Protection against Plasmodium falciparum malaria in chimpanzees by immunization with the conserved pre-erythrocytic liver-stage antigen 3

In humans, sterile immunity against malaria can be consistently induced through exposure to the bites of thousands of irradiated infected mosquitoes. The same level of protection has yet to be achieved using subunit vaccines. Recent studies have indicated an essential function for intrahepatic parasites, the stage after the mosquito bite, and thus for antigens expressed during this stage. We report here the identification of liver-stage antigen 3, which is expressed both in the mosquito and liver-stage parasites. This Plasmodium falciparum 200-kilodalton protein is highly conserved, and showed promising antigenic and immunogenic properties. In chimpanzees (Pan troglodytes), the primates most closely related to humans and that share a similar susceptibility to P. falciparum liver-stage infection, immunization with LSA-3 induced protection against successive heterologous challenges with large numbers of P. falciparum sporozoites.

Using BCG vaccine to enhance non-specific protection of health care workers during the COVID-19 pandemic: A structured summary of a study protocol for a randomised controlled trial in Denmark

Objectives: The Bacille Calmette-Guérin (BCG) vaccine against tuberculosis is associated with non- specific protective effects against other infections, and significant reductions in all-cause morbidity and mortality have been reported. We aim to test whether BCG vaccination may reduce susceptibility to and/or the severity of COVID-19 and other infectious diseases in health care workers (HCW) and thus prevent work absenteeism.

The primary objective is to reduce absenteeism due to illness among HCW during the COVID-19 pandemic. The secondary objectives are to reduce the number of HCW that are infected with SARS-CoV-2, and to reduce the number of hospital admissions among HCW during the COVID-19 pandemic.

Hypothesis: BCG vaccination of HCW will reduce absenteeism by 20% over a period of 6 months.

Trial design: Placebo-controlled, single-blinded, randomised controlled trial, recruiting study participants at several geographic locations. The BCG vaccine is used in this study on a different indication than the one it has been approved for by the Danish Medicines Agency, therefore this is classified as a phase III study.

Participants: The trial will recruit 1,500 HCW at Danish hospitals.

To be eligible for participation, a subject must meet the following criteria: Adult (≥18 years); Hospital personnel working at a participating hospital for more than 22 hours per week.

A potential subject who meets any of the following criteria will be excluded from participation in this study:

Known allergy to components of the BCG vaccine or serious adverse events to prior BCG administration

Known prior active or latent infection with Mycobacterium tuberculosis (M. tuberculosis)

or other mycobacterial species

Previous confirmed COVID-19

Fever (>38 C) within the past 24 hours

Suspicion of active viral or bacterial infection

Pregnancy

Breastfeeding

Vaccination with other live attenuated vaccine within the last 4 weeks

Severely immunocompromised subjects. This exclusion category comprises:

a) subjects with known infection by the human immunodeficiency virus (HIV-1)

b) subjects with solid organ transplantation

c) subjects with bone marrow transplantation

d) subjects under chemotherapy

e) subjects with primary immunodeficiency

f) subjects under treatment with any anti-cytokine therapy within the last year

g) subjects under treatment with oral or intravenous steroids defined as daily doses of 10 mg prednisone or equivalent for longer than 3 months

h) Active solid or non-solid malignancy or lymphoma within the prior two years

Direct involvement in the design or the execution of the BCG-DENMARK-COVID trial

Intervention and comparator: Participants will be randomised to BCG vaccine (BCG-Denmark, AJ Vaccines, Copenhagen, Denmark) or placebo (saline). An adult dose of 0.1 ml of resuspended BCG vaccine (intervention) or 0.1 ml of sterile 0.9% NaCl solution (control) is administered intradermally in the upper deltoid area of the right arm. All participants will receive one injection at inclusion, and no further treatment of study participants will take place.

Main outcomes: Main study endpoint: Days of unplanned absenteeism due to illness within 180 days of randomisation.

Secondary study endpoints: The cumulative incidence of documented COVID-19 and the cumulative incidence of hospital admission for any reason within 180 days of randomisation.

Randomisation: Randomisation will be done centrally using the REDCap tool with stratification by hospital, sex and age groups (+/- 45 years of age) in random blocks of 4 and 6. The allocation ratio is 1:1.

Blinding (masking): Participants will be blinded to treatment. The participant will be asked to leave the room while the allocated treatment is prepared. Once ready for injection, vaccine and placebo will look similar, and the participant will not be able to tell the difference.

The physicians administering the treatment are not blinded.

Numbers to be randomised (sample size): Sample size: N=1,500. The 1,500 participants will be randomised 1:1 to BCG or placebo with 750 participants in each group.

Trial Status: Current protocol version 5.1, from July 6, 2020.

Recruitment of study participants started on May 18, 2020 and we anticipate having finished recruiting by the end of December 2020.

Trial registration: The trial was registered with EudraCT on April 16, 2020, EudraCT number: 2020-001888-90, and with ClinicalTrials.gov on May 1, 2020, registration number NCT04373291.

Full protocol: The full protocol is attached as an additional file, accessible from the Trials

website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.

Keywords: COVID-19, Randomised controlled trial, Protocol, BCG vaccine, NSEs/Non-specific effects of vaccines, Heterologous effects of vaccines, Health care workers, Pandemic, Immune training.

