Tuberculosis among refugees and migrant populations: Systematic review

Prevalence of pulmonary tuberculosis among key and vulnerable populations in hotspot settings of Ethiopia. A systematic review and meta-analysis

BACKGROUND

Despite the decline in tuberculosis (TB) incidence across many regions worldwide, including Ethiopia, the disease remains highly concentrated among vulnerable or socially marginalized populations and in high-risk settings. This systematic review and meta-analysis aims to estimate the pooled prevalence of pulmonary tuberculosis (PTB) among key and vulnerable populations (KVPs) residing in hotspot settings in Ethiopia.

METHODS

Potential papers were searched systematically in PubMed, Scopus, ScienceDirect databases, Google Scholar search engine, and institutional electronic repositories/registrars. A total of 34 potential articles that provide necessary information on the prevalence of PTB were reviewed and data were analyzed to determine the pooled prevalence of PTB among KVPs. The relevant data were recorded and analyzed using STATA 17.0. Cohen's kappa was computed to determine the agreement between reviewers, the Inverse of variance (I2) to evaluate heterogeneity across studies, and Egger's test to identify publication bias. A random effect model was used to determine the pooled prevalence of PTB, subgroup analysis was computed by types of hotspot settings and year of publication.

RESULTS

This meta-analysis demonstrates that the pooled prevalence of PTB among populations residing in hotspot settings in Ethiopia was 11.7% (95% confidence interval (95CI): 7.97-15.43) with an I2 of 99.91% and a p< 0.001. Furthermore, the subgroup analysis unveiled the pooled prevalence of PTB among KVPs residing in different hotspot settings as follows: Prison inmates 8.8% (95CI: 5.00-12.55%), University students 23.1% (95CI: 15.81-30.37%), Refugees 28.4% (95CI: -1.27-58.15%), Homeless peoples 5.8% (95CI: -0.67-12.35%), Healthcare settings 11.1% (95CI: 0.58-21.63%), Spiritual holy water sites attendees 12.3% (95CI: -6.26-30.80%), and other high-risk settings 4.3% (95CI: 0.47-8.09%). Besides, the subgroup analysis revealed that the pooled prevalence of PTB post-2015 was 10.79% (95CI: 5.94-15.64%), whereas it stood at 14.04% (95CI: 10.27-17.82%) before 2015.

CONCLUSION

The prevalence of PTB among KVPs residing in the hotspot settings in Ethiopia remains significant, with a weighted pooled prevalence of 11.7%. Thus, the national TB control programs should give due attention and appropriate control measures should be instituted that include regular systematic TB screening, compulsory TB testing for presumptive TB cases among KVPs, and tightened infection control at hotspot settings.

Impact of migrants on communicable diseases in Thailand

BACKGROUND

While foreign migrants contribute to economic development, they may impact public health by transmitting communicable diseases to the local population. With its geopolitical position, Thailand has been a primary destination for migrants from neighbouring countries in Southeast Asia and beyond. This positioning makes it a focal point for examining the complexities of migration dynamics and its implications for public health. Through a quantitative analysis, this paper investigates the influence of foreign migrants on physical health issues in Thailand, exploring their impact on various types of communicable diseases. The utilization of provincial-level data from Thailand offers insights into the localized effects of migrant populations on public health within the country. These insights can serve as a valuable resource for researchers and policymakers who conduct comparative analyses, facilitating a deeper understanding of the complex relationship between international migration and public health worldwide.

METHODS

A spatial panel autoregressive model (SAR) is applied on the provincial level communicable diseases and socio-economic data in Thailand from the period 2016 to 2021.

RESULTS

The results indicate that the influence of foreign migrants on communicable diseases in Thailand varies depending on the type of disease. While an increase in migrants correlates with a higher prevalence of respiratory and other communicable diseases, it conversely reduces the prevalence of vaccine-preventable diseases. Additionally, we found that migrants do not significantly impact the prevalence of food- and water-borne diseases, insect-borne diseases, animal-borne diseases, or sexually transmitted diseases in Thailand. Additionally, other factors, such as GPP per capita, unemployment, poverty, and technology access, strongly correlate with most types of communicable diseases.

