Tuberculosis (TB) remains a major health problem in Iraq but the strains responsible for the epidemic have been poorly characterized. Our aim was to characterize the TB strains circulating in Bagdad (Iraq). A total of 270
Tuberculosis (TB) is an ancient disease that currently represents an immense global health challenge. In 2011, WHO estimated that globally there were 8.7 million new cases of active TB leading to 1.4 million reported deaths [
According to the 2012 report of the Ministry of Health (MOH), the incidence rate of TB in Iraq was 45/100,000, with 13,860 new TB cases and 1140 of previously treated cases. The Iraqi laboratory network includes 124 district smear microscopy laboratories and one national reference laboratory located in Baghdad performing cultures and drug susceptibility testing of
In the last decades, a large number of different molecular methods based on DNA fingerprints have been developed. The usefulness of these methods has been demonstrated primarily as epidemiological markers to discriminate the pathogen at the genus, species, and subspecies level. The level of strain differentiation is of crucial importance for the study of transmission dynamics, determining whether the infection is caused by single strain or by multiple strain and if recurrence of the disease is due to treatment failure or infection with new strain of
Although TB is still a public health problem in Iraq, there is little information about the genetic characteristics of the isolates driving the epidemic. A better knowledge of the molecular characteristics of
This study was conducted in Baghdad at the Center of Chest and Respiratory diseases. A total of 270 isolates were collected between 2010 and 2011 representing approximately 40% of new and previously treated TB patients. This study was approved by the local ethical committee.
Diagnostic specimens were cultured and isolated on Lowenstein-Jensen (LJ) media after decontamination. Drug Susceptibility Tests (DST) against first-line anti-TB drugs rifampicin (RFP), isoniazid (INH), streptomycin (SM), and ethambutol (EMB) were combined with LJ medium at the following concentrations: RFP 40
DNA was extracted from cultures by the standard Cetyltrimethyl ammonium-bromide (CTAB) method. The DNA was stored in TE buffer (10 mM Tris, 1 mM EDTA) at −20°C until use [
All genotyping methods were performed at the Emerging Bacterial Pathogens Unit, WHO/IUATLD Supra-National Reference TB Laboratory, San Raffaele Scientific Institute (FCSR). Spoligotyping analysis was performed by using commercial kit (Ocimun Biosolutions) as described by Kamerbeek et al. [
Standardized 24-loci MIRU-VNTR typing [
Spoligotypes in binary format and MIRU patterns in 24-digit codes were entered in the SITVIT2 database. At the time of the comparison, it contained genotyping data on more than 100,000 MTBC strains isolated from 160 countries of patient origin. In this database, “SIT” (Spoligotype International Type) designates spoligotyping shared by two or more patient isolates, “MIT” (MIRU International Type) designates 24-loci MIRU patterns shared by two or more patient isolates, and “orphan” designates patterns reported for a single isolate. Major spoligotyping-based phylogenetic clades were assigned according to revised signatures provided in SITVITWEB [
The evolutionary relationships among all the observed spoligotypes were studied by drawing minimum spanning trees (MSTs) with BioNumerics Software version 6.6 (Applied Maths, Sint-Martens-Latem, Belgium).
This study was performed over a period of 13 months on 270
Demographic characteristics of the population studied and drug resistance profiles.
