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Antimicrobial resistance and prudent drug use for Streptococcus suis

Published online by Cambridge University Press:  20 May 2013

Norma P. Varela ,
Pierre Gadbois ,
Claude Thibault ,
Marcelo Gottschalk ,
Paul Dick  and
Jeff Wilson
Norma P. Varela
Affiliation:
Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, Ontario, CanadaN1G 2W1 Novometrix Research Inc., RR 1, Moffat, Ontario, CanadaL0P 1J0
Pierre Gadbois
Affiliation:
Vétoquinol Canada Inc., 2000 Chemin Georges, Lavaltrie, Québec, CanadaJ0K 1H0
Claude Thibault
Affiliation:
Vétoquinol Canada Inc., 2000 Chemin Georges, Lavaltrie, Québec, CanadaJ0K 1H0
Marcelo Gottschalk
Affiliation:
Faculty of Veterinary Medicine, Université de Montréal, Québec, CanadaJ2S 2M2
Paul Dick
Affiliation:
Paul Dick and Associates, 326 Gordon Street, Guelph, Ontario, CanadaN1G 1X6
Jeff Wilson*
Affiliation:
Novometrix Research Inc., RR 1, Moffat, Ontario, CanadaL0P 1J0
*
*Corresponding author. E-mail: [email protected]
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Abstract

This paper reviews information on antimicrobial resistance patterns and prudent use of antimicrobials to reduce the impact and spread of resistant Streptococcus suis strains. S. suis is an important pathogen in swine, which can cause significant economic loss. Prudent use of antimicrobials for S. suis is essential to preserve the therapeutic efficacy of broad-spectrum antimicrobials and to minimize selection of resistant S. suis strains. Resistance of S. suis to antimicrobials commonly used in swine, including lincosamides, macrolides, sulphonamides, and tetracycline, has been documented worldwide, with resistance in up to 85% of strains. Among antimicrobials examined, resistance of S. suis has been demonstrated to be relatively low for penicillin (0–27%), ampicillin (0.6–23%), and ceftiofur (0–23%). For penicillin, this result may be due in part to the unique mechanism by which resistance is acquired through modifications in the structure of penicillin-binding proteins. Recommendations to control S. suis infection include focused and careful choice and appropriate use of antimicrobials, together with preventive measures intended to improve swine management.

Keywords

Streptococcus suisprudent useantimicrobial resistanceserotype 2
Type
Review Article
Information
Animal Health Research Reviews , Volume 14 , Issue 1 , June 2013 , pp. 68 - 77
Copyright
Copyright © Cambridge University Press 2013 

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References

Aarestrup, FM (1999). Association between the consumption of antimicrobial agents in animal husbandry and the occurrence of resistant bacteria among food animals. International Journal of Antimicrobial Agents 12: 279–285.CrossRefGoogle ScholarPubMed
Aarestrup, FM, Rasmussen, SR, Artursson, K and Jensen, NE (1998). Trends in the resistance to antimicrobial agents of Streptococcus suis isolates from Denmark and Sweden. Veterinary Microbiology 63: 71–80.CrossRefGoogle ScholarPubMed
Amass, SF, Struve, R, Clark, LK and Wu, CC (1996a). Cesarean section: a surgical method to derive pigs free of Streptococcus suis. Swine Health and Production 4: 196–198.Google Scholar
Amass, SF, Wu, CC and Clark, LK (1996b). Evaluation of antibiotics for the elimination of the tonsillar carrier state of Streptococcus suis in pigs. Journal of Veterinary Diagnostic Investigation 8: 64–67.CrossRefGoogle ScholarPubMed