CONCLUSION

As revealed by this study, the increase in migrants leads to a rise in respiratory and other communicable diseases, as well as a decrease in vaccine-preventable diseases, which carries significant policy implications. These results urge policymakers, the Ministry of Labour, and the Ministry of Public Health to implement tailored policies and measures to enhance public health and effectively mitigate the risk of communicable diseases transmitted by migrants in the future.

Laryngeal tuberculosis in the early 21st century. Literature review of clinical, diagnostic and therapeutic data, according to SWiM guidelines

OBJECTIVES

Review of the scientific medical literature dedicated to clinical data, diagnosis and treatment for laryngeal tuberculosis published since the turn of the 21st century.

MATERIAL AND METHODS

Search of the Medline, Cochrane and Embase databases for the period 2000-2022. Selection of cohorts and case reports documenting clinical data, diagnosis and treatment for laryngeal tuberculosis.

RESULTS

In total, 119 articles were analyzed. Immunodepression, HIV infection, history of lung tuberculosis, general symptoms suggesting tuberculosis, smoking and associated laryngeal cancer were noted in 18%, 3%, 20% and 41% of cases, respectively. No pathognomonic symptoms or signs emerged. Voice impairment, of various types and severity, isolated and/or associated with other signs, was the most frequent laryngeal symptom, in 86% of cases. All laryngeal sites were involved, with numerous and various associations. Impaired laryngeal motion and tracheotomy were noted in 6% and 1% of cases, respectively. Time to diagnosis varied from less than 1month to 36months, for a median 3months, in case reports. Laryngeal tuberculosis was diagnosed bacteriologically with certainty in 28% of cases while diagnosis was based on indirect criteria and/or involvement of another site in the other 72%, with lung involvement in 54%. Treatment duration ranged from 6 to 24months (median, 6months), using 3 to 5 (median: 4) antitubercular antibiotics, with 4 used in 80% of cohorts and 77% of case reports. Overall rates of cure, death, treatment resistance, adverse events, and laryngeal sequelae were 99%, 0.5%, 0.5%, 6% and 5%, respectively.

CONCLUSION

The clinical presentation and diagnostic difficulty in laryngeal tuberculosis did not change since the end of the 20th century. Quadritherapy is highly effective, with a low resistance rate and few adverse effects or laryngeal sequelae.

Tuberculosis prevalence and demographic characteristics of population in Azad Jammu and Kashmir (Pakistan): A retrospective study

Tuberculosis (TB) remains a serious problem for public health and a leading cause of death after COVID-19 and superior to even HIV/AIDS. It is a social health issue and can cause stigma and economic loss as the person cannot perform professionally due to lethargy caused by disease. It is a retrospective study done on data from National TB program Muzaffarabad chapter. The details were noted on SPSS and analysis was done to find important demographic characteristics. The total number of patients was 3441; among which 48.76% were males. Most of them (81.11%) belonged to the Muzaffarabad division of Azad Jammu and Kahmir (AJK). The microbiologically or culture positive cases were 440. Rifampicin resistance was present in 147 cases, further categorized as high (n = 143), very high (n = 3), or true positive (n = 1) resistance. Muti drug resistance was found in 19 cases. The microscopy culture is more sensitive (AUC = 0.511) than MTB/RIF or serology (AUC = 0.502) according to ROC. The rate of positive smear results is not very satisfactory in the present study as it cannot detect dormant or latent cases. There is a need to establish more sensitive tests for detection of cases and more research to combat the disease.

International Migration, Refugees, and Spread of Tuberculosis in Brazil: Analysis of Clusters, Trends, and Associated Factors (2010-2021)

BACKGROUND

International migration is a global phenomenon with significant implications on the health-disease process due to exposures along transit routes and local/destination epidemiological indicators. We aimed to analyze the transmission and spread of tuberculosis among international migrants and refugees from a spatiotemporal perspective and the associated factors.

METHOD

This was an ecological study of cases of tuberculosis in international migrants in Brazil, between 2010 and 2021. Annual incidence rates were calculated and spatiotemporal scan techniques were used to identify municipalities at risk. Multiple logistic regression was used to identify factors associated with tuberculosis in international migrants.

RESULTS

A total of 4037 cases of tuberculosis were reported in Brazil in international migrants. Municipalities at risk for this event were identified using the spatiotemporal scan technique, and a cluster was identified with ITT: +52.01% and ETT: +25.60%. A higher probability of TB infection was identified in municipalities with a TB incidence rate >14.40 cases/100 inhabitants, population >11,042 inhabitants, Gini index >0.49, and illiteracy rate >13.12%. A lower probability was found in municipalities with average per capita household income >BRL 456.43.

