Current State of the Streptococcus pneumoniae Capsular Typing Problem

Diseases caused by Streptococcus pneumoniae are a serious medical and social problem for healthcare systems of all leading countries around the globe. In this regard, the relevance of their laboratory diagnostics increases, as the effectiveness of therapeutic, preventive, and anti-epidemic measures depends on it. Currently, there is no universal method of intraspecific identification of S.pneumoniae, which simultaneously possess high specificity, sensitivity, and reproducibility. For this purpose, new alternative strategies aimed at improving the quality of research are being developed. The review presents data from domestic and foreign publications (electronic search databases eLibrary.Ru, ScienceDirect, Scopus, PubMed, Springerlink) on serotyping and genotyping of S.pneumoniae; the advantages and disadvantages of the methods are analyzed. Epidemiologically significant serotypes and widespread clonal complexes of S.pneumoniae circulating on the territory of the Russian Federation have been identified. The necessity of improving new methods of intraspecific typing of the pathogen is recognized.

1. GBD 2016 Lower Respiratory Infections Collaborator. Estimates of the global, regional, and national morbidity, mortality, and etiologies of lower respiratory infections in 195 countries, 1990–2016: a systematic analysis for the Global Burden of Disease Study 2016. Lancet Infect Dis. 2018; 18: 1191–1210. doi: 10.1016/S1473-3099(18)30310-4.

2. Голоднова С.О., Фельдблюм И.В., Семериков В.В., Николенко В.В., Захарова Ю.А. Распространённость носительства Streptococcus pneumoniae среди медицинских работников и оценка эффективности вакцинопрофилактики. Эпидемиология и вакцинопрофилактика. 2014; 1 (74): 50–54. [Golodnova S.O., Feldblium I.V., Semerikov V.V., Nikolenko V.V., Zakharova Yu.A. The Prevalence of Carriage of Streptococcus pneumoniae among Medical Specialists and Evaluation of their Vaccination. Jepidemiologija i Vakcinoprofilaktika. 2014; 1 (74): 50–54. (in Russian)]

3. Таточенко В.К. Пневмококковая инфекция: современный взгляд на проблему и профилактику. Вопросы современной педиатрии. 2007; 6 (1): 85–90. [Tatochenko V.K. Pneumococcal infection: modern view on the issue and prevention. Current Pediatrics. 2007; 6 (1): 85–90. (in Russian)]

4. Брико Н.И., Цапкова Н.Н., Батыршина Л.Р., Коршунов В.А., Фельдблюм И.В., Бикмиева А.В., Субботина К.А., Филиппов О.В. Проблемы вакцинопрофилактики взрослого населения. Эпидемиология и вакцинопрофилактика. 2018; 17 (2): 4–15. https://doi.org/10.24411-2073-3046-2018-10001. [Briko N.I., Tsapkova N.N., Batyrshina L.R., Korshunov V.A., Feldblyum I.V., Bikmieva A.V. et al. Problems of vaccinal prevention in adult population. Epidemiology and Vaccinal Prevention. 2018; 17 (2): 4–15. https://doi.org/10.24411-2073-3046-2018-10001. (in Russian)]

5. Adegbola R.A., DeAntonio R., Hill P.C., Roca A., Usuf E., Hoet B. et al. (2014) Carriage of Streptococcus pneumoniae and Other Respiratory Bacterial Pathogens in Low and Lower-Middle Income Countries: A Systematic Review and Meta-Analysis. PLoS ONE. 2014; 9 (8): e103293. doi: 10.1371/journal.pone.0103293.

6. Баранов А., Намазова Л., Таточенко В. Пневмококковая инфекция и связанные с ней заболевания — серьезная проблема современного здравоохранения. Педиатрическая фармакология. 2008; 5 (1): 7–12. [Baranov A., Namazova L., Tatochenko V. Pneumococcal infection and associated diseases — a serious problem of modern health care. Pediatric Pharmacology. 2008; 5 (1): 7–12. (in Russian)]

7. Pimenta F., Moiane B., Gertz R.E., Chochua S., Snippes Vagnone P.M., Lynfield R. et al. New pneumococcal serotype 15D. J Clin Microbiol. 2021; 59: e00329-21. doi: 10.1128/JCM.00329-21.

