Antigenic and Genetic Characterization of Influenza Viruses Circulating in Chennai during 2002-2007. Screening of Indegenous Herbs for Anti-Influenza Viral Activity and Sensitivity of the Isolates to Amantadine

Acute Respiratory Diseases (ARD) cause enormous morbidity and mortality, particularly in infants and children in developing countries. ARD is responsible for about 4 million deaths and 500- 900 million episodes per annum in children globally. In India, studies indicate that 600,000 children under the age of 5 die every year from ARD. There is considerable variation in the severity of illness caused by Influenza in different individuals. This is partly due to the age of those affected, general health, and immunistation status relative to previous Influenza infections. Infections may be subclinical or may produce symptoms ranging from minor respiratory illness to fatal viral pneumonia. The “classic” symptoms of Influenza are rapid onset of malaise, feverishness and myalgia, usually with a non productive cough or sore throat. In children, nausea, vomiting and diarrhea are often observed. Blood samples for serosurveillance were collected from normal healthy children attending ICDS units in Chennai and from adults for attending hospitals for reasons other than acute respiratory tract infections. 200 samples were collected during the year; 50 samples from each age group in four age groups (0-5, 6-15, 16-45, 46-60). A serosurvey for the presence of antibodies to the circulating Influenza A & B among the apparently healthy population of Chennai was done during 2001-2006. In the present study, the exposure of the population to Influenza viruses was determined by detecting the haemagglutinating IgG antibodies to the Influenza viruses in four age groups 0-5, 6-15, 16-45, and 46-60 by haemagglutination inhibition test. 50 samples from apparently healthy individuals of each age group were tested each year, 2001 to 2006.HAI test was performed as per standard WHO protocols and using WHO reagent kit supplied by Influenza branch Centres for Disease Control and Prevention, Atlanta. Serosurvey for determination of Influenza Haemagglutinating antibody base-line titre The results of the serosurvey established the baseline neutralizing antibody titre of 1:40 for Influenza in normal healthy population. Antibodies to Influenza A& B group were found to be elevated in the 6-15 years age group indicating high exposure to Influenza in indicating high circulation of Influenza A&B viruses in this age group. It is necessary to evaluate baseline titer periodically to assign the cut-off values for diagnostic purposes. It also indicates the outbreaks that might have occurred silently. Influenza virus etiology of Acute Respiratory Infections (2002-2007) Influenza accounted for 7.77% of acute respiratory infections cases from 2002-2007 and Influenza A/H1N1 among Influenza A type and B/Yamagata type among the Influenza B type were found to be the predominant serotype. Male and female children were equally affected. The notable feature that was observed in the study was the increased virus isolation during the early months of monsoon and winter. Simultaneous coexistence of Influenza A and B serotypes throughout the study period confirmed their endemic circulation. There has been a continuous variation in the Influenza strains isolated in the study period. A/H3N2 predominated in the years 2002-2004 then H1N1 that was not circulating till then came into existence and predominated in the years 2005-2006. The year 2007 saw the predominance of the Influenza B type viruses for the first time. As the virus activity is constantly changing, there is a need for continuous surveillance. CLINICAL MANIFESTATION: The symptoms in a combination of cough, headache, and pharyngitis were found to predict an increased likelihood of Influenza. SENSITIVITY TO AMANTADINE: Resistance has started to emerge among the Influenza A/H3N2 type viruses. 4 isolates in the study period showed resistance but the resistance percentage is increasing every year. The results of MIC were in total concurrence with RT-PCR RFLP, therefore MIC can be used to screen large number of samples and the positives can be subjected to RT-PCR RFLP to study where the mutations have occurred and about the amino acid change. There is a need for continued surveillance for Amantadine resistance. ANTIVIRAL SCREENING OF TWO HERBS: The results of antiviral evaluation of two herbs showed that the aqueous and ethanolic extracts of herbs Ocimum sanctum and Glycyrrhiza glabra showed anti Influenza B activity. The extracts of both were virucidal and inhibitory to viral replication. The virucidal effect of the all the three extracts were concentration dependent

Pathogenesis of influenza in the Ferret Model : a basis for improved intervention

