False-negative results from coronavirus tests are becoming an increasing concern, say doctors trying to diagnose patients and get a grip on the outbreak, as a surprising number of people show up with obvious symptoms only to be told by the tests that they don’t have the disease.
While still more research is necessary to determine the true prevalence of such false-negative results, experts agree that the problem is significant. False negatives not only impede the diagnosis of disease in individual patients and an accurate understanding of the extent of its proliferation, but also risk patients who think they aren't ill further spreading the virus.
Some doctors described situations in which patients show up with clear symptoms such as a cough and fever, test negative, and then test positive later on. It’s a particular issue in New York, where the disease has likely infected far more than the 174,000 people confirmed through limited testing. At Jacobi Medical Center in the Bronx, doctor Jeremy Sperling says so-called false-negative tests are now a frequent occurrence in the emergency room. “If a patient presents with classic Covid symptoms, but tests negative, they’ve still got Covid,” said Sperling, who is the chair of emergency medicine at the hospital. “There is just nothing else it could be in New York City in 2020.” Concerns about false negatives arise from a mix of factors: quickly created tests from dozens of labs and manufacturers that haven't been extensively vetted by federal health regulators; a shortage of supplies and material for the tests that may impact results, long incubation times for the infection, and the challenge of getting an adequate sample from a patient. Most tests rely on a nasal swab that penetrates deep into the pharynx, the mucous membrane behind the nose and mouth. Even for a trained health worker, it can be difficult: It’s an invasive procedure that often causes patients to squirm. With a shortage of staff to conduct such widespread testing, in many cases people not typically trained to do so are collecting samples.
Some doctors described situations in which patients show up with clear symptoms such as a cough and fever, test negative, and then test positive later on.
False Negatives Raise Doctors' Doubts About Coronavirus Tests A surprising number of patients have obvious symptoms but still test negative, say doctors
By Kristen V Brown
April 11, 2020, 1:45 PM CDT
False-negative results from coronavirus tests are becoming an increasing concern, say doctors trying to diagnose patients and get a grip on the outbreak, as a surprising number of people show up with obvious symptoms only to be told by the tests that they don’t have the disease.
While still more research is necessary to determine the true prevalence of such false-negative results, experts agree that the problem is significant. False negatives not only impede the diagnosis of disease in individual patients and an accurate understanding of the extent of its proliferation, but also risk patients who think they aren't ill further spreading the virus.
Some doctors described situations in which patients show up with clear symptoms such as a cough and fever, test negative, and then test positive later on. It’s a particular issue in New York, where the disease has likely infected far more than the 174,000 people confirmed through limited testing. At Jacobi Medical Center in the Bronx, doctor Jeremy Sperling says so-called false-negative tests are now a frequent occurrence in the emergency room.
“If a patient presents with classic Covid symptoms, but tests negative, they’ve still got Covid,” said Sperling, who is the chair of emergency medicine at the hospital. “There is just nothing else it could be in New York City in 2020.”
Concerns about false negatives arise from a mix of factors: quickly created tests from dozens of labs and manufacturers that haven't been extensively vetted by federal health regulators; a shortage of supplies and material for the tests that may impact results, long incubation times for the infection, and the challenge of getting an adequate sample from a patient.
Most tests rely on a nasal swab that penetrates deep into the pharynx, the mucous membrane behind the nose and mouth. Even for a trained health worker, it can be difficult: It’s an invasive procedure that often causes patients to squirm. With a shortage of staff to conduct such widespread testing, in many cases people not typically trained to do so are collecting samples.
这是nature上德国新冠病人研究文章。
下图是核酸检测病毒量的图，虚线是检测限，低于虚线检不出。黄色是鼻咽取样，橙色是痰液，灰色是粪便。
说中国试剂盒30%准确度的是文盲脑残，媒体上说过很多遍了，是鼻咽部病毒量问题，不是试剂盒问题。
对，多上美国微博推特上看看，各种怪事情shit show简直多的让人下巴掉不完。
联邦和州抢PPE各种物资，麻省好容易搞倒的一线医院急需物资被FEMA截了，好给床铺吹牛用。不是一次了，很多州都碰上了，气得要死。
医院赶人超快，25岁小伙儿刚拔管儿就被赶回家，结果肾衰重回急诊室，很快就死了。
PCR检测本身都是高灵敏度高准确度，各国都一样。问题不在试剂盒，在取样，还有人员训练问题，角度不对，深度不够都可能取不到。所以核酸检测不是非常可靠。
Drive through test放走很多假阴性回家了。
本来就检测能力不够，更不会同一人多次测试了。
"美国微博推特"????
你暴露了。。。。
美国微博在哪儿？我也想看看
有点幽默感好不好，够迟钝的
早期的病例看ct有啥用
这个问题3月份版上就讨论过了，说这在医生里面本来就是常识，并不是这次新冠才知道的。我之前见过的视频里面就有好几个医生合力帮一个病人翻身的镜头，因为病人身上全是各种管子，不是那么容易翻身
美国几百年来闭关锁国固步自封，一直拒绝学习世界的先进科技文化。美国人生活好全靠印美元。
当然有， 有些人都不知道自己肺部感染了， 照CT才看出来
轻症看ct能有用？
明显他的意思是推特是美国的微博。
有用，多看几次早点癌症，给国家省钱，真不知道粉毛嘎吹ct是个啥脑回路
就是輕症測不出，中症以後才可以，就是病毒量的問題。早就是輕症不給測，科學道理就是這個。
看那个采访，气的我，唉，他们不知道跟中国医生咨询一下么？草菅人命
colormdy 发表于 2020-04-19 12:55
你家估计没啥在医院当医生的亲戚
华人上还有一堆人坚持美国就是先进，准确率９５％以上。说实话这次美国的自大愚昧真是令人震惊。
你真别出来现眼了。
叹为观止的不学无术