Survival of meningococci outside of the host: implications for acquisition

Abstract

Meningococci are regarded as being unlikely to survive outside of their human host although this has possibly been more assumed than demonstrated. Seven strains of meningococci were tested for their ability to survive on glass or plastic while retaining expression of their capsule and important outer membrane proteins. A known number of colony-forming units of each strain were dried onto glass and onto plastic and tested for viability over time. Survival on glass was significantly better than on plastic (P<0.0001). Isolates of the New Zealand epidemic strain, B:4:P1.7-2,4 survived better on glass than all other strains tested. Recovered isolates still expressed their capsules and outer membrane proteins. These findings raise the question of whether meningococci can be transferred from person to person via fomites contaminated with oropharyngeal secretions containing meningococci.

Fig. 1

Percentage survival on glass of all seven meningococcal strains by sampling time. □, NZ97/122;, Cu00162; ■, NZ03/280;, NZ98/254; , H44/76-SL; , NZ04/198; , NZ03/225.

Fig. 2

Comparison of survival times for group B meningococcal strains with PorA type (P1.7-2,4) (■) or an alternative Por A (□).

Fig. 3

Percentage of survival over time of group B meningococcal strains on plastic. □, NZ03/280;, NZ97/122; ■, NZ98/254;, Cu00162.

Fig. 4

The percentage survival of all strains on glass (■) compared with plastic (□).