LETTERS

(7). The remaining 1 is from Japan and *National Institute of Animal Health, Tsuku- Address for correspondence: Tsutomu Sekizaki, assigned to ST28 (8). Unlike in previ- ba, Ibaraki, Japan; †Chiang Mai University, National Institute of Animal Health, 3-1-5 ous reports, 80% of the human clinical Chiang Mai, Thailand; ‡Northern District Kannondai, Tsukuba, Ibaraki 305-0856, Japan; isolates (16 isolates) characterized in Livestock Health and Hygiene Offi ce, Mito, email: [email protected] this study were assigned to the ST27 Ibaraki, Japan; §Seibu Livestock Hygiene complex. Although previous studies Service Center, Tonami, Toyama, Japan; suggested that members of the ST27 ¶Lamphun Provincial Hospital, Lamphun, complex may have lower potential to Thailand; #Kitasato University, Towada, cause invasive diseases in swine (7), Aomori, Japan; and **Gifu University, Gifu, all the isolates were isolated from Gifu, Japan blood or cerebrospinal fl uid of the patients, suggesting a high degree of References suis invasiveness (Table). Because it is 1. Staats JJ, Feder I, Okwumabua O, Chen- , United unknown whether the ST27 complex gappa MM. Streptococcus suis: past and States is also dominant among isolates from present. Vet Res Commun. 1997;21: diseased in Thailand, future sur- 381–407. To the Editor: Streptococcus 2. Vecht U, Wisselink HJ, van Dijk JE, suis, commensal and opportunistic veillance will be necessary to know Smith HE. Virulence of Streptococcus the situation in pigs. However, our suis type 2 strains in newborn germfree of swine, and prevalent data indicate that the ST27 complex pigs depends on phenotype. Infect Immun. zoonotic agents worldwide, are α-he- is another clonal group that should be 1992;60:550–6. molytic gram-positive cocci with 35 3. Jacobs AAC, Loeffen PLW, van den Berg different serotypes (1). In humans, S. assessed for its importance for human AJG, Storm PK. Identifi cation, purifi ca- infection. Because mrp, epf, and sly tion, and characterization of a thiol-acti- suis infection has been associated with are not appropriate as virulence mark- vated hemolysin (suilysin) of Streptococ- bacterial meningitis, septic shock, ar- ers for the ST27 complex members, cus suis. Infect Immun. 1994;62:1742–8. thritis, pneumonia, endocarditis, en- 4. Smith HE, Damman M, van der Velde dophthalmitis, and spontaneous bacte- development of novel virulence mark- J, Wagenaar F, Wisselink HJ, Stock- ers will be needed for effi cient dis- hofe-Zurwieden N, et al. Identifi cation rial peritonitis (2,3). Most at risk are crimination of S. suis strains virulent and characterization of the cps locus of those who handle or eat undercooked for humans. Streptococcus suis serotype 2: the capsule pork, e.g., farm workers, butchers, protects against phagocytosis and is an and slaughterhouse workers (4). Most important virulence factor. Infect Immun. 1999;67:1750–6. cases have been reported in Europe or This study made use of the Strepto- 5. Vecht U, Wisselink HJ, Jellema ML, Smith Southeast Asia (2,3). Meningitis, fi rst coccus suis Multilocus Sequence Typing HE. Identifi cation of two proteins associ- recognized in 1968 in Denmark (1), is website (http://ssuis.mlst.net); this site is ated with virulence of Streptococcus suis the most common clinical manifesta- hosted at Imperial College and develop- type 2. Infect Immun. 1991;59:3156–62. 6. Gottschalk M, Lebrun A, Wisselink H, tion of human infection with S. suis. A ment is funded by the Wellcome Trust. The Dubreuil JD, Smith H, Vecht U. Produc- case of S. suis meningitis in a farm- study was supported by a grant-in-aid from tion of virulence-related proteins by Cana- er was reported in the United States the Zoonoses Control Project of the Min- dian strains of Streptococcus suis capsular (5). Here, we describe another case in istry of Agriculture, Forestry and Fisher- type 2. Can J Vet Res. 1998;62:75–9. 