Phylogenetic analysis of genotype 3 parvovirus B19 in Ghana, West Africa

Epidemiology

Markers

Anti-B19 IgG(%)

Anti-B19 IgM**(%)

B19 Viral DNA (%)

Viral load range (IU/mL)

BloodDonors

82

8

1.3

1.6x102-1.3x105

Children*

7.9

35

11.8

9.1x101-1.7x106

PregnantWomen

81

19

1.8

4.6x101-3.6x106

*Age range 0.13-66 months, hospitalised for severe anaemia mostly related to acute malaria (>90%).**Prevalence in viraemic B19-infected individuals.

Prevalence (%) of B19 DNA and anti-B19 IgG in 170 Ghanaian children according to age

Age groups

% p

revale

nce

0

5

10

15

20

25

30

<12m 12-23m 24-35 36-47 >48

B19 DNA Anti-B19 IgG

AJ717293

AY064476 AY064475 A

Y903437 D

Q333426

BB19

AF162273 M24682 AY386330

Z68146

M13178

DQ

408301 AY504945

AY083234

GhD3-5

GhP748

GhP693 D

Q4083

02 D

Q4083

05

DQ40

8303

DQ408304

AJ249437

GhP227 GhP416

GhD1599

GhD

28-8

0.005 substitutions/site

100

100

100

100

100

G1

G2

G3b

G3a

Phylogenetic tree of parvovirus B19 based on nearly full-length genome sequences (4866 bp)

AB030693 AB030673 M13178 Z70560 DQ408301 AY386330

Z68146 AF113323

BB19 Z70528 AY028237

Z70599 AY504945

M24682 AF162273

AB030694 AY044266

DQ333426 AY903437

AJ717293 DQ333428 AY064476 AY064475

DQ333427 DQ408305

DQ408302 AY083234

GhD3-5 GhP748 GhP693

DQ408304 DQ408303

GhP416 GhP227

GhD28-8 GhD1599

AJ249437

0.005 substitutions/site

NS1

100

100

100

100

82

G1

G2

G3b

G3a

AB030693 AB030673

M24682 Z70528 AB030694

AF162273 AF161224 AY028237

Z70560 BB19

DQ408301 Z70599

AY504945 Z68146

AF113323 AF161226

AY386330 M13178

AF161223 AF161225

AY044266 DQ333426

AY903437 DQ333428

AJ717293 AY064476

AY064475 DQ333427

DQ408305 DQ408302

DQ408304 DQ408303 AY083234

GhD3-5 GhP693

GhP748 AY647977

GhP416 GhP227

GhD28-8 GhD1599

AJ249437

0.005 substitutions/site

95

VP1u

100

99

93

G2

G3a

G1

G3b

51

100

Phylogenetic tree of parvovirus B19 based on NS1 and VP1u sequences

G3b

AB030693 AB030673

DQ408301 Z70528 AY028237

M13178 Z70560 Z68146

AF113323 AY386330

BB19 AY504945

M24682 AF162273

Z70599 AB030694

DQ408305 DQ408302

DQ408304 DQ408303 AY083234

GhP748 GhP693

GhD3-5 GhP416 GhP227

GhD28-8 GhD1599

AJ249437 DQ333427

DQ333426 AY903437

DQ333428 AY064476 AY064475

AJ717293

0.005 substitutions/site

VP2

100

100

100

100

100

G1

G2

G3a

M13178

M24682

AF162273

BB19

DQ408301

AY504945

Z70528

Z68146

AY386330

Z70560

DQ408305

DQ408302

DQ408304

DQ408303

AY083234

GhD3-5

GhP693

AY647977

GhP748

GhP416

GhP227

GhD28-8

GhD1599

AJ249437

DQ333427

DQ333426

AY903437

AY064476

AY064475

0.005 substitutions/site

100

89

90

11-kDa

90

94

G1

G2

G3a

G3b

Phylogenetic tree of parvovirus B19 based on VP2 and 11-kDa sequences

Inter-(sub)group genetic diversity based on pairwise nucleotide-substitution differences

