Covid

Covid

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Opinion: These Covid-19 symptoms raise new questions
Opinion: These Covid-19 symptoms raise new questions
With an elevated risk of heart disease, stroke and blood clots as a possible long-term effect of Covid-19, perhaps the Veterans Affairs researchers will do something that almost a million American deaths has not: frighten a broad swath of the vaccine-hesitant into rolling up their sleeves and taking the shots, writes Kent Sepkowitz
·cnn.com·
Opinion: These Covid-19 symptoms raise new questions
COVID risk assessment
COVID risk assessment
I hesitated posting this at all, because I am profoundly uninterested in hearing guesses framed as facts from all of the armchair epidemiologists out there, and this is catnip for them... But here's how I've been seeing things these last few months. Maybe you have too. My goal is to not catch COVID at all. CDC tells me that my goal should instead be just "don't fill the hospitals past 100%", ...
·jwz.org·
COVID risk assessment
Understanding Risk
Understanding Risk
We’re coming to the end of a wave. The CDC is changing guidance. Schools are removing mask mandates. More than 253 million people have at least one dose of the vaccine. A lot is changing, and today looks very different from March 2020. Together, many of us are reflecting on our own risk tolerance and possibly recalibrating.
·yourlocalepidemiologist.substack.com·
Understanding Risk
New CDC (mask) guidance: My two cents
New CDC (mask) guidance: My two cents
This afternoon the CDC provided on- and off-ramps for public health mitigation measures (like masks) going forward. The CDC made it clear that the sole purpose of the new framework is to prevent severe disease and, thus, not overwhelm hospital systems at the local level.
·yourlocalepidemiologist.substack.com·
New CDC (mask) guidance: My two cents
'Natural immunity' to COVID has its limits
'Natural immunity' to COVID has its limits
This article was originally posted in the Montreal Gazette Quite a few people have been talking recently about natural immunity. They have heard that once you get infected with COVID-19, you have antibodies that should protect you against future infections. This is true, up to a point. But what is often neglected is that with infections, much like with vaccinations, immunity wanes with time and new variants compromise some of the protection we previously had. Early on there was strong that people who had recovered from COVID-19 would be protected, and early evidence seemed to suggest that that would be the case. An analysis from Italy early in 2021 found that reinfections over the first year of the pandemic were rare. However, the authors themselves cautioned that their data was collected before the new variants started to circulate widely, and it was unknown how well natural immunity would hold up against new strains. Unfortunately, new variants are increasingly different from the original virus and antibodies in your bloodstream are less likely to be able to stick to the virus and therefore help your immune system fight off the infection. The progressively increasing risk of reinfection was made clear by a recent study from Qatar. It found that the protection offered by a previous infection was very high—at 90 and 92 percent against the Alpha and Delta variants, respectively—but dropped to 56 percent with Omicron. So, while having had a prior infection did offer some protection, that protection drops as the virus continues to mutate. What is often lost in the discussion is the fact that infection and vaccination are not either/or propositions. An individual with a previous COVID-19 infection can and should get vaccinated. Even as early as last year before the emergence of the Omicron variant, CDC data from the United States found that people who had recovered from COVID-19 but remained unvaccinated had more than twice the odds of being reinfected compared to someone who was fully vaccinated. In the last week, two new studies in the New England of Journal Medicine have bolstered that point and suggest that there is considerable benefit to getting vaccinated even after recovery from COVID-19. In the first study, researchers in Israel reviewed the medical records of individuals post-COVID infection and found that those who received at least one vaccine dose had a five-fold lower risk of reinfection. Too few subjects in their study sample received two doses to draw meaningful conclusions about the benefits of a second dose in this population, though. The second study, among U.K. healthcare workers, was a more broad-ranging study that looked at different vaccines, dosing schedules and the effectiveness over time in both uninfected and previously infected individuals. However, when they looked at individuals previously infected with COVID-19, those who got two vaccine doses were more than 90 percent less likely to get reinfected than unvaccinated individuals even several months after their second doses. When discussing different studies, it is important to acknowledge that they are often done in different countries, at different points of time, with different circulating variants, different vaccine protocols and using different methodologies. However, all these studies consistently indicate that an added benefit to getting vaccinated even if you previously caught COVID-19. Ideally, you want to wait three months post-infection to get vaccinated, as current recommendations suggest. If you get vaccinated too soon after getting sick, it is likely that your body is still producing high levels of antibodies and the vaccine will likely not provide much of an immune boost. It is the same rationale that underlies spacing out vaccine doses. Many people likely believe that prior infection will protect them forever, but unfortunately, it will not. The vaccines provide a critical immune boost to people who have recovered. That is, after all, what vaccines were designed to do. @DrLabos
