October 12, 2022 – How health workers can make a difference in the public COVID-19 vaccination response “It should also be noted that the considerations described in this paper include evidence from literature that does not relate to a crisis or pandemic situation. The COVID-19 pandemic has posed new challenges to the field of vaccination, with the introduction of multiple new vaccines aimed at entire adult populations and introduced rapidly in a health crisis context. HW everywhere plays a powerful role in the potential success of this massive global effort..
October 12, 2022 – Covid-19 vaccine hesitancy and resistance amongst parents of children under 18 years of age in Ireland “Vaccine-resistant parents were more likely to be younger, living alone, to distrust scientists, and to believe the COVID-19 vaccines were unsafe. Public health messaging should target younger, lower income parents with clear information about the safety of COVID-19 vaccines for children.”
October 6, 2022 – Omicron infection more effective than earlier variants against BA.4/BA.5 reinfection “The study authors noted that BA.4 and BA.5 can escape neutralizing antibodies such as those conferred by previous infection or vaccination.”Protection from a previous SARS-CoV-2 infection against BA.4 or BA.5 reinfection was modest when the previous infection had been caused by a pre-Omicron variant but strong when it had been caused by a post-omicron subvariant (including BA.1 or BA.2),” they wrote.”
September 23, 2022 – Household transmission of the SARS-CoV-2 Omicron variant in Denmark “Unvaccinated contacts experienced similar attack rates in households with the Omicron VOC compared to the Delta VOC (28% and 27%, respectively), while fully vaccinated individuals experienced secondary attack rates of 30% in households with the Omicron VOC and 19% in households with the Delta VOC. For booster-vaccinated individuals, Omicron was associated with a SAR of 23%, while the corresponding estimate for Delta was only 11%.
July 6, 2022 – Omicron SARS-CoV-2 Neutralization from Inactivated and ZF2001 Vaccines “The rapid emergence of new variants makes variant-specific vaccine development difficult. Our findings show that a better immunization strategy for current vaccines could contribute to higher neutralization levels of omicron subvariants. Because the ZF2001 vaccine consists of a protein subunit with a focused antigen on the RBD, its use could induce increased titers of neutralizing antibodies against omicron subvariants through the administration of multiple booster doses and immune-maturation methods. However, the development of updated vaccines as boosters is needed for better protection against immune escape of current subvariants (especially BA.4 and BA.5) and possible future epidemic subvariants.”
July 2022 – Multisystem Inflammatory Syndrome after Breakthrough SARS-CoV-2 Infection in 2 Immunized Adolescents, United States “In the first case, headache and myalgia developed in a healthy 14-year-old boy (day 1 of illness); by day 7, fever, abdominal pain, diarrhea, emesis, bloodshot eyes, red cracked lips, and rash had also developed. On day 10, he was brought for treatment to the emergency department and admitted to a quaternary-care pediatric hospital.Three months earlier, he completed the Pfizer-BioNTech 2-dose COVID-19 vaccine series (Figure). One month later, he experienced 3 days of coughing and congestion and tested positive by PCR for SARS-CoV-2 infection, from which he recovered.”
July 2022 – University-Associated SARS-CoV-2 Omicron BA.2 Infections, Maricopa County, Arizona, USA, 2022 “In conclusion, >50% of 44 case-patients in our cohort experienced symptomatic BA.2 infection, but <25% sought medical care, suggesting BA.2 infection in a young population might be mild. In addition, nearly 75% of case-patients completed a primary vaccination series which, in addition to their age, might have contributed to their mild illness. However, data were insufficient to compare if vaccination status affected whether case-patients experienced symptoms or sought medical care. Among persons who completed a primary vaccine series, only 25% received booster vaccines.”
June 3, 2022 – Vaccines only modestly reduce long COVID risk “Researchers compared outcomes among nearly 34,000 people who had breakthrough SARS-CoV-2 infections after receipt of vaccines from Johnson & Johnson, Pfizer/BioNTech or Moderna, and more than 113,000 unvaccinated people who were infected. The study, conducted when the Delta variant was predominant and published in Nature Medicine, found vaccination reduced the likelihood of long COVID after infection by only about 15%. There was no difference in type or severity of long COVID symptoms between vaccinated and unvaccinated patients.”
