Making sense of unfamiliar COVID-19 vaccines: How national origin affects vaccination willingness

Vaccination willingness is a critical factor in pandemics, including the COVID-19 crisis. Therefore, investigating underlying drivers of vaccination willingness/hesitancy is an essential social science contribution. The present study of German residents investigates the mental shortcuts people are using to make sense of unfamiliar vaccine options by examining vaccination willingness for different vaccines using an experimental design in a quantitative survey. German vaccines were preferred over equivalent foreign vaccines, and the favorability ratings of foreign countries where COVID-19 vaccines were developed correlated with the level of vaccination willingness for each vaccine. The patterns in vaccination willingness were more pronounced when the national origin was shown along with the vaccine manufacturer label. The study shows how non-scientific factors drive everyday decision-making about vaccination. Taking such social psychological and communication aspects into account in the design of vaccination campaigns would increase their effectiveness.

Effectiveness of different booster regimens for preventing infection and adverse outcomes in Puerto Rico

Recent laboratory and observational studies have demonstrated that the COVID-19 vaccine effectiveness wanes over time. In response, several jurisdictions have authorized the administration of booster doses. Since August 13, 2021, Puerto Rico has administered 540,140 booster shots. We used data collected and made public by the Puerto Rico Department of Health (PRDH) to evaluate the effectiveness of four different booster regimens at preventing SARS-CoV-2 laboratory confirmed infections and adverse COVID-19 outcomes. Specifically, we analyzed data from all 115,995 SARS-CoV-2 infections occurring since the vaccination process commenced on December 15, 2020. We combined vaccination status, SARS-CoV-2 test results, and COVID-19 hospitalizations and deaths data, and fit a statistical model that adjusted for time-varying incidence rates and age group, to estimate time-varying vaccine effectiveness against infection and adverse outcomes. We find that, after 6 months, the mRNA-1273 and BNT162b2 effectiveness against infection wanes substantially to 61% (58%-63%) and 36% (34%-39%), respectively, while the Ad26.COV2.S wanes to 35% (31%-39%) after two months. However, after a booster shot of the corresponding initial vaccine manufacturer, effectiveness increased to 87% (83%- 91%) and 82% (79%- 85%) for mRNA-1273 and BNT162b2, respectively. The effectiveness for Ad26.COV2.S followed by either a mRNA-1273 or BNT162b2 booster increased to 88% (71%-100%), substantially higher than 65% (59%-70%), the peak effectiveness reached with just one shot. We also found that heterologous booster regimens restored effectiveness. Furthermore, we did not observe waning after two months of the booster shot. Finally, we found that all booster regimens provided increased protection against COVID-19 hospitalizations and deaths. Code and data to reproduce the analyses are provided here: https://github.com/rafalab/booster-eff-pr.

Third COVID-19 Vaccine Dose Boosts Neutralising Antibodies in Poor Responders

ABSTRACTObjectiveTo determine if poor responders to COVID-19 RNA vaccines (<50% neutralisation) after two doses would remain poor responders, or if a third dose could elicit high levels of NAbs.DesignClinical follow-up studySettingAcademic and medical institutions in USAParticipants269 healthy individuals ranging in age from 19 to 80 (Average age = 51; 165 females and 104 males) who received either BNT162b2 (Pfizer) or mRNA1273 (Moderna) vaccines.Main Outcome MeasuresNAb levels were measured: i) 2-4 weeks after a second vaccine dose, ii) 2-4 months after the second dose, iii) within 1-2 weeks prior to a third dose and iv) 2-4 weeks after a third RNA vaccine dose.ResultsIn 269 study participants, percent neutralisation ranged from 0% to 99% 2-4 weeks after a second vaccine dose. The majority of vaccine recipients (154/269, 57%) demonstrated NAb levels at ≥75% 2-4 weeks after their second dose. Our study also revealed that 25% of vaccine recipients did not neutralise above 50% (Median neutralisation = 21%, titers <1:80) within a month after their second dose. We called these individuals “vaccine poor responders” (VPRs). Twenty-three VPRs ranging in age from 31 to 79 (10 males, 13 females, average age = 62.5) independently obtained a third dose of either BNT162b2 or mRNA-1273 vaccine 1-8 months (average = 5 months) after their second dose. Within a month after their third dose, poor responders showed an average 20-fold increase in NAb levels (range 46%-99%).ConclusionsThe results suggest that poor responders are not permanently poor responders; they can generate high NAb levels with an additional vaccine dose–independent of mRNA vaccine manufacturer. Previous reports indicate that NAb levels decline much more rapidly than clinical protection from hospitalisation and disease, but that does not account for vaccine recipients who never generated high levels of NAbs after two doses. It is possible that poor responders are a source of breakthrough infections. Although it is not known what levels of NAbs protect from infection or disease, many vaccine recipients in high-risk professions may wish to keep peripheral NAb levels high, limiting infection, asymptomatic viral replication, and potential transmission.

Regional Differences in COVID-19 Vaccine Hesitancy in December 2020: A Natural Experiment in the French Working-Age Population

It can be assumed that higher SARS-CoV-2 infection risk is associated with higher COVID-19 vaccination intentions, although evidence is scarce. In this large and representative survey of 6007 adults aged 18–64 years and residing in France, 8.1% (95% CI, 7.5–8.8) reported a prior SARS-CoV-2 infection in December 2020, with regional variations according to an East–West gradient (p < 0.0001). In participants without prior SARS-CoV-2 infection, COVID-19 vaccine hesitancy was substantial, including 41.3% (95% CI, 39.8–42.8) outright refusal of COVID-19 vaccination. Taking into account five characteristics of the first approved vaccines (efficacy, duration of immunity, safety, country of the vaccine manufacturer, and place of administration) as well as the initial setting of the mass vaccination campaign in France, COVID-19 vaccine acceptance would reach 43.6% (95% CI, 43.0–44.1) at best among working-age adults without prior SARS-CoV-2 infection. COVID-19 vaccine acceptance was primarily driven by vaccine characteristics, sociodemographic and attitudinal factors. Considering the region of residency as a proxy of the likelihood of getting infected, our study findings do not support the assumption that SARS-CoV-2 infection risk is associated with COVID-19 vaccine acceptance.

