0

50

100

150

200

250

300

350

400

2010-11 2012 2013-2016

235

140 105

150

168

81 2-5 y.o.

< 2 y.o.

16,2

12,4

6,7

4,8

3,8 3,8 3,8

2,9 2,9 2,9 2,9 2,9 2,9

0

2

4

6

8

10

12

14

16

18

24 12F 23B 3 10A 23A 7F 14 15B 19F 22F 7C 9N

70

0

70

60 60

91,2

1,5

89,7 83,8

89,7

0

20

40

60

80

100

PEN CTX ERY TET SXT

Pre-PCV13 Post-PCV13

0

10

20

30

40

50

60

70

14 6B 18C 23F 9V 19F 4 1 5 7F 19A 6A 3 Other

2010-11 Pre-PCV13 2012 2013-2016 Post-PCV13

Emergence of Multidrug Resistant Serotype 24 among Children under 2 years old with Invasive Pneumococcal Disease after the Introduction of PCV13 in Argentina Paula Gagetti1, Alejandra Menocal1, Diego Faccone1, Sofia Fossati2, Daniela Napoli2, Mabel Regueira2, Argentina Streptococcus pneumoniae Working, Group3 and Alejandra Corso1

1Servicio Antimicrobianos, 2Servicio Bacteriologia Clínica, Instituto Nacional de Enfermedades Infecciosas - ANLIS "Dr. Carlos G Malbrán", Buenos Aires, Argentina. pgagetti@anlis.gov.ar

Invasive pneumococcal disease (IPD) is a major worldwide public health problem especially in children. Since 1993 the "IPD National Surveillance Program" (SIREVA II-OPS/WHO) is conducted at the National Reference Laboratory (NRL) in Argentina. PCV13 was introduced into National Vaccination Program (NVP) in Jan 2012 for children <1 year old with 2+1 schedule and catch-up between 12-24 months. Serotype 24 was occasionally found before 2012, and emerged after the introduction of PCV13.

• 1821 Spn isolates from sterile fluids in children <6 years old were received at the NRL between Jan 2010 and Dec 2016. They came from 150 hospitals located in 23 provinces and Buenos Aires city.

• Of these, 1029 isolates (56.5%) were from children <2 years of age.

• Three periods of time were defined and compared: Pre-PCV13 (2010-2011),

Transitional (2012) and Post-PCV13 (2013-2016).

• 97.1% of ERY-R isolates carried ermB and 2.9% mefA genes.

• All the TET-R isolates carried the tetM gene.

• Non-PCV13 serotypes increased from 13.6% to 64% after PCV13 introduction, mainly associated to three serotypes: 24, 12F and 23B.

• Serotype 24 increased from 2.1% (Pre-PCV13) to 16.2% (Post-PCV13) and ranks first since 2013 to date.

• Serotype 24 Spn isolates displayed >80% of resistance to PEN, ERY, TET, DOX and SXT.

No. 1429

BACKGROUND

MATERIAL AND METHODS

OBJECTIVE To analyze the trend in S. pneumoniae (Spn) serotype 24 distribution and its associated resistance in children <2 years old between 2010 and 2016

CONCLUSIONs

PCV13-serotypes decreased significatively (p<0.05) from 86.4% (Pre-PCV13) to 33,7% (Post-PCV13) related to serotypes 14, 6A, 6B and 5.

Other: Non-PCV13-serotypes, increased significatively (p<0.05) from 13,6% (Pre-PCV13) to 64% (Post- PCV13), mainly due to the serotypes 24, 12F and 23B.

Distribution of PCV13 Serotypes by Period of Study in Children <2 years old

• Non-PCV13 24, 12F and 23B were the most frequent serotypes in 2016, and represent 35% of the isolates.

• Serotype 24 ranks first since 2013. It represents 16.2% of the current serotypes and shows high proportion of antimicrobial resistance.

• Serotypes 12F and 23B were not associated with antimicrobial resistance.