May 13, 2022 – Neutralizing Antibodies Against the SARS-CoV-2 Omicron Variant (BA.1) 1 to 18 Weeks After the Second and Third Doses of the BNT162b2 mRNA Vaccine “Our study found a rapid decline in Omicron-specific serum neutralizing antibody titers only a few weeks after the second and third doses of BNT162b2. A limitation of our study is that its cross-sectional design precludes evaluation of antibody decrease rates on an individual level. Nevertheless, the observed decrease in population neutralizing antibody titers corresponds to the decrease in vaccine efficacy against polymerase chain reaction–confirmed Omicron infection in Denmark and symptomatic Omicron infection in the United Kingdom.Taken together, vaccine-induced protective antibody responses following a second and third dose of BNT162b2 are transient and additional booster doses may be necessary, particularly in older people; however, conserved T-cell immunity and nonneutralizing antibodies may still provide protection against hospitalization and death.”
February 24, 2022 – Effect of Covid-19 Vaccination on Transmission of Alpha and Delta Variants “One hypothesized mechanism is that viral loads observed in persons infected with the alpha variant after vaccination are lower than those among unvaccinated persons, and the viral load is associated with the likelihood of infection in contacts. However, in persons infected with the delta variant, viral loads are similar in vaccinated and unvaccinated persons, although the duration of viral shedding may be reduced. The absence of a reported difference in viral loads between vaccinated and unvaccinated infected persons calls into question whether vaccination controls the spread of the delta variant as effectively as it controls the spread of the alpha variant and whether, with increased transmissibility, the maintained viral load after vaccination explains the rapid global spread of the delta variant despite increasing vaccination coverage.
January 21, 2022 – Association Between 3 Doses of mRNA COVID-19 Vaccine and Symptomatic Infection Caused by the SARS-CoV-2 Omicron and Delta Variants “This study has several limitations. First, vaccination status and symptoms were based on patient self-reported data, potentially leading to misclassification. Second, because the testing data do not include identifiers, tests rather than persons were used as the unit of analysis, and individuals may have been included more than once. However, the analysis was restricted to symptomatic individuals to reduce inclusion of individuals serially testing for reasons other than symptomatic disease, and the short study period (23 days) reduces the probability of individuals contributing multiple test results.
December 7, 2021 – Mechanisms of SARS-CoV-2 Evolution Revealing Vaccine-Resistant Mutations in Europe and America “By tracking the evolutionary trajectories of vaccine-resistant mutations in more than 2.2 million SARS-CoV-2 genomes, we reveal that the occurrence and frequency of vaccine-resistant mutations correlate strongly with the vaccination rates in Europe and America. We anticipate that as a complementary transmission pathway, vaccine-breakthrough or antibody-resistant mutations, like those in Omicron, will become a dominating mechanism of SARS-CoV-2 evolution when most of the world’s population is either vaccinated or infected. Our study sheds light on SARS-CoV-2 evolution and transmission and enables the design of the next-generation mutation-proof vaccines and antibody drugs.”
December 2, 2021 – Omicron is supercharging the COVID vaccine booster debate “If the variant does undermine vaccine performance, extra protection against the virus might require four or more jabs, possibly with new vaccine formulations — sharpening questions over whether boosting will need to continue indefinitely. The Omicron variant has also further clouded forecasts of how booster campaigns will affect the pandemic’s trajectory.”
December 1, 2021 –Viral Dynamics of SARS-CoV-2 Variants in Vaccinated and Unvaccinated Persons “It is unclear whether this finding reflects a biologic characteristic of the delta variant, the limited number of cases, the higher proportion of delta infections among vaccine recipients, or other factors. Breakthrough infections among vaccine recipients were characterized by a faster clearance time than that among unvaccinated participants, with a mean of 5.5 days (95% credible interval, 4.6 to 6.5) and 7.5 days (95% credible interval, 6.8 to 8.2), respectively.
September 16, 2021 – Vaccine Breakthrough Infections with SARS-CoV-2 Variants “The health care workers at our institution had only mild symptoms but high viral loads (cycle thresholds of <25) and prolonged viral shedding up to 32 days after diagnosis. We performed a genomic characterization of the spike protein variants (delHV69/70, N501Y, A570D, D614G, and P681H), and all strains were classified as the B.1.1.7 (or alpha) variant.”
August 1, 2021 – Delta vSariants of SARS-CoV-2 cause significantly increased vaccine breakthrough COVID-19 cases in Houston, Texas (pdf) “Delta variants caused a significantly higher rate of vaccine breakthrough cases (19.7% compared to 5.8% for all other variants). Importantly, only 6.5% of all COVID-19 cases occurred in fully immunized individuals, and relatively few of these patients required hospitalization.”