7. King SJ, Leigh JA, Heath PJ, Luque I, Tar- a 60-year-old man from San Francisco ies of Japan and the Endowment Fund for radas C, Dowson CG, et al. Development who had consumed raw pork while Medical Research, Faculty of Medicine, of a multilocus sequence typing scheme traveling in the Philippines. Chiang Mai University. for the pig Streptococcus suis: In June 2003, this man became identifi cation of virulent clones and po- tential capsular serotype exchange. J Clin ill with fever, diaphoresis, headache, Daisuke Takamatsu,* Microbiol. 2002;40:3671–80. nausea, and anorexia. He had just re- Korawan Wongsawan,† 8. Chang B, Wada A, Ikebe T, Ohnishi M, turned from a 7-month vacation in the Makoto Osaki,* Mita K, Endo M, et al. Characteritics of Philippines. Three days after symp- Streptococcus suis isolated from patients Hiroto Nishino,‡ Tomono Ishiji,§ in Japan. Jpn J Infect Dis. 2006;59:397–9. toms onset, his physician prescribed Prasit Tharavichitkul,† 9. Ye C, Zhu X, Jing H, Du H, Segura M, doxycycline. Symptoms continued Banyong Khantawa,† Zheng H, et al. Streptococcus suis se- and he was admitted to a local hospi- Achara Fongcom,¶ quence type 7 outbreak, Sichuan, China. tal 5 days later with a fever of 38.9°C, Emerg Infect Dis. 2006;12:1203–8. Shinji Takai,# 10. Silva LMG, Baums CG, Rehm T, Wis- nuchal rigidity, headache, and general and Tsutomu Sekizaki*, ** selink HJ, Goethe R, Valentin-Weigand malaise. P. Virulence-associated gene profi ling of The patient described no recent Streptococcus suis isolates by PCR. Vet contact with sick persons; past medical Microbiol. 2006;115:117–27.

Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 14, No. 1, January 2008 183 LETTERS history was unremarkable. On physi- sensitive to (MIC = 0.03), tact with pigs or eating undercooked cal examination, he was somnolent but ceftriaxone, and vancomycin but resis- pork products. Invasion of the blood- fully oriented, with no focal fi ndings tant to tetracycline and clindamycin. stream can occur directly through skin on neurologic examination and only Antimicrobial therapy was changed to abrasions or the oral or respiratory slight nuchal rigidity. He had a leuko- penicillin G, 24 million units intrave- route (6). Once bloodborne, S. suis cyte count of 21,000/mm3, including nously per day. can cause toxic shock syndrome and 16,400/mm3 neutrophils. Cerebrospinal On hospital day 5, the patient (7). The mechanism by which fl uid (CSF) showed leukocyte count of complained of hearing loss in his left the organism traverses the blood- 487/μL with 80% polymorphonuclear ear. Results of nasopharyngeal endos- brain barrier to cause meningitis is not cells and 18% lymphocytes, and glu- copy were negative. By hospital day 7, known, although bacterial toxins and cose and protein levels <20 mg/dL and the organism was identifi ed by the API host infl ammatory mediators may play <167 mg/dL, respectively. Gram stain 20 Strep System (bioMerieux, Marcy a role (8). of CSF showed gram-positive cocci l’Etoile, France) as S. suis serotype 2. Hearing loss from S. suis men- in pairs. Empiric therapy (ceftriaxone, The patient subsequently stated that he ingitis, although not specifi c for the vancomycin, and ampicillin) for bacte- was a butcher with a culinary prefer- organism, occurs frequently in half to rial meningitis was begun. Computed ence for partially cooked pork, which two thirds of patients and can be irre- tomographic scan of the head showed he had eaten in the Philippines until versible (3,7,9). Administering dexa- only sinusitis; fi ndings of chest radio- the week prior to onset of symptoms. methasone may ameliorate hearing graph and transesophageal echocardio- On hospital day 9, a formal audiology loss in some cases (10). Penicillin G gram were negative. evaluation showed