% o

f N

on

-su

sce

pti

bili

ty

PEN: penicillin, CTX: cefotaxime, ERY: erythromycin, TET: tetracycline; SXT: trimethoprim-sulfamethoxazol. PEN and CTX were interpreted by meningitis breakpoint.

RESULTS

Argentina Spn Working Group : H Pediatria “Prof.Dr. Juan P. Garrahan” Claudia Hernandez, Lidia Casimir, H. de Clinicas “ Jose de San Martin", Carlos Vay, H Gral de Agudos "Donación Francisco Santojanni« Claudia Alfonso, H Gral de Agudos "Dr. Ignacio Pirovano« Claudia Garbaz, Sanatorio Franchin Claudia Etcheves, H Gral de Agudos" Dr. Parmenio Piñero« Daniela Ballester, Flavia Amalfa, Sanatorio Trinidad Palermo Debora Stepanik, H Italiano Graciela Greco, H Alemán Liliana Fernandez Caniggia, H de Niños "Dr.Ricardo Gutierrez" Marisa Turco, Adriana Procopio, Miryam Vazquez, CEMIC Mariela Soledad Zarate, H Británico Marta Giovanakis, H Gral de Agudos "Dr. Carlos. G. Durand" Marta Flaibani, H Gral de Agudos " Dr. Cosme Argerich" Nora Gomez, FLENI Nora Orellana, H de Niños" Pedro de Elizalde" Rosana Pereda, H Gral de Agudos "Dr. Juan A. Fernandez« Sara Kaufman, H Gral de Agudos "Dalmacio Velez Sarsfield" Silvana Manganello, Sanatorio Guemes Soledad Zarate, HIGA Evita Ana Togneri, HIGA San Juan De Dios Andrea Pacha, HIGA "Dr .Jose Penna" Maria L Benvenutti, Mabel Rizzo, HIGA "Dr. Pedro Fiorito" Silvia Fernandez, HIGA "Dr. Diego Paroissien" Maria R Cervelli, HIGA "Dr. Abraham F. Piñeyro" Monica Machain, HIGA “ Luisa C de Gandulfo” Virginia Miraglia, H Municipal de Agudos "Dr. Leonidas Lucero" Laura Paniccia, HIGA "Presidente Perón" Maria Adelaida Rosetti, HIGA" Vicente Lopez y Planes" Hebe Gullo, Maria Susana Commisso, H Zonal Gral de Agudos "Dr. Carlos Bocalandro" Carolina Baccino, H Materno Infantil "Dr. Tetamanti" Victoria Monzani, Laura Morvay, H Municipal "Dr. Bernardo Houssay" Veronica Berdiñas, H Universitario “Austral” Viviana Vilches, H "Dr. Arturo Oñativia" Ana Laura Mariñazky, H Zonal Especializado de Agudos y Crónicos "Dr. Cetrangolo" Andrea Appendino, Laura Biglieri, H Zonal "Gdor. Domingo Mercante" Sandra Bognanni, H de Niños "Sor Maria Ludovica" Cecilia Vescina, H Municipal de Pediatria "Dr. Federico Abete" Cristian Corio, Liliana Esteves, H del Niño de San Justo Liliana Meccia, HIGA "Eva Peron" Marisa Almuzara, H Municipal "Dr. Enrique Sturiz" Alejandra Sale, H Municipal " Ramón Santamarina" Monica Sparo, H Municipal " Dr. Emilio Zerboni" Sofia Murzicato, H Municipal "Dr. Federico Falcon" Celina Santander, H Municipal "Ostaciana V. Lavignolle" Maricel Garrone, H Nacional" Prof. Dr. Alejandro Posadas" Adriana Fernandez Lausi, H Privado de Comunidad Monica Vallejo, H Municipal "Dr. Pedro Orellana" Cecilia Barrachia, H Zonal General de Agudos "Virgen del Carmen" Adriana Melo, HIGA "Dr. Enrique Erril" Victoria Ascua, H Zonal Materno Infantil "Argentina Diego" Ana Mola, Laboratorio central de Salud Pública Catamarca Daniela Carrizo, H Interzonal de Niños "Eva Peron" Patricia Valdez, Mariela Silvia Farfan, H Interzonal "San Juan Bautista" Viviana David, H