Detection of cytomegalovirus disease by real-time quantitative PCR targeting immediate early gene (ppUL83) in different samples among post-renal-transplant recipients

Renal transplantation is a treatment option for end-stage renal disease (ESRD). Cytomegalovirus (CMV) infection was analysed among symptomatic and asymptomatic post-renal-transplant recipients (PRTRs). A total of 30 PRTRs were enrolled. DNA was extracted and quantitative real-time PCR for CMV (CMV R-Gene, France) targeting ppUL83 gene was performed on whole blood, urine and saliva. The detection rate of CMV was found to be 27% (n = 8) in different samples, including whole blood, urine and saliva. Among 30 PRTRs, 53% (n = 16) of the PRTRs did not shed virus in saliva. About 7% of CMV was detected only in saliva among PRTRs who were symptomatic.

Molecular characterization of Chikungunya virus during an outbreak in South India.

Introduction: Re-emergence of Chikungunya is a major public health problem in the southern states of India. Objectives: This study was undertaken to investigate an outbreak of Chikungunya, in June-August 2008 using PCR and determine the prevalent genotypes of Chikungunya virus (CHIKV) associated with the outbreak. Materials and Methods: Samples of blood were collected (in heparinized vacutainer tubes) from suspected patients of CHIKV infection from both Government Taluk Hospital in Kerala and a tertiary care hospital in Chennai, Tamil Nadu. A one-step RT-PCR was carried out on a block thermo-cycler targeting the E2 gene that codes for the viral envelope protein. The amplicons were verified for 305 bp size by standard agarose gel electrophoresis. The PCR products were purified, sequenced, and compared with other CHIKV strains reported from different geographical regions. A phylogenetic tree was constructed using MEGA 4. Results: Altogether 118 samples were collected from patients who presented with sudden onset of fever and/or joint pain, myalgia, and headache. CHIKV infection was confirmed by RT-PCR in 14 patients and all these cases were from Kerala. The positivity correlated with the early stage of the disease as all these patients had fever of less than seven days duration. The study isolates have been allotted the GenBank accession nos. GQ272368-GQ272381. Phylogenetic analysis of recent CHIKV isolates by partial sequencing of E2 region shows that isolates are closely related to strains from neighboring states and the African type. Conclusion: RT-PCR is a useful technique for the early detection of CHIKV infection during outbreaks. Molecular characterization of the strains indicates that majority of the strains have originated from the Central/East African strains of CHIKV.

First outbreak of Japanese encephalitis in two villages of Dharmapuri district in Tamil Nadu.

BACKGROUND & OBJECTIVES: Three cases of Japanese encephalitis (JE) were reported for the first time from two villages in Krishnagiri Health Unit district of Tamil Nadu during November 1999. Two children died and one developed neurological sequelae. A serological survey was conducted in these villages to find out the prevalence of JE antibodies among children below 15 yr of age in addition to the epidemiological investigations. METHODS: The prevalence of haemagglutination inhibiting (HI) antibodies to JE virus (JEV), West Nile virus (WNV) and dengue-2 virus (DEN-2) was detected by HI test and IgM antibody capture ELISA (MAC ELISA) was performed to determine recent infections with JE virus. Adult mosquitoes were collected in the study villages and females of Culex pseudovishnui, C. tritaeniorhynchus and C. vishnui were tested for the presence of JE viral antigen by ELISA. RESULTS: Out of 146 sera samples from children below 15 yr, the prevalence of HI antibodies to JEV, WNV and DEN-2 virus was found to be 8.9, 3.4 and 6.85 per cent respectively and three children had IgM antibodies to JEV. Of the 13 species of mosquitoes identified, C. tritaeniorhynchus (30.8%) was the most abundant species in the study villages. Two pools of female C. tritaeniorhynchus were found to be positive for JEV antigen. Fogging with 2 per cent pyrethrum and residual spray with 10 per cent cyfluthrin were effective in reducing vector density. INTERPRETATION & CONCLUSIONS: Serological investigations revealed that the JE virus was predominant in the study villages. In addition, DEN-2 and WN viruses were also prevalent. Detection of JE virus specific IgM antibodies in three specimens and the presence of JE viral antigen in 2 pools of C. tritaeniorhynchus emphasized the need for constant surveillance and monitoring so as to prevent future large outbreaks.