(mean % distance [range])

Genome region

Full genome

VP2

3a vs 3b

5.42

(4.92-5.71)

6.18

(5.65-6.67)

3a vs 1

13.4

(13.2-13.7)

12.7

(12.1-13.3)

3b vs 1

13.2

(12.9-13.6)

13.0

(12.6-13.7)

3a vs 2

9.39

(9.02-9.60)

10.1

(9.49-10.8)

3b vs 2

9.32

(8.83-9.56)

10.5

(9.79-11.2)

Nucleotide-substitution rates

* Mean rate of nucleotide substitutions per site per year.† Shackelton LA & Holmes EC. 2006. J Virol 80:3666-69.HPD, 95% high-probability-density intervals; TMRCA, times from the most recent common ancestor.

Dataset

B19 genotype 3 NS1+VP1

B19 genotype 1† VP1

Mean*(HPD)

2.0x10-4

(2.0x10-6; 5.1x10-4)

1.14x10-4

(1.20x10-5; 2.40x10-4)

TMRCA

525(43.5; 1992)

-

Clock

Strict

Strict

0.001 substitutions/site

M1577P0223

AJ249437P0234 P0222 P0225 P0228 P0238 M2143 M2242

P0416 T0416

M2246 D1599 P1599 P1579 T1579 M2196

M1655 M2005 P1604 P1589 D0187 M1774

M1956 R0227 T0227 TT0227 P0496 D28-8 P0092 P1598 P0401 D0251 M1818

P1597 M1964

M1447 P0748

P0468 D0651 D3-5

M2106 AY083234P0693

P1621 P1623 AY647977 P1471

DQ408305 DQ408302

M1941 DQ408303 DQ408304

AY903437 AY044266 DQ333426

AY064476 AY064475 DQ333428

AJ717293 DQ333427 M2029

AY504945 AF161226 Z70599

AY028237 AF161224 Z70560 AF161223 AF161225 AY386330 AF113323 AF162273 AB030694 M24682 Z70528 DQ408301 Z68146 M13178 UK35834 UK720579

AB030693 AB030673 UK17932

BB19

88

75

100

73

98

G1

G2

G3b

G3a

Phylogenetic tree based on NS1/VP1u sequences of B19 genotype 3 strains from Ghana (N=53), Western Europe (N=10), and Brazil (N=7)

Conclusions

• Two genetically distinct clusters identified within B19 genotype 3 (>5% mean genetic diversity)

• Classification of genotype 3 strains into two subtypes (B19/3a and B19/3b) is proposed

• Potential West African origin of B19 genotype 3

• Similar rate of evolutionary change of B19 genotype 3 strains than those of B19 genotype 1 and carnivore parvoviruses

• High prevalence of persistent B19 genotype 3 infection (~1.4%)- no evidence of maternofetal transmission- no evidence of transfusion-transmitted infection

Acknowledgements

Dr D. CandottiNational Blood Service

Cambridge, UK

Pr J.-P. AllainDr A. Parsyan

Div. of Transfusion MedicineUniversity of Cambridge

Cambridge, UK

Dr S. Owusu-OforiMr F. Sarkodie

Transfusion Medicine UnitKomfo Anokye Teaching Hospital

Kumasi, Ghana

Dr K. DansoDr E. Addo-Yobo

Ms H. AkpeneDept. of Obstetrics & GynaecologyKomfo Anokye Teaching Hospital

Kumasi, Ghana

Mr A. DomprehDept. of Microbiology

Komfo Anokye Teaching HospitalKumasi, Ghana

Dr C. SzmaragdDept. of Genetics

University of CambridgeCambridge, UK

Dr N. EtizRefik Saydam Hygiene Centre

Dept. of VirologyAnkara, Turkey

Dr S. KerrDr G. ElliottBiotrin Ltd.

Dublin, Ireland