Related Experiment Video
Updated: Apr 3, 2026

Analysis of 18FDG PET/CT Imaging as a Tool for Studying Mycobacterium tuberculosis Infection and Treatment in Non-human Primates
Published on: September 5, 2017
A four-year nationwide molecular epidemiological study in Estonia: risk factors for tuberculosis transmission
K Toit1, A Altraja2, C D Acosta3
1United Laboratories, Tartu University Hospital, Tartu, Estonia ; Department of Pulmonary Medicine, University of Tartu, Tartu, Estonia.
Setting:
Estonia has a high proportion of multidrug-resistant tuberculosis (MDR-TB). It is important to link molecular and epidemiological data to understand TB transmission patterns.
Objective:
To use 24-locus variable numbers of tandem repeat (VNTR) typing and national TB registry data in Estonia from 2009 to 2012 to identify the distribution of drug resistance patterns, Mycobacterium tuberculosis isolate clustering as an index for recent transmission, socio-demographic and clinical characteristics associated with recent transmission, and the distribution of transmission between index and secondary cases.
Design:
A retrospective nationwide cross-sectional study.
Results:
Of 912 cases with isolate and patient information, 39.1% of isolates were from the Beijing lineage. Cluster analysis identified 87 clusters encompassing 69.1% of isolates. The largest cluster comprised 178 isolates from the Beijing lineage, of which 92.1% were MDR- or extensively drug-resistant TB (XDR-TB). Factors associated with recent transmission were polyresistant TB, MDR- and XDR-TB, human immunodeficiency virus positivity, Russian ethnicity, non-permanent living situation, alcohol abuse and detention. XDR-TB cases had the highest risk of recent transmission. The majority of transmission cases involved individuals aged 30-39 years.
Conclusion:
Recent TB transmission in Estonia is high and is particularly associated with MDR- and XDR-TB and the Beijing lineage.
More Related Videos
Related Concept Videos
Pulmonary Tuberculosis I
Causative Organism
The primary infectious agent causing tuberculosis is Mycobacterium tuberculosis, a slow-growing, acid-fast, aerobic rod that exhibits sensitivity to heat and ultraviolet light. Instances of Mycobacterium bovis and Mycobacterium avium contributing to the development of TB infection are rare.
Mode of...
Pulmonary Tuberculosis V
Latent tuberculosis infection occurs when TB bacteria are present in a person's body, but are not causing illness or symptoms. It is not contagious, and preventive treatment is crucial to avoid the...
Pulmonary Tuberculosis IV
Several diagnostic approaches are used to detect TB. The conventional method is the Tuberculin Skin Test (TST), also known as the Mantoux test. However, this method has...
Pulmonary Tuberculosis III
The first classification is based on the development of the disease, and it includes the following categories:
Pulmonary Tuberculosis II
Here is a detailed explanation of its pathophysiology:
Transmission: The process begins when a person inhales droplet nuclei containing M. tuberculosis. These are typically released into the air when an individual with pulmonary or...
Transmission-based Precautions II: Airborne and Protective Environment
Airborne precautions:
Use airborne precautions when treating patients known or suspected to have diseases that spread through the air—for example, tuberculosis or measles. These organisms are present in smaller droplets expelled by an infected person and...