Pediatrico "Dr. Avelino Castelan" Ana Maria Zaloff Dakoff, Viviana Isabel Saito, H "Dr Julio C Perrando” Laura Pícoli, Mariana Carol Rey, Hospital 4 de Junio "Dr. Ramon Carrillo" Norma Cech, H Regional " Dr.Victor M. Sanguinetti" Susana Ortiz, Lab.de la Direccion de Patologia Prevalente y Epidemiologia Chubut Mario Flores, H Zonal Esquel Omar Daher, H "Dr. Guillermo Rawson" Ana Littvik, H Regional " Dr. Louis Pasteur" Claudia Amareto, Clinica Privada Velez Sarsfield Lidia Wolff , H Regional "Domingo Funes" Lilia Camisassa, H Infantil Municipal de Córdoba Liliana Gonzalez, H de Niños "Santísima Trinidad" Patricia Montanaro, Clinica Universitaria "Reina Fabiola" Marina Botiglieri, H Pediatrico del Niño Jesus, Paulo Cortez, H "Angela Llano" Ana Maria Pato, Hl Pediátrico "Juan Pablo II" Celia Monzón, H Materno Infantil "San Roque" Lorena del Barco, Maria Eugenia de Torres, H "Delicia C. Masvernat" Maria Ofelia Moulins, Luis Otaegui, H de la Madre y el Niño Formosa Nancy Comello, Silvana Vivaldo, H Central Formosa Nancy Pereyra, H de Niños "Dr. Hector Quintana" Marcelo Toffoli, Gabriela Granados, Laboratorio Central de Salud Publica Jujuy María Rosa Pizarro, H "Gobernador Centeno" Adriana Pereyra, H "Dr.Lucio Molas" Gladys Almada, H Regional "Dr. Enrique Vera Barros" Sonia Flores, Monica Romanazi, H "Dr. Teodoro J Schestakow" Ada Zanusso, Adriana Acosta, H Pediátrico "Dr. Humberto Notti" Laura Balbi, Beatriz Garcia, H Público Samic El Dorado Ana Maria Miranda, H Provincial de Pediatria "Dr. Fernando Barreyro" Martha Von Spetch, H Provincial "Dr. Castro Rendon" Sandra Grenon, H Escuela de Agudos "Dr. Ramón Madariaga" Viviana Villalba, Cristina Perez, H "Dr. Horacio Heller" Fernanda Bulgueroni, H Zonal Bariloche "Dr. Ramon Carrillo" Nestor Blazquez, Maria Laura Alvarez, H Area Cipolletti Cristina Carranza, Mariela Roncallo, H "Francisco Lopez Lima" Gonzalo Crombas, H "Artémides Zatti" Maria Gabriela Rivolier, H "Presidente Peron" Cristina Bono, Eloisa Aguirre, H Publico Materno Infantil Norma Sponton, H "San Vicente de Paul" Silvia Amador, H "Marcial Quiroga" Hugo Castro, Hospital "Dr. Guillermo Rawson" Marisa Lopez, Osvaldo Navarro, Policlínico Regional "Juan Domingo Peron" Ema Maria Fernandez, Policlínico Central San Luis Hugo Rigo, H Zonal de Caleta Olivia "Pedro Tardivo" Josefina Villegas, H Regional de Rio Gallegos Wilma Krause, Mariel Borda, H de Niños "Dr. Victor J. Vilela" Andrea Badano, Adriana Ernst, Laboratorio Central de Salud Publica Santa Fe Andrea Nepote, Maria Gilli, H "Dr. Jose M. Cullen" Emilce Mendez, Alicia Nagel, CEMAR María Inés Zamboni, Julieta Valles, H Español Noemi Borda, H de Niños "Dr. Orlando Allasia" Stella Virgolini, María Rosa Baroni, H Regional "Dr. Ramon Carrillo" Ana María Nanni de Fuster, H de Niños (CePSI) "Eva Peron" Maria Elisa Pavon, H Regional Ushuaia Manuel Boutureira, H Regional Rio Grande Marcela Vargas, H del Niño Jesus Ana Maria Villagra de Trejo, Jose Assa, H de Clinicas "Presidente Dr. Nicolas Avellaneda" Norma Cudmani.

