Table 2.
Vaccine effectiveness studies in Latin America and the Caribbean during the COVID‐19 pandemic
| Study | Country | Vaccine | Doses and schedule | Participants | Effectiveness (95% CI) | Other conclusions |
|---|---|---|---|---|---|---|
| González et al. [140] | Argentina | Gam‐COVID‐Vac (Sputnik V) | One dose, first component | Individuals aged 60–79 years (n = 40,387) | 78.6% (74.8–81.7) for preventing laboratory‐confirmed infections | Prevention of hospitalisation (87.6%; 95% CI: 74.8–81.7), and death (84.8%; 95% CI: 75.0–90.7) |
| Hitchings et al. [141] | Brazil | AZD1222 (Oxford‐AstraZeneca) | Two doses (0 and 21 days) | Adults aged 60 years or older (n = 137,744) | 77.9% (69.2–84.2) for prevention of symptomatic SARS‐CoV‐2 infection | Prevention of hospitalisation (87.6%; 95% CI: 78.2–92.9), of ICU admission (89.9%; 95% CI: 70.9–96.5), invasive mechanical ventilation (96.5%; 95% CI 81.7–99.3), and death (93.6%; 95% CI 81.9–97.7) in the fully immunised group. |
| Alencar et al. [142] | Brazil | CoronaVac (Sinovac Life Sciences) and AZD1222 (Oxford‐AstraZeneca) | Two doses | Elderly people aged 75 years or older (n = 313,328) | Protection ratio of 132.67 (109.88–160.18) against COVID‐19‐related death with two doses. | Protection ratio of 19.31 (18.20–20.48) against COVID‐19‐related death with one dose. |
| Hitchings et al. [143] | Brazil | CoronaVac (Sinovac Life Sciences) |
Two doses (0 and 14 days) (n = 53,176) |
Healthcare workers, aged 18 years or older | 37.1% (53.3–74.2) for prevention of symptomatic SARS‐CoV‐2 infection | At least one dose was associated with an effectiveness of 49.4% (95% CI 13.2–71.9) for prevention of symptomatic SARS‐Cov‐2 infection |
| Ranzani et al. [144] | Brazil | CoronaVac (Sinovac Life Sciences) | Two doses (0 and 14 days) | Individuals aged > 70 years (n = 43,774) | 46.8% (38.7–53.8) for preventing symptomatic COVID‐19 | Effectiveness against hospital admissions was 55.5% (95% CI 46.5–62.9) and against death was 61.2% (95% CI 48.9–70.5) |
| Jara et al. [145] | Chile | CoronaVac (Sinovac Life Sciences) | Two doses (0 and 14 days) | Participants 16 years of age or older (n = 10,187,720) | 65.9% (65.2–66.6) for the prevention of COVID‐19 (n = 4,173,574) | Prevention of hospitalisation (87.5%; 95% CI: 86.7–88.2), of ICU admission (90.3%; 95% CI: 89.1–91.4) and death (86.3%; 95% CI 84.5–87.9) in the fully immunised group. |
| Murillo‐Zamora et al. [146] | Mexico | BNT162b2 (Pfizer‐BioNTech) | Two doses (0 and 21 days) | Healthcare workers aged 18 years and above with laboratory‐confirmed COVID‐19 (n = 312) | Vaccine effectiveness was 100% against severe illness after one or two doses of the vaccine | ‐ |
| Silvia‐Valencia et al. [147] | Peru | BBIPB‐CorV (Sinopharm) | Two doses (0 and 21 days) | Healthcare workers aged 18 years and above (n = 606,772) | 50.4% (49.0–52.0) for prevention of SARS‐CoV‐2 infection after two doses | 94.0% (91.0–96.0) for prevention of COVID‐19 related‐death after two doses |