Amass, SF, SanMiguel, P and Clark, LK (1997). Demonstration of vertical transmission of Streptococcus suis in swine by genomic fingerprinting. Journal of Clinical Microbiology 35: 1595–1596.CrossRefGoogle ScholarPubMed
Amass, SF, Stevenson, GW, Knox, KE and Reed, AJ (1999). Efficacy of an autogenous vaccine for preventing streptococcosis in piglets. Veterinary Medicine 94: 480–484.Google Scholar
Amass, SF, Stevenson, GW, Bryan, D, Vyverberg, BD, Huxford, TW, Knox, KE and Grote, LA (2000). Administration of a homologous bacterin to sows prefarrowing provided partial protection against streptoccosis in their weaned pigs. Journal of Swine and Health Production 8: 217–219.Google Scholar
Berthelot-Herault, F, Gottschalk, M, Labbe, A, Cariolet, R and Kobisch, M (2001). Experimental airborne transmission of Streptococcus suis capsular type 2 in pigs. Veterinary Microbiology 82: 69–80.CrossRefGoogle ScholarPubMed
Blackwell, T (2005). Effective treatment and handling of poor doing pigs in the finishing barn. In: Conference Proceedings, London Swine Conference, London, Ontario, p. 167.Google Scholar
Brisebois, LM, Charlebois, R, Higgins, R and Nadeau, M (1990). Prevalence of Streptococcus suis in four to eight week old clinically healthy piglets. Canadian Journal of Veterinary Research 54: 174–177.Google ScholarPubMed
Busque, P, Higgins, R, Caya, F and Quessy, S (1997). Immunization of pigs against Streptococcus suis serotype 2 infection using a live avirulent strain. Canadian Journal of Veterinary Research 61: 275–279.Google ScholarPubMed
Byra, C, Gadbois, P, Cox, WR, Gottschalk, M, Farzan, V, Bauer, SA and Wilson, JB (2011). Decreased mortality of weaned pigs with Streptococcus suis with the use of in-water potassium penicillin G. Canadian Veterinary Journal 52: 272–276.Google ScholarPubMed
Cain, D, Malouin, F, Dargis, M, Harel, J and Gottschalk, M (1995). Alterations in penicillin-binding proteins in strains of Streptococcus suis possessing moderate and high levels of resistance to penicillin. FEMS Microbiology Letters 130: 121–127.CrossRefGoogle ScholarPubMed
Cantin, M, Harel, J, Higgins, R and Gottschalk, M (1992). Antimicrobial resistance patterns and plasmid profiles of Streptococcus suis isolates. Journal of Veterinary Diagnostic Investigation 4: 170–174.CrossRefGoogle ScholarPubMed
Clifton-Hadley, FA, Alexander, TJ, Enright, MR and Guise, J (1984). Monitoring herds for Streptococcus suis type 2 by sampling tonsils of slaughter pigs. Veterinary Record 115: 562–564.CrossRefGoogle ScholarPubMed
Cloutier, G, D'Allaire, S, Martinez, G, Surprenant, C, Lacouture, S and Gottschalk, M (2003). Epidemiology of Streptococcus suis serotype 5 infection in a pig herd with and without clinical disease. Veterinary Microbiology 97: 135–151.CrossRefGoogle Scholar
Dee, SA and Corey, MM (1993). The survival of Streptococcus suis on farm and veterinary equipment. Swine Health and Production 1: 17–20.Google Scholar
Dee, SA, Carlson, AR, Winkelman, NL and Corey, MM (1993). Effect of management practices on the Streptococcus suis carrier rate in nursery swine. Journal of the American Veterinary Medical Association 203: 295–299.CrossRefGoogle ScholarPubMed
del Campo Sepulveda, EM, Altman, E, Kobisch, M, D'Allaire, S and Gottschalk, M (1996). Detection of antibodies against Streptococcus suis capsular type 2 using a purified capsular polysaccharide antigen-based indirect ELISA. Veterinary Microbiology 52: 113–125.CrossRefGoogle ScholarPubMed