severe bilateral is the preferred treatment for S. suis On hospital day 2, blood cultures sensorineural high-frequency hearing infection, although penicillin resis- grew gram-positive cocci in pairs and loss (–70 dB). The patient completed tance has emerged in S. suis because chains (Figure). The organism was a 10-day course of parenteral antimi- of the farm practice of supplementing catalase-negative, bile esculin-nega- crobial drugs and was discharged on feeds with antimicrobial drugs. As an tive, and pyrrolidonyl aminopeptidase- continued oral therapy with close fol- alternative therapy, vancomycin may negative, consistent with Streptococ- lowup. Two months after discharge, be used (6). Thus, empiric therapy for cus spp. A latex agglutination test did the patient reported much improved adult bacterial meningitis (ceftriax- not detect Streptococcus pneumoniae hearing without other sequelae. one and vancomycin with or without antigen. Antimicrobial susceptibility Most S. suis infections occur in ampicillin) would likely be suffi cient testing showed that the isolate was older men and patients who report con- to treat S. suis meningitis. Although the death rate from this disease can be high, varying from 7% in one study (3) to 30% in another (6), infection can be prevented by treating abra- sions promptly, wearing gloves when handling pork, adhering to proper hand washing techniques, and suffi - ciently cooking pork products (3). S. suis infection may go unrec- ognized since many laboratories do not routinely speciate α-hemolytic streptococci. However, in the United States, specialized tests such as the API 20 Strep System (API System; La Balme Les Grottes, Montalieu-Ver- cieu, France) or reference laboratories are readily available for diagnosis of all unidentifi ed streptococci. In severe cases where infection is suspected, physicians may request that laborato- ries conduct defi nitive tests to identify the organism. In countries that lack Figure. Gram-positive cocci in pairs in a 60-year-old man with meningitis. Magnifi cation x1,000. these resources and where under-

184 Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 14, No. 1, January 2008 LETTERS cooked pork is a diet staple, underdi- Address for correspondence: Gregory T. Lee, common viruses (herpesviruses, ade- agnosis of S. suis infection is likely. Department of Radiology, Harbor-UCLA novirus, hepatitis virus, and coxsackie Greater understanding of this organ- Medical Center, Box 27, 1000 West Carson virus). For both of these groups, DNA ism and its disease spectrum would St, Torrance, CA 90509-2910, USA; email: was extracted for analysis from se- promote earlier diagnosis and preven- [email protected] rum specimens and peripheral blood tion of sequelae. mononuclear cells (PBMCs). Groups 3 and 4 comprised recipients of kid- Gregory T. Lee,* ney and allogeneic BM/peripheral Charles Y. Chiu,* blood stem cell (PBSC) transplants, Barbara L. Haller,† for which DNA was extracted from Patricia M. Denn,† serum specimens collected at 6 and Christopher S. Hall,* 12 months, respectively, after trans- and Julie L. Gerberding‡ Parvoviruses in plantation. The nested PCR method *University of California San Francisco, San Blood Donors and was used to amplify a shared sequence Francisco, California, USA; †San Francisco Transplant of PARV4 and its variant PARV5 General Hospital, San Francisco, Califor- and was specifi c for the open read- nia, USA; and ‡Centers for Disease Control Patients, Italy ing frame 1. First step PCR was per- and Prevention, Atlanta, Georgia, USA To the Editor: Parvoviruses formed as previously described (2) (PARV) 4 and 5 are 2 genotypes of with a sensitivity of 1–10 copies, on References a novel human parvovirus, with 92% 1 μg PBMC DNA and on one fi fth of DNA extracted from 0.25 mL of serum. 