Parameters | Origin of patients | ||
---|---|---|---|
Baghdad (%) | Other governorates (%) | Total | |
Total no. of strain | 157 (58.1) | 113 (41.9) | 270 |
Sex | |||
Male | 94 ( 59.9) | 85 (75.2) | 179 |
Female | 63 (40.1) | 28 (24.8) | 91 |
Sex ratio M : F | 1.49 | 3.04 | 1.97 |
Age group (yr) (no.) | |||
0–20 | 17 (10.8) | 4 (3.5) | 21 |
21–40 | 82 (52.2) | 71 (62.8) | 153 |
41–60 | 48 (30.6) | 25 (22.1) | 73 |
>60 | 10 (6.4) | 13 (11.5) | 23 |
Smear microscopy (no.) | |||
Positive | 98 (62.4) | 69 (61.1) | 167 (61.8) |
Negative | 59 (37.6) | 44 (38.9) | 103 (38.2) |
Treatment | |||
New cases | 119 (75.8) | 68 (60.2) | 187 (69.3) |
P.T.C | 38 ( 24.2) | 45 (39.8) | 83 (30.7) |
Drug susceptibility | |||
Susceptible to all drugs | 102 (65) | 69 (61.1) | 171 (63.3) |
MDR (INH − RIF) | 31 (19.8) | 33 (29.2) | 64 (23.7) |
Unknown | 24 (15.3) | 11 (9.7) | 35 (13.0) |
Spoligotyping results are summarized in Tables
Orphan strains (
Iso number | Year | Strain | Spoligotype description | Octal code | Lineage* | Label | Drug R** | Isolation city | Sex/age |
---|---|---|---|---|---|---|---|---|---|
IRQ02201004351 | 2010 | 4351 |
|
677777377413771 | EAI5 | O01 | 0 | Wasit | F/60 |
IRQ02201023876 | 2010 | 3876 |
|
703767740003071 | CAS1-Delhi | O02 | 2 | Baghdad | M/29 |
IRQ02201015527 | 2010 | 5527 |
|
037727777760771 | T3 | O03 | 1 | Babil | F/29 |
IRQ02201003954 | 2010 | 3954 |
|
037657777741770 | Unknown | O04 | 0 | Baghdad | M/22 |
IRQ02201113313 | 2011 | 3313 |
|
437727777760771 | T3 | O05 | 1 | Sulaimaniya | M/35 |
IRQ02201114243 | 2011 | 4243 |
|
537637777760771 | T1 | O06 | 1 | Baghdad | F/35 |
IRQ02201014888 | 2010 | 4888 |
|
177767377400671 | Unknown | O07 | 1 | Diyala | M/33 |
IRQ02201016952 | 2010 | 6952 |
|
577777777520771 | H3 | O08 | 1 | Baghdad | M/35 |
IRQ02201017197 | 2010 | 7197 |
|
557727777400771 | Unknown | O09 | 1 | Baghdad | M/39 |
IRQ02201115282 | 2011 | 5282 |
|
757767740003171 | Unknown | O10 | 1 | Baghdad | M/35 |
IRQ02201115448 | 2011 | 5448 |
|
757777740763771 | Manu2 | O11 | 1 | Diyala | M/63 |
IRQ02201013167 | 2010 | 3167 |
|
703627400003771 | CAS | O12 | 1 | Baghdad | F/16 |
IRQ02201003924 | 2010 | 3924 |
|
703637400003771 | CAS | O13 | 0 | Baghdad | M/48 |
IRQ02201005145 | 2010 | 5145 |
|
477767607760771 | LAM1 | O14 | 0 | Najaf | F/35 |
IRQ02201004981 | 2010 | 4981 |
|
557747607740661 | LAM9 | O15 | 0 | Dhi-qar | M/37 |
IRQ02201025861 | 2010 | 5861 |
|
637737777760771 | T3 | O16 | 2 | Al-Qadisiya | M/29 |
IRQ02201026647 | 2010 | 6647 |
|
777767636760771 | T1 | O17 | 2 | Basra | F/29 |
IRQ02201015057 | 2010 | 5057 |
|
777764077760771 | T1 | O18 | 1 | Baghdad | M/47 |
IRQ02201024897b | 2010 | 4897b |
|
677767377413771 | EAI5 | O19 | 2 | Basra | M/21 |
IRQ02201024258 | 2010 | 4258 |
|
503767740003761 | CAS1-Delhi | O20 | 2 | Baghdad | M/54 |
IRQ02201014287 | 2010 | 4287 |
|
777727777420771 | H3 (Ural-1) | O21 | 1 | Dhi-qar | F/51 |
IRQ02201016432 | 2010 | 6432 |
|
775767600760771 | T1 | O22 | 1 | Baghdad | M/60 |