8. Ganaie F., Saad J.S., McGee L., van Tonder A.J., Bentley S.D., Lo S.W. et al. A new pneumococcal capsule type, 10D, is the 100th serotype and has a large cps fragment from an oral streptococcus. mBio. 2020; 11: e00937–20. doi: 10.1128/mBio.00937-20.

9. Centres for desease Control and prevention. Pneumococcal disease. For Laboratorians. Available at: https://www.cdc.gov/pneumococcal/laboratorians.html Accessed June 2022.

10. Маянский Н.А., Алябьева Н.М., Лазарева А.В., Катосова Л.К. Серотиповое разнообразие и резистентность пневмококков. Вестник Российской академии медицинских наук. 2014; 7–8: 38–45. [Mayanskiy N.A., Alyabieva N.M., Lazareva A.V., Katosova L.K. Serotype Diversity and Antimicrobial Resistance of Streptococcus pneumoniae. Vestn Ross Akad Med Nauk. 2014; 7–8: 38–45. (in Russian)]

11. Reinert R.R., Paradiso P., Fritzell B. Advances in pneumococcal vaccines: The 13-valent pneumococcal conjugate vaccine received market authorization in Europe. Expert Rev Vaccines. 2010; 9: 229– 36. doi: 10.1586/ERV.10.6.

12. Geno K.A., Gilbert G.L., Song J.Y., Skovsted I.C., Klugman K.P., Jones C., Konradsen H.B., Nahm M.H. 17 June 2015. Pneumococcal capsules and their types: past, present, and future. Clin Microbiol Rev. doi: 10.1128/CMR.00024-15.

13. Vammen B. Serological variants of pneumococcus types 9 and 10. J Immunol. 1939; 37: 359–365.

14. Sørensen U.B. Typing of pneumococci by using 12 pooled antisera. J Clin Microbiol. 1993 Aug; 31 (8): 2097–100. doi: 10.1128/jcm.31.8.2097-2100.1993. PMID: 8370735; PMCID: PMC265703.

15. Lafong A.C., Crothers E. Simple latex agglutination method for typing pneumococci. J Clin Pathol. 1988; 41: 230–231. doi: 10 .1136/jcp.41.2.230.

16. Skovsted I.C. Textbook in diagnosis, serotyping, virulence factors and Enzyme-linked Immunosorbent Assay (ELISA) for measuring pneumococcal antibodies. In: typing of Streptococcus pneumoniae. 4th Ed. SSI Diagnostica A/S. 2017; 47.

17. Konradsen H.B. Validation of serotyping of Streptococcus pneumoniae in Europe. Vaccine. 2005; 23: 1368–1373. doi: 10.1016/j.vaccine.2004.09.011.

18. Porter B.D., Ortika B.D., Satzke C. Capsular Serotyping of Streptococcus pneumoniae by Latex Agglutination. J Vis Exp. 2014; 91: e51747. doi: 10.3791/51747.

19. Mudany M.A., Kikuchi K., Totsuka K., Uchiyama T. Evaluation of a new serotyping kit for Streptococcus pneumoniae. J Med Microbiol. 2003; 52 (11): 975–980. doi: 10.1099/jmm.0.05306-0.

20. Singhal A., Lalitha M.K., John T.J., Thomas K., Raghupathy P., Jacob S., Steinhoff M.C. Modified latex agglutination test for rapid detection of Streptococcus pneumoniae and Haemophilus influenzae in cerebrospinal fluid and direct serotyping of Streptococcus pneumoniae. Eur J Clin Microbiol Infect Dis. 1996 Jun; 15 (6): 472–477. doi: 10.1007/BF01691314. PMID: 8839641.

