蚊子会传播新冠病毒吗?专家是这么说的……
进入夏季,讨厌的吸血蚊虫又开始多起来,有人担心被蚊子叮咬会有感染新冠病毒的风险,对此专家表示,新冠病毒几乎不可能通过蚊子来传播。
Mosquito season is upon us, and considering that these bloodsuckers are known to transmit diseases, people are concerned: Do mosquitoes carry the coronavirus? And if so, can they transmit it to humans and infect a person with COVID-19?
又到蚊子季了,想到这些吸血昆虫会传播疾病,人们感到担忧:蚊子会携带新冠病毒吗?如果可以,它们会不会把新冠病毒传播给人类,让人感染上新冠肺炎?
Short answer: it's unlikely. Official guidance from the World Health Organization (WHO) says there’s no information or evidence to suggest that the new coronavirus could be transmitted through mosquito bites.
简单来说,答案是:不太可能。世界卫生组织的官方指南称,没有信息或证据显示,新冠病毒会通过蚊虫叮咬来传播。
For starters, the coronavirus is a respiratory virus, and the main mode of transmission are viral droplets released into the air when an infected person coughs or sneezes. For a mosquito to become infected with a virus, it must be present in the blood the mosquito feeds on.
首先,新冠病毒是一种呼吸道病毒,这种病毒的主要传播模式是感染者咳嗽或打喷嚏时把带有病毒的飞沫释放到空气中。一只蚊子要感染上新冠病毒,病毒就必须进入蚊子吸食的血液中。
"SARS-CoV2 (the virus that causes COVID-19) is a respiratory virus that is almost exclusively contained within the lungs and respiratory tract of infected people, and rarely gets into the blood,” Emily Gallichotte, PhD, a postdoctoral researcher in the department of microbiology, immunology, and pathology at Colorado State University, tells Health.
科罗拉多州立大学微生物学、免疫学与病理学系的博士后研究员艾米丽·盖丽洛特博士告诉健康网说:“新冠病毒是一种呼吸道病毒,几乎完全存在于感染者的肺部和呼吸道中,很少会进入血液中。”
Plus, for a virus to pass to a person through a mosquito or other kind of insect bite—such as a tick bite—the virus must be able to replicate inside the mosquito or tick. Neither the new coronavirus nor any other type of coronavirus has been shown to do that.
而且,病毒要通过蚊子或其他昆虫叮咬(比如蜱虫叮咬)传播给另一个人,病毒必须能在蚊虫或蜱虫体内复制。事实表明,新冠病毒和其他任何一种冠状病毒都无法做到这点。
"It’s quite a complex process,” former US Navy entomologist Joseph M. Conlon, who has extensive worldwide experience in mosquito control and is technical advisor to the American Mosquito Control Association (AMCA), tells Health. “First of all, the mosquito would have to pick up the requisite amount of virus during its bite. The virus must then not only survive the digestive process, but replicate within the mosquito and pass through the gut wall to the coelom (main body cavity) of the mosquito. From there it must make its way to the salivary glands and be expressed by the mosquito as part of its salivary secretions.”
曾在美国海军服役的昆虫学家约瑟夫·M·康伦告诉健康网说:“这是一个相当复杂的过程。” 康伦在蚊虫控制方面有着丰富的全球经验,也是美国控蚊协会的技术顾问。“首先,蚊子必须在叮咬过程中吸收足够的病毒。病毒不仅必须在消化过程中存活下来,还必须在蚊子体内进行复制,并通过肠壁进入体腔。之后还必须到达唾液腺,并作为唾液分泌物释放出来。”
Furthermore, mosquitoes are very genetically different from humans. “This makes it challenging for viruses to have the ability to infect both of us,” says Gallichotte. “We have different receptors on the surface of cells and different replication machinery inside our cells.”
此外,蚊子的基因和人类大不相同。盖丽洛特说:“这让病毒难以既感染人类又感染蚊虫。我们的细胞表面有不同的感受器,细胞内部的复制机制也不同。”
Relatively few human viruses have the ability to infect both humans and mosquitoes. “The vast majority of human viruses (such as influenza, HIV, and herpes) have been infecting humans for a very very long time, and even though many of these end up in our blood, they are still unable to infect mosquitoes,” says Gallichotte. “Conversely, there are many mosquito viruses that are unable to infect humans, or any mammals. There are no known coronaviruses that can infect mosquitoes.”
能够既感染人类又感染蚊虫的人类病毒相对较少。盖丽洛特说:“绝大多数人类病毒(比如流感、艾滋病和疱疹)很长很长的时间以来一直在感染人类,尽管其中的许多病毒最终都进入了人类的血液,但仍无法感染蚊虫。反之,许多蚊虫病毒也无法感染人类或其他任何哺乳动物。目前已知的冠状病毒还没有能够感染蚊子的。”
Viruses that can be spread to humans by mosquitoes include West Nile virus, the virus that causes dengue fever, and chikungunya virus, which all circulate in the blood of infected people. “West Nile virus is able to infect a mosquito to the point where the virus load is abundant in the salivary glands,” Melissa Doyle, scientific program manager at the San Gabriel Valley Mosquito and Vector Control District (SGVMVCD), tells Health. “When the mosquito bites a person, the virus is able to travel from the salivary glands into the human body.”
能够通过蚊子传播给人类的病毒包括引发登革热的西尼罗河病毒和基孔肯亚病毒,这些病毒都在感染者的血液中循环。圣盖博山谷蚊及病媒控制区的科学项目经理梅丽莎·道尔告诉健康网说:“西尼罗河病毒能够感染蚊子,并在蚊子的唾液腺里大量聚积。当蚊子叮咬人时,病毒能通过唾液腺传播给人体。”
So it’s pretty clear that COVID-19 is the last thing you should be worrying about if a mosquito has been feasting on your leg. Keep swatting them away, though. “Due to the heavy focus on COVID-19, many people may forget that disease threats may already be buzzing right outside their window.” SGVMVCD Public Information Officer Levy Sun tells Health.
因此很明显,如果蚊子叮了你的腿,你完全不用担心会感染新冠病毒。但是还是应该把它们拍走。圣盖博山谷蚊及病媒控制区公共信息官莱维·孙告诉健康网说:“由于现在非常关注新冠病毒,许多人也许忘记了窗外嗡嗡响的疾病威胁。”
Conlon points out that mosquitoes can factor into the severity of COVID-19, meaning it’s crucial to maintain robust measures to reduce their numbers. “Studies have shown that factors contributing to potentially serious or fatal outcomes attendant to COVID-19 infection involve underlying medical issues, such as neurologic conditions that weaken the ability to cough or an already stressed immune system due to concurrent infection by mosquito-borne viruses,” he says.
康伦指出,蚊子会加重新冠肺炎的病情,这意味着持续采取强硬措施来降低蚊虫数量是至关重要的。他说:“研究显示,感染新冠病毒后引发致命结果的因素包括潜在的医疗问题,比如减弱咳嗽能力的神经系统疾病,或蚊虫携带病毒导致的并发感染给免疫系统造成的负担。”
Mosquitoes or no mosquitoes, it’s still crucial to keep following healthy coronavirus protocol to protect yourself and others from COVID-19. Clean your hands frequently, practice social distancing, stay home if you’re sick, and avoid close contact with anyone who is coughing and sneezing.
无论有没有蚊子,坚持遵守卫生防疫要求来保护自己和他人免受新冠病毒感染仍然是至关重要的。勤洗手,保持社交距离,病了就在家休息,避免和任何咳嗽或打喷嚏的人密切接触。