IRQ02201014433 | 2010 | 4433 |
|
503667700003771 | CAS | O23 | 1 | Babil | M/23 |
IRQ02201016038 | 2010 | 6038 |
|
757767637763771 | Manu2 | O24 | 1 | Baghdad | M/28 |
IRQ02201013391 | 2010 | 3391 |
|
777727777000771 | Unknown | O25 | 1 | Baghdad | M/31 |
IRQ02201113592 | 2011 | 3592 |
|
503767400001771 | CAS | O26 | 1 | Baghdad | M/21 |
IRQ02201113234 | 2011 | 3234 |
|
777767777722771 | Manu2 | O27 | 1 | Dhi-qar | M/40 |
IRQ02201004179 | 2010 | 4179 |
|
677767637563771 | Manu2 | O28 | 0 | Baghdad | M/25 |
IRQ02201016082 | 2010 | 6082 |
|
777766607760771 | LAM9 | O29 | 1 | Baghdad | F/24 |
IRQ02201103164 | 2011 | 3164 |
|
777766637760771 | X1 | O30 | 0 | Baghdad | M/24 |
IRQ02201012729 | 2010 | 2729 |
|
701767700003071 | CAS | O31 | 1 | Dhi-qar | M/65 |
IRQ02201015095 | 2010 | 5095 |
|
403767400001771 | Unknown | O32 | 1 | Najaf | M/70 |
IRQ02201014584 | 2010 | 4584 |
|
577767777520771 | H3 | O33 | 1 | Baghdad | F/18 |
IRQ02201004326 | 2010 | 4326 |
|
777767770000771 | Unknown | O34 | 0 | Baghdad | M/25 |
IRQ02201113543 | 2011 | 3543 |
|
501767740003071 | CAS | O35 | 1 | Baghdad | M/22 |
IRQ02201026360b | 2010 | 6360b |
|
577767600760771 | T1 | O36 | 2 | Basra | M/35 |
IRQ02201014885 | 2010 | 4885 |
|
577737777520771 | H3 | O37 | 1 | Baghdad | M/29 |
IRQ02201026915 | 2010 | 6915 |
|
743767740003171 | Unknown | O38 | 2 | Salah | M/37 |
IRQ02201015996 | 2010 | 5996 |
|
757767400741771 | Unknown | O39 | 1 | Baghdad | M/20 |
IRQ02201014761 | 2010 | 4761 |
|
500000000000000 | CAS | O40 | 1 | Baghdad | F/56 |
IRQ02201113275 | 2011 | 3275 |
|
703767400003071 | CAS | O41 | 1 | Salah | M/30 |
IRQ02201004309 | 2010 | 4309 |
|
503767740003000 | CAS1-Delhi | O42 | 0 | Salah | M/37 |
IRQ02201016005 | 2010 | 6005 |
|
757767777720771 | H3 | O43 | 1 | Baghdad | F/54 |
IRQ02201123429 | 2011 | 3429 |
|
501727740003071 | CAS | O44 | 2 | Baghdad | M/53 |
IRQ02201113672 | 2011 | 3672 |
|
703767740000171 | CAS | O45 | 1 | Dhi-qar | M/58 |
IRQ02201017297 | 2010 | 7297 |
|
703727740003111 | CAS1-Delhi | O46 | 1 | Kerbala | M/24 |
IRQ02201013852 | 2010 | 3852 |
|
703767740003661 | CAS1-Delhi | O47 | 1 | Baghdad | M/20 |
IRQ02201015137 | 2010 | 5137 |
|
575767737760671 | T1 | O48 | 1 | Baghdad | M/25 |
IRQ02201012104 | 2010 | 2104 |
|
757777744743771 | Unknown | O49 | 1 | Dhi-qar | M/65 |
IRQ02201013811 | 2010 | 3811 |
|
757767777743771 | Unknown | O50 | 1 | Baghdad | F/35 |
IRQ02201113484 | 2011 | 3484 |
|
577727777420771 | H4 (Ural-2) | O51 | 1 | Baghdad | F/53 |
IRQ02201112326 | 2011 | 2326 |
|
557767777743771 | Unknown | O52 | 1 | Dhi-qar | M/56 |
IRQ02201016511 | 2010 | 6511 |
|
555727604643071 | Unknown | O53 | 1 | Wasit | M/30 |
**Drug resistance (drug R) information is shown as 0, unknown; 1, non-MDR; 2, MDRTB, that is, combined resistance to INH − RIF (with or without resistance to other drugs); 3, any other resistance(s); 4, proven XDRTB, that is, resistance to INH + RIF + a fluoroquinolone + any 1 of 3 injectable 2nd-line drugs (capreomycin, kanamycin, amikacin).
