Here is a reference to one of the studies on waning antibody levels after natural infection. Read it a reminder of what the science actually shows about "natural immunity" https://www.elitetrader.com/et/threads/your-vaccine-passport.358316/page-10#post-5395489
Forgive me for being skeptical of stuff you post, but do you have anything else that supports your claim besides some doctor in Delhi, India? Or Slavitt's anecdotal stories?
So your reading comprehension is so poor that you are claiming the study is associated with some doctor in Delhi, India. Yeah... but this is one of your common misdirection ploys. Let's read the entire article about the study by the doctors from the Duke-NUS Medical School on a group of patients in Singapore for six to nine months. Individual COVID-19 Antibodies Could Last Days To Decades, Scientists Find https://www.ibtimes.com/individual-...uld-last-days-decades-scientists-find-3168292 Antibodies against SARS-CoV-2 wane at largely varying rates among individuals, scientists have found. These could last just a few days in some individuals but remain present decades later for others, according to a new study that suggests the severity of COVID-19 infection could be the deciding factor in having longer-lasting protection against reinfection. Published in The Lancet Microbe, the study noted that patients with low levels of neutralizing antibodies may still be protected from COVID-19 if they have a robust T-cell immunity. "The key message from this study is that the longevity of functional neutralizing antibodies against SARS-CoV-2 can vary greatly and it is important to monitor this at an individual level," said Wang Linfa, a corresponding author of the study, Eurekalert reported. "This work may have implications for immunity longevity after vaccination, which will be part of our follow-up studies," the professor added. The scientists, which included those from Duke-NUS Medical School, examined 164 COVID-19 patients in Singapore for six to nine months. The patients' blood was continuously analyzed for neutralizing antibodies against the virus. The procured data was then used to train a machine-learning algorithm to predict the trajectories of patients' neutralizing antibodies over time. From the analysis, the researchers created five categories based on how long antibodies lasted in an individual. The first category, called the "negative" group, included the individuals who never developed detectable neutralizing antibodies. This group comprised 11.6% of participants. Comprising 26.8% of patients, the second group is called the "rapid waning" group and showed varying early levels of antibodies that waned quickly. The third category comprised 29% of participants and was called the "slow waning" group as these patients tested positive for antibodies against SARS-CoV-2 for up to half a year. The fourth group, called the "persistent" group, comprised 31.7% of patients and showed little change in their antibody levels up to 180 days. The last group, or the "delayed response" group, covered only 1.8% of subjects and included those who showed a marked rise in neutralizing antibodies during late convalescence. Study co-author David Lye of the National Centre for Infectious Diseases (NCID) emphasized the importance of public health and social measures in ongoing pandemic outbreak response. "The presence of T-cell immunity provides hope of longer-term protection which will require more studies and time for epidemiological and clinical evidence to confirm," the author said. The research is deemed by scientists to be helpful to policymakers as they continue to come up with strategies to beat COVID-19. Since antibodies wane faster in some individuals, researchers believe reinfection may occur in subsequent waves of infection. The scientists also added that should the immunity provided by the vaccine wane over time, then it would be necessary to conduct annual vaccine administration to prevent future outbreaks. "This study reminds us that we all react differently to infection and that various people mount different protective immune responses. Understanding the basis of these differences will help build better vaccines," said Professor Laurent Renia of the Agency for Science, Technology and Research (A*STAR) Infectious Diseases Labs. The CDC describes antibodies as proteins created by an individual's immune system soon after they have been infected or vaccinated. These proteins are responsible for fighting off infections and can protect one from getting reinfected.
That wasn't the article you linked to, though. It had this: https://scroll.in/latest/995360/exp...ing-after-six-months-to-a-year-from-infection
Go take a look at what I posted and what link was presented after the quote at the bottom of my post. We already know these type of claims of "that wasn't the link you posted" nonsense when there are two links presented is one of your usual misdirection tactics. Along with all the other forms of deliberate reading mis-comprehension you use. It got old a long time ago.
Who is we? Everyone here thinks you're a chump. So you expected me to go with the link at the bottom of your copy paste post, and not the top one? Then you should have said so. it isn't my fault if you don't specifically state which one of your links I need to waste my time on. You post a link in this thread to another post in another thread that has two separate links. I read the first and you go "no...the other one!"
