Pathogen Safety Data Sheets: Infectious Substances – Neisseria spp.



NAME: Neisseria spp. (other than N. gonorrhoeae and N. meningitidis)


1) The majority of human-associated Neisseria species are non-pathogenic and are normal inhabitants of the upper respiratory tract. Human associated species include: N. gonorrhoeae, N. meningitidis, N. lactamica, N. cinerea, N. polysaccharea, N. mucosa, N. flavescens, N. sicca, N. subflava including the biovars subflava, flava, and perflava, and N. elongata subspecies elongata, glycolytica, and nitroreducens. Only N. gonorrhoeae and N. meningitidis are regarded as pathogens Footnote 1, Footnote 2.

2) Neisseria species associated with animals include: N. canis, N. weaveri (dogs), N. denitrificans (guinea pigs), N. macacae (rhesus monkey), N. dentiae (cows), and N. iguanae (lizards). Footnote 1, Footnote 2

CHARACTERISTICS: Neisseria spp. are gram-negative, non-motile, and non-spore-forming bacteria belonging to the family Neisseriaceae Footnote 1, Footnote 3. All members of the Neisseria spp., except the three subspecies of N. elongata and N. weaveri, occur as diplococcal bacteria with their adjacent sides flattened, resembling a kidney or coffee bean. The three subspecies of N. elongata and N. weaveri occur as medium to long, plump rods in pairs or short chains. All species are oxidase positive Footnote 1, Footnote 3, and all species except N. elongata subspecies nitroreducens and N. elongata subspecies elongata are catalase positive Footnote 3. Most species grow optimally at temperatures ranging between 35 to 37 °C, and growth is usually stimulated by carbon dioxide and humidity. Species are generally aerobic but some species may demonstrate growth under anaerobic conditions.


PATHOGENICITY/TOXICITY: Neisseria spp. are part of the commensal flora of mucosal membranes of humans and some animals, and are generally considered non-pathogenic except for N. gonorrhoea and N. meningitidis Footnote 1. Individuals with underlying medical conditions and/or immune suppression or deficiency may develop serious infections caused by the normally commensal Neisseria species. For example, N. lactamica had been reported to cause bacteramemic pneumonia and septicemia in immunocompromised individuals Footnote 4. N. cinerea is commonly isolated from the upper respiratory tract, but has also been isolated from other sites including the cervix, rectum, conjunctivae, blood and cerebrospinal fluid (CSF) Footnote 1. It has also been associated with rare cases of peritonitis Footnote 5, tonsillitis, lymphadenitis, proctitis, and pulmonary cavitation Footnote 6. N. flavescens and N. polysaccharea are found in the upper respiratory tract and the oropharynx (respectively) of humans, and are rarely associated with infectious processes Footnote 1. N. subflava, N. flava, N. perflava, N. mucosa, and N. sicca are found in the upper respiratory tract of humans and are occasional isolates from infectious processes, including endocarditis, bacteraemia, meningitis, pneumonia, empyema, pericarditis, peritonitis, septic arthritis, and liver abscess Footnote 1, Footnote 7-Footnote 10. N. elongata subspecies are found in the upper respiratory tract of humans and have been isolated from infectious processes, including endocarditis, septicaemia, and osteomyelitis Footnote 1, Footnote 11-Footnote 13. N. weaveri is part of the normal canine oral flora and has been isolated from a case of lower respiratory tract infection Footnote 14.

EPIDEMIOLOGY: Worldwide; part of the commensal flora of the upper respiratory tract and oropharynx of humans and some animals Footnote 1.

HOST RANGE: Humans and some animals (dogs, guinea pigs, rhesus monkeys, cows, and iguanid lizards) Footnote 1.


MODE OF TRANSMISSION: May be transmitted by contact with droplets and discharges from the nose and throat of infected persons; however, transmission is rare due to low virulence. May also be transmitted through bites by infected or colonized dogs (for N. weaveri).


COMMUNICABILITY: Not known to be readily transmitted from person-to-person due to low virulence.


RESERVOIR: Humans and some animals (dogs, guinea pigs, rhesus monkeys, cows, and iguanid lizards) Footnote 1.

ZOONOSIS: May be possible for animal pathogens; N. weaveri (found in dogs) has been isolated from wounds sites in humans as a result of dog bites Footnote 14.



DRUG SUSCEPTIBILITY: Neisseria spp. are susceptible to cefotaxime, ceftriaxone, and amoxicillin Footnote 6, Footnote 10, Footnote 15. Depending on the strains, some demonstrate intermediate to high resistance to penicillin and amoxicillin Footnote 15, Footnote 16. N. polysaccharea is resistant to vancomycin Footnote 1.

