The mission of the Microbiology unit is to provide clinical and reference bacteriological services to public and private laboratories in North Carolina. A wide variety of specimen types are examined. Many of the services performed here are available only at the NCSLPH and the Centers for Disease Control and Prevention (CDC) in Atlanta, GA.
Botulism (Clostridium botulinum)
The SLPH does not perform botulism-related testing. Cases of suspected botulism constitute a health emergency and are handled according to protocols of the Division of Epidemiology and the CDC.
Specimens for isolation or polymerase chain reaction (PCR) molecular screening for Bordetella pertussis in suspected cases of whooping cough are accepted from public and private health care providers. Only symptomatic contacts of diagnosed cases of pertussis are recommended for Bordetella examination, since a carrier state in asymptomatic persons has not been demonstrated as an important source of transmission. Reference cultures are accepted for confirmation of Bordetella pertussis, B. parapertussis and B. bronchiseptica. Consultation and bench training are provided upon request.
Cholera (Vibrio cholerae)
Strains of Vibrio cholerae possessing the somatic 01 antigen (V. cholerae:01) are associated with epidemic cholera, while those lacking this antigen (V. cholerae non-01, non-cholera vibrio), cause sporadic diarrheal disease and do not present a public health threat. Although cholera is not endemic in the U.S., cases may be imported by travelers returning from countries where the disease is prevalent. Sporadic cases of non-cholera gastroenteritis are associated with salt water exposure or consumption of raw or insufficiently cooked contaminated seafood.Diphtheria
Diphtheria is an upper respiratory tract illness caused by Corynebacterium diphtheria, a facultative anaerobic, Gram-positive bacteria.
Diphtheria is a contagious disease spread by direct physical contact or breathing the aerosolized secretions of infected individuals. Historically quite common, diphtheria has largely been eradicated in industrialized nations through widespread vaccination. The diphtheria-pertussis-tetanus (DPT) vaccine is recommended for all school-age children in the U.S., and boosters of the vaccine are recommended for adults, since the benefits of the vaccine decrease with age without constant re-exposure; they are particularly recommended for those traveling to areas where the disease has not been eradicated.
Clinical specimens for the isolation of enteric microorganisms are accepted only from public health care providers. Fecal specimens are examined for the presence of enteric pathogens including Salmonella typhi, other Salmonella serotypes, Shigella, Campylobacter, Yersinia and Escherichia coli (E. coli) 0157:H7, and other Shiga-toxin producing E. coli (STEC). Specimens from contacts of patients culture-positive for communicable enteric pathogens are tested following recommendations in Control of Communicable Diseases in Man. Reference isolates are accepted from public and private health care providers for identification and/or serotyping. The SLPH is the North Carolina serotyping center for Salmonella, Shigella and E. coli 0157:H7 and participates in the national surveillance programs of the CDC.
Food samples are examined for the presence of disease-producing bacteria only in cases of documented illness involving at least two persons. Foods suspected of adulteration or those not associated with illness are referred to the Food and Drug Administration through the N.C. Department of Agriculture. Food samples are accepted only when submitted through the local health department. The local health department should always be notified of suspected foodborne illness so that an epidemiological investigation can be conducted. Feces and other specimens relating to foodborne disease also are accepted. The Microbiology Unit should be alerted at (919)733-7367 as soon as possible after illness is reported. Contact the Epidemiology and Communicable Disease Section at (919)733-3419 for assistance in investigating foodborne disease.
Legionellosis is diagnosed by a combination of culture and direct fluorescent antibody (DFA) staining in conjunction with the patient´s clinical history. Culture is the recommended diagnostic procedure. The Bacteriology Unit offers culture and DFA staining of clinical specimens and reference cultures to public and private health care providers. Urinary antigen detection and DNA probe procedures are not available in this Laboratory. Environmental specimens are not tested. Consultation and bench training are available upon request.
Methicillin Resistant Staph Aureus
Case must be outbreak related for the isolate to be accepted by the CDC for Pulsed Field Gel Electrophoresis (PFGE). If there are multiple isolates, please send in batches to the NCSLPH and include a letter documenting the outbreak with the first batch of isolates. Send a NCSLPH requisition DHHS 4121 for each isolate submitted. For questions, call CDC (404) 639-3570.
Specimens for isolation and identification of all Mycobacterium species (including Mycobacterium tuberculosis complex and other nontuberculous mycobacteria) are accepted from public and private health care providers. Positive isolations or identifications are reported to the Tuberculosis Control Branch, Epidemiology and Communicable Disease Section in accordance with State Law.
Clinical specimens of skin, hair, and nails are no longer accepted. Specimens for isolation and identification of medically important fungi from body tissues and fluids are accepted from public and private health care providers. Reference cultures are also accepted for identification of yeasts, molds, and aerobic actinomycetes. Fungal specimens for "routine" culture are not accepted; limit cultures to those actually implicated in fungal disease. Routine antimicrobial susceptibility testing is not performed in this laboratory. Consultation and bench training in mycology are provided upon request.
Clinical specimens such as cervical, rectal or throat swabs are not accepted by the SLPH for primary isolation of Neisseria gonorrhoea (GC). Primary culture is available through the local health department Sexually Transmitted Disease (HIV/STD) Program. Reference cultures are accepted from public and private health care providers for confirmation. Cultures may be forwarded to the CDC for antimicrobial susceptibility studies in special circumstances.
Please note: Neisseria sp. die easily and should be freshly subbed to a chocolate slant or transport systems such as the Jembec plate. Incubation for 18 to 24 hours prior to transport enhances survival. Do not ship on a friday or holiday weekend. Write "DO NOT REFRIGERATE" on the outside of the package.
Diagnostic specimens for examination for the presence of human parasites are accepted from public health care providers only. Diagnostic specimens for parasitologic examination are accepted only from symptomatic patients. Reference specimens for confirmation of parasite identity or further identification with the exception of blood are accepted from all laboratories.
Special and Atypical Bacteriology
The Special and Atypical Bacteriology lab serves primarily as a referral laboratory for bacteria that are unusual or difficult to identify and includes the examination of a wide variety of microorganisms including the following: Bordetella, Corynebacterium, Haemophilus, Legionella, Neisseria, Pasteurella, Pseudomonas and similar organisms and "unclassified" bacteria. Pure isolates are required for identification or serotyping. Specimens are accepted from public and private health care providers. Cultures from animal or environmental sources must be associated with human illness. Anaerobic cultures and antimicrobial susceptibility testing are not performed in this laboratory. Consultation and bench training are provided upon request.
Steptococcus pneumoniae typing:
Unless there is an outbreak situation, these isolates are no longer routinely accepted by the CDC unless discussed in advance with CDC to obtain prior approval for testing. Please call the Streptococcus Laboratory at 404-639-1237. Isolates should be submitted on a chocolate slant with a completed CDC 50.34 DASH Form (PDF, 2.5 MB) including documentation of prior communication with CDC.
Vancomycin Intermediate Staph aureus/Vancomycin Resistant Staph aureus (VISA/VRSA):
These isolates should be sent to the NCSLPH for minimum inhibitory concentrations (MICs) and resistant organisms will be sent to the CDC for final confirmation. VISA and VRSA are reportable to both the CDC and the state of North Carolina through the Communicable Disease Branch at 919-733-3419. Subculture and save copy of isolate in-house.
To contact the Microbiology Unit of the NC State Laboratory, call (919) 733-7367.