COVID reinfections far higher for recovered patients who shun vaccine: Israeli study Natural immunity alone much weaker than recovery-plus-shot, mass peer-reviewed research finds; before Omicron, those with ‘hybrid’ protection were 82% less likely to be reinfected https://www.timesofisrael.com/covid...ered-patients-who-shun-vaccine-israeli-study/ Israelis who recovered from COVID-19 and were vaccinated with a single dose of the Pfizer-BioNTech vaccine are far better protected against reinfection than those who only have natural immunity, a large-scale Israeli study found. The study, published this week in the Annals of Internal Medicine, reported those who were vaccinated after infection were 82 percent less likely to contract the virus following their initial bout. The study also found people who received a vaccine shot after recovering from COVID-19 were 76% less likely to have a symptomatic case of coronavirus than those who were unvaccinated. The research was based on a sample of nearly 108,000 Israelis aged 16 and over who were infected before having been vaccinated, making it the largest study of its kind. The data were from just before the Omicron wave, when reinfections of recovered patients were relatively rare, and while they provide a picture of infection patterns, the study’s authors said hospitalization rates were too low to draw conclusions on serious illnesses. The study focused on people who caught the coronavirus before getting vaccinated, comparing those who got a single vaccine shot afterwards to those who did not. The research was limited to those who received one shot even though many Israeli convalescents have been administered more, as a single dose is the minimum recommended for recovered patients in Israel and many other countries. The peer-reviewed study was conducted by the research arm of Maccabi Healthcare Services. As the study drew on data from before Israel’s fifth major outbreak, it does not give any insight on immunity among people who recovered from the Omicron variant of coronavirus. Many Omicron convalescents have received two or three vaccine doses, making it possible they could have an even higher level of extra protection than unvaccinated convalescents, but the study made no predictions on this. Yet despite not covering the Omicron wave, the researchers believe the study makes a strong argument for a general principle that the “hybrid” immunity among vaccinated convalescents provides much better protection against COVID-19 than natural immunity alone. “We see that convalescent patients are more protected if they get vaccinated once than if they aren’t vaccinated,” the team, led by Dr. Sivan Gazit and Dr. Tal Palaton, told The Times of Israel. In the article, the team wrote: “We found a statistically significant decreased risk for reinfection in persons previously infected who received a single vaccine dose compared with those who were previously infected but unvaccinated.” “In addition, there was a decreased risk for symptomatic disease among persons who were previously infected and vaccinated.” The Israeli medical community lauded the research as significant, especially as it comes when there are far more newly recovered patients, a disproportionate number of whom are unvaccinated. In many cases, after recovering the virus, these people have a stronger belief that they do not need a vaccine. Epidemiologist Hagai Levine, chairman of the Israel Association of Public Health Physicians, told The Times of Israel that he considers the research “important.” Levine, who was not involved in the research, said that while it’s hard to infer what it means for Omicron convalescents, “it is to be hoped that the extensive scope of infection and vaccines will be an at least partial protective layer against future variants.” He stressed that this will need to be tested in real life. Dr. Yariv Wine, a virus expert from Tel Aviv University, who also wasn’t involved in the study, told The Times of Israel: “This publication makes a lot of sense. The basic idea upon which vaccine science is built is ‘training’ the immune system to respond to a specific pathogen in a way that would mimic the stimulation necessary for immune development but would not produce active disease. “In light of the recurrent COVID-19 morbidity waves, it is of particular importance to understand how the immunity that follows natural infection differs from the immunity following vaccination,” Wine added. He said the new study progresses this understanding, making it clear that patients who recovered and took a single dose “benefit from both full systemic activation of the immune system, natural infection, together with enhanced antibody production thanks to the vaccine.”
