Some invisible agent — which would not be seen until the advent of electron microscopes a few decades later — was somehow transmitting disease. Effective antibiotics have been around for close to a century. Antiviral drugs have come along only in the last few decades, and only for a handful of serious threats. And they do not always help.
Timing is important. Antiviral drugs can lessen the duration of the flu, for example, but only if given early in the course of the disease. By the time a person develops severe symptoms, antiviral drugs are of little use, said Freeman, the Pitt physician.
That might also hold true for the new coronavirus, but more research is sorely needed, said Freeman, who studied the biology of a different coronavirus, SARS, while a Ph. Multiple teams of researchers also are at work on vaccines for the new coronavirus , teaching the human immune system to make its own medicine: antibodies.
The first stages of safety testing already are underway, but it will be at least a year before such a vaccine is approved for widespread use, experts predict. For now, that leaves supportive care. But as University of Pennsylvania medical historian David Barnes has found, nurses and doctors have been making that concept work for a long time.
At the Lazaretto Quarantine Station, a hospital on the Delaware River used to treat immigrants with yellow fever in the early 19th century, patients were more likely to survive the illness than were many in the general population, he said.
The regimen was straightforward: clean bedding, rest, adequate food and drink, and palliative medicines to ease the worst symptoms, said Barnes, who is writing a book on the topic. That may yet prove to be a challenge in the coronavirus outbreak.
Skip to content Share Icon. Facebook Logo. That worries people like Marc Lipsitch and Alison P. Galvani, two epidemiologists who write in a PLoS Medicine editorial today that creating these types of new infectious agents puts human life at risk.
They estimate that if 10 American laboratories ran these types of experiments for a decade, there would be a 20 percent chance that a lab worker would become infected with one of these new super-flus and potentially pass it on to others. In , a Russian scientist died after accidentally sticking herself with a needle contaminated with Ebola at a Siberian lab. And in March, the Galveston National Laboratory in Texas lost a vial containing Guanarito virus, which causes "bleeding under the skin, in internal organs or from body orifices like the mouth, eyes, or ears.
The medical world seems perpetually torn between the desire to eliminate horrific diseases entirely and the need to preserve them for future study. Thanks to vaccination, smallpox was eradicated in , but there are still two samples of it living in labs—one in the U.
There is no cure for smallpox, and it kills a third of its victims. With this outbreak, the coronavirus' so-called spike protein primarily fits "locks" that are present on lung cells, which is why COVID, the disease it causes, is mainly a respiratory illness. Once the invasion takes place, the cell in essence is transformed into a factory that churns out hundreds and hundreds of copies of the virus, based on instructions encoded in its genetic material — RNA, or ribonucleic acid, in the case of the coronavirus.
The human body has evolved defense systems to protect against these kinds of infections. First, cells have a built-in alarm system to detect viral invaders.
The presence of an intruder triggers what's known as an innate immune response, which can involve the host cell releasing a protein that tries to interfere with the virus' replication or can involve the immune system trying to shut down the compromised cells. The work of these reinforcements to try to defeat the virus is typically what causes the symptoms of a viral infection — in other words, it's at this point when a person may come down with a fever and start to feel sick.
But viruses are sneaky, Glaunsinger said, and they are often able to fly under the radar and cause a lot of damage before any alarms are triggered and any reinforcements are called in. By the time an immune response kicks in, it's often too late. When the immune system is finally triggered, it can also kick into overdrive, causing what's called a cytokine storm, which is thought to be the root of some of the most severe coronavirus cases.
Adam Lauring, an associate professor of microbiology and immunology at the University of Michigan in Ann Arbor. Download the NBC News app for full coverage and alerts about the coronavirus outbreak. The extreme immune response can worsen pneumonia and cause severe inflammation in the sickest patients, Gatherer said. The ability of a virus to evade detection is another reason it's difficult to treat with medications. Antiviral drugs are also challenging to develop, because they need to work very specifically to combat certain viruses.
That's different from antibiotics, which can treat a variety of bacterial infections.
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