There was so much to look forward to at the start of 2021 .
2021年初，有太多值得期待的事情。
The question was when , and not if , the health crisis that spread from a market in Wuhan , China would finally end .
問題不在於這場從中國武漢一個市場蔓延開來的衛生危機是否會結束，而在於何時結束。
Scientists developed two highly effective vaccines against the coronavirus in record time .
科學家們以創紀錄的速度研發出兩種針對冠狀病毒的高效疫苗。
Several more were waiting for approval .
還有幾種疫苗正在等待核准。
Governments in the United States , Europe , and Israel spent billions of dollars to start the biggest vaccination program in history .
美國、歐洲和以色列政府斥資數十億美元，啟動了史上規模最大的疫苗接種計畫。
China and Russia developed their own vaccines .
中國和俄羅斯研發了自己的疫苗。
And the UN-backed COVAX program purchased shots for developing and poor countries around the world .
此外，聯合國支持的「新冠疫苗全球取得機制」（COVAX）為世界各地的開發中國家和貧窮國家購買了疫苗。
In May , the U.S . and Western nations expanded the program to vaccinate young children .
5月，美國和西方國家擴大了疫苗接種計畫，開始為幼童接種。
Health officials issued new guidelines advising that fully vaccinated people no longer needed to wear face coverings in most situations .
衛生官員發布了新指引，稱完整接種疫苗的人在大多數情況下不再需要戴口罩。
The move was seen as the first step toward returning to normal conditions that existed before the pandemic .
此舉被視為恢復疫情前正常狀態的第一步。
But , scientists began to worry about the new versions of the coronavirus , called variants , soon after people started to receive the new vaccines .
但人們開始接種新疫苗後不久，科學家們就開始擔心冠狀病毒的新版本，也就是變異株。
It is normal for viruses to mutate , or change , over time .
病毒隨著時間推移發生突變或變化是很正常的。
A mutation that strengthens the virus helps it to spread by pushing out the weaker versions .
讓病毒變強的突變會把較弱的版本擠掉，從而幫助病毒傳播。
In February , the head of Britain's vaccination effort said the world faced around 4,000 variants of the virus that causes COVID-19 .
今年2月，英國疫苗接種工作負責人說，全世界面臨著大約4000種新冠病毒變異株。
But only some would raise concern .
但只有一部分會引起擔憂。
The two most worrisome variants now are Delta and Omicron .
目前最令人擔憂的兩種變異株是Delta和Omicron。
In the early days of the pandemic , many Asian countries appeared to have successfully fought the virus with strong measures .
疫情初期，許多亞洲國家似乎透過強而有力的措施成功抗擊了病毒。
By July , countries , including Japan , South Korea , Vietnam , and Thailand , were setting records for new cases and deaths .
到7月，日本、南韓、越南和泰國等國的新增病例和死亡人數都在創下紀錄。
The Delta variant appeared at a difficult time .
Delta變異株出現在一個困難時期。
When it started being reported , vaccination rates remained low in many countries .
當它開始被報告時，許多國家的疫苗接種率仍然很低。
And officials were moving quickly to reopen economies .
而且官員們正迅速推動重新開放經濟。
Then , infections of the Delta variant became widespread .
隨後，Delta變異株的感染大面積蔓延。
Governments , businesses , and schools reacted with more vaccination requirements and restrictions .
政府、企業和學校紛紛祭出更多的疫苗接種要求和限制措施來應對。
Some countries started to restrict international travelers and closed borders over concerns about the fast-spreading Omicron variant .
一些國家因擔心快速傳播的Omicron變異株，開始限制國際旅客入境並關閉邊境。
After another year of face coverings , restrictions , vaccines and variants , people are beginning to wonder whether this pandemic will ever go away .
又經歷了一年的口罩、限制措施、疫苗和變異株，人們開始懷疑這場大流行是否會有結束的一天。
The answer is yes and no .
答案是既會也不會。
Many scientists believe that the new coronavirus is here to stay .
許多科學家認為，新型冠狀病毒將長期存在。
In February , the science publication Nature reported the results of a study involving more than 100 scientists .
今年2月，科學期刊《自然》報導了一項有100多名科學家參與的研究結果。
Endemic means the virus will continue to exist in some areas for years to come .
地方性流行意味著病毒將在未來多年裡繼續在某些地區存在。
For example , Malaria is considered endemic to many warm , wet areas across countries in Asia , Africa , and South America .
例如，瘧疾被認為是亞洲、非洲和南美洲許多國家濕熱地區的地方病。
But it is not a problem in the United States or other Western nations .
但在美國或其他西方國家，它並不是問題。
The way to end a pandemic is to reach herd immunity .
結束大流行的方法是達到群體免疫。
Herd immunity is when many people in a community either have recovered from an infection or have been vaccinated .
群體免疫是指一個社區中的許多人要麼已從感染中康復，要麼已接種疫苗。
It does not mean everyone is protected from the virus .
這並不意味著每個人都能免受病毒侵害。
However , when herd immunity is reached , the virus can no longer spread easily , which helps protect those who are at risk .
然而，一旦達到群體免疫，病毒就無法再輕易傳播，這有助於保護高風險族群。
As nations joined together to fight the pandemic , health officials started to sound the alarm about another public health crisis : mental health .
在各國聯手抗擊疫情之際，衛生官員開始對另一場公共衛生危機——心理健康——發出警告。
There is hope , however .
不過，希望仍在。
Although health officials have already approved several treatments for COVID-19 , all of them must be injected by healthcare workers .
儘管衛生官員已經核准了幾種新冠治療藥物，但都必須由醫護人員注射。
But pills can be taken at home and are easier to send around the world .
但藥丸可以在家服用，而且更容易運往世界各地。
And I'm Mario Ritter , Jr .
我是小馬里奧·里特。