21. Sanz J.C., Culebras E., Ríos E., Rodríguez-Avial I., Wilhelmi I., Ramos B., Ordobás M., Picazo J.J. Direct serogrouping of Streptococcus pneumoniae strains in clinical samples by use of a latex agglutination test. J Clin Microbiol. 2010 Feb; 48 (2): 593–595. doi: 10.1128/JCM.01651-09. Epub 2009 Dec 9. PMID: 20007395; PMCID: PMC2815603.

22. Sheppard C.L., Harrison T.G., Smith M.D., George R.C. Development of a sensitive, multiplexed immunoassay using xMAP beads for detection of serotype-specific Streptococcus pneumoniae antigen in urine samples. J Med Microbiol. 2011 Jan; 60 (Pt 1): 49–55. doi: 10.1099/jmm.0.023150-0. Epub 2010 Sep 23. PMID: 20864547.

23. Kalina W.V., Souza V., Wu K. et al. Qualification and clinical validation of an immunodiagnostic assay for detecting 11 additional Streptococcus pneumoniae serotype-specific polysaccharides in human urine. Clin Infect Dis. 2020; 71: e430–8.

24. Isturiz R., Grant L., Gray S., Alexander-Parrish R., Jiang Q., Jodar L., Peyrani P., Ford K.D., Pride M.W., Self W.H., Counselman F., Volturo G., Ostrosky-Zeichner L., Wunderink R.G., Sherwin R., Overcash J.S., File T., Ramirez J. Expanded analysis of 20 pneumococcal serotypes associated with radiographically confirmed community-acquired pneumonia in hospitalized US adults. Clin Infect Dis. 2021 Oct 5; 73 (7): 1216–1222. doi: 10.1093/cid/ciab375. PMID: 33982098; PMCID: PMC8492118.

25. Torres A., Menéndez R., España P.P., Fernández-Villar J.A., Marimón J.M., Cilloniz C., Méndez R., Egurrola M., Botana-Rial M., Ercibengoa M., Méndez C., Cifuentes I., Gessner B.D.; CAPA Study Group. The evolution and distribution of pneumococcal serotypes in adults hospitalized with community-acquired pneumonia in Spain using a serotype-specific urinary antigen detection test: the CAPA study, 2011–2018. Clin Infect Dis. 2021 Sep 15; 73 (6): 1075–1085. doi: 10.1093/cid/ciab307. PMID: 33851220; PMCID: PMC8442776.

26. Bentley S.D., Aanensen D.M., Mavroidi A., Saunders D., Rabbinowitsch E. Collins M. et al. Genetic analysis of the capsular biosynthetic locus from all 90 pneumococcal serotypes. PLoS Genet. 2006; 2 (3): e31. doi: 10.1371/journal.pgen.0020031.

27. Pimenta F.C., Roundtree A., Soysal A. Bakir M., du Plessis M., Wolter N. et al. Sequential triplex real-time PCR assay for detecting 21 pneumococcal capsular serotypes that account for a high global disease burden. J Clin Microbiol. 2013; 51 (2): 647–652.

28. Pai R., Gertz R.E., Beall B. Sequential multiplex PCR approach for determining capsular serotypes of Streptococcus pneumoniae isolates. J Clin Microbiol. 2006; 44 (1): 124–131. doi: 10.1128/JCM.44.1.124-131.2006.

29. Centres for desease Control and prevention. Pneumococcal disease. Resources and Protocols. Available at: https://www.cdc.gov/streplab/pneumococcus/resources.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fstreplab%2Fprotocols.html Accessed June 2022.

30. Carvalho M. da G., Tondella M.L., McCaustland K., Weidlich L., McGee L., Mayer L.W., Steigerwalt A., Whaley M., Facklam R.R., Fields B., Carlone G., Ades E.W., Dagan R., Sampson J.S. Evaluation and improvement of real-time PCR assays targeting lytA, ply, and psaA genes for detection of pneumococcal DNA. J Clin Microbiol. 2007 Aug; 45 (8): 2460–2466. doi: 10.1128/JCM.02498-06. Epub 2007 May 30. PMID: 17537936; PMCID: PMC1951257.