Description of 64 shared types (SITs;
SIT* | Spoligotype description | Octal number | Nb in study | % in study | % in study versus database | Lineage** | Clustered versus unique patterns*** |
---|---|---|---|---|---|---|---|
4 |
|
000000007760771 | 1 | 0.37 | 0.28 | Unknown | Unique |
20 |
|
677777607760771 | 1 | 0.37 | 0.12 | LAM1 | Unique |
22 |
|
703777400001771 | 8 | 2.96 | 10.26 | CAS1-Delhi | Clustered |
25 |
|
703777740003171 | 10 | 3.7 | 1.77 | CAS1-Delhi | Clustered |
26 |
|
703777740003771 | 12 | 4.44 | 0.87 | CAS1-Delhi | Clustered |
34 |
|
776377777760771 | 1 | 0.37 | 0.12 | S | Unique |
41 |
|
777777404760771 | 1 | 0.37 | 0.21 | LAM7-TUR | Unique |
42 |
|
777777607760771 | 1 | 0.37 | 0.03 | LAM9 | Unique |
47 |
|
777777774020771 | 1 | 0.37 | 0.07 | H1 | Unique |
50 |
|
777777777720771 | 6 | 2.22 | 0.18 | H3 | Clustered |
53 |
|
777777777760771 | 5 | 1.85 | 0.08 | T1 | Clustered |
54 |
|
777777777763771 | 8 | 2.96 | 3.31 | Manu2 | Clustered |
64 |
|
777777607560771 | 1 | 0.37 | 0.28 | LAM6 | Unique |
75 |
|
777767777720771 | 6 | 2.22 | 8.7 | H3 | Clustered |
117 |
|
777767777760731 | 2 | 0.74 | 8 | T2 | Clustered |
118 |
|
777767777760771 | 6 | 2.22 | 3.9 | T1 | Clustered |
124 |
|
777777777700771 | 1 | 0.37 | 1.54 | Unknown | Unique |
127 |
|
577777777420771 | 6 | 2.22 | 3.08 | H4 (Ural-2) | Clustered |
141 |
|
703767740003771 | 9 | 3.33 | 28.13 | CAS1-Delhi | Clustered |
186 |
|
777767404760771 | 1 | 0.37 | 8.33 | LAM7-TUR | Unique |
247 |
|
703777740003471 | 3 | 1.11 | 8.11 | CAS1-Delhi | Clustered |
284 |
|
037637777760771 | 9 | 3.33 | 5.11 | T1 | Clustered |
309 |
|
703767740003171 | 17 | 6.3 | 80.95 | CAS1-Delhi | Clustered |
485 |
|
703777400003771 | 1 | 0.37 | 4 | CAS1-Delhi | Unique |
516 |
|
777777777360771 | 1 | 0.37 | 5.56 | T1 | Unique |
568 |
|
777767477760771 | 1 | 0.37 | 20 | T-H37Rv | Unique |
610 |
|
777767774020731 | 1 | 0.37 | 14.29 | H1 | Unique |
831 |
|
776367777760771 | 1 | 0.37 | 7.69 | S | Unique |
878 |
|
777776777760571 | 1 | 0.37 | 4 | X1 | Unique |
954 |
|
703677740003771 | 1 | 0.37 | 6.67 | CAS1-Delhi | Unique |
1088 |
|
777767777763771 | 4 | 1.48 | 33.33 | Manu2 | Clustered |
1144 |
|
777777600760771 | 17 | 6.3 | 41.46 | T1 | Clustered |
1198 |
|
703737740003171 | 4 | 1.48 | 10.53 | CAS1-Delhi | Clustered |
1318 |
|
577767777760771 | 2 | 0.74 | 25 | T1 | Clustered |
1470 |
|
777776607760771 | 2 | 0.74 | 10 | LAM9 | Clustered |
1547 |
|
777727777760771 | 3 | 1.11 | 27.27 | T3 | Clustered |
1630 |
|
777777601760771 | 1 | 0.37 | 16.67 | T1 | Unique |
1638 |
|
577767777763771 | 1 | 0.37 | 33.33 | Manu2 | Unique |
1655 |
|
777723777760771 | 1 | 0.37 | 2.7 | T3 | Unique |
1679 |
|
777767737760771 | 2 | 0.74 | 20 | T1 | Clustered |
1913 |
|
777767757760771 | 1 | 0.37 | 25 | T5 | Unique |
2032 |
|
037627777760771 | 1 | 0.37 | 20 | T1 | Unique |
2230 |
|