The Impact of New SARS-CoV-2 Variants on Vaccine Breakthrough: a pilot study on spreading infection in the communities

Background: Coronavirus disease 2019 (COVID-19) vaccines are effective at helping protect against severe disease and death from variants; however, incident of breakthrough infection in vaccinated patients has been increased. Therefore, we aimed to assess the incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) new variants of concern in the communities and investigate vaccine breakthrough cases on our laboratory (Ayass Bioscience LLC) confirmed detection of COVID-19 variants in Dallas-Fort Worth (DFW), Texas. Methods: Epidemiologic study has been performed at our laboratory. We studied the viral whole-genome sequence and genotyping analysis on 166 symptomatic cases of COVID-19 which were randomly selected from nasal swab positive cases assessed from June 1st to August 30th, 2021, by reverse transcription polymerase chain reaction (RT-PCR) cycle threshold (CT) values. COVID-19 variants were identified to be dominated by B.1.617.2 (89.2%) and followed by AY.3 (1.8%), B.1.1.7 (4.8%), a combination of B.1.526.1 and B.1.617.2 (3%), B.1.621 (0.6%), and P.2 (0.6%). Result: The CT values showed significant difference among the three age groups: <30 years, 31-60 years, and >60 years by one-way ANOVA (N1: F (2, 118) =4.96, p=0.009; N2: F (2, 118) =4.95, p=0.009). No significant difference was observed by symptom, status of immunization, or vaccine manufacturer. A two-way ANOVA was performed to examine the effect of gender and variant group (Delta and other variants) on the CT values. The analyses revealed a statistically significant interaction between the effect of gender and variant group (N1, F (1.117) = 3.906, p = 0.05; N2, F (1, 117) = 7.402, p = 0.008). Conclusion: Our study shows that Delta, the dominant variant of COVID-19, is spreading in the communities, and vaccine breakthrough cases occurred in the majority of Delta variant (91%) followed by AY.3 (5%), B.1.1.7 (2%) and 2% of the double variant of B.1.526.1 and B.1.617.2. The incidence of the breakthrough cases was not linked to a specific manufacturer. The CT value is likely to associate with age. This study also supports our laboratory's ongoing efforts to sequence the SARS-CoV-2 virus from positive patient samples to identify the new viral variants and possible vaccine breakthrough mutations in the community.

Addressing Different Needs: The Challenges Faced by India as the Largest Vaccine Manufacturer While Conducting the World’s Biggest COVID-19 Vaccination Campaign

The COVID-19 pandemic has highlighted some of the challenges that countries face when balancing domestic and global necessities, for example with regard to vaccine needs, production and distribution. As India hosts one of the world’s largest vaccine manufacturing industries and has one of the most extensive vaccination strategies, the country is particularly exposed to these challenges. This has become all the more obvious as the country experienced a second pandemic wave in the first half of 2021, which has led to a total ban on exports of COVID-19 vaccines. An analysis of the national vaccination strategy and the domestic vaccine industry through review of peer-reviewed literature, grey literature, and news reports showed the fragile balance between domestic and international needs. A numerical comparison of India’s domestic COVID-19 vaccine needs, export agreements, and production capacities was conducted. It was found that at current production rates as of April 2021, meeting all of the needs and complying with all of the agreements would be impossible. Scale-ups in production, as promised by the industry, however, will enable the achievement of all targets in the long term.

Public attitudes toward COVID-19 vaccination: The role of vaccine attributes, incentives, and misinformation

While efficacious vaccines have been developed to inoculate against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2; also known as COVID-19), public vaccine hesitancy could still undermine efforts to combat the pandemic. Employing a survey of 1096 adult Americans recruited via the Lucid platform, we examined the relationships between vaccine attributes, proposed policy interventions such as financial incentives, and misinformation on public vaccination preferences. Higher degrees of vaccine efficacy significantly increased individuals’ willingness to receive a COVID-19 vaccine, while a high incidence of minor side effects, a co-pay, and Emergency Use Authorization to fast-track the vaccine decreased willingness. The vaccine manufacturer had no influence on public willingness to vaccinate. We also found no evidence that belief in misinformation about COVID-19 treatments was positively associated with vaccine hesitancy. The findings have implications for public health strategies intending to increase levels of community vaccination.

An Overview of Equine Influenza in South America

Equine influenza virus (EIV) is one of the most important respiratory pathogens of horses as outbreaks of the disease lead to significant economic losses worldwide. In this review, we summarize the information available on equine influenza (EI) in South America. In the region, the major events of EI occurred almost in the same period in the different countries, and the EIV isolated showed high genetic identity at the hemagglutinin gene level. It is highly likely that the continuous movement of horses, some of them subclinically infected, among South American countries, facilitated the spread of the virus. Although EI vaccination is mandatory for mobile or congregates equine populations in the region, EI outbreaks continuously threaten the equine industry. Vaccine breakdown could be related to the fact that many of the commercial vaccines available in the region contain out-of-date EIV strains, and some of them even lack reliable information about immunogenicity and efficacy. This review highlights the importance of disease surveillance and reinforces the need to harmonize quarantine and biosecurity protocols, and encourage vaccine manufacturer companies to carry out quality control procedures and update the EIV strains in their products.