Done, S and Burch, D (2007). Prevention and control of respiratory diseases excluding Mycoplasma Hyopneumoniae. Thai Journal of Veterinary Medicine 37: 9–20.CrossRefGoogle Scholar
Escudero, JA, San Millan, A, Catalan, A, de la Campa, AG, Rivero, E, Lopez, G, Dominguez, L, Moreno, MA and Gonzalez-Zorn, B (2007). First characterization of fluoroquinolone resistance in Streptococcus suis. Antimicrobial Agents and Chemotherapy 51: 777–782.CrossRefGoogle ScholarPubMed
Escudero, JA, San Millan, A, Gutierrez, B, Hidalgo, L, La Ragione, RM, AbuOun, M, Galimand, M, Ferrandiz, MJ, Dominguez, L, de la Campa, AG and Gonzalez-Zorn, B (2011). Fluoroquinolone efflux in Streptococcus suis is mediated by SatAB and not by SmrA. Antimicrobial Agents and Chemotherapy 55: 5850–5860.CrossRefGoogle Scholar
Federation of Veterinarians of Europe (2012). Antibiotic resistance & prudent use of antibiotics in veterinary medicine. [Available online at http://www.fve.org/news/publications/pdf/antibioen.pdf] [accessed 5 June 2012].Google Scholar
Feng, Y, Shi, X, Zhang, H, Zhang, S, Ma, Y, Zheng, B, Han, H, Lan, Q, Tang, J, Cheng, J, Gao, GF and Hu, Q (2009). Recurrence of human Streptococcus suis infections in 2007: three cases of meningitis and implications that heterogeneous S. suis 2 circulates in China. Zoonoses and Public Health 56: 506–514.CrossRefGoogle ScholarPubMed
Feng, Y, Zhang, H, Ma, Y and Gao, GF (2010). Uncovering newly emerging variants of Streptococcus suis, an important zoonotic agent. Trends in Microbiology 18: 124–131.CrossRefGoogle ScholarPubMed
Friendship, RM (2006). Antimicrobial drug use in swine. In: Giguere, S, Prescott, JF, Baggot, JD, Walker, RD and Dowling, PM (eds) Antimicrobial Therapy in Veterinary Medicine. Iowa: Blackwell Publishing, p. 538.Google Scholar
Galina, L, Vecht, U, Wisselink, HJ and Pijoan, C (1996). Prevalence of various phenotypes of Streptococcus suis isolated from swine in the U.S.A. based on the presence of muraminidase-released protein and extracellular factor. Canadian Journal of Veterinary Research 60: 72–74.Google ScholarPubMed
Ge, Y, Wu, J, Xia, Y, Yang, M, Xiao, J and Yu, J (2012). Molecular dynamics simulation of the complex PBP-2x with drug cefuroxime to explore the drug resistance mechanism of Streptococcus suis R61. PLoS ONE 7: e35941.CrossRefGoogle ScholarPubMed
Gottschalk, M and Segura, M (2000). The pathogenesis of the meningitis caused by Streptococcus suis: the unresolved questions 76: 259–272.CrossRefGoogle Scholar
Gottschalk, M (2004). Porcine Streptococcus suis strains as potential sources of infections in humans: an underdiagnosed problem in North America? Journal of Swine and Health Production 12: 197–199.Google Scholar
Gottschalk, M (2012). Streptococcosis. In: Zimmerman, JJ, Karriker, LA, Ramirez, A, Schwartz, KJ and Stevenson, GW (eds) Diseases of Swine, 10th edn. Iowa: Blackwell Publishing, pp. 841–855.Google Scholar
Gottschalk, M, Higgins, R, Jacques, M, Beaudoin, M and Henrichsen, J (1991a). Isolation and characterization of Streptococcus suis capsular types 9–22. Journal of Veterinary Diagnostic Investigation 3: 60–65.CrossRefGoogle ScholarPubMed
Gottschalk, M, Turgeon, P, Higgins, R, Beaudoin, M and Bourgault, AM (1991b). Susceptibility of Streptococcus suis to penicillin. Journal of Veterinary Diagnostic Investigation 3: 170–172.CrossRefGoogle ScholarPubMed
Gottschalk, M, Lebrun, A, Wisselink, H, Dubreuil, JD, Smith, H and Vecht, U (1998). Production of virulence-related proteins by Canadian strains of Streptococcus suis capsular type 2. Canadian Journal of Veterinary Research 62: 75–79.Google Scholar
