Antibodies Testing in Karachi Reveals COVID19 Exposure Runs in Double Digits

Antibodies testing of 7,000 adults in Karachi reveals that as many as 15% of them have already been exposed to COVID19 without experiencing symptoms, according to a study by Dr. Wajiha Javed, an epidemiologist and head of public health and research at Getz Pharma in Pakistan. This data raises the possibility that millions of Pakistanis may have already been exposed to coronavirus. It takes at least 40% of the population to be exposed to build herd immunity. This may be the only way to normalcy unless there is a vaccine available sooner.

Human Immune Response:

Human body naturally produces antibodies to fight viruses of various kinds, including the coronavirus. Presence of antibodies in a person confirms that he or she has been exposed to a virus regardless of symptoms. Serology tests can detect body's immune response to even a low-level viral load. Such an immune response also occurs to a vaccine which does not make you sick but helps build immunity. More low level exposure to viruses in large numbers of people is in fact a good thing because it helps build herd immunity. However, the most vulnerable population such as the elderly must be isolated until herd immunity is achieved. It takes at least 40% of the population to be exposed to build herd immunity.

Coronavirus Antibodies

Getz Study:

Getz Pharma's Dr. Wajiha Javed told me in the latest update on her ongoing work that serology tests have so far been administered to 7,000 adults aged 18-65 over the last 6 weeks in Karachi. 15% of them have tested positive for COVID19 antibodies. People tested included those working for banks, restaurants, textile mills, factories, media and health care workers.

Antibody testing kits detect the response of the body rather than the virus or antigen itself. These tests do not have the issue of low viral load. Antibody tests can detect exposure to Covid-19 even in asymptomatic cases. Generally, antibody testing kits have a high level of accuracy, especially on sequential testing. The kit Getz Pharma has been using has a sensitivity (the ability to correctly detect positive cases) of 95.3% and specificity (the ability to correctly detect negative cases) of 98.7% for IgG, and the sensitivity is 86.48% and specificity is 95.18% for IgM, according to Dr. Wajiha Javed.

Pakistan COVID19 Death Rate Among The World's Lowest. Source: Our World in Data 

Asymptomatic Carriers: 

Over 90% of those who tested positive in Karachi did not have any symptoms or had only mild symptoms, Dr. Wajiha Javed recently wrote in Dawn newspaper.  But some were infectious and they were spreading the virus to others. Because of their non-existent or mild symptoms, they had not reached out to a PCR testing facility to get tested for Covid-19, and were only incidentally picked out for the antibody test during Getz's study. This data raises the possibility that millions of Pakistanis may have already been exposed to coronavirus.

Summary:

As many as 15% of Karachi adults have been exposed to COVID19 with over 90% of them showing no symptoms, according to a Getz Pharma study in Pakistan. People tested included those working for banks, restaurants, textile mills, factories, media and health care workers. Human body naturally produces antibodies to fight viruses of various kinds, including the coronavirus. Presence of antibodies in a person confirms that he or she has been exposed to a virus regardless of symptoms. It can even detect body's immune response to a low-level viral load. Getz Pharma's antibodies test data suggests the possibility that millions of Pakistanis may have already been exposed to coronavirus.  Such an immune response also occurs to a vaccine which does not make you sick but helps build immunity. More low level exposure to viruses in large numbers of people is in fact a good thing because it helps build herd immunity. This may be the only way to normalcy unless there is a vaccine available sooner.

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  • Riaz Haq

    One More Reason to Wear a Mask: You’ll Get Less Sick From COVID-19

    https://www.ucsf.edu/news/2020/07/418181/one-more-reason-wear-mask-...

    As more and more states promote face masks as a way to control the spread of COVID-19, the top-line message has been: wear a mask to protect others. While it’s true that most face masks are more effective in preventing you from launching droplets into the air than breathing in already dispersed droplets – that doesn’t mean masks offer no protection to the wearer.

    It’s likely that face masks, by blocking even some of the virus-carrying droplets you inhale, can reduce your risk of falling seriously ill from COVID-19, according to Monica Gandhi, MD, an infectious disease specialist at UC San Francisco.

    “The more virus you get into your body, the more sick you are likely to get,” she said.

    In the latest wave of infections in the U.S., the wider use of masks may be one factor for the lower death rates – along with more testing, younger patients and better treatments – said Gandhi. A greater proportion of these new cases have been mild or asymptomatic, though more data is needed to see if they track geographically with higher rates of mask-wearing.

    Worldwide, epidemiological patterns seem to provide a clue. In countries where mask wearing was already commonplace, such as Japan, Taiwan, Thailand, South Korea, and Singapore, and in countries where mask wearing was quickly embraced, such as the Czech Republic, rates of severe illness and death have remained comparatively low.

    These epidemiological observations are among the evidence that Gandhi and colleagues cite in a paper in the Journal of General Internal Medicine, in which they propose that masks can lead to milder or asymptomatic infections by cutting down on the dose of virus people take in.

    “Masks can prevent many infections altogether, as was seen in health care workers when we moved to universal masking. We’re also saying that masks, which filter out a majority of viral particles, can lead to a less severe infection if you do get one,” said Gandhi. “If you get infected, but have no symptoms – that’s the best way you can ever get a virus.”

    The idea that viral dose, also known as viral inoculum, determines the degree of illness is not new, said Gandhi. Descriptions of a dose-mortality curve – how much of a virus is needed to cause death in an animal – were first published in 1938. And after all, the earliest vaccines, which were documented in 16th century China, involved exposing someone to a small amount of smallpox virus to induce mild illness and subsequent immunity.

