Interruption of the circulation of an indigenous measles genotype and the introduction of other genotypes after a mass vaccination campaign in the Philippines

Molecular analysis of measles viruses in the Philippines was conducted from 2000 to 2008. No confirmed measles cases were detected in the surveillance in 2005 after the mass vaccination campaign in 2004. However, a re-emergence of measles cases occurred in 2007, which was caused by other genotypes and the previous circulating genotype had disappeared. J. Med. Virol. 83:1424–1427, 2011. © 2011 Wiley-Liss, Inc

Enterovirus 68 among Children with Severe Acute Respiratory Infection, the Philippines

TOC summary: Enterovirus 68 was found in 21 children with severe pneumonia

Detection of human rhinovirus C viral genome in blood among children with severe respiratory infections in the Philippines.

Human rhinovirus (HRV) C was recently identified as the third species of HRV using a molecular technique. Infections caused by previously identified HRVs (A and B) are thought to be limited to the respiratory tract; however, pathogenesis of HRVC is still largely unknown. A total of 816 nasopharyngeal swabs from hospitalized children with severe respiratory infections in the Philippines (May 2008-May 2009) were tested for HRV by reverse transcription polymerase chain reaction (RT-PCR), and 243 samples (29.8%) were positive for HRV. Among these patients, serum samples were also tested to determine whether specific HRV species were associated with viremia. Only 30 serum samples (12.3%) were positive for HRV. However, the HRV positive rates were different among HRV species, 3% (4/135) for HRVA, 0% (0/25) for HRVB, and 31% (26/83) for HRVC, and were the highest on 2 days after the onset of symptoms. These results suggest that HRVC may have a different pathogenicity and can more commonly cause viremia than HRVA and HRVB. Serum positive rates for HRV are affected by age, i.e., higher positive rates for those aged 1 year or more. HRVC that were detected from serum exhibited the same level of sequence diversity as those positive only for nasopharyngeal samples in phylogenetic analysis. However, all HRVA which were detected from serum were clustered in a monophyletic clade based on their 5' non-coding region (NCR) sequences, which is closely related with a certain HRVC genotype (A2) in 5'-NCR. This finding suggests that the 5'NCR region may be associated with viremia

Phylogenetic tree of VP4-VP2.

<p>Black open circle indicates the HRVs detected only from nasopharyngeal swab samples. Red circle indicates the HRVs detected from both nasopharyngeal swab and serum samples. Phylogeny was inferred using NJ method on MEGA 4.1.</p

HRV RNA positivity in sera among patients positive for HRV in nasopharyngeal samples.

<p>First serum samples were collected on the day of admission (S-1). Second serum samples were collected 3 days after admission (S-2). OR is the odds ratio calculated with each species and the rest of the groups as the point of reference.</p><p>*p<0.01,</p><p>**p = 0.05.</p

HRV RNA positivity in sera by age group.

<p>OR is odds ratio calculated with each age groups and the rest of the groups within specie as the point of reference.</p