Gottschalk, M, Segura, M and Xu, J (2007). Streptococcus suis infections in humans: the Chinese experience and the situation in North America. Animal Health Research Reviews 8: 29–45.CrossRefGoogle ScholarPubMed
Gottschalk, M, Xu, J, Calzas, C and Segura, M (2010). Streptococcus suis: a new emerging or an old neglected zoonotic pathogen? Future Microbiology 5: 371–391.CrossRefGoogle ScholarPubMed
Halbur, P, Thanawongnuwech, R, Brown, G, Kinyon, J, Roth, J, Thacker, E and Thacker, B (2000). Efficacy of antimicrobial treatments and vaccination regimens for control of porcine reproductive and respiratory syndrome virus and Streptococcus suis coinfection of nursery pigs. Journal of Clinical Microbiology 38: 1156–1160.CrossRefGoogle ScholarPubMed
Haleis, A, Alfa, M, Gottschalk, M, Bernard, K, Ronald, A and Manickam, K (2009). Meningitis caused by Streptococcus suis serotype 14, North America. Emerging Infectious Diseases 15: 350–352.Google Scholar
Hawkey, PM (2008). The growing burden of antimicrobial resistance. Journal of Antimicrobial Chemotherapy 62: 1–9.CrossRefGoogle ScholarPubMed
Health Canada (2002). Strategies to ensure prudent use of antimicrobial drugs. [Available online at http://www.hc-sc.gc.ca/dhp-mps/pubs/vet/amr-ram_final_report-rapport_06-27_cp-pc-eng.php#a8] [accessed 5 June 2012].Google Scholar
Hendriksen, RS, Mevius, DJ, Schroeter, A, Teale, C, Jouy, E, Butaye, P, Franco, A, Utinane, A, Amado, A, Moreno, M, Greko, C, Stark, KD, Berghold, C, Myllyniemi, AL, Hoszowski, A, Sunde, M and Aarestrup, FM (2008). Occurrence of antimicrobial resistance among bacterial pathogens and indicator bacteria in pigs in different European countries from year 2002–2004: the ARBAO-II study. Acta Veterinaria Scandinavica 50: 19.CrossRefGoogle ScholarPubMed
Higgins, R and Gottschalk, M (1999). Streptococcal diseases. In: Straw, BE, D'Allaire, S, Mengeling, WL and Taylor, DJ (eds) Diseases of Swine, 8th edn. Iowa: Blackwell Publishing, pp. 563–578.Google Scholar
Higgins, R and Gottschalk, M (2000). Distribution of Streptococcus suis capsular types in 1999. Canadian Veterinary Journal 41: 414.Google ScholarPubMed
Higgins, R, Gottschalk, M, Mittal, KR and Beaudoin, M (1990). Streptococcus suis infection in swine. A sixteen month study. Canadian Journal of Veterinary Research 54: 170–173.Google ScholarPubMed
Hoa, NT, Chieu, TT, Nghia, HD, Mai, NT, Anh, PH, Wolbers, M, Baker, S, Campbell, JI, Chau, NV, Hien, TT, Farrar, J and Schultsz, C (2011). The antimicrobial resistance patterns and associated determinants in Streptococcus suis isolated from humans in southern Vietnam, 1997–2008. BMC Infectious Diseases 11: 6.Google Scholar
Holt, ME, Enright, MR and Alexander, TJ (1990). Protective effect of sera raised against different fractions of Streptococcus suis type 2. Journal of Comparative Pathology 103: 85–94.CrossRefGoogle ScholarPubMed
Holtkamp, D, Rotto, H and Garcia, R (2007). The economic cost of major health challenges in large US swine production systems. In: Conference Proceedings, American Association of Swine Veterinarians. Orlando, FL, 3–6 March 2007. p. 85.Google Scholar
Hu, P, Yang, M, Zhang, A, Wu, J, Chen, B, Hua, Y, Yu, J, Chen, H, Xiao, J and Jin, M (2011). Comparative genomics study of multi-drug-resistance mechanisms in the antibiotic-resistant Streptococcus suis R61 strain. PLoS ONE 6: e24988. doi:10.1371/journal.pone.0024988.CrossRefGoogle ScholarPubMed
