Efetividade das vacinas em gestantes com síndrome respiratória aguda grave pela Covid-19 no Brasil

Abstract

COVID-19 is an acute respiratory illness caused by severe acute respiratory syndrome coronavirus 2. As a result of its rapid spread in several countries, in March 2020 the World Health Organization (WHO) declared it a pandemic. The first risk groups were composed of the elderly and people who had other underlying health conditions. Initially, only high-risk pregnant women were considered a risk group, however, as the pandemic progressed, developing countries showed a considerable increase in mortality and severe maternal morbidity, which led the WHO to consider all pregnant and puerperal women as group of risk. Thus, this retrospective cohort study evaluated the effectiveness of vaccines in pregnant women diagnosed with SARS by COVID-19 in Brazil. Data collection was carried out from January to December 2021, using the SIVEP-Flu database. A total of 237,780 women with severe COVID-19 were included, 232,625 were non-pregnant and 5,155 were pregnant. When evaluating the vaccination coverage against COVID-19, it was observed that among non-pregnant women, 89,273 (38.38%) were immunized and among pregnant women, 987 (19.2%). Among the number of completed cases, that is, those with a cure or death outcome, 80,890 died. Of these, 80,276 (34.51%) were non-pregnant and 614 (12%) were pregnant. For the initial survival analysis, hospitalized patients with severe COVID-19 were divided into two groups, non-pregnant and pregnant women, using the variables age, comorbidities, immunosuppression and vaccination. The risk ratio (HR) for COVID-19 was more impactful among pregnant women who had immunosuppression (HR 1.39; 95% CI 1.33 – 1.45; p = < 0.000), who had one or more comorbidities ( HR 1.24; 95% CI 1.22 – 1.26; p = < 0.000) and related to age (HR 1.02; 95% CI 1.02 – 1.03; p = < 0.000). Among the groups that presented lower RH are the unvaccinated (HR 0.92; CI 95% 0.85 – 1.01; p = 0.055) and the vaccinated (HR 0.79; CI 95% 0.78 – 0. 81; p = < 0.000). Vaccinated women had better survival than non-vaccinated ones, and among the latter, pregnant women had the best results. Cox multivariate regression analysis was repeated for all variables, excluding pregnant women aged 60 years or older (Table 6). The results maintained risk ratios with the same order of impact on the analyzed variables: immunosuppression (HR 1.53; CI 95% 1.44 – 1.63; p = < 0.000), comorbidities (HR 1.48; CI 95% 1.44 – 1.52; p = < 0.000), age (HR 1.01; 95% CI 1.00 – 1.16; p = < 0.000), unvaccinated (HR 0.82; 95% CI 0 .75 – 0.89; p = < 0.000) and vaccinated (HR 0.34; 95% CI 0.26 – 0.45; p = < 0.000). The results showed the same order of impact of the risk ratio for the survival of the analyzed patients, including those aged 60 years or older. However, all analyzed variables showed slower progression to death. In conclusion, our study indicates that: (i) immunization for COVID-19 increases survival in pregnant and non-pregnant women with severe COVID-19 in Brazil. (ii) immunization reduced the number of deaths in hospitalized pregnant women with severe COVID-19 in Brazil. However, vaccination did not protect non-pregnant women with comorbidities or immunosuppressed.