31. Blaschke A.J. Interpreting assays for the detection of Streptococcus pneumoniae. Clin Infect Dis. 2011 May; 52 Suppl 4 (Suppl 4): S331–7. doi: 10.1093/cid/cir048. PMID: 21460292; PMCID: PMC3069982.

32. Park H.K., Lee H.J., Kim W. Real-time PCR assays for the detection and quantification of Streptococcus pneumoniae. FEMS Microbiol Lett. 2010 Sep 1; 310 (1): 48–53. doi: 10.1111/j.1574-6968.2010.02044.x.

33. Sadowy E., Hryniewicz W. Identification of Streptococcus pneumoniae and other Mitis streptococci: importance of molecular methods. Eur J Clin Microbiol Infect Dis. 2020 Dec; 39 (12): 2247–2256. doi: 10.1007/s10096-020-03991-9. Epub 2020 Jul 24. PMID: 32710352; PMCID: PMC7669753.

34. Lang A.L.S., McNeil S.A., Hatchette T.F., Elsherif M., Martin I., LeBlanc J.J. Detection and prediction of Streptococcus pneumoniae serotypes directly from nasopharyngeal swabs using PCR. J Med Microbiol. 2015 Aug; 64 (8): 836–844. doi: 10.1099/jmm.0.000097. Epub 2015 Jun 11. PMID: 26066632.

35. Tavares D.A., Handem S., Carvalho R.J., Paulo A.C., de Lencastre H., Hinds J., Sá-Leão R. Identification of Streptococcus pneumoniae by a real-time PCR assay targeting SP2020. Sci Rep. 2019 Mar 1; 9 (1): 3285. doi: 10.1038/s41598-019-39791-1. PMID: 30824850; PMCID: PMC6397248.

36. Kukla R., Bolehovska R., Radocha J., Pliskova L., Zak P., Vrbacky F., Nekvindova J., Zemlickova H. Improved laboratory diagnostics of Streptococcus pneumoniae in respiratory tract samples through qPCR. New Microbiol. 2020 Apr; 43 (2): 70–77. Epub 2020 Apr 19. PMID: 32310299.

37. Ricketson L.J., Lidder R., Thorington R., Martin I., Vanderkooi O.G., Sadarangani M., Kellner J.D. PCR and culture analysis of Streptococcus pneumoniae nasopharyngeal carriage in healthy children. Microorganisms. 2021; 9: 2116. doi: 10.3390/microorganisms9102116.

38. Velusamy S., Tran T., Mongkolrattanothai T., Walker H., McGee L., Beall B. Expanded sequential quadriplex real-time polymerase chain reaction (PCR) for identifying pneumococcal serotypes, penicillin susceptibility, and resistance markers. Diagn Microbiol Infect Dis. 2020; 97. doi: 10.1016/j.diagmicrobio.2020.115037.

39. Carvalho M., Pimenta F.C., Moura I., Roundtree A., Gertz R.E., Li Z. et al. Non-pneumococcal mitis-group streptococci confound detection of pneumococcal capsular serotype-specific loci in upper respiratory tract. PeerJ. 2013; 1: e97. doi: 10.7717/peerj.97.

40. Antonio M., Hakeem I., Sankareh K., Cheung Y.B., Adegbola R.A. Evaluation of sequential multiplex PCR for direct detection of multiple serotypes of Streptococcus pneumoniae from nasopharyngeal secretions. J Med Microbio. 2009; 58: 296–302. doi: 0.1099/jmm.0.006031-0.

