31 July = 2005

Outbreak in = Sichuan:=20 Is Strep Suis the only infection?

This = month an=20 outbreak of a rapidly progressive, sometimes fatal disease has = been=20 reported in Sichuan, China primarily in persons in contact = with pigs=20 and pork products. The cause has been preliminarily identified as = the=20 gram-positive bacteria "Streptococcus (Strep) suis". = Certain=20 characteristics, however, raise the possibility that in addition = to Strep=20 suis a 2nd infectious disease agent could be present and thus = further=20 laboratory testing and clinical information is=20 needed.

Prior = reports of=20 Strep suis causing human illness have been small in size and often = focused=20 clinically on patients who develop meningitis, = sometimes with=20 secondary hearing loss. Some patients in the literature have also = been=20 reported to have toxic shock syndrome, which can cause = desquamation=20 of large parts of the skin. In the current outbreak in = several=20 cities in Sichuan province, however, meningitis is reportedly rare = and=20 skin changes are most striking for subcutaneous hemorrhage, not a = typical=20 skin finding for Strep suis infection.

Conceivably, the=20 strep bacteria has mutated and now causes a cutaneous hemorrhagic = disease,=20 but preliminary reports form China on the genetic sequencing of = this=20 organism are reported in the media (South China Morning Post and = China=20 Daily) a snot demonstrating any mutations.

To = date, there is=20 no report of person-to-person spread of this apparent Strep suis=20 infection. Most cases are suspected to be due to direct contact = with pigs=20 and pork products. In addition, there is no report of multidrug = antibiotic=20 resistance. However, a few patients have now been reported outside = Sichuan=20 province, such as in Hong Kong and Guangdong province, and thus = constant=20 vigilance and more detailed epidemiologic surveillance is needed.=20

If H5N1 = avian=20 influenza were a co-infection with the Strep suis, then one would = expect=20 many more cases to have occurred by now, and the identification of = this=20 now-familiar virus by Chinese laboratory researchers to have been=20 reported. The involvement of the WHO in the investigation of this = outbreak=20 is welcomed.

Daniel.R.Lucey,=20 MD, MPH

Adjunct = Professor=20 of Microbiology and Immunology

Georgetown=20 University School of medicine

Director, Centre=20 for Biologic Counterterrorism and Emerging = Diseases

Washington=20 Hospital Center Department of Emergency = Medicine

Wahsington,=20 DC