当地时间3月30日，世卫组织举行新冠肺炎例行发布会，世卫组织总干事谭德塞表示，现有研究表明，最有可能出现的情况是新冠病毒将继续进化，但随着人体免疫力因疫苗接种或感染病毒而增强，新冠病毒导致疾病的严重性会随着时间推移而降低。

According to WHODirector-GeneralTedros Adhanom Ghebreyesus,the most likely scenario is that the virus continues to evolve, but the severity of disease it causes reduces over time as immunity increases due to vaccination and infection.

世卫组织总干事谭德塞资料图

但如果人的免疫力减弱，病例数量和死亡人数可能会出现周期性高峰，这种情况下弱势群体需要定期接种新冠疫苗加强针。

Periodic spikes in cases and deaths may occur as immunity wanes, which may require periodic boosting for vulnerable populations.

谭德塞指出，最好的情况是出现不太严重的变异株，从而不需要接种加强针或调整疫苗成分。而最坏的情况是出现一种致病性更强且具有高度传染性的变异株，在这种情况下，此前接种疫苗或感染病毒所带来的保护力将迅速减弱。

In the best-case scenario, we may see less severe variants emerge, and boosters or new formulations of vaccines won’tbe necessary.

Inthe worst-case scenario, a more virulent and highly transmissible variant emerges. Against this new threat, people’s protection against severe disease and death, either from prior vaccination or infection, will wane rapidly.

文章来源：中国日报双语新闻