Papers by Giovanni Cattoli
Journal of Virology, 2010
of HPAI H5N1 viruses into Nigeria, although virus spread through the movement of poultry and poul... more of HPAI H5N1 viruses into Nigeria, although virus spread through the movement of poultry and poultry products cannot be excluded. Our study provides new insight into the genesis and evolution of H5N1 influenza viruses in Nigeria and has important implications for targeting surveillance efforts to rapidly identify the spread of the virus into and within Nigeria.
Emerging Infectious Diseases, 2015
The clinical, virological and pathological findings observed in a natural outbreak of highly path... more The clinical, virological and pathological findings observed in a natural outbreak of highly pathogenic avian influenza in intensively farmed ostriches (Struthio camelus) are reported. Clinical signs characterized by anorexia, depression, nervous and enteric signs were observed in young birds, which resulted in death of 30% of the affected birds. Virus isolation performed in accordance with the guidelines listed in European Union Directive 92/40/EEC yielded an influenza A virus of the H7N1 subtype with a deduced cleavage site motif containing multiple basic amino acids, typical of highly pathogenic viruses. Gross lesions, mainly haemorrhagic enteritis and liver degeneration and necrosis, were confirmed by histopathology and immunohistochemistry, resulting in the detection of necrotic lesions and influenza A nucleoprotein in selected organs. The findings reported indicate that ostriches are susceptible to highly pathogenic avian influenza.
Infection, Genetics and Evolution, 2015
Influenza A virus can quickly acquire genetic mutations that may be associated with increased vir... more Influenza A virus can quickly acquire genetic mutations that may be associated with increased virulence, host switching or antigenic changes. To provide new insights into the evolutionary dynamics and the adaptive strategies of distinct avian influenza lineages in response to environmental and host factors, we compared two distinct avian influenza epidemics caused by the H7N1 and H7N3 subtypes that circulated under similar epidemiological conditions, including the same domestic species reared in the same densely populated poultry area for similar periods of time. The two strains appear to have experienced largely divergent evolution: the H7N1 viruses evolved into a highly pathogenic form, while the H7N3 did not. However, a more detailed molecular and evolutionary analysis revealed several common features: (i) the independent acquisition of 32 identical mutations throughout the entire genome; (ii) the evolution and persistence of two sole genetic groups with similar genetic characteristics; (iii) a comparable pattern of amino acid variability of the HA proteins during the low pathogenic epidemics; and (iv) similar rates of nucleotide substitutions. These findings suggest that the evolutionary trajectories of viruses with the same virulence level circulating in analogous epidemiological conditions may be similar. In addition, our deep sequencing analysis of 15 samples revealed that 17 of the 32 parallel mutations were already present at the beginning of the two epidemics, suggesting that fixation of these mutations may occur with different mechanisms, which may depend on the fitness gain provided by each mutation. This highlighted the difficulties in predicting the acquisition of mutations that can be correlated to viral adaptation to specific epidemiological conditions or to changes in virus virulence.
Avian Diseases, 2003
From 1997 to 2001, Italy has been affected by two epidemics of high-pathogenicity avian influenza... more From 1997 to 2001, Italy has been affected by two epidemics of high-pathogenicity avian influenza. The first epidemic was caused by a virus of the H5N2 subtype and was limited to eight premises in backyard and semi-intensive flocks. The prompt identification of the disease was followed by the implementation of European Union (EU) directive 92/40/EEC and resulted in the eradication of infection without serious consequences to the poultry industry. The 1999-00 epidemic was caused by a virus of the H7N1 subtype that originated from the mutation of a low pathogenic virus and resulted instead in a devastating epidemic that affected industrially reared poultry, culminating in the infection of 413 flocks. The description of the epidemics and the result of the control policies are reported.
Journal of virology, 2014
Avian H7 influenza viruses are recognized as potential pandemic viruses, as personnel often becom... more Avian H7 influenza viruses are recognized as potential pandemic viruses, as personnel often become infected during poultry outbreaks. H7 infections in humans typically cause mild conjunctivitis; however, the H7N9 outbreak in the spring of 2013 has resulted in severe respiratory disease. To date, no H7 viruses have acquired the ability for sustained transmission among humans. Airborne transmission is considered a requirement for the emergence of pandemic influenza, and advanced knowledge of the molecular changes or signature required for transmission would allow early identification of pandemic vaccine seed stocks, screening and stockpiling of antiviral compounds, and eradication efforts focused on flocks harboring threatening viruses. Thus, we sought to determine if a highly pathogenic influenza A H7N1 (A/H7N1) virus with no history of human infection could become capable of airborne transmission among ferrets. We show that after 10 serial passages, A/H7N1 developed the ability to b...
