Endogenous reactivation followed by exogenous re-infection with drug resistant strains, a new challenge for tuberculosis control in Saudi Arabia

Varghese, Bright; Al-Omari, Ruba; Grimshaw, Ceilidh; Al‐Hajoj, Sahal

doi:10.1016/j.tube.2012.12.001

Cited by 15 publications

(16 citation statements)

References 18 publications

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“…Thus it can be assumed that the drug resistances are not always "imported" in this province. Supportively ongoing transmission of drug resistance among immigrants was reported in recent studies [17,25]. …”

Section: Discussionmentioning

confidence: 67%

“…This evidence is likely reflecting the specific social admixing in the country. In addition, still large number of unique isolates among immigrants alone shows the possibility of reactivation of latent infection from their home country as evidenced in a recent study [25]. Combination of contact tracing and molecular analysis among high risk population will improve the management of targeted tuberculosis cases in a heterogeneous population.…”

Section: Discussionmentioning

confidence: 99%

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Tuberculosis Transmission among Immigrants and Autochthonous Populations of the Eastern Province of Saudi Arabia

et al. 2013

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BackgroundEastern province of Saudi Arabia is an industrial zone with large immigrant population and high level of tuberculosis case notification among immigrants. The impact of immigration and current trends of tuberculosis transmission among immigrants and autochthonous population in the region had not been investigated so far using molecular tools.MethodologyDuring 2009- 2011, a total of 524 Mycobacterium tuberculosis isolates were collected from the central tuberculosis reference laboratory, representing an estimated 79.2% of the culture-positive tuberculosis cases over the study period in the province. These isolates were genotyped by using 24 locus-based MIRU-VNTR typing and spoligotyping followed by first line drug susceptibility testing. The molecular clustering profiles and phylogenetic diversity of isolates were determined and compared to the geographical origins of the patients.Principle FindingsGenotyping showed an overall predominance of Delhi/CAS (29.4%), EAI (23.8%) and Ghana (13.3%) lineages, with slightly higher proportions of Delhi/CAS among autochthonous population (33.3 %) and EAI (30.9%) among immigrants. Rate of any drug resistance was 20.2% with 2.5% of multi-drug resistance. Strain cluster analysis indicated 42 clusters comprising 210 isolates, resulting in a calculated recent transmission index of 32.1%. Overall shared cluster ratio was 78.6% while 75.8% were shared between autochthonous population and immigrant population with a predominance of immigrants from South east Asia (40.7%). In contrast, cross national transmission within the immigrant population was limited (24.2%). Younger age (15-30- p value-0.043, 16-45, p value 0.030), Saudi nationality (p value-0.004) and South East Asian origin (p value-0.011) were identified as significant predisposing factors for molecular strain clustering.ConclusionsThe high proportion of molecular clusters shared among the autochthonous and immigrant populations suggests a high permeability of tuberculosis transmission between both populations in the province. These results prompt for the need to strengthen the current tuberculosis control strategies and surveillance programs.

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Section: Discussionmentioning

confidence: 67%

Section: Discussionmentioning

confidence: 99%

Tuberculosis Transmission among Immigrants and Autochthonous Populations of the Eastern Province of Saudi Arabia

et al. 2013

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“…The most striking finding was that 35.9% of the reinfection was caused by drug-resistant strains, including MDR-TB. This trend was most pronounced among the migrants from African countries [20].…”

Section: Transmission Dynamics Of Tb In Saudi Arabiamentioning

confidence: 90%

Tuberculosis in Saudi Arabia: the journey across time

Al‐Hajoj

Varghese

2015

J Infect Dev Ctries

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Saudi Arabia is the third-largest Arab country with a moderate annual burden of tuberculosis. However, tuberculosis (TB) is among several infectious diseases that have not been brought under control, despite the government's considerable efforts. This is clearly evidenced by the ongoing transmission of several imported and indigenous clades of Mycobacterium tuberculosis. In addition, the country faces the threat from rising proportions of extrapulmonary TB, non-tuberculous mycobacterial infections, and drug resistance. Furthermore, the country falls behind the global targets set by World Health Organization for the success rate of TB treatment. The country needs more population-based research studies, centralized and easily accessible clinical data registries, and centralized research and diagnostic facilities. This review focused on the trends of mycobacterial infections and on future proposals to improve TB control measures in Saudi Arabia.

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“…24,26 In addition, Varghese and others recently demonstrated a new trend of TB transmission particularly among newly diagnosed immigrant patients, which shows the possibility of reactivation of remote infection immediately followed by a reinfection with drug-resistant strains including MDR-TB. 27 These recent findings clearly justify that the chances of drug-resistant TB in Saudi Arabia is not only limited to acquired resistance but also to recent transmissions. The drug resistance pattern showed a higher rate of panresistant isolates (50.6%) which is very high compared with previous large-scale studies and an indicative factor of XDR-TB emergence.…”

Section: Discussionmentioning

confidence: 92%

First Insight Into the Fluoroquinolone and Aminoglycoside Resistance of Multidrug-Resistant Mycobacterium tuberculosis in Saudi Arabia

Varghese

Al‐Hajoj

2017

The American Society of Tropical Medicine and Hygiene

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Abstract. In Saudi Arabia, there were no nationwide screening studies conducted so far to determine the aminoglycoside and fluoroquinolone resistance among multidrug-resistant tuberculosis (MDR-TB) isolates. Therefore, as the first attempt in the country, a retrospective analysis has been conducted on a nationwide collection of 2,956 M. tuberculosis clinical isolates screened with phenotypic drug susceptibility testing to define MDR-TB. Enrolled MDR-TB isolates were subjected to second-line drug susceptibility testing, detection of mutations conferring resistance to aminoglycosides and fluoroquinolone, followed by 24-loci mycobacterial interspersed repetitive unitvariable number of tandem repeat typing and spoligotyping. Overall, 83 isolates were identified as MDR-TB, and 13 (15.7%) isolates showed resistance to second-line drugs. Moxifloxacin (low level) showed higher resistant rates (10.8%) followed by ofloxacin (7.2%), capreomycin (3.6%), kanamycin (3.6%), and amikacin (2.4%). Overall fluoroquinolone resistance was 12%, whereas aminoglycoside resistance was 7.2%. Predominant mutations conferring resistance to fluoroquinolone were found in gyrA A90V and D94G, whereas aminoglycoside resistance was observed only with rrs gene A1401G mutation. The corresponding strain lineages predominated with Indo-Oceanic and EastAfrican Indian origin. Interestingly, none of the isolates with second-line drug resistance was defined as extensively drug-resistant TB (XDR-TB). Surprisingly, many isolates (50.6%) were panresistant to first-line drugs. Saudi Arabia faces considerable burden of fluoroquinolone-and aminoglycoside-resistant MDR-TB. Higher incidence of panresistant MDR-TB reveals a threat for the emergence of XDR-TB strains in the near future.

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Endogenous reactivation followed by exogenous re-infection with drug resistant strains, a new challenge for tuberculosis control in Saudi Arabia

Cited by 15 publications

References 18 publications

Tuberculosis Transmission among Immigrants and Autochthonous Populations of the Eastern Province of Saudi Arabia

Tuberculosis Transmission among Immigrants and Autochthonous Populations of the Eastern Province of Saudi Arabia

Tuberculosis in Saudi Arabia: the journey across time

First Insight Into the Fluoroquinolone and Aminoglycoside Resistance of Multidrug-Resistant Mycobacterium tuberculosis in Saudi Arabia

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