1. Staats JJ, Feder I, Okwumabua O, Chen- nucleotide identity, identifi ed in the gappa MM. Streptococcus suis: past and plasma sample of a patient screened Primers for second round PCR were present. Vet Res Commun. 1997;21:381– for acute HIV infection and in samples PV4NS1Fn2 (5′-GTTGATGGYCCT- 407. of manufactured plasma pools (1,2). GTGGTTAG-3′) and PV4NS1Rn2 2. Kopic J, Paradzik MT, Pandak N. Strepto- (5′-CCTTTCATATTCAGTTCCT- coccus suis infection as a cause of severe Recently, PARV4 and PARV5 were illness: 2 cases from Croatia. Scand J In- identifi ed in blood samples from 3 of GTTCAC-3′). All positive results were fect Dis. 2002;34:683–4. 26 cadavers from the United Kingdom, confi rmed by direct sequencing. 3. Arends JP, Zanen HC. Meningitis caused all of whom were positive for hepatitis We found 3 positive case-patients, by Streptococcus suis in humans. Rev In- including 2 renal transplant recipients fect Dis. 1988;10:131–7. C virus RNA and had a history of in- 4. Dupas D, Vignon M, Geraut C. Strepto- travenous drug use (3). PARV4/5 were and 1 patient with a suspected viral coccus suis meningitis: a severe noncom- also found in bone marrow (BM) and disease; none of the blood donors test- pensated occupational disease. J Occup lymphoid tissues from 17 of 24 HIV- ed positive on single-round PCR. On Med. 1992;34:1102–5. nested PCR, 1 blood donor had posi- 5. Willenburg KS, Sentochnik DE, Zakods positive cadavers from Scotland (4) RN. Human Streptococcus suis menin- and in BM aspirates from 16 of 35 Ital- tive results; the positivity rate did not gitis in the United States. N Engl J Med. ian patients with AIDS (5). Little or no increase in the other groups (Table). In 2006;354:1325. information is available about the epi- the fi rst 2 groups, PARV4/5 sequences 6. Vilaichone RK, Vilaichone W, Nunthap- were detected only in the serum sam- isud P, Wilde H. Streptococcus suis in- demiology and clinical correlates of fection in Thailand. J Med Assoc Thai. infection with these novel viruses. To ples, not in the PBMCs collected at the 2002;85(Suppl 1):S109–17. provide insights into their pathogenic same time. These sequences suggest 7. Tang J, Wang C, Feng Y, Yang W, Song potential in vivo, we assessed the fre- that PBMCs are not a major site of H, Chen Z, et al. Streptococcal toxic shock viral replication. Similar to B19 infec- syndrome caused by Streptococcus suis quency of PARV4/5 viremia in healthy serotype 2. PLoS Med. 2006;3:e151. patients, transplant patients, and those tion, which is rarely reactivated in the 8. Vadeboncoeur N, Segura M, Al-Numani with suspected viral disease. setting of BM/PBSC transplantation D, Vanier G, Gottschalk M. Pro-infl am- We performed a retrospective (6,7), none of the BM/PBSC trans- matory cytokine and chemokine release plant patients were PARV4/5 positive. by human brain microvascular endothelial molecular study for the presence of cells stimulated by Streptococcus suis se- PARV4/5 sequences in 4 groups of The detection of PARV4/5 sequences rotype 2. FEMS Immunol Med Microbiol. 417 Italian HIV-negative persons. in the serum collected at 12 months 2003;35:49–58. Group 1 consisted of 100 blood donors after transplantation was not associ- 9. Kay R, Cheng AF, Tse CY. Streptococ- ated with the occurrence of any symp- cus suis infection in Hong Kong. QJM. recruited from the Transfusion Centre 1995;88:39–47. of Modena (northern Italy); group 2, toms in the 2 renal recipients. Of note, 10. de Gans J, van de Beek D. Dexamethasone 84 patients with hematologic diseases the available serum samples collected in adults with bacterial meningitis. N Engl showing clinical signs of viral etiol- from both recipients before transplan- J Med. 2002;347:1549–56. ogy but negative results for the most tation, and at 6 and 24 months after

Emerging Infectious Diseases • www.cdc.gov/eid • Vol. 14, No. 1, January 2008 185