777700077760771 | 1 | 0.37 | 16.67 | Unknown | Unique |
2359 |
|
703677740003171 | 1 | 0.37 | 4.55 | CAS1-Delhi | Unique |
2686 |
|
703767740003471 | 4 | 1.48 | 66.67 | CAS1-Delhi | Clustered |
2691 |
|
037737777760771 | 1 | 0.37 | 20 | T3 | Unique |
2707 |
|
701767740003671 | 1 | 0.37 | 33.33 | CAS | Unique |
2728 |
|
577767777420771 | 3 | 1.11 | 50 | H4 (Ural-2) | Clustered |
3275* |
|
700037777760731 | 1 | 0.37 | 50 | T2 | Unique |
3346* |
|
777767600760771 | 11 | 4.07 | 100 | T1 | Clustered |
3497* |
|
703767400001771 | 8 | 2.96 | 100 | CAS | Clustered |
3708* |
|
703767740003761 | 3 | 1.11 | 100 | CAS1-Delhi | Clustered |
3789* |
|
777777740763771 | 2 | 0.74 | 66.67 | Manu2 | Clustered |
3790* |
|
777767600360771 | 4 | 1.48 | 100 | T1 | Clustered |
3791* |
|
703727740003171 | 4 | 1.48 | 100 | CAS1-Delhi | Clustered |
3792* |
|
703767640003771 | 2 | 0.74 | 66.67 | CAS1-Delhi | Clustered |
3793* |
|
557767777763771 | 1 | 0.37 | 50 | Manu2 | Unique |
3794* |
|
703767740000771 | 1 | 0.37 | 50 | CAS | Unique |
3795* |
|
277767607760771 | 1 | 0.37 | 50 | LAM1 | Unique |
3796* |
|
703767740000371 | 1 | 0.37 | 50 | CAS | Unique |
3797* |
|
777777774120771 | 1 | 0.37 | 50 | H3 | Unique |
3798* |
|
777717777760371 | 1 | 0.37 | 50 | T1 | Unique |
3799* |
|
777767614760771 | 1 | 0.37 | 50 | T1 | Unique |
3800* |
|
703767400003771 | 2 | 0.74 | 100 | CAS | Clustered |
**Lineage designations according to SITVIT2 using revised SpolDB4 rules; “unknown” designates patterns with signatures that do not belong to any of the major lineages described in the database.
***Clustered strains correspond to a similar spoligotype pattern shared by 2 or more strains “within this study,” as opposed to unique strains harboring a spoligotype pattern that does not match with another strain from this study. Unique strains matching a preexisting pattern in the SITVIT2 database are classified as SITs, whereas in case of no match, they are designated as “orphan” (see Table
Nearly 94.1% of the isolates belonged to known genotype clades. These include, in decreasing order: CAS 39.6%, ill-defined T clade 29.6%, Manu 7.4%, Haarlem 7%, Ural 4.1%, LAM 3.3%, X 0.7%, LAM7-TUR 0.7%, EAI 0.7%, S 0.7%, and unknown 5.9%. This observation on the complex diversity of
A minimum spanning tree (MST) illustrating evolutionary relationships between the
As shown in Figure
A total of 31/64 SITs containing 184 strains were clustered within this study (2 to 17 strains per cluster) while 33/64 SITs containing 33 strains were unique. For total unique strains, one should add to this number the 53 orphan strains, which brings the number of unclustered strains in this study to 86/270 or 31.85% and clustered strains to 184/270 or 68.15%. 23 clusters are shown in Table
The two largest clusters of 17 strains were composed of SIT309 (CAS1-Delhi lineage) and SIT1144 (T1 lineage).
