, yet only on farms with a
low level of hygiene such as the backyard livestock,
whereas this parasite is practically non-existent on modern
industrialised farms (Giangaspero et al., 2007). In
the Netherlands, a one-year study performed at a dairy
farm reported a prevalence of up to 39% in calves that
were 1-3 weeks old; seasonal variation was also
observed, with the lowest prevalence in June (2.4%)
and the highest prevalence in December (22%)
(Huetink et al., 2001). Moreover, in the Netherlands,
studies in veal calves showed high prevalences on herd
bases from 99% herd prevalence at a age of 1-6 weeks
to 70% at an age of 35 weeks (Medema and Schijven,
2001). In Spain, C. parvum oocysts were identified in
59% of lambs aged from 1 day to 3 months and in 7.8%
of ewes older than 1 year. In pigs, the prevalence was
significantly higher in weaned 1-2-month-old piglets
(59.2%) than in fattening 2-6-month-old pigs (34.3%)
(Quilez et al., 1996). A prevalence of 7.4% was found
in dogs (Causape et al., 1996). In Sweden, C. parvum
was the second most common pathogen in diarrhoeic
calves younger than 3 months (Björkman et al., 2003).
Sarcocystis spp.
Sarcocystis spp. are very common in domestic animals,
and although two species are zoonotic (i.e., Sarcocystis
E. Pozio - Foodborne parasitic zoonoses
hominis, related to cattle, and Sarcocystis suishominis,
related to pigs), the knowledge on the prevalence of
these two protozoa in humans is very limited. Fewer
than 10 cases of muscular sarcocystosis have been documented
in Europe and fewer than 100 cases have been
reported worldwide. Intestinal sarcocystosis was documented
in 10.4% and 7.3% of faecal samples of
asymptomatic children in Poland and Germany, respectively.
In Germany, S. hominis has been detected in up
to 63% of cattle, yet the identification of the parasite at
the species level is questionable. In Germany and
Austria, the prevalence of S. suihominis in pigs is lower
than that of S. hominis in cattle (Fayer, 2004).
Toxoplasma gondii
This zoonotic parasite is widespread in humans, though
its prevalence greatly varies by country. In the UK, it is
estimated that 16-40% of the general population is
infected, whereas in continental Europe the estimates
range from 50 to 80% (Dubey and Beattie, 1988). In
some European countries (e.g., France and Austria),
testing for T. gondii infection is compulsory for all pregnant
women, whereas in many other countries the costbenefit
ratio of such mass screening is currently being
debated (Remington et al., 1995). Because the epidemiological
studies on the prevalence of T. gondii antibodies
in humans have been carried out using different tests,
among different groups, and at different times, it is very
difficult to compare the results. In Italy, in the 1980s, the
sero-prevalence was 17.9% for paediatric ages, whereas
it was as high as 48.5% in the general adult population.
In pregnant women, the seroprevalence ranges from
10.9% in Norway to 67.4% in France, with a prevalence
of 21.1% in Sweden, 25.7% in Spain, 40.0% in Italy,
and 50.0% in Belgium (Hall, et al., 2001).
In livestock, the prevalence greatly varies depending on
the animal species, age, and type of breeding, with the
highest prevalence in sheep and goats, in which the
parasite can cause embryonic death and resorption,
foetal death and mummification, abortion, stillbirth,
and neonatal death. The disease is more severe in goats
than in sheep. Outbreaks of toxoplasmosis have been
reported in pigs with mortality in piglets. In Poland, the
seroprevalence has been found to be high in cattle
(53.8%) and pigs (15%) (Sroka, 2001). In the
Netherlands, the seroprevalence was very low in finishing
pigs (1.8%) and in fattening calves (1.2%), whereas
it was 30.9% among sows and 27.9% among dairy
cattle (van Knapen et al., 1995). In Denmark, the seroprevalence
was 0.5% in fattening pigs bred indoors,
whereas it was higher among sows (29%) because they
have outdoor access. In Portugal, the seroprevalence
was 15.6% in fattening pigs with outdoor access and
27.1% in free-range poultry. In Greece, the seroprevalence
in cattle and sheep grazing in the same pasture
was 39.7% and 26.2%, respectively (www.iss.it/crlp/).
Diphyllobotrium latum
There are three types of epidemiological situations in
Europe: countries where human infection has been
documented relatively frequently; countries where spo-