CONCLUSIONS

It is recommended that health authorities implement monitoring and rigorous follow-up in affected areas to ensure proper diagnosis and treatment completion for international migrants, preventing disease spread to other communities.

Screening for latent tuberculosis in migrants-status quo and future challenges

OBJECTIVES

To review the evidence that migrants from tuberculosis (TB) high-incidence countries migrating to TB low-incidence countries significantly contribute to active TB cases in the counties of destination, primarily through reactivation of latent TB.

METHODS

This is a narrative review. The different screening programs in the countries of destination are reviewed either based on screening and preventive treatment of latent TB pre or more commonly - post arrival.

RESULTS

Screening can be performed using interferon-gamma release assays (IGRA) or tuberculin skin tests (TST). Preventive treatment of latent TB is using either monotherapy with isoniazid, or in combination with rifampicin or rifapentine. We discuss the ethical issues of preventive treatment in asymptomatic individuals and how these are addressed in different screening programs.

CONCLUSION

Screening migrants from TB high endemic countries to TB low endemic countries is beneficial. There is a lack of standardization and agreement on screening protocols, follow up and treatment.

Disseminated tuberculosis in a migrant child

Tuberculosis (TB) poses a major global health threat, substantially affecting children, who contribute notably to new cases and deaths. Diagnosing TB in kids is challenging due to collection issues and the paucibacillary nature of the disease. Disseminated TB, uncommon in children in low TB incidence countries, remains a significant cause of morbidity in migrant populations. We illustrate a rare case of disseminated TB in a middle-childhood boy who migrated from Angola to France, displaying chronic cough, fatigue, weight loss and persistent fever. Investigations revealed widespread TB affecting several organs (lungs, heart, bones and lymph nodes). Prompt diagnosis led to a treatment regimen of four antibiotics (isoniazid, rifampin, pyrazinamide, ethambutol) and corticosteroids, resulting in substantial improvement after 2 months. Subsequent treatment involved two antibiotics (isoniazid and rifampin) for 10 more months. This case underscores the criticality of early identification and comprehensive treatment for disseminated TB, ensuring improved outcomes and reduced risks.

The Challenges of Tuberculosis Management beyond Professional Competence: Insights from Tuberculosis Outbreaks among Ethiopian Immigrants in Israel

Controlling tuberculosis (TB) among immigrants from high-incidence countries presents a public health concern as well as a medical challenge. In this article, we investigate a TB outbreak in a community of people of Jewish descent who emigrated from Ethiopia to Israel (Israeli Ethiopians) that started in June 2022. The index case was a 20-year-old female who had recently immigrated to Israel with her family. Her pre-immigration tuberculin skin test was positive. After excluding active TB, treatment with daily isoniazid for latent TB (LTB) was started shortly after her arrival. A year later, she was diagnosed with smear-positive, culture-positive, pulmonary TB. Investigation of 83 contacts revealed five additional patients with active TB, and three of whom were members were of her household. In this article, we report the current TB outbreak, review previously published TB outbreaks involving Israeli Ethiopians, analyze the factors that triggered each of these outbreaks, and discuss the challenges that face the Israeli TB control program in an era of declining TB incidence and diminishing resources available for TB control.

Genomic transmission clusters and circulating lineages of Mycobacterium tuberculosis among refugees residing in refugee camps in Ethiopia

BACKGROUND

Understanding the transmission dynamics of Mycobacterium tuberculosis (Mtb) could benefit the design of tuberculosis (TB) prevention and control strategies for refugee populations. Whole Genome Sequencing (WGS) has not yet been used to document the Mtb transmission dynamics among refugees in Ethiopia. We applied WGS to accurately identify transmission clusters and Mtb lineages among TB cases in refugee camps in Ethiopia.

METHOD AND DESIGN

We conducted a cross-sectional study of 610 refugees in refugee camps in Ethiopia presenting with symptoms of TB. WGS data of 67 isolates was analyzed using the Maximum Accessible Genome for Mtb Analysis (MAGMA) pipeline; iTol and FigTree were used to visualize phylogenetic trees, lineages, and the presence of transmission clusters.

