Gonorrhea
Gonorrhea (Neisseria gonorrhoeae) follows the SEIS pattern with immediate infectiousness (no latent period) and tracks drug resistance.
Class: sti.Gonorrhea | Alias: 'ng' | Base class: SEIS
States and transitions
┌─────────────┐
│ Susceptible │◄──────────────────────────────────────┐
└──────┬──────┘ │
│ infection (immediately infectious) │
│ │
├────────────────────┐ │
▼ ▼ │
┌─────────────┐ ┌──────────────┐ │
│Asymptomatic │ │ Symptomatic │ │
│ F: 65% │ │ F: 35% │ │
│ M: 35% │ │ M: 65% │ │
└──────┬──────┘ └──────┬───────┘ │
│ │ │
│ ├───────────┐ │
│ ▼ ▼ │
│ ┌───────────┐ ┌───────┐ │
│ │ Seeks care│ │ PID │ (F only) │
│ └───────────┘ └───────┘ │
│ │
└───────── natural clearance ──────────────────┘
F: ~8 mo M: ~6 mo
Parameters
Natural history
| Parameter |
Default |
Description |
dur_exp |
0 |
No latent period (immediately infectious) |
p_symp |
[0.35, 0.65] |
Probability of symptoms [F, M] |
dur_presymp |
F: [1 wk, 12 wk]; M: [0.25 wk, 1 wk] |
Time to symptom onset [mean, std] |
dur_asymp2clear |
F: [8 mo, 2 mo]; M: [6 mo, 3 mo] |
Duration of asymptomatic infection [mean, std] |
dur_symp2clear |
F: [9 mo, 2 mo]; M: [6 mo, 3 mo] |
Duration of symptomatic infection [mean, std] |
Care seeking
| Parameter |
Default |
Description |
p_symp_care |
[0.66, 0.83] |
Probability of seeking care if symptomatic [F, M] |
dur_symp2care |
F: [2 mo, 1 mo]; M: [1 wk, 2 wk] |
Time from symptoms to care seeking [mean, std] |
Complications
| Parameter |
Default |
Description |
p_pid |
0.0 |
Probability of pelvic inflammatory disease (females) |
dur_prepid |
lognorm(1.5 mo, 3 mo) |
Time to PID onset |
Transmission
| Parameter |
Default |
Description |
beta_m2f |
0.06 |
Per-act male-to-female transmission probability |
rel_beta_f2m |
0.5 |
Female-to-male transmission relative to male-to-female |
beta_m2c |
None |
Mother-to-child transmission probability |
beta_m2m |
None |
Male-to-male transmission probability |
eff_condom |
0.9 |
Condom efficacy |
init_prev |
0.01 |
Initial prevalence |