Many people (including epidemiologists and other scientists) are frustrated with the lack of centralized, reliable science communication around the issue of Covid. Here I have pulled together recent reports from the US and other countries to answer some common questions about Omicron, the extent of protection offered by vaccination and boosters, whether or not Omicron is mild for those who are vaccinated and whether or not it will lead to such high levels of immunity that Covid will soon become downgraded from "pandemic' to "endemic" (i.e. present in society but well under control like influenza and other managed illnesses). I will provide citations for all answers. Of course, this does not mean everything quoted will stand the test of time. Even the best empirical science on this disease is evolving at a rate considerably slower than the virus itself and its spread.
1) If you are fully vaxxed can you still get Omicron?
In December, the NY Times reported that only mRNA vaccines ( Pfizer and Moderna) protect against Omicron infection.
"The Pfizer and Moderna shots use the new mRNA technology, which has consistently offered the best protection against infection with every variant. All of the other vaccines are based on older methods of triggering an immune response.
"The Chinese vaccines Sinopharm and Sinovac — which make up almost half of all shots delivered globally — offer almost zero protection from Omicron infection. The great majority of people in China have received these shots, which are also widely used in low-and middle-income countries such as Mexico and Brazil.
A preliminary effectiveness study in Britain found that the Oxford-AstraZeneca vaccine showed no ability to stop Omicron infection six months after vaccination. Ninety percent of vaccinated people in India received this shot, under the brand name Covishield; it has also been widely used across much of sub-Saharan Africa, where Covax, the global Covid vaccine program, has distributed 67 million doses of it to 44 countries." https://www.nytimes.com/2021/12/19/health/omicron-vaccines-efficacy.html
Since then, it has become clear that no vaccines in existence can block Omicron infections, even if some appear to do a better job than others based on initial data. The topic has switched to preventing serious illness, hospitalization, and death. Here the data has been less than perfectly clear and unequivocal.
2)Does full vaccination (2 shots of Pfizer or Moderna or 1 shot of J&J) prevent moderate to severe illness, hospitalization and death?
Vaccines do not prevent mild illness which is now widespread among both those vaccinated and unvaccinated. The NIH recognizes a continuum from mild to severe illness along the following lines (these definitions are taken from the NIH website; see link below):
MILD:
"Patients with mild illness may exhibit a variety of signs and symptoms (e.g., fever, cough, sore throat, malaise, headache, muscle pain, nausea, vomiting, diarrhea, loss of taste and smell). They do not have shortness of breath, dyspnea on exertion, or abnormal imaging. Most mildly ill patients can be managed in an ambulatory setting or at home through telemedicine or telephone visits. No imaging or specific laboratory evaluations are routinely indicated in otherwise healthy patients with mild COVID-19. Older patients and those with underlying comorbidities are at higher risk of disease progression; therefore, health care providers should monitor these patients closely until clinical recovery is achieved."
MODERATE:
"Moderate illness is defined as evidence of lower respiratory disease during clinical assessment or imaging, with SpO2
≥94% on room air at sea level [at or below 94% oxygen saturation. where normal parameters are 96-100%] Given that pulmonary disease can
progress rapidly in patients with COVID-19, patients with moderate
disease should be closely monitored. If bacterial pneumonia or sepsis is
suspected, administer empiric antibiotic treatment, re-evaluate the
patient daily, and de-escalate or stop antibiotics if there is no
evidence of bacterial infection."
SEVERE:
Patients with COVID-19 are considered to have severe illness if they have SpO2 <94% on room air at sea level... [again this means oxygen saturation levels below 94%, where 94-100% are considered within normal range]. These patients may experience rapid clinical deterioration. Oxygen therapy should be administered immediately using a nasal cannula or a high-flow oxygen device. If secondary bacterial pneumonia or sepsis is suspected, administer empiric antibiotics, re-evaluate the patient daily, and de-escalate or stop antibiotics if there is no evidence of bacterial infection.
SOURCE: https://www.covid19treatmentguidelines.nih.gov/overview/clinical-spectrum/
DISCUSSION:
Mild, moderate and severe are not discrete or neatly contained categories but continuous with the ever-present danger of progression. Depending on who gets a "mild" or "moderate" case, the threat level of progression will vary. Of course, all severe cases are very dangerous. So, on average, a young and healthy person with mild symptoms can probably recover at home in much the same way as the flu. However, a middle aged person who is obese, diabetic or who has cardio-vascular problems, or a host of other relatively common conditions must be very vigilant about avoiding "mild" infection, and monitoring it closely with a doctor if one occurs. This is even more important with "moderate" infections among people with such underlying conditions who develop respiratory symptoms or even slight decrease in Oxygen levels (which most of us at home cannot ascertain).