Jacobs, AA, van den Berg, AJ and Loeffen, PL (1996). Protection of experimentally infected pigs by suilysin the thio-activated haemolysin of Streptococcus suis. Vetinary Record 139: 225–228.CrossRefGoogle Scholar
Jensen, HE, Gyllensten, J, Hofman, C, Leifsson, PS, Agerholm, JS, Boye, M and Aalbaek, B (2010). Histologic and bacteriologic findings in valvular endocarditis of slaughter-age pigs. Journal of Veterinary Diagnostic Investigation 22: 921–927.CrossRefGoogle ScholarPubMed
Jensen, J and Dorseen van, CA (1957). Meningo-encephalitis bij vafkens door streptococcen. Tijdschrift voor diergeneeskunde 76: 815–832.Google Scholar
Jones, JE (1981). Experimental streptococcal endocarditis in the pig: the development of lesions 3 to 14 days after inoculation. Journal of Comparative Pathology 91: 51–62.CrossRefGoogle ScholarPubMed
Karstrup, CC, Jensen, HE, Aalbaek, B, Leifsson, PS, Boye, M and Agerholm, JS (2011). Endocarditis-associated brain lesions in slaughter pigs. Journal of Comparative Pathology 144: 289–295.Google Scholar
Kataoka, Y, Yoshida, T and Sawada, T (2000). A 10-year survey of antimicrobial susceptibility of Streptococcus suis isolates from swine in Japan. Journal of Veterinary Medical Science 62: 1053–1057.CrossRefGoogle ScholarPubMed
Keenliside, J, Gamroth, A, Bystrom, J and Perry, A (2006). Carcass trims – a look at arthritis and adhesions trims from severely affected herds. Advances in Pork Production 17: 187–192.Google Scholar
Kolar, M, Urbanek, K and Latal, T (2001). Antibiotic selective pressure and development of bacterial resistance. International Journal of Antimicrobial Agents 17: 357–363.Google Scholar
Lapointe, L, D'Allaire, S, Lebrun, A, Lacouture, S and Gottschalk, M (2002). Antibody response to an autogenous vaccine and serologic profile for Streptococcus suis capsular type 1/2. Canadian Journal of Veterinary Research 66: 8–14.Google Scholar
Li, Y, Martinez, G, Gottschalk, M, Lacouture, S, Willson, P, Dubreuil, JD, Jacques, M and Harel, J (2006). Identification of a surface protein of Streptococcus suis and evaluation of its immunogenic and protective capacity in pigs. Infection and Immunology 74: 305–312.CrossRefGoogle ScholarPubMed
Lun, ZR, Wang, QP, Chen, XG, Li, AX and Zhu, XQ (2007). Streptococcus suis: an emerging zoonotic pathogen. Lancet Infectious Diseases 7: 201–209.CrossRefGoogle ScholarPubMed
Ma, E, Chung, PH, So, T, Wong, L, Choi, KM, Cheung, DT, Kam, KM, Chuang, SK and Tsang, T (2008). Streptococcus suis infection in Hong Kong: an emerging infectious disease? Epidemiology and Infection 136: 1691–1697.CrossRefGoogle Scholar
MacInnes, JI and Desrosiers, R (1999). ‘Agents of the ‘ S. suis-ide diseases’ of swine: Actinobacillus S. suis, Haemophilus para S. suis, and Streptococcus suis’. Canadian Journal of Veterinary Research 63: 83–89.Google Scholar
MacInnes, JI, Gottschalk, M, Lone, AG, Metcalf, DS, Ojha, S, Rosendal, T, Watson, SB and Friendship, RM (2008). Prevalence of Actinobacillus pleuropneumoniae, Actinobacillus suis, Haemophilus parasuis, Pasteurella multocida, and Streptococcus suis in representative Ontario swine herds. Canadian Journal of Veterinary Research 72: 242–248.Google ScholarPubMed
Marie, J, Morvan, H, Berthelot-Hérault, F, Sanders, P, Kempf, I, Gauthier-Bouchardon, AV, Jouy, E and Kobisch, M (2002). Antimicrobial susceptibility of Streptococcus suis isolated from swine in France and from humans in different countries between 1996 and 2000. Journal of Antimicrobial Chemotherapy 50: 201–209.CrossRefGoogle ScholarPubMed
