ONE
Antibody levels do not indicate the level of immunity people have to Covid-19. Immune cells called T cells produced after immunization by all three Covid vaccines administered in the US, are 80 percent as powerful against Omicron as earlier variants. Given how different Omicron’s mutations are from previous variants, it’s very likely that T cells would mount a similarly robust attack on any future variant as well.
This matches what scientists have found for the SARS-1 coronavirus, which killed nearly 800 people in the 2003 epidemic in Asia. In people exposed to that virus, T cells have lasted for 18 years and counting. Evidence so far indicates that the T-cells for Covid-19 decline so slowly that they effectively work forever.
Antibodies spike after every shot of vaccine or after each exposure to the virus and inevitably and normally decline within a few weeks to months.
Antibodies only recognize two or three key parts of the spike protein. But T cells detect many more parts of the spike and are less likely to fail when facing a new mutated variant like Omicron.
Infection and vaccines also encode a memory of the virus in B cells, which can churn out fresh batches of antibodies within four or five days after a new exposure to the virus.
This 1-2 punch of T and B cells explains why many people who received two or even three doses of vaccine could still be infected with the Omicron variant, but only a small percentage became seriously ill.
There is a decrease of antibody levels over time, but memory B cells and memory T cells kick back into action relatively quickly.
Memory B cells become increasingly sophisticated over time, and they learn to recognize a diverse set of viral genetic sequences. The longer they have to practice, the broader the range of virus variants they can defeat.
A study published in Nature showed that six months after vaccination, memory B cells continue to mature, and the antibodies they produce keep gaining the ability to recognize new variants. Antibodies at six months are better binders and more potent neutralizers than the ones that are produced one month after immunization.
TAKE HOME
Antibody research doesn't tell the whole story. Antibody counts are not enough to require more boosters. Recent studies suggest that in most people, the immunity gained from infection or vaccination will hold up for a long while. Even if mutations in new variants change some of the viral regions that T cells recognize, there would still be enough others to maintain a strong immune response for years. The best response occurs in people who were both infected and vaccinated.
TWO
A new study shows that the female hormone Estrogen protects against death from COVID-19.
Researchers in Sweden studied 14,685 older women with COVID-19, all of whom were past menopause, during which estrogen levels decline dramatically. Seventeen percent were taking estrogen supplements to relieve menopausal symptoms. After adjusting for other risk factors, women getting extra estrogen had a 53% lower risk of dying from COVID-19 compared to untreated women. The idea that estrogen might be protective in hospitalized COVID-19 patients is now being tested more rigorously in a randomized controlled trial at Tulane University.
TAKE HOME
Estrogen therapy might help future high-risk patients with newly diagnosed Covid. Imagine someone like Queen Elizabeth being given Estrogen at the time of her Covid diagnosis and lowering her risk of dying by 50%.
THREE
Pepcid's promise against COVID-19 is being confirmed by new data.
In non-hospitalized, unvaccinated adults with mild-to-moderate COVID-19, treatment with a high dose of the antacid drug famotidine (Pepcid) helped speed resolution of symptoms and inflammation in a small randomized controlled trial.
Roughly half of those in the trial took Pepcid three times a day for two weeks. The others took a placebo. Patients in the Pepcid group had faster resolution of 14 of 16 symptoms assessed in the study, including loss of smell and taste, difficulty breathing and abdominal pain. Pepcid treatment also led to faster improvements in markers of inflammation without any detrimental effects on patients' immune responses.
TAKE HOME
Like Vitamin D, Pepcid, which we have been discussing on WHP since May of 2020, is being confirmed as a viable option to aid in the treatment of Covid-19.
FOUR
U.S. statistics overestimated how many patients have been hospitalized for COVID-19.
At 60 hospitals near Boston, Pittsburgh and Chicago, researchers manually reviewed the charts of a random sample of 1,123 patients with confirmed coronavirus infections hospitalized between March 2020 and August 2021. Roughly 1-in-4 patients "actually were admitted for a different problem and should not have been included" in data analytics calculations of the severity of COVID-19. Patients were more likely to have been admitted specifically for COVID-19 when local infection rates were high. When infection rates were low last summer, half the patients were hospitalized for other reasons, with Covid -19 infection found incidentally on mandatory testing. The researchers were able to identify indicators in patients' charts that admissions were actually due to COVID-19, such as whether doctors ordered lab tests related to inflammation.
TAKE HOME
This study highlights an important weakness in COVID-19 reporting. The CDC and PA Department of Health hospitalization data which should have been the most useful in assessing the severity of the pandemic was very inaccurate and always skewed towards making the situation seem worse than it really was. The result was widespread fear, bad policies and the loss of credibility in our health reporting institutions.