It is the largest research study in the world on reinfections involving the Delta variant but I wonder why they did not research the other available vaccines in Israel ??? I've been trying to find research studies for all the age groups involving comorbidities (hypertension, diabetes mellitus, and asthma/COPD) involving reinfections in unvaccinated versus breakthrough infections in vaccinated. In addition, I'm waiting for the completion of research studies about the long-term effects of reinfection in the unvaccinated versus vaccinated breakthrough infections but I don't expect the latter to start showing up for another few years involving Covid when it crosses the brain barrier. Most likely, it will be a study that comes out of Israel or the UK because they both have current research just starting in hospitalized patients identified in commonly seen reinfections as neurologic conditions like anosmia (loss of smell), stroke, delirium, brain inflammation, encephalopathy, primary psychiatric syndromes, and peripheral nerve syndromes. I only one study but its results involve Omicron (not Delta) and it will not be completed for another few years. By the way, health insurance and disability insurance companies are becoming more interested in these studies, especially in countries like the United States that do not have universal healthcare. Further, there was a small study out of India that looked at risk factors for Covid Reinfection. More percentage of people were reinfected while doing "outdoor activities" versus those using public transportation or indoor social gathering. Anyways, the data is now slowly coming out although too slow in my opinion. Regardless, I found the discussion (conclusion) from the article you posted very interesting... ---------- Discussion This is the largest real-world observational study comparing the protection conferred by previous SARS-CoV-2 infection combined with vaccine-induced immunity afforded by a single dose of the BNT162b2 mRNA vaccine. Our large cohort, facilitated by Israel's rapid rollout of the mass vaccination campaign and its early decision to vaccinate convalescent persons, allowed us to investigate the risk for reinfection or an additional infection at least 90 days after the previous one over a longer period than thus far described. Our analysis showed that persons who were previously infected and received a single dose of the vaccine had a 82% decreased rate of breakthrough infection compared with those who were previously infected but unvaccinated. The decreased risk was significant for symptomatic disease as well. However, likely because of the small number of hospitalizations in this group (of convalescent persons, vaccinated or not), we could not determine statistical significance when comparing the risk for reinfection resulting in hospitalizations. This finding supports previous small cohort studies pointing to evidence of a boosting effect of neutralizing antibody activity, or an anamnestic response, in previously infected persons receiving a single dose of an mRNA vaccine (18, 19, 41), as well as SARS-CoV-2–specific T-cell (42) and memory B-cell response and affinity maturation (43). Our study has several limitations. First, because the Delta variant was the dominant strain tested in our analysis, the boosting effect of the vaccine cannot be ascertained against other strains. Second, our analysis addressed protection afforded solely by the Pfizer–BioNTech BNT162b2 vaccine, and therefore does not address other vaccines. Third, we also did not include a third group of previously infected and 2-dose vaccinated persons because this was not the official policy in Israel and including them could lead to a selection bias. However, a previous small cohort study suggested that the marginal protection afforded by another dose is not consequential (18), although future studies should determine the clinical significance and duration of a second dose in previously infected persons. In addition, because this is an observational, real-world study where PCR screening was not done by a preset protocol, we may be underestimating asymptomatic infections because these persons often do not get tested. A related concern is that the frequency of PCR testing differed between groups, meaning that 1 group manifested different health seeking behavior during the pandemic and therefore is potentially more diagnosed rather than more infected. To address that potential detection bias, we did a sensitivity analysis where the number of PCR tests undertaken throughout the pandemic serves as a proxy for COVID-19–related health seeking behavior (6, 8). This adjustment did not change the results. Moreover, because we used full matching in each trial, including matching of geographic location at the level of neighborhoods, socioeconomic status, and chronic diseases, residual confounding by unmeasured factors is unlikely. Nonetheless, to assess whether the association between previous infection and a following vaccination could be due to unmeasured confounding—for example, by health care seeking behavior (such as social distancing and mask wearing), we calculated the E-value for an unmeasured confounder. The E-value for the analysis suggested that only a very strong association between both convalescent patients who were subsequently vaccinated and health care seeking behavior and health care seeking behavior and reinfection would account for all of the observed association between vaccinating convalescent patients and their reduced risk for reinfection. This analysis showed that persons who were previously infected with SARS-CoV-2 gain additional protection from a subsequent single-dose vaccine regimen. Nonetheless, even without a subsequent vaccination, it seems that reinfection is relatively rare, at least in the first year after infection (13, 44), although the study was done before the emergence of the Omicron variant. The long-term effects of reinfection are still unknown. Therefore, policies regarding vaccination of convalescent persons of different age and risk groups will also depend on prioritization of resources in terms of global vaccination deployment. ---------- wrbtrader