Dynamics of the occurrence of influenza in relation to seasonal variation in Chennai, Tamil Nadu: A 7 -year cumulative study

Background: Influenza viruses have emerged as virulent pathogens causing considerable burden across the world. A thorough understanding of the pattern in occurrence of influenza globally is the need of hour. The present study deals with analysis of the dynamics of Influenza virus, especially the influence of seasonal change on viral circulation and causation of epidemics/pandemics in the context of subtropical region. Methods: During the 7 year (2009–2015) study, 36670 specimens were subjected to influenza analysis. Nasopharyngeal swabs collected from suspected patients from Chennai, Tamil Nadu, were tested and typed by real-time polymerase chain reaction assay. Results: During 2009 pandemic, among influenza A positives 95.16% were Apdm09, indicating that there was a predominant circulation of Apdm09. During postpandemic period, there were waves in the occurrence of Apdm09 which indicates fall in immunity with buildup in the susceptible population. Conclusion: In Chennai, Tamil Nadu, influenza positivity started with the onset of monsoon and peaks during the postmonsoon months throughout the study period. The assessment of meteorological factors compounding influenza activity can help in raising alerts to the public health officials of impending disaster which suggests that Influenza vaccination can be initiated before monsoon months in South India.

Isolation & molecular characterization of human parainfluenza virus in Chennai, India.

Background & objectives: Human parainfluenza virus (HPIV) accounts for a significant proportion of lower respiratory tract infections in children as well as adults. This study was done to detect the presence of different subtypes of HPIV from patients having influenza like illness (ILI). Methods: Throat and nasal swabs from 232 patients with ILI who were negative for influenza viruses were tested by multiplex reverse transcription polymerase chain reaction(mRT-PCR) for the detection of human parainfluenza virus. All samples were inoculated in rhesus monkey kidney (LLC-MK2) cell line. Results: Of the 232 samples, 26(11.2%) were positive by mRT-PCR and nine (34.6%) showed cytopathic effect with syncytium formation for HPIV and all were HPIV-3 serotype, other serotypes like 1,2,4 were negative. The HPIV-3 strains (HN gene) were sequenced and analysed. Two novel mutations were identified at amino acid residues 295 and 297. Interpretation & conclusions: The mRT-PCR assay offers a rapid, sensitive and accurate diagnostic method for detection of HPIV which enables early detection and control. In our study there was a predominance of HPIV among 1-5 yr age group and the school going age group was less affected. Further studies need to be done to characterize HPIV isolated from different parts of the country.

Anesthetic Management in an Established Case of Anterior Spinal Artery Syndrome Posted for Inguinal Hernioplsty.

Anterior spinal artery syndrome (ASAS) is a rare and permanent damage, caused as a neurological complication of spinal anesthesia. In this case study, we have given account of our experience of anesthetic management of a documented case of ASAS, posted for inguinal hernioplasty. We did a thorough pre-anesthetic evaluation and found that patient had paraplegia and confi ned to bed with aspiration pneumonitis. He is a known hypertensive and on control with tablet amlodipine 5 mg/day. He was subjected to antibiotic therapy, mucolytics with respiratory physiotherapy and incentive spirometry. After preparing the patient thoroughly, patient was subjected to general anesthesia. Post-operative analgesia was provided with injection fentanyl, given with a syringe pump. Post-operative period was uneventful.

A Unique Human Rotavirus (non vaccine) G9P4 Genotype Infection in a Child with Gastroenteritis.

Group A Rotaviruses with serotypes G1-G4 and G9 are the common Rotavirus types of clinical importance. This study aimed at determining the different Rotavirus genotypes in stool sample of children below 5 years. A total of 300 children with acute gastroenteritis were tested for group specific VP6 antigen of group A Rotaviruses by Enzyme Linked Immunosorbent Assay. 47 of these samples were positive for Rotavirus antigen. Out of these, 20 positive samples were subjected to Reverse Transcriptase Polymerase Chain Reaction for genotyping. The identified genotypes were G9P8, G1P8, G2P4, G9P4 (non-vaccine genotype), G1P6, and G1 (P types not identified in 5 samples).

Dengue disease status in Chennai (2006-2008): A retrospective analysis.

Background & objectives: Dengue is one of the most important Arboviral diseases in man with outbreaks in Southeast Asia and India. We report a retrospective analysis of the dengue positivity in the referred samples for three years period (2006 to 2008) at the Department of Virology, King Institute of Preventive Medicine, Chennai, Tamil Nadu, India. Methods: Serum samples from 1593 suspected cases (968 male and 625 female) were obtained. Of the 1593 cases screened, 1204 (75.5%) were paediatric cases and 389 (24.4%) adults. The samples were subjected to MAC ELISA and IgG ELISA. Results: Of the 968 patients, 686 (43.0%) were positive, of which 579 (84.0%) were in the paediatric age group (<14 yr) and 107 (15.5%) were adults. The IgM positivity being 356 (36.7%) in males and 330 (52.8%) in females. Of the 686 positives, 113 (16.47%) were positive for both IgM and IgG denoting secondary infection. There was a noticeable increased occurrence during the cooler months and during the monsoon and post-monsoon months. Interpretation & conclusions: The dengue IgM seropositivity among the suspected cases indicates active dengue virus activity. Increase in the probable secondary infections especially in a country like ours where multiple serotypes are prevalent raises concern over probable increase in the incidence of the more serious DHF/DSS. Studies need to be done to identify circulating serotypes of dengue virus to design preventive strategies.

A rapid method to assess the coverage of the mass drug administration of diethylcarbamazine in the program to eliminate lymphatic filariasis in India.

A rapid method to assess the coverage of mass drug administration (MDA) in the program to eliminate lymphatic filariasis needs to be developed for monitoring and evaluation of the program. This study attempted to develop and test a method of rapid assessment of coverage by using the existing resources of the program. This is based on the data obtained from the randomly selected health workers and drug distributors involved in the drug distribution process and the data of a household coverage survey of the program. The MDA coverage rate obtained through the evaluation survey was highly correlated with the rates obtained from health workers and drug distributors as a rapid assessment. Thus, MDA coverages assessed through health workers and drug distributors can give a good coverage estimate. The involvement of the existing human resources of the program in this rapid method of assessing MDA coverage was cost-effective.

Lymphatic filariasis in Khurda district of Orissa, India: an epidemiological study.

A cross-sectional survey was undertaken to determine the prevalence of disease due to lymphatic filariasis in Khurda district of Orissa, India. The total disease attributable to filariasis was significantly higher in males (14.79%) than females (10.04%). However, elephantiasis is more prevalent in females, and adenolymphangitis is more prevalent in males than their counterparts. The prevalences of various forms of the disease are age dependent in both sexes. About one-seventh of men and women of higher age groups suffered from chronic debilitation forms of the disease. The study suggests that overt clinical forms of lymphatic filariasis constitute a major public health problem in the study area.

Distribution of blood pressure and influence of subcutaneous fat on systolic and diastolic levels in a tribal population.

The distribution of arterial blood pressure levels and the influence of subcutaneous fat on blood pressure are investigated among Mall, an agricultural tribe of Andhra Pradesh. Majority of Mali people exhibit optimum levels of blood pressure. The incidence of stage 1 hypertension is moderate. The mean levels of blood pressure are relatively higher among women compared to men. The regression co-efficient values indicate a positive influence of triceps and subscapular skinfold thickness on both systolic and diastolic blood pressure among Manzai Mali. The results are discussed in the light of earlier studies.

Sixth nerve palsy following dental anaesthesia.

A case of sixth nerve palsy following dental anaesthesia given for tooth extraction is reported.