RESULTS

Mtb culture-positive refugees originated from South Sudan (52/67, 77.6%), Somalia (9/67, 13.4%). Eritrea (4/67, 6%), and Sudan (2/67, 3%). The majority (52, 77.6%) of the isolates belonged to Mtb lineage (L) 3, and one L9 was identified from a Somalian refugee. The vast majority (82%) of the isolates were pan-susceptible Mtb, and none were multi-drug-resistant (MDR)-TB. Based on the 5-single nucleotide polymorphisms cutoff, we identified eight potential transmission clusters containing 23.9% of the isolates. Contact investigation confirmed epidemiological links with either family or social interaction within the refugee camps or with neighboring refugee camps.

CONCLUSION

Four lineages (L1, L3, L4, and L9) were identified, with the majority of strains being L3, reflecting the Mtb L3 dominance in South Sudan, where the majority of refugees originated from. Recent transmission among refugees was relatively low (24%), likely due to the short study period. The improved understanding of the Mtb transmission dynamics using WGS in refugee camps could assist in designing effective TB control programs for refugees.

Disease burden among refugees in camps on mainland Greece, 2016-2017: a retrospective cross-sectional study

BACKGROUND

Despite the importance of baseline health data for evidence-informed decision-making, these data are rarely available for displaced populations. At the height of the European refugee crisis, most of those seeking asylum in Europe were from regions with high prevalences of communicable and non-communicable diseases. To create an epidemiologic profile for refugees in camps on mainland Greece, this study assessed the prevalence of 11 communicable and non-communicable diseases among refugees utilizing Médecins du Monde (MdM) in-camp clinics.

METHODS

The proportional morbidity of selected diseases among individuals utilizing MdM services were determined from data collected at refugee camp clinics on mainland Greece from April 2016 - July 2017. Overall and age-specific proportional morbidities were reported. Differences in disease burden among refugees from the largest sending countries - Afghanistan and Syria - were compared using proportional morbidity ratios and 95% confidence intervals. Patterns in results were compared with disease burden estimates in sending countries and with findings from comparable settings.

RESULTS

Respiratory tract infections (RTIs) were the most prevalent outcome. Among RTIs, upper RTIs were most common, with a proportional morbidity of nearly 40%; throughout the study period, over 46% of children under 18 years had at least one upper RTI consultation. Musculoskeletal conditions (3.64%), were the most prevalent non-communicable outcome, followed by hypertension (2.21%) and asthma (1.28%). Afghans were 31.68% more likely than Syrians to have a consultation for at least one condition (PR: 1.32; 95% CI: 1.25, 1.39). The proportional morbidity of RTIs was comparable to sending countries, but there was a comparatively lower burden of other conditions among refugees than literature estimates from sending countries.

CONCLUSION

Refugees utilizing MdM clinics in camps had higher burdens of communicable diseases - predominantly RTIs - relative to non-communicable diseases. Non-communicable disease burdens were comparatively lower than reported prevalences from in-country populations. These findings can be attributed to a range of considerations including differences in demographic profiles between sending countries and refugee populations and missed opportunities for utilizing clinical care. Further investment is needed to capture the health profiles of displaced populations to support evidence-informed decision-making processes in humanitarian emergency responses.

Supporting the Respiratory Health of Migrants and Refugees

Migrants and refugees are at risk of developing acute and chronic respiratory diseases at their destination countries. Yet, people from these populations are also least likely to access care within the current health care system across the world. Although biological, psychological, and social factors play a role in influencing risk of respiratory diseases among these populations, the influences from cultural differences on health behaviors cannot be ignored. Cultural differences are influential in affecting an individual's level of health literacy. Health professionals can contribute to the provision of equitable care to diverse communities through addressing issues related to linguistic and cultural differences.

Delays in Treatment Initiation and Treatment Outcomes in Patients with Tuberculosis in the Kyrgyz Republic: Are There Differences between Migrants and Non-Migrants?