Description of clusters containing 5 or more isolates in this study, and their worldwide distribution in the SITVIT2 database, is detailed in Table
Description of clusters containing 5 or more isolates in this study and their worldwide distribution in the SITVIT2 database.
SIT (lineage) octal number |
Number (%) in study | % in study versus database | Distribution in regions with ≥3% of a given SIT* | Distribution in countries with ≥3% of a given SIT** |
---|---|---|---|---|
|
8 (2.96) | 10.26 | ASIA-W 65.39, ASIA-S 12.82, AFRI-E 7.69, EURO-N 5.13, EURO-W 3.85 | SAU 38.46, IRQ 25.64, IRN 7.69, TZA 3.85 |
|
10 (3.7) | 1.77 | AFRI-E 26.68, ASIA-W 22.26, AFRI-N 14.84, ASIA-S 13.6, AMER-N 9.19, EURO-N 4.95, EURO-W 4.77 | ETH 25.44, SAU 16.61, SDN 12.19, USA 9.19, IND 8.66, IRQ 5.12, IRN 3.0 |
|
12 (4.44) | 0.87 | ASIA-S 54.08, AMER-N 15.81, ASIA-W 7.51, EURO-W 6.14, AFRI-E 5.13, EURO-N 4.19, EURO-S 3.61 | IND 33.0, USA 15.81, PAK 10.4, SAU 5.63, BGD 5.42, IRN 4.48, ITA 3.47, NLD 3.11, ETH 3.11 |
|
6 (2.22) | 0.18 | AMER-S 18.03, EURO-W 17.88, AMER-N 17.88, EURO-S 11.75, EURO-E 5.62, EURO-N 4.36, AFRI-N 4.33, AFRI-S 4.12, CARI 3.55, ASIA-W 3.19 | USA 17.85, BRA 7.18, FXX 7.0, AUT 6.19, ITA 5.53, ESP 5.53, PER 4.81, ZAF 4.12, CZE 3.73 |
|
5 (1.85) | 0.08 | EURO-W 16.17, AMER-N 13.93, AMER-S 12.43, EURO-S 9.72, ASIA-W 7.19, EURO-N 5.51, AFRI-S 5.13, AFRI-E 4.66, ASIA-E 4.38, AFRI-N 3.64, EURO-E 3.37, AMER-C 3.34 | USA 13.64, FXX 8.14, ITA 5.51, BRA 5.3, ZAF 5.02, TUR 3.59, AUT 3.54, CHN 3.19 |
|
8 (2.96) | 3.31 | ASIA-W 16.53, ASIA-S 15.29, ASIA-E 15.29, AFRI-N 14.88, AMER-N 8.26, AFRI-S 6.61, ASIA-N 4.13, AMER-S 3.72 | CHN 15.29, IND 14.46, EGY 14.05, USA 8.26, SAU 8.26, ZAF 6.61, IRQ 5.79, RUS 4.13 |
|
6 (2.22) | 8.7 | AMER-S 18.84, ASIA-W 15.94, EURO-W 11.59, ASIA-S 10.15, EURO-S 7.25, AMER-N 7.25, AFRI-M 7.25, AFRI-E 5.8, EURO-E 4.35, CARI 4.35, AFRI-W 4.35 | IRN 10.15, FXX 10.15, BRA 10.15, IRQ 8.7, USA 7.25, CMR 7.25, TUR 4.35, MDG 4.35, GUF 4.35, ARG 4.35 |
|
6 (2.22) | 3.9 | ASIA-W 18.83, EURO-W 17.53, AMER-S 13.64, EURO-S 9.74, ASIA-E 9.74, AMER-N 5.2, AFRI-E 5.2, EURO-E 4.55, AMER-C 4.55 | FXX 15.58, TUR 12.34, ITA 6.49, VEN 5.84, CHN 5.84, USA 5.2, MOZ 4.55, JPN 3.9, IRQ 3.9, CZE 3.9, BRA 3.9, MEX 3.25, ARG 3.25 |
|
6 (2.22) | 3.08 | ASIA-S 54.36, EURO-W 16.41, ASIA-W 11.8, EURO-N 5.64, ASIA-E 5.13 | IRN 49.23, NLD 7.69, SAU 6.15, IRQ 5.13, CHN 5.13, SWE 4.62, AUT 4.62, DEU 3.59 |
|
9 (3.33) | 28.13 | ASIA-S 37.5, ASIA-W 31.25, EURO-W 12.5, AMER-N 12.5, ASIA-SE 3.13, AFRI-E 3.13 | IND 34.38, IRQ 28.13, USA 12.5, FXX 9.38, SAU 3.13, PAK 3.13, NLD 3.13, MOZ 3.13, MMR 3.13 |
|
