Viral burden and diversity in acute respiratory tract infections in hospitalized children in wet and dry zones of Sri Lanka.

The present study was done to identify the viral diversity, seasonality and burden associated with childhood acute respiratory tract infection (ARTI) in Sri Lanka. Nasopharyngeal aspirates (NPA) of hospitalized children (1 month-5 years) with ARTI were collected in 2 centers (wet and dry zones) from March 2013 to August 2014. Respiratory viral antigen detection by immunofluorescence assay (IFA) was used to identify the infecting viruses. IFA negative 100 NPA samples were tested for human metapeumovirus (hMPV), human bocavirus and corona viruses by polymerase chain reaction. Of the 443 and 418 NPAs, 37.2% and 39.4% were positive for any of the 8 different respiratory viruses tested from two centers studied. Viral co-infection was detected with respiratory syncytial virus (RSV) in both centers. Peak viral detection was noted in the wet zone from May-July 2013 and 2014 and in the dry zone from December-January 2014 suggesting a local seasonality for viral ARTI. RSV showed a clear seasonality with a direct correlation of monthly RSV infections with rainy days in the wet zone and an inverse correlation with temperature in both centers. The case fatality rate was 2.7% for RSV associated ARTI. The overall disability adjusted life years was 335.9 and for RSV associated ARTI it was 241.8. RSV was the commonly detected respiratory virus with an annual seasonality and distribution in rainy seasons in the dry and wet zones of Sri Lanka. Identifying the virus and seasonality will contribute to employ preventive measures and reduce the empirical use of antibiotics in resource limited settings.

A case series on common cold to severe bronchiolitis and pneumonia in children following human metapneumovirus infection in Sri Lanka.

OBJECTIVES: The prevalence of hMPV infections in Sri Lanka has not been reported and here we report a case series of hMPV infection in children less than 5 years. Patients with ARTI were included from Teaching Hospital, Anuradhapura from March 2013 to August 2014. Indirect fluorescence assay was performed on nasopharyngeal aspirates for the identification of respiratory viruses [respiratory syncytial virus (RSV), parainfluenza virus 1, 2 and 3, influenza A and B and hMPV]. Moreover, reverse transcriptase-polymerase chain reaction was done to further confirm the hMPV infection. RESULTS: In this case series, hMPV infection showed a range of respiratory symptoms from common cold to life threatening lower respiratory tract infections with varying severity. In some cases, the clinical presentation of hMPV infection was similar to the ARTI caused by RSV. hMPV co-infections with of RSV have also been seen in some cases of ARTI. A child delivered through cesarean section and birth order > 3 has an Odds ratio of 3.5 and 4.3 (95% CI) for developing co-infection with RSV compared to hMPV mono-infections. Lack of diagnostic facilities to identify the viral aetiology has contributed to the use of antibiotics indicating the need for establishing viral diagnostic facilities in the country.

Genotypes of hepatitis B virus identified in patients tested prior to endoscopy from a Teaching Hospital in the Central Province of Sri Lanka.

The present study was carried out to identify the hepatitis B virus (HBV) genotypes in six patients attending the surgical clinic who were positive for hepatitis B surface antigen. DNA was extracted from the serum of patients and subjected to a modified nested PCR to detect a 585 bp region within the S gene of the HBV genome. Positive PCR products were purified and sequenced via a cycle sequencing method. The sequence data were analyzed with reference sequences in the HepSEQ database to identify the particular HBV genotype of the samples. Nested PCR for the S gene of the HBV genome was positive in 2 out of 6 samples. The genotyping and sequence analysis of the PCR products showed HBV genotype A with a homology of 98% to the reference sequences in the HepSeq database.