Given the high rate of asymptomatic infection, all pregnant women should be tested for gonorrhea infection. However, communal baths, towels or fabric, rectal thermometers and caregivers hands have been implicated as means of transmission in the pediatric setting. Kissing has also been implicated as a theoretical means of transmission in the gay male population, based on a newer study.Traditionally, the bacterium was thought to move attached to spermatozoa, but this hypothesis did not explain female to male transmission of the disease. A recent study suggests that rather than "surf" on wiggling sperm, N. gonorrhoeae bacteria use pili to anchor onto proteins in the sperm and move through coital liquid. Infection
For N. gonorrhoeae, the first step after successful transmission is adherence to the epithelial cells found at the mucosal site that is infected. The bacterium relies on type IV pili that attach and retract, pulling N. gonorrhoeae toward the epithelial membrane where its surface proteins, such as opacity proteins, can interact directly. After adherence, N. gonorrhoeae replicates itself and forms microcolonies. While colonizing, N. gonorrhoeae has the potential to transcytose across the epithelial barrier and work its way in to the bloodstream. During growth and colonization, N. gonorrhoeae stimulates the release of cytokines and chemokines from host immune cells that are pro-inflammatory. These pro-inflammatory molecules result in the recruitment of macrophages and neutrophils. These phagocytic cells typically take in foreign pathogens and destroy them, but N. gonorrhoeae has evolved many mechanisms that allow it to survive within these immune cells and thwart the attempts at elimination.
The pili mediate adherence, movement, and DNA exchange. The Opa proteins interact with the immune system, as do the porins. Lipooligosaccharide (LOS) is an endotoxin that provokes an immune response. All are antigenic and all exhibit antigenic variation (see below). The pili exhibit the most variation. The pili, Opa proteins, porins, and even the LOS have mechanisms to inhibit the immune response, making asymptomatic infection possible.Dynamic polymeric protein filaments called type IV pili allow N. gonorrhoeae to adhere to and move along surfaces. To enter the host the bacteria uses the pili to adhere to and penetrate mucosal surfaces. The pili are a necessary virulence factor for N. gonorrhoeae; without them, the bacterium is unable to cause infection. To move, individual bacteria use their pili like a grappling hook: first, they are extended from the cell surface and attach to a substrate. Subsequent pilus retraction drags the cell forward. The resulting movement is referred to as twitching motility. N. gonorrhoeae is able to pull 100,000 times its own weight, and the pili used to do so are amongst the strongest biological motors known to date, exerting one nanonewton. The PilF and PilT ATPase proteins are responsible for powering the extension and retraction of the type IV pilus, respectively. The adhesive functions of the gonococcal pilus play a role in microcolony aggregation and biofilm formation. Surface proteins called Opa proteins can be used to bind to receptors on immune cells and prevent an immune response.