Migrants are at increased risk of developing tuberculosis (TB) and have poor treatment outcomes. The National TB program (NTP) of the Kyrgyz Republic recognizes two types of migrants: internal (intra-country) and external (inter-country) migrants. This cohort study compared the characteristics, timeliness of diagnosis and treatment initiation, and treatment outcomes of TB patients (internal migrant vs. external migrant vs. non-migrant) identified during treatment in the country in 2021. The TB treatment register and treatment cards of 5114 patients (156 internal, 430 external, and 4528 non-migrants) were reviewed. Risk factors (unemployment, smoking, alcohol use, and homelessness) were higher (p-value < 0.001) in internal (84%) than in external migrants (66%) and non-migrants (43%). The median delay in seeking care post-symptom onset was longer (p-value= 0.03) in external (30 days) than in internal migrants (21 days) and non-migrants (25 days). Successful treatment outcomes for drug-sensitive TB were higher in internal (89%, p-value = 0.012) and external migrants (86%, p-value = 0.001) than in non-migrants (78%). Internal and external migrants should be separately considered with respect to TB care and monitoring under the NTP. Success rates seem to be high in migrants, but our findings may be biased, as migrants with poor healthcare access may remain undetected and untreated and have undocumented poor outcomes.

Prevalence of tuberculosis and associated factors among presumptive TB refugees residing in refugee camps in Ethiopia

BACKGROUND

Tuberculosis (TB) causes significant morbidity and mortality in refugee populations. Although Ethiopia is the third largest refugee-hosting country in Africa, there is limited published data on the prevalence and associated factors of TB in refugees. The objective of this study was to estimate the prevalence of bacteriologically confirmed pulmonary TB (PTB) and explore associated factors in presumptive TB refugees residing in refugee camps in Ethiopia.

METHODS

A facility-based cross-sectional study was conducted between February and August 2021 in refugee camps in Ethiopia. Data were collected consecutively from 610 presumptive TB refugees who attended for TB diagnosis in selected refugee camp clinics in Ethiopia. A pre-tested questionnaire was used to collect data, and sputum samples were collected from eligible study participants. The Xpert Mycobacterium tuberculosis (MTB)/Rifampicin (RIF) assay was performed on direct spot sputum samples, whereas morning sputum samples were processed and inoculated for bacteriological culture using Mycobacterium Growth Indicator Tube (MGIT) and Lowsteen Jensen (LJ) methods. The statistical software package (STATA version 14) was used for statistical analysis. A logistic regression model was used for the evaluation of the association between bacteriologically confirmed TB cases and the associated factors. Descriptive statistics were used for the expression of the results, and statistical significance was assumed at p < 0.05.

RESULTS

Out of 610 study participants, more than half were female (54.9%), and the mean age was 37.9 years (SD, 16.64). The prevalence of bacteriologically confirmed PTB cases among refugees residing in refugee camps in Ethiopia was 13.3% (95% CI, 10.7-16.2%) using the Xpert MTB/RIF assay and/or culture. MTB was detected in 12.8% (95% CI, 10.2-15.7%) of the individuals using the Xpert MTB/RIF assay, while culture positivity was observed in 11.6% (95% CI, 9.2-14.5%). The multivariable logistic regression model showed South Sudan origins (adjusted odds ratio, AOR = 7.74; 95% CI, 3.05-19.64), age group, 19-38 years old (AOR = 5.66; 95% CI, 1.86-17.28), and male sex (AOR = 2.69; 95% CI, 1.58-4.56) were significantly associated with the bacteriologically confirmed TB among refugees residing in refugee camps in Ethiopia.

CONCLUSION

The prevalence of bacteriologically confirmed PTB among presumptive TB refugees residing in refugee camps in Ethiopia was high. The national TB program should strengthen TB prevention and control activities in the refugee camps of Ethiopia. Moreover, an active TB survey program should be implemented in refugee camps in Ethiopia.

Tuberculosis-related knowledge, behaviors, stigmatizing attitude, and discrimination among refugees, migrants, and the general population in Jordan

Objective

A better understanding of tuberculosis-related knowledge, attitude, practices in the community, and other issues can help in implementing evidence-driven activities to control tuberculosis in Jordan. This study aimed to assess tuberculosis-related knowledge, attitude, and behaviors among refugees, migrants, and general population, and assess their stigmatizing and discrimination attitudes toward tuberculosis patients, social behavior toward tuberculosis, and healthcare-seeking behaviors.

Methods

A cross-sectional study was conducted among Jordanians, Syrian refugees, and migrants living in four governorates including Amman, Zarqa, Mafraq, and Irbid during the study period of June to September 2021. A structured questionnaire was developed to collect data via face-to-face interviews. Descriptive statistics, chi-square test, and general linear model procedure were used to analyze data.

