1/Suspected #SARSCoV2 reinfection in Peru🇵🇪: symptomatic 42yr old tested positive in June, but did not develop pneumonia (Row A👇). She improved, symptoms resolved. Then in October, she presented w/symptoms again, tested positive, this time had lung lesions w/pneumonia (Row B)🧵
2/case highlights there are far more reinfections than confirmed. Bar to establish reinfection is high: requires genetic sequencing of viruses to rule out single continuing infection but only small # of samples are sequenced/stored for future purposes like confirming reinfection.
3/For instance, at the GISAID international database of SARS-CoV-2 genetic sequences, there are only 385 virus🧬sequences from Peru, but the country has reported about 1 Million cases, so only 0.04% of cases have been sequenced.
4/"Expanding knowledge about reinfection would help the population maintain control measures, thus reduce the proportion of the population reinfected and the possibility of presenting complications of the disease in its second episode." sciencedirect.com/science/articl…
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📌1/CDC Report on Vietnam's🇻🇳Incredible Tracing/Quarantine Program: after outbreak in major Hanoi Hospital, entire 7,664-persons staff quarantined. Contact tracing in the community resulted in an additional 52,239 people being quarantined. After 3 weeks, outbreak was contained🧵
2/They didn't just quarantine close contacts of infected, but all hospital visitors & their close contacts (F2s) were provided quarantine support: room and board. Contacts of F2s (F3s) & Contacts of F3s (F4s) were even asked to self-isolate: wwwnc.cdc.gov/eid/article/27…
3/Aggressive tracing/quarantine in Vietnam isn't unique to this outbreak. As @findingsen writes, once case is identified, all contacts in prior week are identified and quarantined. Those individuals' contacts are identified and asked to self-isolate. globalasia.org/v15no3/cover/v…:
1/📌SARS-CoV-2 in aerosols: from dispersion in air, to inhalation and disease: (a) while large drops (green) are ballistically and fall, smaller ones (red) can remain buoyant; (b) Droplets evaporate to form aerosols, reducing to just biopolymers and virus particles🧵
2/Larger aerosols deposit in upper throat, nose, & tracheobronchial region of the lung. Medium-sized aerosols mostly deposit in small airways further down. The really small aerosols <1 μm can penetrate all the way to the alveoli - the basic units for gas exchange.
3/In contrast to other mode of transmission where virus hits nasal cavity and then finds its way into lungs, aerosols can directly reach alveolar region and attack alveolar cells that produce Pulmonary Surfactant. PS is needed to lower surface tension & prevent alveoli collapse
1/📌COVID-19 neurological challenges: while respiratory problems receive most attention, nearly 10-35% survivors suffer disabling, persistent neurological symptoms. Patients w/altered mental health hospitalized 3X times longer; 2/3 unable to manage daily activities at discharge🧵
2/Underlying causes are complex. Low oxygen; metabolic irregularities. Inflammatory response in the brain—activation of microglia & cytotoxic T cells—and other signs of neuropathy have also been observed.
3/Loss of smell/taste: 40-60% of patients develop loss of smell; ~90% have alteration of smell. Many recover sense of smell, others have more severe cases, possibly permanent loss of smell. Virus invades cells in vicinity of olfactory nerve; unclear if it directly invades nerve
1/The #AstraZeneca vaccine is a version of an adenovirus (common cold virus) that delivers instructions to our cells to make the Spike protein of the coronavirus. That way our immune system is "trained" so when it encounters #SARSCoV2, it can mount an efficient response🧵
2/#SARSCoV2 is covered w/Spike proteins that help the virus grab human cells. To make the vaccine, researchers first isolated the gene that is responsible for making the Spike protein. They 'snipped' it from the rest of the genetic material of the coronavirus.
3/They then needed a delivery vehicle to get the Spike gene into our cells. So they took an adenovirus that normally infects chimpanzees, and genetically altered it so it can no longer replicate or cause disease. They then added the Spike gene to the adenovirus vector.
1. CDC: Postponing travel & staying home is the best way to protect yourself and others, especially if those you're visiting are at increased risk of getting very sick from COVID-19, like older adults & those with medical conditions. But there are plenty of other risks too🧵
2. Other factors that make your visit especially high risk are if cases in your community or the ones you're visiting are high. You can check that in CDC’s COVID Data Tracker here: bit.ly/392Dx0A. Many areas also have travel restrictions: bit.ly/3lQsUS1
3. You can also find out if hospitals in your community or your destination are overwhelmed with COVID-19 patients. That could make it a challenge to get the help you or others may need if you get sick. You can get that info by checking state & local public health dep. websites.
📍CDC Guidance Update: Masks don't just reduce the amount of virus we release🗣️, masks also reduce the amount of virus we inhale😷. Here's a thread on some published🔬studies on the effectiveness of masks in cutting down #SARSCoV2 transmission🧵
1. In a study of 124 Beijing households with confirmed cases of SARS-CoV-2 infection, mask use by the index patient and family contacts BEFORE the index patient developed symptoms reduced secondary transmission within the households by 79%. pubmed.ncbi.nlm.nih.gov/32467353/
2. Two hair stylists who were COVID-19 positive spent at least 15 min with 139 clients. 67 clients who agreed to be tested were all negative and none of the other clients are known to be infected. Everyone was wearing masks 😷.
Report: bit.ly/2ZrjGD0