Table 1. Key characteristics of the HIV models.
| Goals | Optima HIV | HIV Synthesis | EMOD | |
|---|---|---|---|---|
| Structure | Compartment model for population 15–49 with 11 risk groups | Compartment model with age, sex and risk group disaggregation | Individual-based stochastic model | Individual-based stochastic model |
| Calibration | Epidemic parameters adjusted to fit surveillance and survey data | Epidemic parameters adjusted to fit surveillance and survey data | Epidemic parameters varied to generate a large number of scenarios from which those matching specified characteristics can be selected | Epidemic and behavioral parameters varied to create simulations which are matched to surveillance and survey data. 250 parameter sets are selected to represent plausible fits. |
| Sexual and injecting behavior | Regular, casual and commercial sex; men having sex with men; people who inject drugs | Regular, casual and commercial sex; men having sex with men; people who inject drugs | Short- and long-term condomless sexual partners | Marital, informal, transitory and commercial partnerships |
| HIV acquisition determinants | Number and types of partners, acts per partner, condom use, male circumcision status, PrEP use, STI prevalence, viral suppression through ART, stage of infection | Number of partners, acts per partner, condom use, male circumcision status, PrEP use, viral suppression through ART, stage of infection, type of sex | Type of condomless sex partnership, PrEP use, circumcision and (sexually active) community viral load | Number and types of partners, acts per partner, condom use, male circumcision status, PrEP use, STI prevalence, viral suppression through ART, stage of infection |
| MTCT | CD4 count of mother or type of prophylaxis, retention, duration of breastfeeding | CD4 count of mother or type of prophylaxis, duration of breastfeeding | Viral load of mother at birth | CD4 count of mother or type of prophylaxis, retention on prophylaxis |
| Settings | India, Kenya, Malawi, Nigeria, South Africa, Zimbabwe | 38 countries* | Applied to a range of settings that encompass most epidemics in sub-Saharan Africa | South Africa |
• Argentina, Armenia, Belarus, Brazil, Bulgaria, Cambodia, Colombia, Democratic Republic of the Congo, Eswatini, Ethiopia, Haiti, India, Iran, Kazakhstan, Kenya, Kyrgyzstan, Macedonia (Former Yugoslav Republic), Malawi, Mexico, Moldova, Mozambique, Nepal, Nigeria, Papua New Guinea, Peru, Russian Federation, Senegal, South Africa, Sudan, Tajikistan, Tanzania, Thailand, Togo, Uganda, Ukraine, Uzbekistan, Vietnam, and Zimbabwe.