9 (3.33) | 5.11 | ASIA-W 42.61, EURO-E 22.73, EURO-W 15.91, EURO-N 7.39, EURO-S 3.41 | BGR 22.73, TUR 19.89, SAU 13.07, IRQ 9.09, SWE 6.25, AUT 5.68, FXX 3.41 |
|
17 (6.3) | 80.95 | ASIA-W 85.71, AFRI-M 9.52, AFRI-E 4.76 | IRQ 80.95, CAF 9.52, SAU 4.76, ETH 4.76 |
|
17 (6.3) | 41.46 | ASIA-W 90.24, AMER-N 4.88 | IRQ 90.24, USA 4.88 |
|
11 (4.07) | 100 | ASIA-W 100.0 | IRQ 100.0 |
|
8 (2.96) | 100 | ASIA-W 100.0 | IRQ 100.0 |
**The 3 letter country codes are according to
The MIRU-VNTR analysis detected a total of 73 MIRU patterns from 110 strains using the full 24 MIRU-VNTR locus set, including 17 clusters and 56 unique (Figure
UPGMA tree based on MIRU 24 pattern of the subset of 110 samples. Drug resistance (Drug R) information is shown as 0, unknown; 1, non-MDR; 2, MDR-TB, that is, combined resistance to INH-RIF (with or without resistance to other drugs).
Both the drug resistance patterns and the treatment status of the patients (new versus retreated cases) were studied in detail on all the 270 strains included in this study in function of their spoligotyping-based genotypic lineages, and the results were concomitantly exploited to draw a minimum spanning tree (MST) shown in Figure
A minimum spanning tree (MST) illustrating evolutionary relationships between the
In this study we characterized, by spoligotyping, 270
All TB cases reported in this study were caused by
One hundred and seven (39.6%) of the 270 studied strains were CAS belonging to different SITs. CAS has also been identified as predominant family in Saudi Arabia (22.5%) and also the predominance of Delhi genogroup in Iran [
In this study 110 strains were classified into 73 MIRU patterns of which 17 were clusters and 56 unique strains. The high level of Recent Transmission Index (RTI), at 33.6%, indicates that the most cases are due to recent transmissions rather than reactivation of
MIRU-VNTR allelic results have been correlated with definition of ancestral and modern MTB lineages, with the presence of single allele in locus 24 being related to a modern strain type. We found that 98% of our strains contained only single repeat at locus 24, further confirming their modern lineage. This is comparable with previous reports for CAS strain from Bangladesh and Singapore [
This study found that in Iraqi population, the characteristic of MDR in
The data of this study provide important baseline information on the genetic diversity of
The authors declare that there is no conflict of interests regarding the publication of this paper.
Nalin Rastogi and Daniela M. Cirillo contributed equally to this paper.
Ruqaya Mustafa Ali would like to thank Baghdad University, Iraq, for funding and support.