SUSCEPTIBILITY TO DISINFECTANTS: Gram-negative bacteria are generally susceptible to a number of disinfectants, including phenolic compounds, hypochlorites (1% sodium hypochlorite), alcohols (70% ethanol), formaldehyde (18.5 g/L; 5% formalin in water), glutaraldehyde, and iodines (0.075 g/L) Footnote 17.

PHYSICAL INACTIVATION: Bacteria are generally sensitive to moist heat (121 °C for at least 15 minutes) and dry heat (160 to 170 °C for at least 1 hour) Footnote 18.

SURVIVAL OUTSIDE HOST: Unknown; however, it may be similar to other members of the genus including N. gonorrhoeae and N. meningitis. N. gonorrhoeae is known to survive on different surfaces including toilet seats (brief periods of up to 2 hours) Footnote 3, Footnote 19, toilet paper (up to 3 hours)Footnote 19, slides (up to 17 hours), and towels (up to 24 hours). N. meningitidis does not survive well in the environment, but has been reported to survive on grass and plastic at ambient temperatures for hours to days Footnote 20.


SURVEILLANCE: Monitor for symptoms. Confirm by CSF or blood culture, or culture of biopsy specimens Footnote 6, Footnote 21.

Note: All diagnostic methods are not necessarily available in all countries.

FIRST AID/TREATMENT: Wash the exposed area with soap and warm water (omit soap if mucous membrane exposure). Treat with appropriate antibiotic therapy if required.




LABORATORY-ACQUIRED INFECTIONS: No cases of laboratory-acquired infection have reported up to date.

SOURCES/SPECIMENS: Throat and/or nasopharyngeal swabs and washings Footnote 21, pleural-effusion specimens, blood Footnote 9, Footnote 13, CSF Footnote 9, biopsy specimens Footnote 6, Footnote 10, and wound specimens Footnote 14.

PRIMARY HAZARDS: Accidental parenteral inoculation and/or ingestion of contaminated samples, and exposure of mucosal membranes via inhalation of infectious airborne secretions.



RISK GROUP CLASSIFICATION: Risk Group 2 Footnote 22. This risk group applies to the genus as a whole, and may not apply to every species within the genus.

CONTAINMENT REQUIREMENTS: Containment Level 2 facilities, equipment, and operational practices for work involving infectious or potentially infectious materials, animals, or cultures. These containment requirements apply to the genus as a whole, and may not apply to each species within the genus.

PROTECTIVE CLOTHING: Lab coat. Gloves when direct skin contact with infected materials or animals is unavoidable Footnote 23. Eye protection must be used where there is a known or potential risk of exposure to splashes.

OTHER PRECAUTIONS: All procedures that may produce aerosols, or involve high concentrations or large volumes should be conducted in a biological safety cabinet (BSC) Footnote 23. The use of needles, syringes, and other sharp objects should be strictly limited. Additional precautions should be considered with work involving animals or large scale activities.


SPILLS: Allow aerosols to settle and, while wearing protective clothing, gently cover spill with absorbent paper towels and apply an appropriate disinfectant, starting at the perimeter and working towards the centre. Allow sufficient contact time before clean up Footnote 23.

DISPOSAL: Decontaminate all wastes that contain or have come in contact with the infectious organism by autoclave, chemical disinfection, gamma irradiation, or incineration before disposing Footnote 23.

STORAGE: The infectious agent should be stored in leak-proof containers that are appropriately labelled Footnote 23.


REGULATORY INFORMATION: The import, transport, and use of pathogens in Canada is regulated under many regulatory bodies, including the Public Health Agency of Canada, Health Canada, Canadian Food Inspection Agency, Environment Canada, and Transport Canada. Users are responsible for ensuring they are compliant with all relevant acts, regulations, guidelines, and standards.

UPDATED: September 2011

PREPARED BY: Pathogen Regulation Directorate, Public Health Agency of Canada.

Although the information, opinions and recommendations contained in this Pathogen Safety Data Sheet are compiled from sources believed to be reliable, we accept no responsibility for the accuracy, sufficiency, or reliability or for any loss or injury resulting from the use of the information. Newly discovered hazards are frequent and this information may not be completely up to date.

Copyright ©

Public Health Agency of Canada, 2011



Report a problem or mistake on this page
Please select all that apply:

Thank you for your help!

You will not receive a reply. For enquiries, contact us.

Date modified: