Pneumococcal colonization and invasive disease studied in a porcine model.
BACKGROUND
Streptococcus pneumoniae, a Gram-positive bacterium carried in the human nasopharynx, is an important human pathogen causing mild diseases such as otitis media and sinusitis as well as severe diseases including pneumonia, meningitis and sepsis. There is a strong resemblance between the anatomy, immunology and physiology of the pig and human species. Furthermore, there are striking similarities between S. suis pathogenesis in piglets and S. pneumoniae pathogenesis in humans. Therefore, we investigated the use of piglets as a model for pneumococcal colonization and invasive disease.


RESULTS
Intravenous inoculation of piglets with an invasive pneumococcal isolate led to bacteraemia during 5 days, showing clear bacterial replication in the first two days. Bacteraemia was frequently associated with fever and septic arthritis. Moreover, intranasal inoculation of piglets with a nasopharyngeal isolate led to colonization for at least six consecutive days.


CONCLUSIONS
This demonstrates that central aspects of human pneumococcal infections can be modelled in piglets enabling the use of this model for studies on colonization and transmission but also on development of vaccines and host-directed therapies. Moreover this is the first example of an animal model inducing high levels of pneumococcal septic arthritis.
Central Veterinary Institute, part of Wageningen UR, Lelystad, The Netherlands. astrid.degreeff@wur.nl.
Astrid
http://orcid.org/0000-0002-2498-3668
A
de Greeff
Laboratory of Paediatric Infectious Diseases, Department of Paediatrics, Radboud University Medical Center, Nijmegen, The Netherlands.|Raboud Institute for Molecular Life Sciences, Nijmegen, The Netherlands.
Saskia
S
van Selm
Central Veterinary Institute, part of Wageningen UR, Lelystad, The Netherlands.
Herma
H
Buys
Central Veterinary Institute, part of Wageningen UR, Lelystad, The Netherlands.
José F
JF
Harders-Westerveen
Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands.
Rahajeng N
RN
Tunjungputri
Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands.
Quirijn
Q
de Mast
Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands.
Andre J
AJ
van der Ven
Central Veterinary Institute, part of Wageningen UR, Lelystad, The Netherlands.
Norbert
N
Stockhofe-Zurwieden
Laboratory of Paediatric Infectious Diseases, Department of Paediatrics, Radboud University Medical Center, Nijmegen, The Netherlands.|Raboud Institute for Molecular Life Sciences, Nijmegen, The Netherlands.
Marien I
MI
de Jonge
Central Veterinary Institute, part of Wageningen UR, Lelystad, The Netherlands.
Hilde E
HE
Smith
D000818:Animals; D001170:Arthritis, Infectious / Q000382:microbiology; D016470:Bacteremia / Q000382:microbiology / Q000473:pathology*; D004195:Disease Models, Animal; D005334:Fever / Q000209:etiology; D006801:Humans; D009305:Nasopharynx / Q000382:microbiology; D011008:Pneumococcal Infections / Q000382:microbiology / Q000473:pathology / Q000662:veterinary*; D013296:Streptococcus pneumoniae / Q000472:pathogenicity*; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology* / Q000473:pathology
Animal model; Colonization; Pigs; Streptococcus pneumoniae