Weekly Coronavirus Update: Tuesday, September 29, 2020
Happy Tuesday, everyone. Here is the latest Coronavirus research from the past week, including information on young people, reinfection, a genetic connection to some severe cases, the airborne nature of the virus, treatment, early symptoms, Covid-sniffing dogs, and a world update.
1) My first two points in this week’s post will deal with the topic of kids and Covid-19. First, looking at the immune response of children versus adults, a peer-reviewed study published in the journal Science Translational Medicine compared 65 children and youth (aged 24 years and younger) to 60 adults over the age of 25. Children had higher levels of two specific immune system molecules (interleukin 17A, which helps mobilize immune system response during early infection, and interferon gamma, which combats viral replication) than adults. These two molecules are part of the innate immune system that responds soon after infection. The study found that the higher the age of the patient, the lower their levels of IL-17A and INF-g. This is the first study to compare the immune responses of children and adults, so as always more research is needed, but these findings provide preliminary evidence of why children seem to fare so much better with the virus. You can read the full study here: https://stm.sciencemag.org/content/early/2020/09/21/scitranslmed.abd5487
2) A new peer-reviewed study published in JAMA Pediatrics showed that children and adolescents under the age of 20 were 44% less likely to be infected by Coronavirus than adults over the age of 20. The researchers conducted a meta-analysis of the findings from 32 different studies to determine this. The researchers were not able to conclude whether infected children transmit the virus at lower rates, though. As this was a meta-analysis, this study was also not able to make any claims regarding WHY children are less susceptible to infection. You can read the full study here: https://jamanetwork.com/journals/jamapediatrics/fullarticle/2771181
3) With regard to the potential for reinfection after someone has had Coronavirus, new peer-reviewed research published in the journal Clinical Infectious Disease described the cases of two healthcare workers in India, a 25-year-old male and 28-year-old female, who were infected with the virus a second time. Both workers initially tested positive in May, but were asymptomatic. They tested negative 8 days and 10 days after their diagnoses, respectively. In late August and early September, both individuals tested positive for Coronavirus again. Both were asymptomatic the second time, but had higher viral loads than during their first infection. Of note, genetic analysis of the virus showed that both hospital workers were infected with a DIFFERENT strain of the virus the second time, proving that they truly were cases of reinfection and not leftover virus particles from the first infection. The authors stated that asymptomatic cases of reinfection are likely under-reported. You can read the full study here: https://academic.oup.com/cid/advance-article/doi/10.1093/cid/ciaa1451/5910388
4) Two different peer-reviewed studies published in the journal Science found that 14% of severe cases of Covid-19 were linked to genetic flaws in which patients had rogue antibodies (known as autoantibodies) that attacked their own type-I interferon activity, which are immune-signalling chemicals necessary for fighting viruses. Patients found to have these genetic flaws were from all over the world, all different ages, and different ethnicities. Interestingly, 94% of patients with interferon-attacking antibodies were male, which could help to explain why men are at higher risk of severe cases of Covid-19. One of the studies also noted that the interferon-attacking antibodies are found in almost all patients with autoimmune polyendocrinopathy syndrome type I and in women with systemic lupus. You can read a summary of the two studies here: https://www.sciencemag.org/news/2020/09/hidden-immune-weakness-found-14-gravely-ill-covid-19-patients
The first study can be read in full here: https://science.sciencemag.org/content/early/2020/09/25/science.abd4570
The second study can be read in full here: https://science.sciencemag.org/content/early/2020/09/23/science.abd4585
5) The airborne transmission of the virus is a hot topic lately, and the consensus of experts is that the virus is indeed spread through aerosols (smaller droplets that can be carried through the air and travel greater distances than the larger droplets from sneezes or coughs, which tend to fall to the floor quickly). The big question now is how long do these aerosols stay in the air? Scientific results published in the New England Journal of Medicine estimated that infectious Sars-CoV-2 (Covid-19) particles could still be detected after three hours. Researchers at the University of Bristol in the UK have developed an apparatus that will allow them to control for temperature, humidity, and UV light to better understand how environmental conditions affect the length of time the virus remains infectious while suspended in air. The study began yesterday, so we should soon have news about their results. Stay tuned. I will be sure to post updates when they’re available. For now, you can read a news article about this research: https://www.theguardian.com/world/2020/sep/25/uk-scientists-begin-study-of-how-long-covid-can-survive-in-the-air?CMP=Share_iOSApp_Other
