Characteristics of non-clustered tuberculosis in a low burden country

Social determinants of tuberculosis: a nationwide case-control study, Denmark, 1990-2018

BACKGROUND

The global vision is a world free of tuberculosis (TB). Even in resource-rich TB low-incidence settings, we need more focus on the role of social risk factors to end the TB epidemic.

METHODS

Nationwide, retrospective register-based, case-control study from 1990 to 2018, including all TB patients in Denmark ≥18 years old (n = 9581) matched 1:3 on sex and age with population controls. TB risk factors were assessed in logistic regression models and estimated by odds ratio (OR).

RESULTS

All TB patients had considerably lower socio-economic status compared with controls (P < 0.0001). Among ethnic Danes, TB was mostly found among males, persons between 35 and 65 years, those living alone, those with low educational level, persons on social welfare benefits and those with low income. Conversely, for migrants, being younger, sex and living alone were less important, whereas having children was protective. In an adjusted multivariable regression model among Danes, key risk factors for TB were being on disability pension (OR = 2.7) and cash benefits (OR = 4.7). For migrants, fewer social risk factors increased TB risk, although low income and cash benefits did (OR = 3.1).

CONCLUSION

Even today in a resourceful setting, socio-economic status drives disparities in health. In our study, multifactorial social deprivation was highly associated with TB. Especially household structure, education, employment and income were important risk factors that should be addressed in the future to accelerate TB control and end the TB epidemic.

Tuberculosis in Migrants is Among the Challenges of Tuberculosis Control in High-Income Countries

The incidence of tuberculosis (TB) is high among migrants in high-income countries. The migration process could contribute to the high incidence of TB among them. Achieving TB elimination from these settings will be difficult unless countries address the burden of TB among migrants. The aim of this review was to describe the challenges of international migration on TB control in high-income, low TB incidence countries. Among migrants, there is a high prevalence of risk factors for TB, such as exposure to TB, HIV, malnutrition, substance use, delayed diagnosis, low education, poor health-seeking, the culture, stigma and marginalization. Discriminatory policies of TB care and social barriers such as language, cultural issues and unfriendly health services may also contribute to the high prevalence of TB among them. TB control among migrants in these settings is important as migrants are vulnerable to TB infection and disease, and implementing TB care among them is difficult; it is important to reduce the TB burden in migrants and the community at large and the high risk of multidrug-resistant TB (MDR-TB). TB elimination from high-income countries requires acquiring data and analyzing it to measure the burden, having migrant-sensitive health systems, having policy and legal frameworks and multi-country partnerships and conducting research.

Tools to implement the World Health Organization End TB Strategy: Addressing common challenges in high and low endemic countries

AIM

The purpose of this viewpoint is to summarize the advantages and constraints of the tools and strategies available for reducing the annual incidence of tuberculosis (TB) by implementing the World Health Organization (WHO) End TB Strategy and the linked WHO TB Elimination Framework, with special reference to Oman.

METHODS

The case-study was built based on the presentations and discussions at an international workshop on TB elimination in low incidence countries organized by the Ministry of Health, Oman, which took place from September 5 to September 7, 2019, and supported by the WHO and European Society of Clinical Microbiology and Infectious Diseases (ESCMID).

RESULTS

Existing tools were reviewed, including the screening of migrants for latent TB infection (LTBI) with interferon-gamma release assays, clinical examination for active pulmonary TB (APTB) including chest X-rays, organization of laboratory services, and the existing centres for mandatory health examination of pre-arrival or arriving migrants, including examination for APTB. The need for public-private partnerships to handle the burden of screening arriving migrants for active TB was discussed at length and different models for financing were reviewed.

CONCLUSIONS

In a country with a high proportion of migrants from high endemic countries, screening for LTBI is of high priority. Molecular typing and the development of public-private partnerships are needed.

Does the Development of Vaccines Advance Solutions for Tuberculosis?

BACKGROUND

Mycobacterium tuberculosis (Mtb) is considered as one of the most efficacious human pathogens. The global mortality rate of TB stands at approximately 2 million, while about 8 to 10 million active new cases are documented yearly. It is, therefore, a priority to develop vaccines that will prevent active TB. The vaccines currently used for the management of TB can only proffer a certain level of protection against meningitis, TB, and other forms of disseminated TB in children; however, their effectiveness against pulmonary TB varies and cannot provide life-long protective immunity. Based on these reasons, more efforts are channeled towards the development of new TB vaccines. During the development of TB vaccines, a major challenge has always been the lack of diversity in both the antigens contained in TB vaccines and the immune responses of the TB sufferers. Current efforts are channeled on widening both the range of antigens selection and the range of immune response elicited by the vaccines. The past two decades witnessed a significant progress in the development of TB vaccines; some of the discovered TB vaccines have recently even completed the third phase (phase III) of a clinical trial.

OBJECTIVE

The objectives of this article are to discuss the recent progress in the development of new vaccines against TB; to provide an insight on the mechanism of vaccine-mediated specific immune response stimulation, and to debate on the interaction between vaccines and global interventions to end TB.

Towards tuberculosis elimination: an action framework for low-incidence countries

This paper describes an action framework for countries with low tuberculosis (TB) incidence (<100 TB cases per million population) that are striving for TB elimination. The framework sets out priority interventions required for these countries to progress first towards "pre-elimination" (<10 cases per million) and eventually the elimination of TB as a public health problem (less than one case per million). TB epidemiology in most low-incidence countries is characterised by a low rate of transmission in the general population, occasional outbreaks, a majority of TB cases generated from progression of latent TB infection (LTBI) rather than local transmission, concentration to certain vulnerable and hard-to-reach risk groups, and challenges posed by cross-border migration. Common health system challenges are that political commitment, funding, clinical expertise and general awareness of TB diminishes as TB incidence falls. The framework presents a tailored response to these challenges, grouped into eight priority action areas: 1) ensure political commitment, funding and stewardship for planning and essential services; 2) address the most vulnerable and hard-to-reach groups; 3) address special needs of migrants and cross-border issues; 4) undertake screening for active TB and LTBI in TB contacts and selected high-risk groups, and provide appropriate treatment; 5) optimise the prevention and care of drug-resistant TB; 6) ensure continued surveillance, programme monitoring and evaluation and case-based data management; 7) invest in research and new tools; and 8) support global TB prevention, care and control. The overall approach needs to be multisectorial, focusing on equitable access to high-quality diagnosis and care, and on addressing the social determinants of TB. Because of increasing globalisation and population mobility, the response needs to have both national and global dimensions.