July 28, 2021 – Covid-19 Breakthrough Infections in Vaccinated Health Care Workers “Most breakthrough cases were mild or asymptomatic, although 19% had persistent symptoms (>6 weeks). The B.1.1.7 (alpha) variant was found in 85% of samples tested. A total of 74% of case patients had a high viral load (Ct value, <30) at some point during their infection; however, of these patients, only 17 (59%) had a positive result on concurrent Ag-RDT. No secondary infections were documented.”
July 15, 2021 – Potential Benefits of Expanded COVID-19 Surveillance in the US “Recently, CDC made a decision that has taken many by surprise, focusing its surveillance efforts only on breakthrough infections that resulted in hospitalizations or deaths, and ceasing to document asymptomatic or symptomatic breakthrough cases. CDC should once again add symptomatic infections to its surveillance efforts for breakthrough infections. Even if a patient is not hospitalized, a symptomatic case indicates that for that vaccinated person, the ability to build an immune response was suboptimal, and if the individual is symptomatic, they may have more potential to transmit SARS-CoV-2 to others. Such symptomatic cases are relevant to the nation and should be reported by CDC. To do so would mean a heightened emphasis in the surveillance system on the routine testing of symptomatic persons, even if they have been fully vaccinated.”
July 8, 2021 – Effectiveness of the BNT162b2 Covid-19 Vaccine against the B.1.1.7 and B.1.351 Variants “The BNT162b2 vaccine was effective against infection and disease in the population of Qatar, despite the B.1.1.7 and B.1.351 variants being predominant within the country; however, vaccine effectiveness against the B.1.351 variant was approximately 20 percentage points lower than the effectiveness (>90%) reported in the clinical trial and in real-world conditions in Israel, and the United States.
June 25, 2021 – Review of COVID-19 Variants and COVID-19 Vaccine Efficacy: What the Clinician Should Know? “The Center of Disease Control and Prevention (CDC) updates the variant strains in the different classes. The classes are variant of interest, variant of concern and variant of high consequence. The current variants included in the variant of interest by the USA are: B.1.526, B.1.525, and P.2; and those included in the variant of concern by the USA are B.1.1.7, P.1, B.1.351, B.1.427, and B.1.429.”
May 28, 2021 – COVID-19 Vaccine Breakthrough Infections Reported to CDC — United States, January 1–April 30, 2021 “For this surveillance, a vaccine breakthrough infection is defined as the detection of SARS-CoV-2 RNA or antigen in a respiratory specimen collected from a person ≥14 days after receipt of all recommended doses of an FDA-authorized COVID-19 vaccine. State health departments voluntarily report vaccine breakthrough infections to CDC.† When possible, genomic sequencing is performed on respiratory specimens that test positive for SARS-CoV-2 RNA.
April 29, 2021 – SARS-CoV-2 501Y.V2 variants lack higher infectivity but do have immune escape “However, the number of SARS-CoV-2 infections in South Africa has increased exponentially since mid-October of 2020. In this outbreak, a new 501Y.V2 lineage (also known as B.1.351) was identified; variants of this lineage are genetically distinct from those of the first wave.
March 2021– Public health investigations of COVID-19 vaccine breakthrough cases: Case investigation protocol “Evaluating SARS-CoV-2 strains that cause vaccine breakthrough cases provides one way to monitor for variant strains that could result in lower vaccine efficacy. Page 2 of 10 Objective Investigate SARS-CoV-2 infections among people who received COVID-19 vaccine to identify trends or clustering in patient characteristics, the administered vaccine, or the infecting virus. Case definition For the purpose of this investigation, a vaccine breakthrough case will be defined as a U.S. resident who has SARS-CoV-2 RNA or antigen detected on a respiratory specimen collected ≥14 days after completing the primary series of an FDA-authorized SARS-CoV-2 vaccine.”
February 4, 2021 – Novavax COVID Vaccine Protects Against Variants “The data from South Africa are concerning, but Krammer would like to see more details before passing judgement. “If it turns out that the vaccine protects 50% against symptomatic disease caused by the variant, and to a much higher degree against moderate-severe disease, we are still in good shape,” he says.”
January 25, 2021 – What’s important to know about the new COVID-19 variants? “Another variant of the virus, 501Y.V2, has also emerged in South Africa, prompting concern that new strains may complicate global immunization efforts.”
April 4, 2020 – Emergence of Drift Variants That May Affect COVID-19 Vaccine Development and Antibody Treatment “Additionally, consideration of drift variants in convalescent immunoglobulin treatment strategies will also result in better patient outcome. In conclusion, consideration of antigenic drift in the different sub-strains of the virus is imperative in the design of a “one size fits all” universal vaccine to offer protection against the deadliest outbreak in this century.”