Efficacy of COVID-19 vaccines.

As of 2022, the global population has access to several mRNA and traditional inactivated vaccines. However, their effectiveness in preventing infection, hospitalization, and COVID-associated mortality in Jordan has yet to be evaluated. The purpose of this observational study was to evaluate the relative effectiveness of three approved vaccines against COVID-19 in a sample of the Jordanian population. The study was conducted between July 2021 and 2022 in a sample of adult patients presenting to hospitals across Jordan and receiving one of the three vaccines - Pfizer (BNT162b2), Astra Zeneca (ChAdOx1-S), or Sinopharm (BBIBP-CorV). Data were collected to measure the rates of infection without hospitalization, infection with hospitalization, and death. The sample included patients with one of the following chronic conditions: cardiovascular disease, respiratory disease, or diabetes. Primary data were obtained from patients' health records. The sample included 6132 adults from Jordan, with a mean age 52 ± 17 years. The rates of death in patients receiving two doses of any vaccine ranged between 0.175 and 2.77%, compared with 0.69-13.53% in patients receiving only one dose. The rates of hospitalization were 6-7.97% with two doses, compared to 7.98-25.13% with one dose. The rates of infection without hospitalization were significantly higher in the two-dose group (6-25.1%) compared with those who had received only one dose of any COVID-19 vaccine (0.69-10.61%). In conclusion, receiving two doses of a COVID-19 vaccine was associated with lower odds of mortality and hospitalization and higher odds of infection. More research is needed to evaluate the safety and efficacy of vaccines against SARS-CoV-2.

How long-term metal and lead exposure among foundry workers affect COVID-19 infection outcomes in Jordan.

Foundry workers face a number of occupational health hazards, which may lead to an increased risk of respiratory disease, cancer, and anxiety level and are associated with endocrine, hematologic, renal, and neurological problems in humans. This study aims to evaluated thyroid functions, glutathione level, and the risk of infection with SARS-CoV-2 after vaccinated (two doses of the BNT162b2 mRNA COVID-19 vaccine) foundry workers in Jordan. We examined the efficacy BNT162b2 vaccine by calculating the rate of mortality and the degree of severity from mild to severe respiratory infections in 105 adult males foundry workers occupationally exposed to metals and Pb who had been received two doses, 21 days apart, of the BNT162b2 vaccine. Seventy-five male subjects not exposed to the Pb and who received two shots of the BNT162b2 vaccine (Pfizer-BioNTech) served as the control group. In foundry workers who were infected with COVID-19, the mortality rate (0%) was similar as in the control group (0%), and increased transmission of infection with SARS-CoV-2; the non-hospitalized infections increased nearly 3.4-times and hospitalized infections increased 4.29-times among people exposed to lead and metal contamination compared to the healthy persons control group. Also, among the foundry workers, the blood lead, FT3, and FT4 levels were significantly higher (p < 0.0001) and the levels of glutathione and TSH were significantly decreased (p < 0.0001) compared with the control group. In conclusion, long-term exposure to Pb is associated with a risk of infection with COVID-19 despite the 2 doses of the BNT162b2 vaccine (Pfizer-BioNTech). Also, exposure to Pb is associated with hyperthyroidism and a reduction in glutathione.