冠狀病毒能被溫暖的天氣擊潰嗎?

冠狀病毒能被溫暖的天氣擊潰嗎?

There's a seasonality to many viruses. Flu and cold viruses tend to peak in winter months, then die down with warmer weather.

許多病毒都有季節(jié)性。流感和感冒病毒往往在冬季達到高峰，然后隨著天氣變暖而逐漸消失。

Will the newly identified coronavirus and the disease it causes — COVID-19 — follow a similar pattern?

新發(fā)現的冠狀病毒和它引起的疾病COVID-19會遵循類似的模式嗎?

Before that question can be answer, let's consider how seasons and temperature influence the spread of viruses.

在回答這個問題之前，讓我們考慮一下季節(jié)和溫度如何影響病毒的傳播。

"Coronaviruses tend to be associated with winter because of how they're spread," explains Elizabeth McGraw, who directs the Center for Infectious Disease Dynamics at Pennsylvania State University. For one thing, in winter months, people may cluster together more indoors, increasing the number of folks at risk of becoming infection by someone who's contagious.

“由于冠狀病毒的傳播性，所以往往與冬季有關，”賓夕法尼亞州立大學傳染病動力學中心主任伊麗莎白·麥格勞解釋說。首先，在冬季，人們可能會更多地聚集在室內，增加了被有傳染性的人感染的風險。

In addition, there's the matter of transmission. Viruses spread through respiratory droplets that are released when an infected person coughs or sneezes. And the droplets are more likely to spread under certain conditions.

此外，還有傳播的問題。病毒通過被感染者咳嗽或打噴嚏時釋放的飛沫傳播。液滴在一定條件下更容易擴散。

"What we know is that they're [the droplets] are better at staying afloat when the air is cold and dry, " says McGraw. "When the air is humid and warm, [the droplets] fall to the ground more quickly, and it makes transmission harder."

“我們所知道的是，當空氣寒冷干燥時，它們(水滴)更能保持漂浮，”麥格勞說。“當空氣潮濕而溫暖時，(水滴)降落到地面的速度更快，傳播也更困難。”

Not every coronavirus hews to the same rules. For instance, the one that causes Middle East Respiratory Syndrome (MERS) has not shown the capacity to spread easily from person to person, says Amesh Adalja, an infectious disease physician and a senior scholar at the Johns Hopkins Center for Health Security: "It doesn't have that seasonality because it's really an animal to human virus and not something that that you see causing disease in a seasonal pattern."

并不是每一種冠狀病毒都遵守同樣的規(guī)則。例如，引起中東呼吸綜合征(MERS)的一種病毒并沒有顯示出在人與人之間容易傳播的能力，傳染病內科醫(yī)生、約翰·霍普金斯健康安全中心高級學者阿梅什·阿達爾賈說：“它沒有季節(jié)性，因為它實際上是一種動物傳人的病毒，而不是你認為的季節(jié)性致病病毒。”

But he says COVID-19 seems more akin to the seasonal cold. And up to a third of common colds are caused by coronaviruses.

但他表示，COVID-19似乎更類似于季節(jié)性寒冷。高達三分之一的普通感冒是由冠狀病毒引起的。

"We've seen, basically, explosive spread inside China of person-to-person transmission, so — in that sense — it really is behaving like a common-cold causing coronavirus," says Adalja.

阿達爾賈說:“我們已經看到，在中國國內，基本上是人傳人的爆發(fā)性傳播，所以，從這個意義上說，它確實表現得像導致普通感冒的冠狀病毒。”

For that reason, he says, "I do think seasonality will play a role. As this outbreak unfolds and we approach spring and summer, I do think we will see some tapering off of cases."

出于這個原因，他說，“我確實認為季節(jié)性將發(fā)揮作用。隨著疫情的展開，我們將接近春季和夏季，我確實認為我們將看到病例有所減少。”

So as China and the rest of the Northern Hemisphere head into spring, the virus could begin to peter out or plateau. But the southern half of the globe is headed into fall and winter "so we may see this [virus] have increased transmission" in parts of the southern hemisphere, says Adalja — for example, in Australia. That's similar to what happens with the flu each year.

因此，隨著中國和北半球其他國家邁入春季，病毒可能會開始逐漸消失或停滯不前。但是，阿達爾賈說，地球的南半部正在進入秋季和冬季，“所以我們可能會看到這種[病毒]在南半球的部分地區(qū)增加了傳播”，例如在澳大利亞。這與每年流感的情況相似。

"It's not unreasonable to make the assumption" that cases will die down come spring, Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, told NPR. "We hope when the weather gets warmer it will diminish a bit," he says.

美國國家過敏和傳染病研究所所長安東尼·福奇博士在接受美國國家公共電臺采訪時表示，“認為明年春天過敏病例會減少并不是沒有道理的”。他說:“我們希望當天氣變暖時，它會減少一點。”

But he sounds a cautionary note: "However, we don't know that about this [new] coronavirus. We don't have [a] backlog of history."

但他發(fā)出了警告:“然而，我們對這種(新的)冠狀病毒并不了解。我們沒有積壓的歷史。”

Dr. Nancy Messionnier of the Centers for Disease Control and Prevention sounds a similar note when it comes to predicting a slowdown of cases with warmer weather. "I think it's premature to assume that," she said during a call with reporters on Wednesday. "We haven't been through even a single year with this pathogen."

當談到天氣變暖時，疾病控制和預防中心的南希·梅西奧尼耶博士聽起來也有類似的說法。她在周三與記者的電話會議中表示：“我認為現在斷定這一點還為時過早。”“我們甚至一年都沒有感染過這種病原體。”

Given the uncertainty, public health officials say they must plan for the unexpected and for the possibility that the outbreak drags on regardless of the weather.

鑒于不確定性，公共衛(wèi)生官員表示，他們必須為意想不到的情況做好計劃，并考慮到無論天氣如何，疫情都可能會持續(xù)下去。