41. Никитина Е. В., Цветкова И. А., Калиногорская О. С., Гостев В.В., Беланов С. С., Мохов А. С. и соавт. Серотиповый состав Streptococcus pneumoniae, циркулирующих у детей с респираторными инфекциями, оптимизация молекулярных методов оценки. Антибиотики и химиотер. 2021; 66: 11–12: 18– 24. https://doi.org/10.37489/0235-2990-2021-66-11-12-18-24. [Nikitina E.V., Tsvetkova I.A., Kalinogorskaya O.S., Gostev V.V., Belanov S.S., Mokhov A.S. et al. Serotype composition of Streptococcus pneumoniae in children with respiratory infections, optimization of molecular assessment methods. Antibiot i Khimioter. 2021; 66 (11–12): 18–24. doi: /10.37489/0235-2990-2021-66-11-12-18-24. (in Russian)]

42. Leung M.H., Bryson K., Freystatter K., Pichon B., Edwards G., Charalambous B.M. et al. Sequetyping: serotyping Streptococcus pneumoniae by a single PCR sequencing strategy. J Clin Microbiol. 2012; 50: 2419–2427.

43. Nagaraj G., Feroze G., Vandana G., Lingegowda R. Development of PCRSeqTyping — a novel molecular assay for typing of Streptococcus pneumoniae. Pneumonia. 2017; 9 (8). doi: 10.1186/s41479-017-0032-3.

44. Enright M.C., Spratt B.G. A multilocus sequence typing scheme for Streptococcus pneumoniae: identification of clones associated with serious invasive disease. Microbiology. 1998; 144: 3049–3060.

45. Elberse K.E.M., Nunes S., Sá-Leão R., van der Heide H.G.J., Schouls L.M. Multiple-locus variable number tandem repeat analysis for Streptococcus pneumoniae: Comparison with PFGE and MLST. PLoS ONE. 2011; 6 (5): e19668. doi: 10.1371/journal.pone.0019668.

46. Миронов К.О., Гапонова И.И., Корчагин В.И., Михайлова Ю.В., Шеленков А.А., Каптелова и соавт. Антигенная и генетическая характеристика штаммов Streptococcus pneumoniae, выделенных от больных инвазивными и неинвазивными пневмококковыми инфекциями, с использованием высокопроизводительного секвенирования. Журнал микробиологии, эпидемиологии и иммунобиологии. 2021; 98 (5): 512–518. doi: 10.36233/0372-9311-144. [Mironov K.O., Gaponova I.I., Korchagin V.I., Mihailova Y.V., Shelenkov A.A., Kaptelova V.V. et al. Antigenic and genetic characterization of Streptococcus pneumoniae strains isolated from patients with invasive and non-invasive pneumococcal infections by using high-throughput sequencing. Zh Mikrobiol Epidemiol Immunobiol. 2021; 98 (5): 512–518. doi: 10.36233/0372-9311-144. (in Russian)]

47. Мартынова А.В., Балабанова Л.А., Чулакова О.А., Шепарёв А.А. Молекулярно-эпидемиологический мониторинг штаммов Streptococcus pneumoniae, выделенных у пациентов пожилого возраста с внебольничными пневмониями. Современные технологии в медицине. 2014; 6 (3): 91–96. [Martynova A.V., Balabanova L.A., Chulakova O.A., Sheparyov A.A. Molecular epidemiological monitoring of Streptococcus pneumoniae strains isolated in elderly patients with common-acquired pneumoniaes. Modern Technologies in Medicine. 2014; 6 (3): 91–96. (in Russian)]

48. Савинова Т.А., Филимонова О.Ю., Грудинина С.А., Сидоренко С.В. Генетическое разнообразие пенициллинустойчивых Streptococcus pneumoniae. Журнал инфектологии. 2009;1(4): 66–71. doi: 10.22625/2072-6732-2009-1-4-66-71. [Savinova T.A., Filimonova O.Y., Grudinina S.A., Sidorenko S.V. Genetic diversity of penicillin-resistant Streptococcus pneumoniae. Journal Infectology. 2009; 1 (4): 66–71. doi: 10.22625/2072-6732-2009-1-4-66-71. (in Russian)]

49. Straume D., Stamsås G.A., Håvarstein L.S. Natural transformation and genome evolution in Streptococcus pneumoniae. Infect Genet Evol. 2015; 33: 371–380. doi: 10.1016/j.meegid.2014.10.020.