6) In treatment news, a study that has yet to undergo peer-review (important disclaimer) found that a nasal spray designed to stop Coronavirus from replicating was effective in ferrets. The drug in the nasal spray interacts with cells in the nasal cavity to activate a person’s (or in this case, a ferret’s) immune system. Three groups of six ferrets were given varying doses of the nasal spray, with one additional group receiving a placebo. All ferrets were exposed to Coronavirus. Five days after exposure, the amount of viral RNA (genetic materials of the virus) was 96% less in those ferrets who received the nasal spray than those in the placebo group. Next, the drug needs to be tested in humans to determine whether it is safe and effective. If so, it could be used as a preventative measure and would hopefully reduce the level of transmission of the virus. You can read the full study here: https://www.biorxiv.org/content/10.1101/2020.09.25.309914v1.full.pdf
7) I often report on the findings of the COVID Symptom Study in the UK, which relies on millions of users logging their health information daily, along with any results of Coronavirus tests. A new report by the researchers of this study highlights the early symptoms that are commonly experienced in the first seven days of infection, when people are most infectious. Fatigue and headaches are the most common for all age groups, with 82% of people testing positive experiencing fatigue and 72% experiencing headaches. Only 9% of adults between the ages of 18–65 who tested positive did NOT experience one of these symptoms. Still, the researchers noted that headaches and fatigue can also be common in a lot of people who do not have Coronavirus, so they reported the other top three symptoms in various age groups. For those under age 18, the other three most common symptoms are fever (48%), sore throat (40%), and cough (38%). In 18–65 year olds, they were loss of smell (55%), sore throat (49%), and cough (49%). For those over age 65, they were fever (41%), cough (41%), and loss of appetite (40%). You can read the report here: https://covid.joinzoe.com/post/early-covid-signs
8) In a previous update I reported on a study that showed dogs were able to detect Covid-19 in humans via smell. New research from The University of Helsinki confirmed this, and the researchers have started a pilot project at the Helsinki-Vantaa Airport. Airline passengers provide a skin swipe and a Covid-trained dog sniffs the sample to determine whether the passenger has Covid-19. The pilot project costs significantly less than administering Coronavirus tests, and in the university’s preliminary tests the dogs were nearly 100% accurate in detecting cases, even detecting cases days before people developed symptoms of the virus. You can read the university’s press release about this project here: https://www.helsinki.fi/en/news/life-science-news/the-sharp-noses-of-covid-dogs-are-utilized-at-the-helsinki-vantaa-airport and a news article from The Guardian about it here: https://www.theguardian.com/world/2020/sep/24/close-to-100-accuracy-airport-enlists-sniffer-dogs-to-test-for-covid-19
9) Finally, your world update. The US is currently experiencing a 15% increase in overall cases from two weeks ago (the seven-day average number of new daily cases is 42,275), and the top five states where the virus is growing fastest include North Dakota, South Dakota, Wisconsin, Utah, and Iowa. At US colleges and universities there have now been over 130,000 Coronavirus cases at over 1,300 institutions.
On Friday the UK had its highest daily number of new cases ever since the virus has been in existence with 6,873. Universities in the UK are also being affected by the virus, with approximately 40 universities experiencing cases on their campuses. Some universities have put students into lockdown in their dorms, and some have moved to entirely online delivery.
Today the Netherlands announced its highest number of new daily cases with 3,011 and new safety measures have been introduced in the country to try to slow the spread, including wearing masks in shops and working from home if possible.
Globally, the number of deaths from Covid-19 has now passed 1 million, and World Health Organization officials say this number is likely an underestimate. About one-fifth of those are from the United States, which is currently at 204,000 deaths.
US information: https://www.nytimes.com/interactive/2020/us/coronavirus-us-cases.html?name=styln-coronavirus®ion=TOP_BANNER&block=storyline_menu_recirc&action=click&pgtype=LegacyCollection&impression_id=26a92c41-025c-11eb-b8a9-4d7c83b55e2a&variant=1_Show
UK case numbers: https://www.nytimes.com/interactive/2020/world/europe/united-kingdom-coronavirus-cases.html
UK universities: https://www.bbc.co.uk/news/uk-54322935
Netherlands: https://www.theguardian.com/world/live/2020/sep/29/coronavirus-live-news-rapid-covid-19-tests-to-be-rolled-out-worldwide-as-global-deaths-near-one-million?page=with:block-5f72faea8f0833e1e504240d#block-5f72faea8f0833e1e504240d
Global deaths: https://www.theguardian.com/world/2020/sep/29/global-coronavirus-deaths-pass-1m-with-no-sign-rate-slowing
That’s all for this week. Please keep social distancing, wear your mask, wash your hands, and close the toilet lid when you flush! I’ll be back with another update next Tuesday.
