BA.5 Subvariant Uptick, Herd Immunity and Q & A 30 on America Out Loud PULSE
UPTICK | BA.5 is estimated to represent more than one in three recent U.S. cases that are averaging just more than 100,000 a day, CDC data show. The true number of infections may be roughly six times as high, some virus experts said, in part because so many people are using at-home tests that state health departments largely don’t track.
BOOSTERS | Biden Administration health officials said Tuesday that BA.5 has the potential to push the number of infections higher in the coming weeks. They urged eligible people to get vaccine booster shots to lower the risk of hospitalization and death, and not to wait for potential updated boosters targeting Omicron subvariants.
MORE MASKING | New York City last week urged people to resume masking in public, indoor settings and around crowds outside. Los Angeles County’s public health department said rising Covid-19 hospital admissions mean the county also could soon reach high community prevalence and that officials would reinstate a mask mandate if the county stayed at that level for two weeks.
The details of when and how this seemingly magical threshold would be crossed were fuzzy. Some scientists who study viruses thought only 20-some percent of the population needed to be immune; others estimated it’d be closer to 90. A minority of experts wanted to reach herd immunity as quickly as possible by letting the virus rip through the population rather than wait for vaccines to become available. But no matter the number or method, the concept of herd immunity represented a framework through which public officials and the media (including me) could understand what it would take for the threat to end.
Update: Effectiveness of Monoclonal Antibodies and Antiviral Drugs against Omicron BA.2.12.1, BA.4, and BA.5 Subvariants
A lab study published in July 2022 (NEJM) using the live-virus Focus Reduction Neutralization Testing (FRNT) method revealed that bebtelovimab seems to be the most promising monoclonal antibody against the BA 5 subvariant.
Overall, the study data also revealed that the three antiviral drugs remdesivir, molnupiravir, and nirmatrelvir (Paxlovid) may still have therapeutic value against the sublineages BA.2.12.1, BA.4, and BA.5 of SARS-CoV-2 omicron variants.
Do take note of the limitation of this study as this is a non-clinical study (not in humans). There is lack of clinical data on the efficacy of these monoclonal antibodies and antiviral drugs for the treatment of patients infected with BA.4 or BA.5 subvariants. Therefore, the selection of monoclonal antibodies or anti-virals to treat patients who are infected should be carefully considered based on the potential risks as compared to its potential benefits.
Omicron BA 4 and BA 5 Subvariants: Symptoms and Treatment