Parvoviruses: A Future Challenge

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Parvoviruses A Future Challenge?

• Nicola Boschetti, ZLB Behring AG, Bern

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Emerging Viruses
Definition
Viruses that have newly appeared in a population
or have existed previously but are rapidly
increasing in incidence or geographic
range. Morse, S.S. (1995), Emerg Infect Dis 1,
7-15 ... and those which previously existed but
come into our awareness as etiological agent of
some disease.
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Emerging Viruses
Viruses depend on favorable hosts in a favorable
environment.
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Carnivore Parvoviruses
FPV Feline ParvovirusRPV Raccoon
ParvovirusMEV Mink Enteritis VirusBFPB Blue
Fox Parvovirus
Parrish CR, ASM News (1997) 63, 307
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Carnivore Parvoviruses
The emergent canine parvoviruses are
characterized by specific amino acid changes in
and around a raised region of the capsid termed
the threefold spike. Structural and mutational
studies suggest that this region binds the
cellular transferrin receptor and controls host
range.
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Sequence Variability
Sequence variability of human erythroviruses at
threefold symmetry axis.
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Recently discovered Parvoviruses

• BPV2 BPV3

• humanBocavirus

• PARV4

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Virus safety of biological / biotechnological
products
Potential Viral Contamination
Approaches (Prevention Elimination)
Biological Source Material
Selection
Testing
Contaminated Raw Materials
Elimination
Adventitiously introduced in manufacturing
cGMP
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Virus elimination mechanisms
Rough classification of viruses

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Virus elimination principles used in
manufacturing
Partitioning
Inactivation S/D, Caprylate
Pasteurization, low pH
Virusfiltration
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Conclusion

• (Parvo) viruses are evolving.
• Novel (parvo) viruses are/will be discovered.
• Current Biologicals have a high safety standard
  basing on four complementary approaches.
• Proactive investigations on (small non-enveloped)
  viruses in order to discover such viruses
  entering the source and raw materials should
  continue.

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Thank you for listening!