Martel, A, Baele, M, Devriese, LA, Goossens, H, Wisselink, HJ, Decostere, A and Haesebrouck, F (2001). Prevalence and mechanism of resistance against macrolides and lincosamides in Streptococcus suis isolates. Veterinary Microbiology 83: 287–297.CrossRefGoogle ScholarPubMed
McEwen, SA and Fedorka-Cray, PJ (2002). Antimicrobial use and resistance in animals. Clinical Infectious Diseases 34: 93–106.CrossRefGoogle ScholarPubMed
McKellar, QA, Baxter, P, Taylor, D and Bogan, JA (1987). Penicillin therapy of spontaneous streptococcal meningitis in pigs. Veterinary Record 121: 347–350.CrossRefGoogle ScholarPubMed
Messier, S, Lacouture, S and Gottschalk, M (2008). Distribution of Streptococcus suis capsular types from 2001 to 2007. Canadian Veterinary Journal 49: 461–462.Google ScholarPubMed
Michaud, S, Duperval, R and Higgins, R (1996). Streptococcus suis meningitis first case reported in Quebec. Canadian Journal of Infectious Diseases 7: 329–331.Google Scholar
National Animal Health Monitoring System (2006). Swine 2006 Part II: Reference of swine health and health management practices in the United States. [Available online at http://www.aphis.usda.gov/animal_health/nahms/swine/downloads/swine2006/Swine2006_dr_PartII.pdf] [accessed 10 April 2012].Google Scholar
Neumann, EJ, Ramirez, A and Schwartz, KJ (2009). Streptococcal infections. In: Neumann, EJ, Ramirez, A and Schwartz, KJ (eds) Swine Disease Manual, 4th edn. Iowa: American Association of Swine Veterinarians, pp. 39–40.Google Scholar
Osweiler, G (2003). Summary of selected swine assays and results for 2003 from the Iowa State University Veterinary Diagnostic Laboratory. In: Conference Proceedings, 11th Annual Swine Disease Conference for Swine Practitioners, Iowa, p. 188.Google Scholar
Palmieri, C, Varaldo, PE and Facinelli, B (2011). Streptococcus suis, an emerging drug-resistant animal and human pathogen. Frontiers in Microbiology 2: 235.CrossRefGoogle ScholarPubMed
Quessy, S, Dubreuil, JD, Caya, M, Letourneau, R and Higgins, R (1994). Comparison of pig, rabbit and mouse IgG response to Streptococcus suis serotype 2 proteins and active immunization of mice against the infection. Canadian Journal of Veterinary Research 58: 220–223.Google ScholarPubMed
Reams, RY, Glickman, LT, Harrington, DD, Bowersock, TL and Thacker, HL (1993). Streptococcus suis infection in swine: a retrospective study of 256 cases. Part I. Epidemiologic factors and antibiotic susceptibility patterns. Journal of Veterinary Diagnostic Investigation 5: 363–367.CrossRefGoogle ScholarPubMed
Reams, RY, Glickman, LT, Harrington, DD, Thacker, HL and Bowersock, TL (1994). Streptococcus suis infection in swine: a retrospective study of 256 cases. Part II. Clinical signs, gross and microscopic lesions, and coexisting microorganisms. Journal of Veterinary Diagnostic Investigation 6: 326–334.CrossRefGoogle ScholarPubMed
Reams, RY, Harrington, DD, Glickman, LT, Thacker, HL and Bowersock, TL (1996). Multiple serotypes and strains of Streptococcus suis in naturally infected swine herds. Journal of Veterinary Diagnostic Investigation 8: 119–121.Google Scholar
Sanford, SE, Schultz, R and Straw, B (1988). Streptococcus suis disease in pigs. [Available online at http://www.animalgenome.org/edu/PIH/118.html [accessed 10 April 2011].Google Scholar
Smith, HE, Vecht, U, Wisselink, HJ, Stockhofe-Zurwieden, N, Biermann, Y and Smits, MA (1996). Mutants of Streptococcus suis types 1 and 2 impaired in expression of muramidase-released protein and extracellular protein induce disease in newborn germfree pigs. Infection and Immunity 64: 4409–4412.CrossRefGoogle ScholarPubMed