50. Straume D., Stamsås G.A., Håvarstein L.S. Natural transformation and genome evolution in Streptococcus pneumoniae. Infect Genet Evol. 2015; 33: 371–380. doi: 10.1016/j.meegid.2014.10.020.

51. Wyres K.L., Lambertsen L.M., Croucher N.J., McGee L., von Gottberg A., Liñares J. et al. Pneumococcal capsular switching: a historical perspective. J Infect Dis. 2013; 207: 439–449. doi: 10.1093/infdis/jis703.

52. Beall B.W., Gertz R.E., Hulkower R.L., Whitney C.G., Moore M.R., Brueggemann A.B. Shifting genetic structure of invasive serotype 19A pneumococci in the United States. J Infect Dis. 2011; 203: 1360–1368. doi: 10.1093/infdis/jir052.

53. Beall B., McEllistrem M.C., Gertz R.E., Wedel S., Boxrud D.J., Gonzalez A.L. et al. Pre- and postvaccination clonal compositions of invasive pneumococcal serotypes for isolates collected in the United States in 1999, 2001, and 2002. J Clin Microbiol. 2006; 44 (3): 999–1017. doi: 10.1128/JCM.44.3.999-1017.2006.

54. Kaur R., Casey J.R., Pichichero M.E. Emerging Streptococcus pneumoniae strains colonizing the nasopharynx in children after 13- valent pneumococcal conjugate vaccination in comparison to the 7-valent era, 2006–2015. Pediatr Infect Dis J. 2016; 35 (8): 901–906. doi: 10.1097/INF.0000000000001206.

55. Миронов К.О., Корчагин В.И., Михайлова Ю.В., Янушевич Ю.Г., Шеленков А.А., Чагарян А.Н. и соавт. Характеристика штаммов Streptococcus рneumoniae, выделенных от больных инвазивными пневмококковыми инфекциями, с использованием высокопроизводительного секвенирования. Журнал микробиологии, эпидемиологии и иммунобиологии. 2020; 97 (2): 113–118. doi: 10.36233/0372-9311-2020-97-2-113-118. [Mironov K.O., Korchagin V.I., Mikhailova Y.V., Yanushevich Y.G., Shelenkov A.A., Chagaryan A.N. et al. Characterization of Streptococcus pneumoniae strains causing invasive infections using whole-genome sequencing. Zh Mikrobiol Epidemiol Immunobiol. 2020; 97 (2): 113–118. doi: 10.36233/0372-9311-2020-97-2-113-118. (in Russian)]

56. Coffey T.J., Enright M.C., Daniels M., Morona J.K., Morona R., Hryniewicz W. et al. Recombinational exchanges at the capsular polysaccharide biosynthetic locus lead to frequent serotype changes among natural isolates of Streptococcus pneumoniae. Mol Microbiol. 1998; 27 (1): 73–83. doi: 10.1046/j.1365-2958.1998.00658.x.

57. Цветкова И.А., Беланов С.С., Гостев В.В., Калиногорская О.С., Волкова М.О., Мохов А.С. и соавт. Клональная структура популяции изолятов Streptococcus pneumoniae, циркулирующих в России с 1980 по 2017 гг. Антибиотики и химиотер. 2019; 64 (5–6): 22–31. doi: 10.24411/0235-2990-2019-100027. [Tsvetkova I.A., Belanov S.S., Gostev V.V., Kalinogorskaya O.S., Volkova M.O., Mokhov A.S. et al. Clonality of Streptococcus pneumoniae isolates in Russia, circulating from 1980 to 2017. Antibiot i Khimioter. 2019; 64 (5–6): 22–31. doi: 10.24411/0235-2990-2019-100027. (in Russian)]