• The number of IPD cases received at the NRL decreased 55.3%, from 235 in Pre-PCV13 to 105 (annual average in <2 years old) in Post-PCV13 (Figure 1).

• Spn isolates were serotyped by Quellung.

• MIC was performed by agar dilution method (CLSI).

• Macrolide and tetracycline resistance genes were detected by PCR.

• 80/1029 (7.8%) Spn were serotype 24.

• Among 80 serotype 24 Spn, 44 (55%) were <1 year old.

• The number of serotype 24 Spn isolates by period of study were: 10 in Pre-PCV13, 2 in transitional and 68 in Post-PCV13.

Current Distribution of Main Serotypes: 2016

%

• All the isolates were susceptible to meropenem, chloramphenicol, levofloxacin, rifampicin, ceftaroline and vancomycin.

• When comparing both periods, there were an increase in PEN, ERY, TET and SXT resistance, however these differences were not statistically significant.

Multidrug resistance to PEN, ERY, TET, DOX and SXT increased from 50% in Pre-PCV13 to 82% in Post-PCV13 period.

p<0.05

Proportion of MDR Serotype 24 Isolates

% o

f is

ola

tes

PCV-7 PCV-13

PCV-10

Antimicrobial Non-susceptibility among Serotype 24 isolates: Pre versus Post-PCV13 Periods

% o

f M

DR

n: 1029

n: 139 n: 471 n: 419

Main Changes in Serotype Distribution by Period of Study

Annual Average of Spn Isolates Received at the NRL between 2010-2016 causing IPD

Distribution by clinical diagnosis in children <2 years old

MIC distribution among Serotype 24 isolates (n:80)

N: 1029

No

of

Spn

iso

late

s Genotype Distribution in Erythromycin and Tetracycline resistant Serotype 24 Isolates

Ge

no

typ

e

Phenotype

64

27

13,6

Serotypes 24 (2,1% Pre- to 16.2% Post-PCV13), 12F (3% Pre- to 9.1% Post-PCV13) and 23B (0,2% Pre- to 3.3% Post-PCV13) increased significantly in Pre- and Post-PCV13 periods.

Serotype 23B24 Serotype 2424 Serotype 12F24

PCV13 serotypes Other Non-PCV13 serotypes

2,1 1,4

16,2 3,0 4,3

9,1

0,2 1,4

3,3

8,3

19,4

37,7

86,4 73,4

33,7

0%

20%

40%

60%

80%

100%

2010-11 2012 2013-16

n: 419 n: 139 n: 471

1

2

3 4 5

6 7 8 9

• MDR to PEN, ERY, TET, DOX and SXT increased in Serotype 24 isolates from 50% (Pre-PCV13) to 82% (Post-PCV13).

• Our results suggest that this emerging serotype could represent a real threat among pneumococcal disease in the near future.

Pre-PCV13 2010-2011 2012 Pos-PCV13 2013-2016

Pre-PCV13 2010-2011 Post-PCV13 2013-2016

CIM (ug/ml) 0.008 0.015 0.03 0.06 0.12 0.25 0.5 1 4 16 % Resistance

Penicillin 89.2

Cefotaxime 1.1

Amoxicillin 0

Meropenem 0

Erythromycin 87.8

Tetracycline 81.1

Doxycycline 81.1

Trimethoprim-sulfamethoxazol 86.5

Chloramphenicol 0

Levofloxacin 0

Rifampin 0

Vancomycin 0

2 ≥328

CIM 50 CIM 90 Rango CLSI Breakpoint

0%

20%

40%

60%

80%

100%

ERY-R TET-R

2,9

97,1 100

mefA ermB tetM