    A small number viral particles is more likely to be quelled by the immune system before they can proliferate, said Gandhi.

    Researchers have studied dose dependency experimentally with other viral infections, like the flu. In a study with healthy volunteers, those who received a higher dose of the influenza A virus developed more severe symptoms.

    Because the new coronavirus, SARS-CoV-2, is potentially lethal, experiments on masking and disease severity have been necessarily limited to animals. In a hamster study, a surgical mask partition between the cages of infected and uninfected hamsters significantly cut COVID-19 transmission. Fewer hamsters caught the virus and those that did showed milder symptoms.

    Tale of Two Cruise Ships
    Gandhi believes the viral inoculum theory helps explain an unusual feature of the new coronavirus – what Anthony Fauci, MD, director of the National Institute of Allergy and Infectious Disease, has called its “protean” manifestations.

    Early in the year, as COVID-19 spread around the world, infectious disease experts began to notice this strange aspect of the new virus – the extreme variation in its symptoms and severity. Some who tested positive didn’t seem sick at all, some had symptoms of a cold, others lost their sense of taste or developed delirium, and still others suffered severe pneumonia that led to death.

  • Riaz Haq

    Immune system is like a muscle... you lose it you don’t use it

    Vaccines for everything from influenza to measles provide partial protection against COVID-19, according to new Mayo Clinic research, suggesting that parents should get children up to date on shots before school this fall, and senior citizens should schedule their vaccinations before the winter flu season.

    People showed a 28% reduction in COVID-19 risk if they received the PCV13 pneumonia vaccine in the past year compared with those who didn’t, and a 43% reduction if they received the polio vaccine before travels to at-risk locations, the study showed.


    While the population-based study has limitations and was posted online Tuesday without peer review, Mayo officials said there is little harm in using the results to encourage people to seek shots that are recommended anyway.

    “Make sure you get your scheduled vaccines,” said Dr. Andrew Badley, an author of the study and a leader of Mayo’s COVID research task force. “Not doing so is not doing everything you can to reduce your risks.”


    The recommendation comes as Minnesota leaders wrestle with the dilemma of wanting to reopen K-12 schools this fall while facing a rising rate of COVID-19 cases and hospitalizations.

    Gov. Tim Walz will unveil his school reopening plan Thursday, but he made reference during a press briefing Wednesday to a “decision matrix” that will guide districts on whether to reopen with live classrooms, online sessions or a mix. The guidance is expected to give schools discretion, depending on COVID-19 levels in their communities.

    “Our guiding principles are to keep our children and our staff in the buildings safe,” Walz said. “Our second goal right behind that is to get our children back in the schools, especially our littlest learners, if at all possible.”

    The governor on Wednesday highlighted 4 million protective masks that are being distributed to help people comply with Minnesota’s new indoor mask mandate.

    The Minnesota Department of Health on Wednesday reported nine COVID-19 deaths and 681 infections with the SARS-CoV-2 coronavirus that causes the infectious disease. That brings the state’s totals to 1,589 deaths and 52,947 known infections.

    The state reported 310 people hospitalized with COVID-19, and 143 of them needing intensive care. Those are both highs for the month of July.

    Cases have been increasing for weeks, initially among teenagers and young adults but now among older, higher-risk individuals who are more likely to need hospital care, said Kris Ehresmann, state infectious disease director.


    https://m.startribune.com/non-covid-vaccines-offer-some-covid-prote...

  • Riaz Haq

    #Pfizer and #Moderna #Vaccines Likely to Produce Lasting Immunity Against #COVID19, Study Finds. Most people immunized with the mRNA vaccines may not need boosters, so long as the virus and its variants do not evolve much beyond current forms. #DeltaPlus https://www.nytimes.com/2021/06/28/health/coronavirus-vaccines-immu...

    The vaccines made by Pfizer-BioNTech and Moderna set off a persistent immune reaction in the body that may protect against the coronavirus for years, scientists reported on Monday.

    The findings add to growing evidence that most people immunized with the mRNA vaccines may not need boosters, so long as the virus and its variants do not evolve much beyond their current forms — which is not guaranteed. People who recovered from Covid-19 before being vaccinated may not need boosters even if the virus does make a significant transformation.

    “It’s a good sign for how durable our immunity is from this vaccine,” said Ali Ellebedy, an immunologist at Washington University in St. Louis who led the study, which was published in the journal Nature.

    The study did not consider the coronavirus vaccine made by Johnson & Johnson, but Dr. Ellebedy said he expected the immune response to be less durable than that produced by mRNA vaccines.


    Dr. Ellebedy and his colleagues reported last month that in people who survived Covid-19, immune cells that recognize the virus lie quiescent in the bone marrow for at least eight months after infection. A study by another team indicated that so-called memory B cells continue to mature and strengthen for at least a year after infection.

    Based on those findings, researchers suggested that immunity might last for years, possibly a lifetime, in people who were infected with the coronavirus and later vaccinated. But it was unclear whether vaccination alone might have a similarly long-lasting effect.

    Dr. Ellebedy’s team sought to address that question by looking at the source of memory cells: the lymph nodes, where immune cells train to recognize and fight the virus.

    After an infection or a vaccination, a specialized structure called the germinal center forms in lymph nodes. This structure is an elite school of sorts for B cells — a boot camp where they become increasingly sophisticated and learn to recognize a diverse set of viral genetic sequences.

    The broader the range and the longer these cells have to practice, the more likely they are to be able to thwart variants of the virus that may emerge.