The Centers for Disease Control and Prevention last Thursday loosened many of its recommendations for battling the coronavirus, a strategic shift that puts more of the onus on individuals, rather than on schools, businesses and other institutions, to deal with the virus.
No longer do schools and other institutions need to screen apparently healthy students and employees as a matter of course. The CDC is putting less emphasis on social distancing — and the new guidance has dropped the “six foot” standard. The quarantine rule for unvaccinated people is gone. The agency’s focus now is on the vulnerable ‘co-morbidity’ populations and how to protect them — not on the vast majority of people who at this point have some immunity against the virus and are unlikely to become severely ill.
“The current conditions of this pandemic are very different from those of the last two years,” CDC epidemiologist Greta Massetti said Thursday in a briefing for reporters.
CDC officials point to greater protection against the virus because of high levels of vaccine-and infection-induced natural immunity. From the CDC website,
Preexposure prophylaxis. COVID-19 vaccine effectiveness against severe outcomes is lower in persons who are immunocompromised than in those who are not, and persons who are immunocompromised and have COVID-19 are at increased risk for intensive care unit admission and death while hospitalized, irrespective of their vaccination status (11,12). Preexposure prophylaxis with Evusheld¶ can help protect persons with moderate to severe immunocompromise who might not mount an adequate immune response after COVID-19 vaccination, as well as persons for whom COVID-19 vaccination is not recommended because of their personal risk for severe adverse reactions. In addition to early antiviral treatment if infected, persons who are moderately or severely immunocompromised can benefit from COVID-19 preexposure prophylactic medication to help prevent severe COVID-19 illness, as an adjunct to up-to-date vaccination for themselves and their close contacts, early testing, nonpharmaceutical interventions, and prompt access to treatment if they are infected.
The CDC acknowledges in the above paragraph that some individuals do not respond well to the Covid vaccine, and thus may benefit from prophylaxis treatment. The guideline also states that prevention recommendations no longer differentiate based on a person’s vaccination status,
Nonpharmaceutical interventions. Implementation of multiple prevention strategies helps protect individual persons and communities from SARS-CoV-2 exposure and reduce risk for medically significant illness and death by reducing risk for infection (Table). Implementation of multiple nonpharmaceutical preventive interventions can complement use of vaccines and therapeutics, especially as COVID-19 Community Levels increase and among persons at high risk for severe illness. CDC’s COVID-19 prevention recommendations no longer differentiate based on a person’s vaccination status because breakthrough infections occur, though they are generally mild (16), and persons who have had COVID-19 but are not vaccinated have some degree of protection against severe illness from their previous infection (17). In addition to strategies recommended at all COVID-19 Community Levels, education and messaging to help individual persons understand their risk for medically significant illness complements recommendations for prevention strategies based on risk.
As we have seen in America, breakthrough infections are occurring among vaccinated individuals, although generally mild.
Natural Immunity
According to the CDC, people with natural immunity number around 92 million. One WEBMD report in April suggests 63% of Americans have been infected with Covid. This results in the presence of natural immunity for most of these individuals.
The National Institutes of Health explains natural immunity,
“Immune cells and proteins that circulate in the body can recognize and kill the pathogen if it’s encountered again, protecting against disease and reducing illness severity.”
The components of immunity protection include:
Antibodies are proteins that circulate in the blood and recognize foreign substances like viruses and neutralize them.
Helper T cells help to recognize pathogens.
Killer T cells kill pathogens.
B cells make new antibodies when the body needs them.
People who recover from COVID-19 have been found to have all four of these components. Patients infected with SARS-CoV-2 develop protective immune responses, mediated by virus-specific T cells and antibodies, after the infection.
In the July, 12 issue of Proceedings of the National Academy of Sciences (PNAS), Anna Martner and co-authors at University of Gothenburg report two main findings. First, several variants of virus-specific T cells became detectable in blood shortly after COVID-19, but strikingly disappeared after 10-12 weeks.
However, a group of highly specialized T cells, designed to facilitate elimination of infected cells, remained active in the blood of all previously SARS-CoV-2-infected patients. These T cells did not disappear or wane even at long follow-up.
It was observed that a subgroup of specialized T cells (Th1 cells) that promote destruction of virus-infected cells were active for at least 20 months after natural COVID-19. The infected patients also harbored several other types of T cells that reacted with SARS-CoV-2. The findings explain the reduced risk of severe disease and mortality among patients who have become re-infected with SARS-CoV-2.
Summary of CDC Changes
As part of the changes, the agency is dropping its recommendation that people be screened or tested for covid in most settings. That change is likely to affect policies in workplaces, schools and day-care centers.
Under the new guidance, quarantine procedures have been relaxed: Unvaccinated people who have had close contact with someone who is infected no longer are advised to go through a five-day period of quarantine if they have not tested positive for the virus or shown symptoms.
Previous CDC guidance said people who had been exposed but were up to date on their coronavirus shots could skip the quarantine period. The new guidance expands that standard to everyone.
“The pandemic is in a very different spot” than it was last year, said David M. Aronoff, an infectious-disease expert and physician at Indiana University. “We know the majority of Americans have some immunity to SARS-CoV-2, either because they’re immunized by a vaccine or immunized by an infection.”
Caitlin Rivers, an infectious-disease epidemiologist at the Johns Hopkins Center for Health Security, said it made sense to standardize the quarantine guidance regardless of vaccination status.
“The vaccines remain protective against severe illness, but the combination of variants and waning [immunity] have eroded their protection against infection,” Rivers wrote in an email.
The more relaxed guidelines are “a concession to realism, to the way that a lot of people are handling this,” said William Hanage, an epidemiologist at the Harvard T.H. Chan School of Public Health. He called the new guidelines “entirely reasonable.”
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“Do not be wise in your own eyes; Fear the LORD and depart from evil. It will be health to your flesh, and strength to your bones. Honor the LORD with your possessions, and with the firstfruits of all your increase.” (Proverbs 3:7—9).
