Influence of malaria endemicity and tuberculosis prevalence on COVID-19 mortality

2021

Preprint

Self Cite

Background: Both malaria and latent tuberculosis ( LTB) are possible factors related to decreased COVID-19 mortality. The malaria endemicity variable is a possible confounder when conducting a study on the correlation of LTB prevalence to COVID-19 mortality. Studies regarding LTB prevalence" according to different studies" did not adjust malaria endemicity as a possible confounder. Many malaria-endemic countries are high TB prevalent. Malaria-free countries could be: high, moderate, or low in TB prevalence. The main aim of this study is to look for the influence of TB prevalence on COVID-19 mortality. TB prevalence reflects LTB prevalence in the absence of malaria endemicity as a possible confounding factor in TB studies. Material and methods: The total chosen countries were 69 non-malaria endemic countries. Countries were classified according to TB prevalence groups into low, moderate, and high prevalent groups. Covid-19 deaths/Million(M) inhabitants were taken as reported on September 2, 2020. "Kendall's-τ Correlation Coefficient", "Kruskal-Wallis test, and Mann-Whitney test were used in statistical analyses.Results: We found inverse relationships between TB prevalence and COVID-19 deaths/ (M) inhabitants and a highly positive significant correlation coefficient was reported (0.008) in Kendall's-τ correlation coefficient test. Kruskal-Wallis test showed a significant relationship within studied groups. Furthermore, the low TB prevalent group had significant reverse associations with both high and moderate TB prevalent groups in the Mann-Whitney test.Conclusion: In the absence of possible malaria confounding, TB prevalence in malaria-free countries is inversely related to COVID-19 mortality in a highly significant association.

Section: Discussionsupporting

confidence: 71%

Tuberculosis Prevalence Correlation to COVID-19 Mortality in Malaria Free Countries

2021

Preprint

Self Cite

“…24 Some of literatures raise the possibility of malaria as one factor in explaining the variances in COVID-19 mortalities. [13][14][15][16][17][18][19][20] One of these studies founded that malaria has an added effect on TB prevalence effect in decreasing the COVID-19 deaths in malaria-endemic areas. 19 Countries are classified as either malaria-free or malaria-endemic countries.…”

Section: Discussionmentioning

confidence: 99%

“…In the same context, another 2 studies founded a significant correlation between malaria endemicity and COVID-19 mortality. 19,20…”

Section: Malariamentioning

confidence: 99%

Tuberculosis prevalence relation to COVID-19: mortality in malaria free countries

Int J Community Med Public Health

2022

Self Cite

Background: Both malaria and latent tuberculosis (TB) are possible factors related to decreased COVID-19 mortality. Malaria endemicity variable is a possible confounder when conducting a study on the correlation of latent TB prevalence to COVID-19 mortality. Studies regarding latent TB prevalence" according to different studies" did not adjust malaria endemicity as a possible confounder. Many malaria-endemic countries are high TB prevalent. Malaria-free countries could be: high, moderate, or low in TB prevalence. The main aim of this study is to look for the influence of TB prevalence on COVID-19 mortality. TB prevalence reflects latent TB prevalence in the absence of malaria endemicity as a possible confounding factor in TB studies.Methods: The total chosen countries were sixty-nine non-malaria endemic countries. Countries were classified according to TB prevalence groups into low, moderate, and high prevalent groups. Covid-19 deaths/Million (M) inhabitant were taken as reported on September 2, 2020. "Kendall's-τ Correlation Coefficient", "Kruskal-Wall is test, and Mann-Whitney test were used in statistical analyses.Results: We found inverse relationships between TB prevalence and COVID-19 deaths/ (M) inhabitant and a highly positive significant correlation coefficient was reported (0.008) in Kendall's-τ correlation coefficient test. Kruskal-Wall is test showed a significant relationship within studied groups. Furthermore, the low TB prevalent group had significant reverse associations with both high and moderate TB prevalent groups in the Mann-Whitney test.Conclusions: In the absence of possible malaria confounding, TB prevalence in malaria free countries is inversely related to COVID-19 mortality in a highly significant association.

“…Early in this pandemic, it was also suggested by a few studies that latent tuberculosis (LTB) could mitigate COVID-19 morbidity and mortality [16][17][18][19][20][21]. Some tested TB prevalence [16,20,22] as a proxy for LTB, while others considered LTB estimates that might cross-react with BCG and other mycobacteria. Other studies considered positivity in the TST/interferon-gamma release assay (IGRA) as a measure of the potential protective effect of the resident populations' exposure to Mycobacterium spp., whether from BCG vaccination or as a result of exposure to environmental mycobacteria [17,18,23].…”

Section: Introductionmentioning

confidence: 99%

“…For example, disparities exist among both countries with low LTB incidence or BCG coverage and those with high LTB incidence or BCG coverage [23]. Regarding malaria's influence on COVID-19 mortality, it was suggested by a few preliminary studies to reduce it [22,26].…”

Section: Introductionmentioning

confidence: 99%

BCG Correlation with Latent Tuberculosis Can Lead to Spurious Correlation with Reduced COVID-19 Mortality

2021

CJAST

Background: Many factors have been suggested to confound coronavirus disease 2019 (COVID-19) studies, and BCG studies have been criticized for not adjusting for many confounders. We conducted this study to analyze the presumed effectiveness of the Bacillus Calmette–Guérin (BCG) vaccine in decreasing the COVID-19 mortality rate, and to answer the question of whether this is confounded by latent tuberculosis (LTB) prevalence. Materials and Methods: We chose sixty-nine malaria-free countries with different BCG vaccination policies. TB prevalence was considered as a proxy for LTB. The BCG, TB prevalence, and COVID-19 mortality data are publically available. Contingency coefficients (C.C.) and a Receiver Operating Characteristic (ROC) analysis were used to assess the relationship between TB prevalence and BCG status, and identify cutoff points in each BCG group category. A stem–leaf plot was also used to explore the data’s apparent behavior concerning COVID-19 in relation to the BCG groups. Results: TB prevalence was significantly associated with BCG status. There was a highly significant association according to (C.C.) between TB prevalence and BCG group categories. Countries not implementing BCG vaccinations had low TB prevalence, and vice versa (p value = 0.000). ROC analyses indicating that BCG group is significantly associated with corresponding TB prevalence. Conclusions: BCG country status has a highly significant relationship with TB prevalence. This can confound BCG and COVID-19 mortality and morbidity studies. In the absence of a correlation ,this can lead to a spurious correlation between BCG and reduced COVID-19 mortality or morbidity.