Dataset Information

Co-occurrence of bacteria and viruses and serotype distribution of Streptococcus pneumoniae in the nasopharynx of Tanzanian children below 2 years of age following introduction of the PCV13.

ABSTRACT:

Introduction

Pneumococcal conjugate vaccines have reduced severe disease attributed to vaccine-type pneumococci in children. However, the effect is dependent on serotype distribution in the population and disease development may be influenced by co-occurrence of viral and bacterial pathogens in the nasopharynx.

Methods

Following introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) in Tanzania we performed repeated cross-sectional surveys, including 775 children below 2 years of age attending primary healthcare centers. All children were sampled from nasopharynx and pneumococci were detected by single-target PCR. Pneumococcal serotypes/groups and presence of viruses and other bacteria were determined by two multiplex PCR assays.

Results

The prevalence of PCV13 vaccine-type pneumococci decreased by 50%, but residual vaccine-types were still detected in 21% of the children 2 years after PCV13 introduction. An increase in the non-vaccine-type 15 BC was observed. Pneumococci were often co-occurring with Haemophilus influenzae, and detection of rhino/enterovirus was associated with higher pneumococcal load.

Discussion

We conclude that presence of residual vaccine-type and emerging non-vaccine-type pneumococci in Tanzanian children demand continued pneumococcal surveillance. High co-occurrence of viral and bacterial pathogens may contribute to the disease burden and indicate the need of multiple public health interventions to improve child health in Tanzania.

SUBMITTER: Emgard M

PROVIDER: S-EPMC10839969 | biostudies-literature | 2024

REPOSITORIES: biostudies-literature

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Publications

Co-occurrence of bacteria and viruses and serotype distribution of <i>Streptococcus pneumoniae</i> in the nasopharynx of Tanzanian children below 2 years of age following introduction of the PCV13.

Emgård Matilda M Andersson Maria M Gonzales-Siles Lucia L Msuya Sia E SE Nyombi Balthazar M BM Nordén Rickard R Muro Florida F Lindh Magnus M Andersson Rune R Skovbjerg Susann S

Frontiers in public health 20240122

<h4>Introduction</h4>Pneumococcal conjugate vaccines have reduced severe disease attributed to vaccine-type pneumococci in children. However, the effect is dependent on serotype distribution in the population and disease development may be influenced by co-occurrence of viral and bacterial pathogens in the nasopharynx.<h4>Methods</h4>Following introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) in Tanzania we performed repeated cross-sectional surveys, including 775 children bel ...[more]

PMID: 38317802

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