40% of people with coronavirus have no symptoms. Might they be the key to ending the pandemic?
https://www.chron.com/news/article/4...s-15469295.php
- One mind-blowing hypothesis - bolstered by a flurry of recent studies - is that a segment of the world's population may have partial protection thanks to "memory" T cells, the part of our immune system trained to recognize specific invaders. This could originate from cross-protection derived from standard childhood vaccinations. Or, as a paper published Tuesday in Science suggested, it could trace back to previous encounters with other coronaviruses, such as those that cause the common cold.

"This might potentially explain why some people seem to fend off the virus and may be less susceptible to becoming severely ill," National Institutes of Health Director Francis Collins remarked in a blog post this past week. On a population level, such findings, if validated, could be far-reaching.

Hans-Gustaf Ljunggren, a researcher at Sweden's Karolinska Institute, and others have suggested that public immunity to the coronavirus could be significantly higher than what has been suggested by studies. In communities in Barcelona, Boston, Wuhan and other major cities, the proportion of people estimated to have antibodies and therefore presumably be immune has mostly been in the single digits. But if others had partial protection from T cells, that would raise a community's immunity level much higher. This, Ljunggren said, would be "very good news from a public health perspective."

Some experts have gone so far as to speculate about whether some surprising recent trends in the epidemiology of the coronavirus - the drop in infection rates in Sweden where there have been no widespread lockdowns or mask requirements, or the high rates of infection in Mumbai's poor areas but little serious disease - might be due to preexisting immunity.

Others say it's far too early to draw such conclusions. Anthony Fauci, the United States' top infectious-disease expert, said in an interview that while these ideas are being intensely studied, such theories are premature. He said at least some partial preexisting immunity in some individuals seems a possibility. And he said the amount of virus someone is exposed to - called the inoculum - "is almost certainly an important and likely factor" based on what we know about other viruses. -

Non-medical masks have been required for air travellers in Canada since mid-April to prevent the spread of COVID-19.

But a ministerial order issued Friday closes a loophole that may have made it easier for some flyers to avoid face coverings.

Passengers who are unable to wear a face mask due to a medical condition must now present an official doctor's note stating that they are exempt from the rule, or they will be denied boarding.

The Public Health England study is expected to be published later this year

Quebec’s closely watched experiment reopening schools amid the COVID-19 pandemic winds down next week as the summer break begins, and the reviews are largely positive.

The province was the first in the country to reopen schools after COVID-19 brought regular life to a standstill, with children outside the Montreal region heading back to class in mid-May.

The federation representing administrators of the French school system outside Montreal says that about two-thirds of students returned to class once parents got comfortable with the idea.

The federation’s president, Nicolas Prevost, said things went relatively smoothly in the schools, though maintaining physical distancing on school buses was a challenge.

India coronavirus: 'More than half of Mumbai slum-dwellers had Covid-19'
https://www.bbc.com/news/world-asia-india-53576653
- Scientists involved with the study told the BBC that the results pointed to a number of things about the prevalence of the infection in one of India's worst-hit cities. For one, the virus has spread more widely than was earlier believed in the city's slums, where more than half of Mumbai's 12.5 million people live. -

- The high prevalence rate in the Mumbai slums could partly be explained by the fact that residents share common facilities such as toilets. "The results showed how crowding plays a key role in the spread of the infection," Dr Juneja said. The study also found that a large section of people had been infected and survived with no or little symptoms, leading to a low fatality rate in these areas - one in 1,000 to one in 2,000. This also lowers the city-wide death rate from Covid-19. -

- With the cases slowing down in Mumbai, the survey also raises the question whether the city is approaching herd immunity to the infection. Mumbai reported 717 new infections on Tuesday, the lowest in three months. Herd immunity is achieved when enough people become immune to a virus to stop its spread. "The jury is still out on that. For one, we still don't know how long the immunity to the infection lasts. We will only know the answer after repeat surveys," says Dr Kolthur. -

On my second-to-last day in the hospital, I felt a sudden, unexplainable fatigue—nothing else. I finished work, asked the resident to page me with updates, and left early. The next morning, I awoke with a fever, sweats, headache, and mild cough. Not surprisingly, I tested positive for COVID-19. At the testing site, I became confused when someone asked for my address and insurance. Upon my return home, I isolated myself from my family in my bedroom. That was the last time I left my bedroom for 4 weeks.

I became so ill. I had drenching sweats, shortness of breath, nausea, vomiting, diarrhea, and incontinence. I experienced confusion—or, more aptly, bouts of delirium. I could not remember how to open my phone. I had hallucinations of lizards crawling on my wall, so I kept my eyes closed. I knew I was dehydrated, with peeling lips and a bone-dry cotton mouth. My husband kept glasses of Gatorade by the bed and brought Tylenol at regular intervals; I did not eat for 5 days. I kept in the prone position as much as possible, something I remembered from the wards. I realize now that my judgment was impaired and that, during this worst time, I should have sought medical attention instead of reassuring my husband that I was okay.

The most distressing symptom for me was the horrible odor emanating from my skin, sweat, breath, and urine. It was nauseating and horrid, and I will never forget it. It reminded me of rotting reptile flesh.

After the worst phase, I was so weak I could not ambulate or shower without help. I was sleeping 18 hours a day, and my head was in a fog the other hours. I had lost 10 pounds.

Once, I fell out of bed, contusing my hip and head. I was terrified of being alone but even more terrified of infecting my family, so I enforced isolation as much as possible.

I had dreams and visions of my inpatient service: scores of dead COVID-19 patients being taken down the utility elevator to the morgue and the seemingly nonstop overhead pages of “rapid response team and code blue.” My mind replayed colleagues describing the agonizing and isolating deaths of so many patients.

My recovery has been steady but slow. Now, more than 2 months after becoming infected, I am still fatigued and have dyspnea with exertion and musculoskeletal pain. My husband bought a recliner chair to put beside the bed where I have spent countless days. I am in the process of further testing and physical therapy.

My brain is not working at 100%, and I still find myself with lapses. I initially couldn't remember passwords to my computer and had them reset. I recently panicked when a pharmacist asked for my DEA number—it was as if it had been completely wiped from my brain. COVID-19 is a mean and humbling illness. We do not yet know the long-term effects.

[In the US]Through July, about 3,800 people in the United States in the age group had died from coronavirus, according to figures published by the Centers for Disease Control and Prevention. That would make the coronavirus one of the leading causes of death for this age group, roughly comparable to the number of younger people who were murdered over the same time period in recent years.

And these figures include only deaths officially attributed to the virus. The overall death count in the U.S. is far higher than normal this year, suggesting that the virus’s toll is even greater than the official numbers show. More than 96,000 people age 25-44 have died so far this year, compared with an average of 78,000 at this point over the previous five years.