Journal of immunology research, 2014
The increased number of outbreaks of H5 and H7 LPAI and HPAI viruses in poultry has major public ... more The increased number of outbreaks of H5 and H7 LPAI and HPAI viruses in poultry has major public and animal health implications. The continuous rapid evolution of these subtypes and the emergence of new variants influence the ability to undertake effective surveillance. Retroviral pseudotypes bearing influenza haemagglutinin (HA) and neuraminidase (NA) envelope glycoproteins represent a flexible platform for sensitive, readily standardized influenza serological assays. We describe a multiplex assay for the study of neutralizing antibodies that are directed against both influenza H5 and H7 HA. This assay permits the measurement of neutralizing antibody responses against two antigenically distinct HAs in the same serum/plasma sample thus increasing the amount and quality of serological data that can be acquired from valuable sera. Sera obtained from chickens vaccinated with a monovalent H5N2 vaccine, chickens vaccinated with a bivalent H7N1/H5N9 vaccine, or turkeys naturally infected ...
Veterinary Record, 2004
... Veterinary Pathology 25, 529-530 HONG, CB, DONAHUE, JM, GILES, RC, PETRITES-MURPHY, MB, POONA... more ... Veterinary Pathology 25, 529-530 HONG, CB, DONAHUE, JM, GILES, RC, PETRITES-MURPHY, MB, POONACHA, K. B.,ROBERTS, A. W., SMITH, B. J., TRAMONTIN, R. R., TUTTLE, PA & SWERCZEK, T.W. (1994) Equine abortion and stillbirthin central Kentucky during 1988 ...
PloS one, 2008
H9N2 avian influenza A viruses are endemic in poultry of many Eurasian countries and have caused ... more H9N2 avian influenza A viruses are endemic in poultry of many Eurasian countries and have caused repeated human infections in Asia since 1998. To evaluate the potential threat of H9N2 viruses to humans, we investigated the replication and transmission efficiency of H9N2 viruses in the ferret model. Five wild-type (WT) H9N2 viruses, isolated from different avian species from 1988 through 2003, were tested in vivo and found to replicate in ferrets. However these viruses achieved mild peak viral titers in nasal washes when compared to those observed with a human H3N2 virus. Two of these H9N2 viruses transmitted to direct contact ferrets, however no aerosol transmission was detected in the virus displaying the most efficient direct contact transmission. A leucine (Leu) residue at amino acid position 226 in the hemagglutinin (HA) receptor-binding site (RBS), responsible for human virus-like receptor specificity, was found to be important for the transmission of the H9N2 viruses in ferret...
Viruses, 2009
Since its emergence in South East Asia in 2003, Highly Pathogenic Avian Influenza (HPAI) A/H5N1 h... more Since its emergence in South East Asia in 2003, Highly Pathogenic Avian Influenza (HPAI) A/H5N1 has reportedly caused outbreaks in poultry and/or wild birds in 62 countries, of which 24 were in Europe. Interestingly, out of the many genetic clades circulating in Asia, the westward spread of HPAI A/H5N1 to Central Asia, the Middle East, Europe and Africa was dominated by one single clade, namely clade 2.2. In this paper, we review and update through phylogenetic and gene migrational analysis the information concerning the evolution and the molecular epidemiology of HPAI A/H5N1 on the European continent.
Veterinary Microbiology, 2011
The use of diagnostic methods based on molecular technology has improved substantially over the l... more The use of diagnostic methods based on molecular technology has improved substantially over the last decade; consequently, laboratory tests for the identification and characterisation of avian influenza (AI) viruses have become available. Such tests may be used to detect the AI viral genome directly from clinical specimens as well as to generate data on the molecular characteristics of an isolate or of viral RNA present in a sample collected from an infected animal. In addition, the current definitions of highly pathogenic AI (HPAI) (EC 2006; OIE 2004) are based on the results of conventional and molecular techniques, thus, the latter are among the official methods used to identify virulence factors and to confirm the presence of HPAI viruses in laboratory specimens.
Virus Research, 2006
In order to support eradication efforts of avian influenza (AI) infections in poultry, the implem... more In order to support eradication efforts of avian influenza (AI) infections in poultry, the implementation of "DIVA" vaccination strategies, enabling the Differentiation of Infected from Vaccinated Animals have been recommended by international organisations. A system, based on the detection of antibodies to the Non-Structural 1 (NS1) protein of AI has been proposed but the success of such a system lies in the conservation of the NS1 protein among different AI isolates. With this in mind, the ns1 gene of 40 influenza A viruses isolated from a spectrum of avian species was sequenced and compared phylogenetically. The isolates included both low pathogenicity (LPAI) (n = 22) and highly pathogenic (HPAI) (n = 18) viruses of the H7 subtype and were representative of the avian influenza viruses that circulated in Northern Italy from 1999 to 2003. Size variation in the predicted amino acid sequence of each NS1 was revealed with two different levels of carboxy-terminal truncation being observed. Of the 40 isolates analysed, 16 had a full-length NS1 protein of 230 aa, 6 had a truncated protein of 220 aa and 18 had an intermediate truncation resulting in a protein of 224 aa. All of the H7N1 HPAI isolates possessed the intermediate carboxy-terminal truncation. In addition, all of the H7N1 LPAI viruses circulating at the beginning of the epidemic had a full length NS1 while those circulating towards the end of the period had a truncated protein.