Smith, TC, Capuano, AW, Boese, B, Myers, KP and Gray, GC (2008). Exposure to Streptococcus suis among US swine workers. Emerging Infectious Diseases 14: 1925–1927.CrossRefGoogle ScholarPubMed
Staats, JJ, Feder, I, Okwumabua, O and Chengappa, MM (1997). Streptococcus suis: past and present. Veterinary Research Communications 21: 381–407.CrossRefGoogle ScholarPubMed
Strangmann, E, Froleke, H and Kohse, KP (2002). Septic shock caused by Streptococcus suis: case report and investigation of a risk group. International Journal of Hygiene and Environmental Health 205: 385–392.CrossRefGoogle ScholarPubMed
Thanawongnuwech, R, Brown, GB, Halbur, PG, Roth, JA, Royer, RL and Thacker, BJ (2000). Pathogenesis of porcine reproductive and respiratory syndrome virus-induced increase in susceptibility to Streptococcus suis infection. Veterinary Pathology 37: 143–152.CrossRefGoogle ScholarPubMed
The Government of the Hong Kong Special Administrative Region (2005). Amendment to the Quarantine and Prevention of Disease Ordinance, Cap. 141. [Available online at http://www.chp.gov.hk/en/content/9/24/3648.html [accessed 3 April 2012].Google Scholar
Vela, AI, Moreno, MA, Cebolla, JA, Gonzalez, S, Latre, MV, Dominguez, L and Fernandez-Garayzabal, JF (2005). Antimicrobial susceptibility of clinical strains of Streptococcus suis isolated from pigs in Spain. Veterinary Microbiology 105: 143–147.Google Scholar
Walsh, B, Williams, AE and Satsangi, J (1992). Streptococcus suis type 2: pathogenesis and clinical disease. Reviews in Medical Microbiology 3: 65–71.Google Scholar
Wertheim, HF, Nghia, HD, Taylor, W and Schultsz, C (2009a). Streptococcus suis: an emerging human pathogen. Clinical Infectious Diseases 48: 617–625.Google Scholar
Wertheim, HF, Nguyen, HN, Taylor, W, Lien, TT, Ngo, HT, Nguyen, TQ, Nguyen, BN, Nguyen, HH, Nguyen, HM, Nguyen, CT, Dao, TT, Nguyen, TV, Fox, A, Farrar, J, Schultsz, C, Nguyen, HD, Nguyen, KV and Horby, P (2009b). Streptococcus suis, an important cause of adult bacterial meningitis in northern Vietnam. PLOS ONE 4: e5973.Google Scholar
Willenburg, KS, Sentochnik, DE and Zadoks, RN (2006). Human Streptococcus suis meningitis in the United States. New England Journal of Medicine 354: 1325.CrossRefGoogle ScholarPubMed
Wisselink, HJ, Reek, FH, Vecht, U, Stockhofe-Zurwieden, N, Smits, MA and Smith, HE (1999). Detection of virulent strains of Streptococcus suis type 2 and highly virulent strains of Streptococcus suis type 1 in tonsillar specimens of pigs by PCR. Veterinary Microbiology 67: 143–157.Google Scholar
Wisselink, HJ, Smith, HE, Stockhofe-Zurwieden, N, Peperkamp, K and Vecht, U (2000). Distribution of capsular types and production of muramidase-released protein (MRP) and extracellular factor (EF) of Streptococcus suis strains isolated from diseased pigs in seven European countries. Veterinary Microbiology 74: 237–248.CrossRefGoogle ScholarPubMed
Wisselink, HJ, Stockhofe-Zurwieden, N, Hilgers, LA and Smith, HE (2002). Assessment of protective efficacy of live and killed vaccines based on a non-encapsulated mutant of Streptococcus suis serotype 2. Veterinary Microbiology 84: 155–168.CrossRefGoogle ScholarPubMed
Zhang, C, Ning, Y, Zhang, Z, Song, L, Qiu, H and Gao, H (2008). In vitro antimicrobial susceptibility of Streptococcus suis strains isolated from clinically healthy sows in China. Veterinary Microbiology 131: 386–392.Google Scholar