Science and the Coronavirus: Medical treatments, clinical trials, and what makes the coronavirus so contagious
From time to time, we'll be bringing you a roundup of the latest coronavirus news as pertains to science, medical treatments, medical trials, and studies from the scientific community. Here's the first edition.
SOLIDARITY, a global megatrial of four promising coronavirus treatments, launched by WHO
The World Health Organization (WHO) has launched a global trial called SOLIDARITY to test if existing medicines - a drug combo already used against HIV; a malaria treatment first tested during World War II; a new antiviral whose promise against Ebola fizzled last year - can treat infections with the new coronavirus for the dangerous respiratory disease. The study could include thousands of patients in dozens of countries, and is designed to be as simple as possible so that even hospitals that are overwhelmed with an onslaught of patients with COVID-19 can participate.
Upto 15% of patients with COVID-19 are suffering from severe disease and the ongoing pandemic has brought existing healthcare systems to their knees, particularly in Italy, which is struggling. The fear is that as cases go up around the world, what is happening to the Italian healthcare system can and will happen in other countries. Coming up with compounds from scratch will take years to develop and test, so researchers and public health agencies are looking to repurpose drugs already approved for other diseases, and known to be largely safe.
Although scientists have suggested dozens of existing compounds for testing, WHO is focusing on what it says are the four most promising therapies: an experimental antiviral compound called remdesivir; the malaria medications chloroquine and hydroxychloroquine; a combination of two HIV drugs, lopinavir and ritonavir; and that same combination plus interferon-beta, an immune system messenger that can help cripple viruses. Some data on their use in COVID-19 patients have already emerged—the HIV combo failed in a small study in China—but WHO believes a large trial with a greater variety of patients is warranted.
The design is not double-blind, the gold standard in medical research, so there could be placebo effects from patients knowing they received a candidate drug. But WHO says it had to balance scientific rigour against speed. The idea for SOLIDARITY came up less than 2 weeks ago, Henao Restrepo says, and the agency hopes to have supporting documentation and data management centers set up next week. “We are doing this in record time,” she says.
China documented the high number of asymptomatic transmissions that make the coronavirus so contagious
The novel coronavirus that originated in Wuhan, China, towards the end of 2019 quickly spread to all Chinese provinces, and, as of 1st March 2020, to 58 other countries. Although efforts to contain the virus are ongoing, there are unfortunately many uncertainties regarding pathogen transmissibility and virulence.
For example, not everyone displays severe symptoms of the disease; some people are asymptomatic, and others only develop mild symptoms that go away on their own. This means that these people are unaware that they have contracted the virus and that they are contagious, thereby continuing with their daily lives and infecting many other people as they do so. This is particularly problematic with regards to this virus.
To assess the full epidemic potential of SARS-CoV2 (the novel coronavirus), Chinese scientists used a model-inference framework to estimate the contagiousness and proportion of undocumented infections in China during the weeks before and after the shutdown of travel in and out of Wuhan. In this mathematical model, they divided infections into two classes: (i) documented infected individuals with symptoms severe enough to be confirmed, i.e., observed infections; and (ii) undocumented infected individuals. These two cases of infection have different rates of transmission.
Overall, their findings indicated that a large proportion of COVID-19 infections were undocumented prior to the implementation of travel restrictions and other heightened control measures in China on 23 January, and that a large proportion of the total force of infection was mediated through these undocumented infections. This high proportion of undocumented infections, many of whom were likely not severely symptomatic, appears to have facilitated the rapid spread of the virus throughout China.
Why it's important to act now
Tomas Pueyo illustrates in this article - with charts, data, and models with plenty of sources - the deadly nature of the coronavirus, and the unavoidable fact that this pandemic is coming to your city, your town, wherever you may live.
This article should be suggested reading for every politician, community leader, or business leader the world over because they have the power and the responsibility to prevent this pandemic from reaching further heights, and saving countless lives that will otherwise be affected adversely by the coronavirus.
The timeline of events in Hubei shows you what authorities knew as opposed to what was really happening. When they thought there were 100 new cases every day, the actual number was 1500, but they didn't know that. When the number of new cases every day rose to 400, authorities shut down the city, but the actual number at the time was 2500. 15 more cities in Hubei followed suit, but it's clear from the graph that cases stopped exploding the moment Wuhan shut down. The official number of cases were still rising because more and more people started presenting with symptoms and going to hospitals, but *new* cases stopped.
The rest of China took immediate drastic measures and followed suit, and there is a graph that shows the results of that. Thanks to the measures by the Chinese government, the spread of the coronavirus was halted. South Korea, Italy, and Iran did not learn from the Chinese model, even though they had a full month to do so. They started the same exponential growth of Hubei and passed every other Chinese region before the end of February.
Aerosol and surface stability of HCoV-19 (SARS-CoV-2) compared to SARS-CoV-1
This is a comprehensive study of the amount of time the coronavirus lingers on surfaces and in the air. By linking to a number of studies and articles, this study attempts to illustrate the life span of the coronavirus. MedRxiv is a repository of early-stage scientific papers that have not yet been peer reviewed.
Basically, it is established that the coronavirus appears able to linger in the air for up to three hours and on plastic and stainless steel surfaces for two to three days, according to laboratory tests run by a team of federal and academic scientists in the US.
It’s unclear whether the virus would behave the same way in the real world. Since it began circulating in December, it has infected more than 124,000 people worldwide — making it officially a pandemic, according to the World Health Organization.
Person-to-person contact is believed to be the main way that the new virus is transmitted, according to the CDC, though transmission through contaminated objects and surfaces “may be possible.” The agency acknowledged that “novel coronavirus may remain viable for hours to days on surfaces made from a variety of materials.”
China reports new progress in drug, therapies against Covid-19
Favipiravir is an influenza antiviral drug which was approved for clinical use in Japan in 2014. According to Zhang Xinmin, director of the China National Center for Biotechnology Development under the Ministry of Science and Technology, the drug has shown no obvious adverse reactions in the clinical trial and has shown good clinical efficacy against the Covid-19 (coronavirus) outbreak.
More than 80 patients have participated in the clinical trial in The Third People's Hospital of Shenzhen, south China's Guangdong Province, including 35 patients taking Favipiravir and 45 patients in a control group.
Results showed that patients receiving Favipiravir treatment turned negative for the virus in a shorter time compared with patients in the control group.