Results

A total of 2302 (27.7% Jordanians, 25.7% urban refugees, 22.1% camp refugees, and 24.5% migrants) participated in this study. Of the total, 90.1% of participants reported that they have heard of tuberculosis. However, 88.9% of Jordanians, 92.8% of urban refugees, 92% of camp refugees, and 90.5% of migrants had low level of tuberculosis-related knowledge. About 62.0% of urban refugees, 54.8% of Jordanians, 43.0% of camp refugees, and 55.4% of migrants had moderate to high stigmatizing attitude toward tuberculosis patients. About 15.1% of Jordanians, 10.6% of urban refugees, 23.7% of camp refugees, and 16.1% of migrants had moderate to high level of discriminating attitude toward tuberculosis patients. Camp refugees had a significantly higher level of discriminating attitude toward tuberculosis patients than the other groups.

Conclusion

This study identified significant gaps in tuberculosis-related knowledge among the targeted groups. Moderate to high level of stigmatizing attitude was reported by a considerable proportion of the study participants. This suggests a need for public health education programs to educate people on tuberculosis causes, signs, symptoms, mode of transmission, and address related stigma, especially among the most disadvantaged and affected communities in Jordan.

Tuberculosis related barriers and facilitators among immigrants in Atlantic Canada: A qualitative study

Tuberculosis (TB) is a disease caused by the bacterium Mycobacterium tuberculosis and affects approximately one-quarter of the world's population. Immigrant populations in Canada are disproportionately affected by TB. Canada's immigration medical examinations include screening for active TB but not latent TB infection (LTBI). In LTBI, the bacterium remains dormant within the host but can reactivate and cause disease. Once active, TB can be transmitted to close contacts sharing confined spaces leading to the possibility of outbreaks in the broader community. This study aimed to 1) assess the current TB knowledge, perceived risk, and risk behaviors of immigrants in Atlantic Canada as well as 2) identify barriers and facilitators to testing and treatment of TB among this population. Three focus group discussions were conducted with a total of 14 non-Canadian born residents of New Brunswick aged 19 years and older. Data were analyzed using inductive thematic analysis. Four themes were identified from the data relating to barriers to testing and treatment of LTBI: 1) Need for education, 2) stigma, 3) fear of testing, treatment, and healthcare system, and 4) complacency. Results included reasons individuals would not receive TB testing, treatment, or seek help, as well as facilitators to testing and treatment. These findings may inform the implemention of an LTBI screening program in Atlantic Canada and more broadly across the country.

Undiagnosed and missed active pulmonary tuberculosis during mass gatherings: a prospective cross-sectional study from the Hajj pilgrimage

Mass gatherings increase the risk of infectious diseases transmission including tuberculosis (TB). The Hajj pilgrimage to Mecca, Saudi Arabia, is attended by over 2 million pilgrims many of whom are from high TB-burden countries, and has been linked to increased risk of TB acquisition among travellers. We investigated the burden of undiagnosed and missed active pulmonary TB (PTB) among Hajj pilgrims symptomatic for cough. The study was conducted among hospitalised and non-hospitalised travellers attending the Hajj pilgrimage in 2016 and 2017. Questionnaires were used to collect relevant data and sputum samples were collected from participants and processed using the Xpert MTB-RIF assay. Non-hospitalised pilgrims (n = 1510) originating from 16 high and medium TB-burden countries were enrolled. Undiagnosed, rifampicin-sensitive, active PTB was identified in 0.7%. Comorbidities (adjOR = 5.9 [95% CI = 1.2-27.8]), close contact with a TB case (adjOR = 5.9 [95% CI = 1.2-27.8]), cough in household (adjOR = 4.46 [95% CI = 1.1-19.5]), and previous TB treatment (adjOR = 10.1 [95% CI = 4.1-98.1]) were independent risk factors for TB. Of the hospitalised pilgrims (n = 304), 2.9% were positive for PTB, and 2.3% were missed, including a rifampicin-resistant case. History of TB treatment was associated with increased risk of TB (adjOR = 8.1 [95% CI = 1.3-48.7]). International mass gatherings may play an important role in the global epidemiology of TB. Preventive measures should be directed to reducing the risk of TB importation and transmission during Hajj and other similar events.