58. Белошицкий Г.В., Королева И.С., Миронов К.О. Фенотипическая и генотипическая характеристика штаммов пневмококков, выделенных от больных пневмококковым менингитом. Клиническая микробиология и антимикробная химиотерапия. 2011;13 (3): 261–266. [Beloshitskiy G.V., Korolyova I.S., Mironov K.O. Phenotypic and genotypic characteristics of pneumococci isolated from patients with pneumococcal meningitis. Kliniceskaia Mikrobiologia i Antimikrobnia Khimioterapia. 2011; 13 (3): 261–266. (in Russian)]

59. Белошицкий Г.В., Королева И.С., Королева М.А. Серотиповой пейзаж пневмококков, выделенных при пневмококковом менингите, в Российской Федерации. Эпидемиология и вакцинопрофилактика. 2015; 14 (2): 19–25. doi: 10.31631/2073-3046-2015-14-2-19-25. [Beloshitsky G.V., Koroleva I.S., Koroleva M.A. Landscape of serotypes pneumococcus isolate with pneumococcal meningitis in the Russian Federation. Epidemiology and Vaccinal Prevention. 2015; 14 (2): 19–25. doi: 10.31631/2073-3046-2015-14-2-19-25. (in Russian)]

60. Фельдблюм И.В., Семериков В.В., Голоднова С.О., Николенко В.В., Захарова Ю.А., Воробьева Н.Н. Результаты серотипирования штаммов Str. Pneumoniae, циркулирующих на территории г. Перми. Здоровье семьи —21 век. 2013; 2 (2): 194–203. [Feldblum I.V., Semerikov V.V., Golodnova S.O., Nikolenko V.V., Zakharova Yu.A., Vorobyeva N.N. Results of serotyping of Str. Pneumoniae strains circulating in Perm. Zdorov'e sem'i — 21 vek. 2013; 2 (2): 194–203. (in Russian)]

61. Козлов Р.С., Сивая О.В., Кречикова О.И. Динамика резистентности Streptococcus pneumoniae к антибиотикам в России за период 1999–2009: Результаты многоцентрового проспективного исследования ПеГАС. Клиническая микробиология и антимикробная химиотерапия. 2010; 12 (4): 329–341. [Kozlov R.S., Sivaya O.V., Krechikova O.I., Ivanchik N.V., Study Group «PEHASus». Antimicrobial Resistance of Streptococcus pneumoniae in Russia over the 1999–2009: Results of multicenter prospective study PEHASus. Clinical Microbiology and Antimicrobial Chemotherapy. 2010; 12 (4): 329–341. (in Russian)]

62. Sidorenko S., Rennert W., Lobzin Y., Briko N., Kozlov R., Namazova-Baranova L. et al. Multicenter study of serotype distribution of Streptococcus pneumoniae nasopharyngeal isolates from healthy children in the Russian Federation after introduction of PCV13 into the National Vaccination Calendar. Diagn Microbiol Infect Dis. 2020; 96: 1–6. doi: 10.1016/j.diagmicrobio.2019.114914.

63. Харит С., Сидоренко С., Рулева А., Перова А., Волкова М., Гостев В. и др. Распространённость пневмококковых пневмоний и отитов у детей младшего возраста (предварительные данные). Вопросы современной педиатрии. 2011; 10 (6): 103–107. [Kharit S., Sidorenko S., Ruleva A., Perova A., Volkova M., Gostev V. et al. Prevalence of pneumococcal pneumoniae and otitides in infants (provisional data). Current Pediatrics. 2011; 10 (6): 103–107. (in Russian)]

64. Garcia-Garcia S., Perez-Arguello A., Henares D., Timoneda N., MuñozAlmagro C. Rapid identification, capsular typing and molecular characterization of Streptococcus pneumoniae by using whole genome nanopore sequencing. BMC Microbiol. 2020; 20: 347. doi: 10.1186/s12866-020-02032-x.