Objectives:
Vaccination and single-dose rifampin are the main proven effective intervention types for preventing leprosy among contacts of Mycobacterium leprae endemic areas. Currently, no high-quality evidence is available regarding the best prophylactic (preventing or contributing to the prevention of disease) intervention. Therefore, this review article has been conducted.

Objectives:
Do patients with knee osteoarthritis benefit from vitamin D supplementation?

Study design:
This review article included 6 articles with a total of 1,599 patients with osteoarthritis of the knee.

Objectives:
Does vitamin C supplementation improve triglyceride and cholesterol levels in patients with type 2 diabetes mellitus?

Objectives:
Quantification of asymptomatic infections is fundamental for effective public health responses to the COVID-19 pandemic. Discrepancies regarding the extent of asymptomaticity have arisen from inconsistent terminology as well as conflation of index and secondary cases which biases toward lower asymptomaticity. Therefore, this review article has been conducted.

Objectives:
Personalized nutrition and protective diets and lifestyles represent a key cancer research priority. The association between consumption of specific dietary components and colorectal cancer (CRC) incidence has been evaluated by a number of population-based studies, which have identified certain food items as having protective potential, though the findings have been inconsistent. Therefore, this review article has been conducted.

Objectives:
Omega-3 polyunsaturated fatty acid (PUFA) supplementation has been proposed as a potential therapy for cancer-related malnutrition, which affects up to 70% of patients with cancer. Therefore, this review article has been conducted.

Objectives:
Anticoagulation is generally used in hospitalized patients with coronavirus disease 2019 (COVID-19) as thromboprophylaxis. However, results from different studies comparing the effect of anticoagulation on the mortality of COVID-19 patients with non-anticoagulation are inconclusive. Therefore, this review article has been conducted.

Objectives:
What is the immunogenicity and safety of the 7 different Ebola virus vaccines in healthy adults?

Study design:
This review article included 21 randomized controlled trials (RCTs), evaluating 7 different vaccines with different doses with a  total of 5,275 participants.

Results and conclusions:
The investigators found the rVSVΔG-ZEBOV-GP (2 × 107) vaccine was more immunogenic [p-score = 0.80].

The investigators found for pain, rVSVΔG-ZEBOV-GP (≤105) had few events [p-score = 0.90].

Objectives:
Zinc in one of the most abundant trace minerals in human body which is involved in numerous biological pathways and has variety of roles in the nervous system. It has been assumed that zinc exerts its role in nervous system through increasing brain derived neurotrophic factor (BDNF) concentrations. Therefore, this review article has been conducted.

Objectives:
During the ongoing COVID-19 pandemic, face masks are among the most common and practical control measures used globally in reducing the risk of infection and disease transmission. Although several studies have investigated the efficacy of various face masks and respirators in preventing infection, the results have been inconsistent. Therefore, this review article has been conducted.