Thus, since real cases are fluid and can change rapidly in real-time, and since our data base is very limited in the US, categorical statements about the benefits of vaccination on preventing moderate to serious illness are often lacking in statistical evidence that might support them. The best way to ask the question is to ask:
3)HOW MANY CURRENTLY HOSPITALIZED COVID PATIENTS ARE FULLY VACCINATED?
I've noticed that the CDC, the New York Times Covid Dashboard and other widely used cites DO NOT collect and share data on the percentage of people in hospitals who were vaccinated, and which vaccines they used. However, the state of Massachusetts does share some such data, and The Boston Globe keeps track of the ratio of vaccinated to unvaccinated Covid patients in the hospital.
About half of the Mass. patients hospitalized for Covid ARE FULLY VACCINATED.
The most recent data on is from January 13, 2022. At that time there were 3,180 Covid hospital patients. Of those, 1,547 were vaccinated. 460 of all hospitalized patients were in ICU units (these numbers are all much lower than many other states, including my own, i.e. NY). https://www.bostonglobe.com/2020/03/10/nation/latest-coronavirus-numbers-massachusetts/
Though the NY Times does not report these things, an article in that paper yesterday (1/17) written about the toll Omicron is taking on Nurses in a Brooklyn Hospital contained information consistent with that which the Boston Globe has been reporting since Omicron broke (indicating about 1/2 of those hospitalized on avg. are vaccinated fully). I quote from the relevant sections of the Times piece: In the article, we read that the vaccinated in ICU in Brooklyn Hospital Center comprise a little under 1/2 of ICU patients there. That ICU is filled to capacity.
"Dr. de Souza said that the emergency room had more Covid-19 patients last week than at any point since the first wave. On Tuesday, four Covid patients, including a retired doctor, died, Dr. de Souza said.
On Wednesday, a tear streamed down her cheek as she looked out on patients. More kept arriving, with many staying for days. There was little room for them upstairs. The 18 intensive care beds on the hospital’s sixth floor were full, mainly with Covid-19 patients.
"I think it's hard to process what's actually happening right now, which is [that] most people are gonna get COVID...What we need to do is make sure that the hospitals can still function [and that] transportation [and] other essential services are not disrupted while this happens." https://arstechnica.com/science/2022/01/fda-head-omicron-is-a-natural-disaster-most-people-are-gonna-get-covid/
This was widely criticized by epidemiologists as being unjustified by any evidence, and also being counterproductive since on such an assumption protective measures would appear futile to many. If we're all "gonna get it" why socially distance, wear masks etc.? Dr. Fauci was more nuanced saying most people will be exposed (though they won't necessarily all "get Covid"). He refused to predict whether this will lead to greater immunity against future Covid variants or not, as many have speculated. That depends on the nature of subsequent variants, he said flatly.
4) What about boosters and second boosters to mitigate contagion and illness?
Here I will cite 2 recent, but preliminary findings that could be force us to reevaluate the current model based largely on 3nd and 4th jabs for added protection against Omicron.
A) Israel: From Bloomberg Reports today:
Fourth Pfizer Dose Is Insufficient to Ward Off Omicron, Israeli Trial Suggests
- Preliminary data found inoculation did increase antibodies
- Those with 4th shot only slightly less likely to get variant
A fourth dose of the Pfizer-BioNTech vaccine was insufficient to prevent infection with the omicron variant of Covid-19, according to preliminary data from a trial in Israel released Monday.
Two weeks after the start of the trial of 154 medical personnel at the Sheba Medical Center in Tel Aviv, researchers found the vaccine raised antibody levelsFrequent Boosters Spur Warning on Immune Response
European Union regulators warned that frequent Covid-19 booster shots could adversely affect the immune response and may not be feasible.
Repeat booster doses every four months could eventually weaken the immune response and tire out people, according to the European Medicines Agency. Instead, countries should leave more time between booster programs and tie them to the onset of the cold season in each hemisphere, following the blueprint set out by influenza vaccination strategies, the agency said.
The advice comes as some countries consider the possibility of offering people second booster shots in a bid to provide further protection against surging omicron infections. Earlier this month Israel became the first nation to start administering a second booster, or fourth shot, to those over 60. The U.K. has said that boosters are providing good levels of protection and there is no need for a second booster shot at the moment, but will review data as it evolves.
Boosters “can be done once, or maybe twice, but it’s not something that
we can think should be repeated constantly,” Marco Cavaleri, the EMA
head of biological health threats and vaccines strategy, said at a press
briefing on Tuesday. https://www.bloomberg.com/news/articles/2022-01-11/repeat-booster-shots-risk-overloading-immune-system-ema-says
I hope this round-up of info on the Omicron variant of Covid helps round out the picture for those who, like me, have been confused by seemingly conflicting and empirically unjustified statements from journalists, pundits and health experts in the news.
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