Table 3. Secondary transmission of HIV in the first 6 years following screening program implementation.
| HIV testing frequency | ||||
| Current practice | One-time | Every 5 years | Annually | |
| National population | ||||
| Prevalence 0.29%, Incidence 0.032/100PY, background testing 3.2% per year | ||||
| Number of secondary cases (per 100,000) | 6.92 | 6.75 | 6.65 | 6.19 |
| Incremental HIV cases averteda (per 100,000) | – | 0.17 | 0.10 | 0.46 |
| % incremental decrease | – | 2.5 | 1.5 | 6.9 |
| High prevalence district | ||||
| Prevalence 0.8%, Incidence 0.088/100PY, background testing 3.3% per year | ||||
| Number of secondary cases (per 100,000) | 6.99 | 6.82 | 6.72 | 6.26 |
| Incremental HIV cases averteda (per 100,000) | – | 0.17 | 0.10 | 0.46 |
| % incremental decrease | – | 2.4 | 1.5 | 6.8 |
| High-risk group | ||||
| Prevalence 5.0%, Incidence 0.552/100PY, background testing 50% per year | ||||
| Number of secondary cases (per 100,000) | 6.84 | 6.84 | 6.81 | 6.70 |
| Incremental HIV cases averteda (per 100,000) | – | 0.0 | 0.03 | 0.11 |
| % incremental decrease | – | 0.0 | 0.4 | 1.6 |
PY – person-years.
Transmission coefficient ranges from 0.16/100 PY to 9.03/100 PY depending on HIV RNA level [45].
a
Incremental HIV cases averted relative to those averted with the next less frequent HIV testing strategy.