Microbial community of cyanobacteria mats in the intertidal zone of oil-polluted coast of Saudi Arabia

Cyanobacterial mats are found at various locations along the coast of the Eastern Province of Saudi Arabia. Those mats were affected by severe oil pollution following 1991 oil spill. In this study, samples from Abu Ali Island were collected at three selected sampling sites across the intertidal zone (Lower, Middle, and Upper) in order to understand the effect of extreme environmental conditions of high salinity, temperature and desiccation on distribution of cyanobacteria along the oil polluted intertidal zone. Our investigation of composition of cyanobacteria and diatoms was carried out using light microscopy, and Denaturant Gradient Gel Electrophoresis (DGGE) technique. Light microscopy identification revealed dominant cyanobacteria to be affiliated with genera Phormidium, Microcoleus, and Schizothrix, and to a lesser extent with Oscillatoria, Halothece, and various diatom species. The analysis of DGGE of PCR-amplified 16S rRNA fragments showed that the diversity of cyanobacteria decreases as we proceed from the lower to the upper intertidal zone. Accordingly, the tidal regime, salinity, elevated ambient air temperature, and desiccation periods have a great influence on the distribution of cyanobacterial community in the oil polluted intertidal zone of Abu Ali Island.

Reactivation of BCG vaccination scars after vaccination with mRNA-Covid-vaccines: two case reports

BACKGROUND

From May 2020 to January 2021, we enrolled 1233 health care workers (HCW) from Danish Hospitals in a randomized trial evaluating whether Bacille Calmette-Guérin (BCG) provides protection against COVID-19. Participants were randomized 1:1 to BCG vs saline and followed for 6 months. From December 2020, Covid-19 vaccines were offered to the HCW. In most cases, BCG vaccination results in a characteristic scar. Reactivation of the BCG scar has been described in children during viral infections and following influenza vaccination, but is mostly associated to Kawasaki's disease, a disease entity with pathogenesis likely similar to the child Covid-19 complication MIS-C: Multi-System Inflammatory Syndrome. Reactivation of scars after neonatal BCG vaccination has recently been described in four women after Covid-19 mRNA vaccination. Two of our trial participants experienced reactivation of their novel BCG scars after receiving mRNA Covid-19 vaccination 6 to 8 months post-BCG.

CASE PRESENTATIONS

Two female HCW participants that had been randomly allocated to BCG in the BCG-DENMARK-COVID trial, spontaneously reported itching and secretion at the BCG scar site after having received mRNA Covid-19 vaccination (Moderna and Pfizer-BioNTech) 6 to 8 months following inclusion and BCG vaccination. One participant, who had a larger BCG skin reaction, noticed re-appearing symptoms after both the first and the second COVID-vaccine dose, while the other participant only noted symptoms after the second dose. Both had been BCG vaccinated during childhood, and no reactivation was noted in the older scars. No treatment was needed or provided.

CONCLUSIONS

The reactivation of the BCG scar after receiving mRNA vaccine might have been caused by cross-reactivity between BCG and SARS-CoV-2. In both cases, the symptoms were bothersome, but self-limiting and left no sequelae. The risk of reactivation at the scar site is thus not a reason to avoid vaccination with either vaccine.

Using BCG Vaccine to Enhance Nonspecific Protection of Health Care Workers During the COVID-19 Pandemic: A Randomized Controlled Trial

BACKGROUND

The BCG (Bacillus Calmette-Guérin) vaccine can induce nonspecific protection against unrelated infections. We aimed to test the effect of BCG on absenteeism and health of Danish health care workers (HCWs) during the coronavirus disease 2019 (COVID-19) pandemic.

METHODS

A single-blinded randomized controlled trial included 1221 HCWs from 9 Danish hospitals. Participants were randomized 1:1 to standard dose BCG or placebo. Primary outcome was days of unplanned absenteeism. Main secondary outcomes were incidence of COVID-19, all-cause hospitalization, and infectious disease episodes.

RESULTS

There was no significant effect of BCG on unplanned absenteeism. Mean number of days absent per 1000 workdays was 20 in the BCG group and 17 in the placebo group (risk ratio, 1.23; 95% credibility interval, 0.98-1.53). BCG had no effect on incidence of COVID-19 or all-cause hospitalization overall. In secondary analyses BCG revaccination was associated with higher COVID-19 incidence (hazard ratio [HR], 2.47; 95% confidence interval [CI], 1.07-5.71), but also reduced risk of hospitalization (HR, 0.28; 95% CI, .09-.86). The incidence of infectious disease episodes was similar between randomization groups (HR, 1.09; 95% CI, .96-1.24).

CONCLUSIONS

In this relatively healthy cohort of HCWs, there was no overall effect of BCG on any of the study outcomes.

CLINICAL TRIALS REGISTRATION

NCT0437329 and EU Clinical Trials Register (EudraCT number 2020-001888-90).

[Dyspnea caused by Coxiella Burnetii]

Dyspnea is a subjective sensation of difficult or uncomfortable breathing caused by increased excitation of brain respiratory centres,(1) and is usually secondary to pulmonary or cardiac disease.(2) Heart failure is a serious public health problem in industrialised countries, with an increasing prevalence and incidence. It is more common in the elderly, and is usually caused by a defect in myocardial contraction, coronary atherosclerosis, or less frequently, valvular disease.(3) Aortic insufficiency (AI) is one of them. It may originate from infective endocarditis, congenital or valvular heart disease, or rheumatic fever. It may lead to a medical emergency due to the inability of the left ventricle to adapt to the rapid increase in the end-diastolic volume caused by regurgitation of blood from aorta to left ventricle. If not corrected, the AI can lead to acute cardiogenic shock.(4.)