Virus Genes, 2010
The haemagglutinin-neuraminidase (HN) and fusion protein (F) gene of four avian paramyoviruses se... more The haemagglutinin-neuraminidase (HN) and fusion protein (F) gene of four avian paramyoviruses serotype 9 (APMV9) recently isolated from wild birds in Italy have been sequenced. A comparison between the sequences of these four isolates and the prototype virus PMV-9/domestic Duck/New York/22/78 revealed significant sequence variation that suggests that different lineages exist among APMV-9 viruses similar to that seen for APMV-1 (Newcastle disease).
Virology Journal, 2010
Background: Virological, molecular and serological studies were carried out to determine the stat... more Background: Virological, molecular and serological studies were carried out to determine the status of infections with avian influenza viruses (AIV) in different species of wild waterbirds in Iran during [2003][2004][2005][2006][2007]. Samples were collected from 1146 birds representing 45 different species with the majority of samples originating from ducks, coots and shorebirds. Samples originated from 6 different provinces representative for the 15 most important wintering sites of migratory waterbirds in Iran.
Virology, 2007
An experimental infection of mice was performed in order to investigate the potential for intersp... more An experimental infection of mice was performed in order to investigate the potential for interspecies transmission in mammals of Italian HPAI viruses of the H7N1 subtype. Three avian origin isolates were selected, two strains obtained from ostrich (one of which contained a PB2-627 Lysine residue) and one from a chicken. Following intranasal infection of mice, clinical signs and mortality were recorded in the experimental groups challenged with the two ostrich isolates, while only weight loss was observed in those receiving the chicken strain. Viruses were recovered to a varying extent from respiratory and nervous tissues of infected animals. These results suggest that HPAI viruses, other than H5N1 and H7N7, may have zoonotic implications, and support the consensus that AI infections in poultry are to be eradicated rather than contained.
Veterinary Research, 2010
Highly pathogenic avian influenza (HPAI) viruses of the H5 and H7 subtype pose a major public hea... more Highly pathogenic avian influenza (HPAI) viruses of the H5 and H7 subtype pose a major public health threat due to their capacity to cross the species barrier and infect mammals, for example dogs, cats and humans. In the present study we tested the capacity of selected H7 and H5 HPAI viruses to infect and to be transmitted from infected BALB/c mice to contact sentinels. Previous experiments have shown that viruses belonging to both H5 and H7 subtypes replicate in the respiratory tract and central nervous system of experimentally infected mice. In this study we show that selected H7N1 and H5N1 HPAI viruses can be transmitted from mouse-to-mouse by direct contact, and that in experimentally infected animals they exhibit a different pattern of replication and transmission. Our results can be considered as a starting point for transmission experiments involving other influenza A viruses with a 2-3 receptor affinity in order to better understand the viral factors influencing transmissibility of these viruses in selected mammalian species.
Veterinary Microbiology, 1999
Helicobacter-like organisms are frequently observed in the stomach of dogs but the relationship b... more Helicobacter-like organisms are frequently observed in the stomach of dogs but the relationship between these microorganisms and gastric pathology has not been clearly established. Different species of helicobacters are known to be present in the canine stomach but their specific prevalence in naturally infected dogs is unknown. The aims of this study were to isolate and characterize helicobacters in canine gastric biopsies, to compare the commonly used tests for the identification of Helicobacter spp. and to determine the occurrence of these species in dogs. Twenty-three out of 25 dogs (92%) were positive for Helicobacter-like organisms in cytological screening. Culture was successful from biopsies of 5/25 dogs. The isolates were analyzed by electron microscopy, biochemical and physiological tests, whole protein analysis and 16S rDNA sequencing. Helicobacter felis was identified in four samples and Helicobacter bizzozeronii in one sample. Only the whole protein analysis in combination with electron microscopy was able to clearly discriminate the two species. Compared to the high prevalence of Helicobacter-like organisms, the occurrence of H. felis and H. bizzozeronii, was low (17 and 4%, respectively). No Flexispira rappini-like organisms or H. salomonis were detected. Electron microscopy revealed that H. bizzozeronii-like microorganisms were present in three additional biopsies where we were unable to culture any Helicobacter-like organisms. These observations indicate that in the stomach of dogs not all helicobacters are culturable. The unculturable bacteria appeared to be the prevalent ones and may represent different spiral organisms. The presence of distinct helicobacters with different Veterinary Microbiology 70 (1999) 239±250 (J.G. Kusters) 0378-1135/99/$ ± see front matter # 1999 Elsevier Science B.V. All rights reserved. PII: S 0 3 7 8 -1 1 3 5 ( 9 9 ) 0 0 1 5 0 -9 characteristics can reflect different roles in the pathogenesis of canine gastric disease. #
Uploads
Papers by Giovanni Cattoli