·mcgill.ca·
'Natural immunity' to COVID has its limits
The Masked Kids Are Alright
The Masked Kids Are Alright
It is easy to raise the specter of science to scare people. Talk about a new vaccine technology messing with your DNA and you’ve conjured up instant anxiety. It is an especially potent technique when the target of the sciency boogeyman is a child. Children are frequently at the center of moral panics, from video games to heavy metal music, from alleged Satanic ritual abuse to reactionary views on gender expression. When it comes to masking children during the COVID-19 pandemic—especially when said masking is mandated in schools—a perfect storm is whipped up. The specter of science can once again be summoned to scare the bejesus out of parents. “Will my child suffocate?” parents start asking. “Will this lead to permanent developmental issues?” Sciency-looking findings can be shared to bolster fears. Brushing aside the politically motivated fearmongering on the part of bad actors, we are left with reassuring logic, encouraging data, and leftover questions that have no easy answers and no ethical way of being adequately probed. Real-world science can be messy. Claims of physical harm A common claim about this issue is the fear that children will suffocate, either from not getting enough oxygen or from a build-up of carbon dioxide (CO2). A scientific review published in 2011 (and thus before COVID) mentions the fact that “a child’s respiratory system is not merely a miniaturization of an adult’s:” children do not breathe as deeply as adults and they take more breaths per minute. Hence, a mask might be fine on an adult but might, in theory, impact a child’s breathing because of these differences. I cannot overstate how much heavy lifting the phrase “in theory” does here. Luckily, we don’t have to play armchair worrier here: we have data. Public Health Ontario published a synthesis of the evidence we have on mask-wearing in children less than a month ago, and the data they highlight is reassuring. Six studies looked to see if wearing a mask impaired a child’s respiratory function, and there was no objective evidence of this, only reports of subjective complaints. Some kids (like some adults) didn’t like wearing a mask and felt like they couldn’t breathe as well, but when this was measured, there was nothing wrong. There’s even a study that tested three-layer surgical masks in hockey players ages 9-14 and had them simulate a hockey game both on and off the ice, and this study found no effect on their heart rate or in how much oxygen their bodies were getting. Earloop medical masks and reusable face coverings tend to be loose enough that breathing through them is not a problem. Oxygen and CO2 are small enough molecules that they do not get trapped in the mask: they pass through easily. That study that showed masks were poisoning kids with CO2? It was retracted by its journal, JAMA Pediatrics. The reason? Fundamental concerns about how the study was done, including the misuse of a measuring device. It is bound to become a “zombie paper,” though, a whisper haunting Facebook groups: “There’s a study showing masks poison our children, you know?” A bad paper can travel halfway around the world while its retraction is putting on its shoes. Even though a child’s respiratory system is not perfectly comparable to an adult’s, we know from adults that masks are not death traps. Surgeons and dentists don’t drop dead from wearing them day in, day out. When the Russian team’s COVID testing results weren’t made available, players on the Canadian women’s hockey team to the Beijing 2022 Winter Olympics agreed to play wearing N95 respirators, which provide a tighter seal and thus more resistance than a medical mask. They won 6-1. As of this writing, none has died of oxygen deficiency or CO2 toxicity. The other claims of physical harm include the idea that wearing a mask will weaken your child’s immune system. There is no evidence of that. Masks are said to increase illness and deaths, which is a complete canard. In studies of schools with and without a mask mandate, those with the mandate have fewer cases of COVID-19. This benefit cannot solely be attributed to the masks, as other measures are usually in place, but the masks are certainly not making the situation worse. Some have argued that masks are bathing kids’ mouths in microbes, a bugbear that’s meant to trigger disgust, but that is just not true. Again: doctors, nurses, dentists. If microbes are found on the outside surface of a mask, it is not evidence of harm to the child; it is evidence of the mask doing its job. Soiled gloves in the operating room do not imply the surgical staff got infected. It means the protection was necessary. As for the claim that children wearing a mask will start breathing through their mouth, which will elongate their faces in what has been dubbed “adenoid face” or “long face syndrome,” there is a microscopic grain of truth here. According to the evidence-based medical resource UpToDate, there is limited evidence for chronic mouth-breathing being associated with any effect on the face and mouth during development. Importantly, doctors do not know how long one would have to breathe through one’s mouth for this to have a relevant effect on the shape of one’s face. Let’s also remember that kids are not being asked to wear masks 24/7. Their faces are uncovered while sleeping, at home, outside, and while eating. The odds of a temporary mandate for masking in schools influencing a child’s face are, in my opinion, very, very low. There is thus little to no merit to the claims of physical harm. What about psychological harm? Claims of psychological harm Here, the evidence is not as clear-cut, though it is important to remember that, unlike underwear, masks are not expected to be worn every day for the rest of a child’s life. Some parents fear that young children will have difficulty recognizing their masked teachers and school staff. This can be mitigated in two ways: being consistent with regards to glasses and hairstyle, for example, and adopting a recognizable, personalized mask or a characteristic item of clothing. Then there is the issue of emotions. When trying to understand how someone feels, we rely in part on the expression on their face. With half of their face hidden behind a mask, it becomes harder. Some worry that children who are learning to identify emotional information from looking at people’s faces might fall behind. Studies have been done getting children to match a masked or unmasked face to an emotion, and the results are mixed. A couple of studies show the mask adds difficulty; one shows no dramatic impairment, similar to wearing sunglasses; and another one, while using a dark circle that only hides the mouth and leaves more of the face uncovered than a mask, showed no difference for children under the age of 9. It is important to remember, once again, that children still get to practice this skill at home and outdoors, where masks are not used. Moreover, we do have real-world examples that predate the pandemic. In some cultures, wearing a mask or partially veiling the face is common. As Professor Eva Chen, a developmental psychologist at the Hong Kong University of Science and Technology, told The New York Times in 2020, there is no evidence that children growing up in those cultures are any worse at recognizing faces or emotions. This anxiety, when voiced by certain doctors, seems to come mainly from American and European professionals, as opposed to Asian doctors in whose culture the wearing of a mask to protect against illness or air pollution is more common. And as Canadian psychiatrist Tyler Black told TVOntario, we don’t seem to panic about the wearing of sunglasses around children, even though they also obscure our faces. Many experts interviewed in the media brought up this key concept of adaptability. Children are plastic. Their development is not easily stunted. Annoyances and tolerance With the more dramatic claims out of the way, here’s a lightning round on the annoyances kids report while having to wear a mask and how tolerant they are of having it covering their nose and mouth. Masks can irritate the skin, true, and four studies report as much, even though they were small and lacked a control group, but a bit of facial moisturizer can help and switching to a different brand of mask may resolve the issue. Masks can fog up glasses. I personally share this frustration. Washing the lenses with soapy water will do the trick but might distort the view. Taping the mask down on the nose with a Band-Aid or a piece of waterproof tape available in the first aid section of drugstores works really well. It prevents moist air exhaled from the mouth from reaching and condensing on the lenses, and it leaves the mask in perfect condition when removed. Masks can make it harder to be heard or to hear the teacher, especially if windows are open or air cleaners are turned on in the classroom to improve air quality. This is perhaps the thorniest issue here. Teachers could wear masks with a clear plastic insert in front of the mouth to facilitate lip-reading, but those are reported to fog up very easily and might block sound more than medical masks. Kids can still develop verbal skills at home, watching television, and through remote learning, when teachers don’t have to wear a mask, but in class, muffled speech is an issue. Teachers are often advised to speak louder, enunciate, and gesticulate to better convey emotions, which is an added burden to an already exhausted profession. Anecdotally, some parents say their kids don’t tolerate wearing a mask. While this may be true, scientific data is encouraging. In most studies of children during COVID-19, over 70% of children wore their masks in the classroom when it was mandated. There is data showing similar adherence by children during SARS, H1N1, and even in studies where children were asked to wear a gas mask or a respirator for upwards of six hours (data summarized here). Some children are un
·mcgill.ca·
The Masked Kids Are Alright
Why Covid-19 vaccines are a freaking miracle
Why Covid-19 vaccines are a freaking miracle
The pandemic has been catastrophic. But consider something that may have escaped you: You have witnessed — and you are a beneficiary of — a freaking miracle.
