Human Bocavirus genotypes 1 and 2 detected in younger Amazonian children with acute gastroenteritis or respiratory infections, respectively

Highlights

• Human Bocavirus infects children of <5 months of age from the Amazon Region with acute gastroenteritis and respiratory infections with a frequency of 14%.

• Human Bocavirus genotype 1 is mainly detected in children of <5 months of age from the Amazon Region with acute gastroenteritis.

• Human bocavirus genotype 2 is mainly detected in children of <5 months of age from the Amazon Region with acute respiratory infection.

• Human Bocavirus genotype 1 DNA and Messenger RNA detected in fecal samples but not in saliva, is evidence of intestinal tract infection occurring in children of <5 months of age with acute gastroenteritis.

Abstract

Objectives

This study aimed to verify the frequency, genotypes, and etiological role of Human Bocavirus (HBoV) in younger Amazonian children with either acute gastroenteritis (AGE) or respiratory infections (ARI). The influence of Rotarix™ vaccination and co-infection status was also investigated.

Design

HBoV quantitative polymerase chain reaction (qPCR) testing was done on both fecal and saliva (1468 samples) from 734 children < 5 months old living in the Amazon (Brazil, Guyana, and Venezuela). High and median HBoV viral load samples were used for extraction, nested PCR amplification, and sequencing for genotyping. HBoV mRNA detection was done by reverse transcription following DNA amplification.

Results

The overall HBoV frequencies were 14.2% (69/485; AGE) and 14.1% (35/249; ARI) (p = 0.83). HBoV exclusively infected 4.5% (22/485; AGE) and 4% (10/249) of the Amazonian children (Odds ratios 1.13, 95% confidence interval= 2.42-0.52). HBoV 1 was mainly detected in feces and saliva from AGE children; and HBoV2, from ARI children. HBoV mRNA was detected only in feces. The Rotarix™ vaccination status did not affect the HBoV frequencies.

Conclusions

We suggest that, after entry into the air/oral pathways, HBoV1 continues infecting toward the intestinal tract causing AGE. HBoV2 can be a causative agent of AGE and ARI in younger Amazonian children.