·statnews.com·
Why Covid-19 vaccines are a freaking miracle
Measles Makes Your Immune System Forget Its Protections Against Past Illness
Measles Makes Your Immune System Forget Its Protections Against Past Illness
Historically, contracting the measles has been linked to subsequent illness (and possibly death) from other causes. In the past few years, scientists have discovered why this is: measles causes "immune amnesia"
·kottke.org·
Measles Makes Your Immune System Forget Its Protections Against Past Illness
Long-term cardiovascular outcomes of COVID-19
Long-term cardiovascular outcomes of COVID-19
Nature Medicine - Individuals with COVID-19 are at increased long-term risk for a wide range of cardiovascular disorders, even for individuals who were not hospitalized during the acute phase of...
·nature.com·
Long-term cardiovascular outcomes of COVID-19
Riding the waves: A framework for the future of SARS-CoV-2
Riding the waves: A framework for the future of SARS-CoV-2
Si quiere leer la versión en español, pulse aquí. One thing is consistent after the peak of every wave: A highly charged debate on how we move forward as individuals, as a community, as a nation, and as a globe. For example, right now we have one side suggesting to drop masks from here on out and another side that says keep mask mandates.
·yourlocalepidemiologist.substack.com·
Riding the waves: A framework for the future of SARS-CoV-2
Two underdog but game changing vaccines: NVX-CoV2373 (Novavax) and CORBEVAX
Two underdog but game changing vaccines: NVX-CoV2373 (Novavax) and CORBEVAX
One way (maybe the only way) we’re going to get out of this pandemic is to vaccinate a large portion of the global population. To the WHO, this means reaching 70% of the population by mid-2022, which is ~3 billion unvaccinated people with 6-9 billion doses before another variant of concern.
·yourlocalepidemiologist.substack.com·
Two underdog but game changing vaccines: NVX-CoV2373 (Novavax) and CORBEVAX
What the Omicron wave is revealing about human immunity
What the Omicron wave is revealing about human immunity
Immunologists have raced to work out how to protect against multiple variants of SARS-CoV-2. Their research has yielded a wealth of insights and a few surprises.
·nature.com·
What the Omicron wave is revealing about human immunity
Infectious viral load in unvaccinated and vaccinated patients infected with SARS-CoV-2 WT, Delta and Omicron | Request PDF
Infectious viral load in unvaccinated and vaccinated patients infected with SARS-CoV-2 WT, Delta and Omicron | Request PDF
Request PDF | Infectious viral load in unvaccinated and vaccinated patients infected with SARS-CoV-2 WT, Delta and Omicron | Viral load (VL) is one determinant of secondary transmission of SARS-CoV-2. Emergence of variants of concerns (VOC) Alpha and Delta was ascribed,... | Find, read and cite all the research you need on ResearchGate
·researchgate.net·
Infectious viral load in unvaccinated and vaccinated patients infected with SARS-CoV-2 WT, Delta and Omicron | Request PDF
COVID-19 vaccines and decreased transmission of SARS-CoV-2
COVID-19 vaccines and decreased transmission of SARS-CoV-2
A massive COVID-19 vaccination campaign is underway worldwide. Epidemiological data from studies indicate excellent efficacy and safety profile for COVID-19 vaccines. However, there are few data from studies on the effect of decreasing the probability ...
·ncbi.nlm.nih.gov·
COVID-19 vaccines and decreased transmission of SARS-CoV-2
What now? How pandemics end
What now? How pandemics end
It looks like Omicron has peaked in the United States and in many countries across the globe. Case patterns may uptick with the introduction of subvariant lineage, BA.2, but with a little luck we will largely be on our descent. And I can’t help but notice my inbox piled with great questions:
·yourlocalepidemiologist.substack.com·
What now? How pandemics end
What Will Pandemic Life Be Like in a Month?
What Will Pandemic Life Be Like in a Month?
Bob Wachter is the chair of the Department of Medicine at the USCF medical center and last week he posted a pair of threads about what the Covid rates might look like in a month and how we might behave if that comes to p
·kottke.org·
What Will Pandemic Life Be Like in a Month?