Although clinical disease and associated lesions of the respiratory tract due to IAV infections are well known, the exact pathogenesis of acute respiratory distress syndrome (ARDS) is not yet fully understood. ARDS is a fatal complication of influenza virus infection, and accounts for many influenza-­‐related mortalities. At the starting point of this thesis, the mechanism of pulmonary oedema formation, as one of the hallmarks

Emerging infectious diseases

Emerging Infectious Diseases is providing access to these abstracts on behalf of the ICEID 2012 program committee (www.iceid.org), which performed peer review. Emerging Infectious Diseases has not edited or proofread these materials and is not responsible for inaccuracies or omissions. All information is subject to change. Comments and corrections should be brought to the attention of the authors.Influenza preparedness: lessons learned -- Policy implications and infectious diseases -- Improving preparedness for infectious diseases -- New or rapid diagnostics -- Foodborne and waterborne infections -- Effective and sustainable surveillance platforms -- Healthcare-associated infections -- Molecular epidemiology -- Antimicrobial resistance -- Tropical infections and parasitic diseases -- H1N1 influenza -- Risk Assessment -- Laboratory Support -- Zoonotic and Animal Diseases -- Viral Hepatitis -- E1. Zoonotic and animal diseases -- E2. Vaccine issues -- E3. H1N1 influenza -- E4. Novel surveillance systems -- E5. Antimicrobial resistance -- E6. Late-breakers I -- Antimicrobial resistance -- Influenza preparedness: lessons learned -- Zoonotic and animal diseases -- Improving preparedness for infectious diseases -- Laboratory support -- Early warning systems -- H1N1 influenza -- Policy implications and infectious diseases -- Modeling -- Molecular epidemiology -- Novel surveillance systems -- Tropical infections and parasitic diseases -- Strengthening public health systems -- Immigrant and refugee health -- Foodborne and waterborne infections -- Healthcare-associated infections -- Foodborne and waterborne infections -- New or rapid diagnostics -- Improving global health equity for infectious diseases -- Vulnerable populations -- Novel agents of public health importance -- Influenza preparedness: lessons learned -- Molecular epidemiology -- Zoonotic and animal diseases -- Vaccine-preventable diseases -- Outbreak investigation: lab and epi response -- H1N1 influenza -- laboratory support -- effective and sustainable surveillance platforms -- new vaccines -- vector-borne diseases and climate change -- travelers' health -- J1. Vectorborne diseases and climate change -- J2. Policy implications and infectious diseases -- J3. Influenza preparedness: lessons learned -- J4. Effective and sustainable surveillance platforms -- J5. Outbreak investigation: lab and epi response I -- J6. Late-breakers II -- Strengthening public health systems -- Bacterial/viral coinfections -- H1N1 influenza -- Novel agents of public health importance -- Foodborne and waterborne infections -- New challenges for old vaccines -- Vectorborne diseases and climate change -- Novel surveillance systems -- Geographic information systems (GIS) -- Improving global health equity for infectious diseases -- Vaccine preventable diseases -- Vulnerable populations -- Laboratory support -- Prevention challenges for respiratory diseases -- Zoonotic and animal diseases -- Outbreak investigation: lab and epi response -- Vectorborne diseases and climate change -- Outbreak investigation: lab and epi response -- Laboratory proficiency testing/quality assurance -- Effective and sustainable surveillance platforms -- Sexually transmitted diseases -- H1N1 influenza -- Surveillance of vaccine-preventable diseases -- Foodborne and waterborne infections -- Role of health communication -- Emerging opportunistic infections -- Host and microbial genetics -- Respiratory infections in special populations -- Zoonotic and animal diseases -- Laboratory support -- Antimicrobial resistance -- Vulnerable populations -- Global vaccine initiatives -- Tuberculosis -- Prevention challenges for respiratory diseases -- Infectious causes of chronic diseases -- O1. Outbreak investigation: lab and epi response II -- O2. Prevention challenges for respiratory diseases -- O3. Populations at high risk for infectious diseases -- O4. Foodborne and waterborne infections -- O5. Laboratory support: surveillance and monitoring infections -- O6. Late-breakers IIIAbstracts published in advance of the conference

Ultrasensitive detection of toxocara canis excretory-secretory antigens by a nanobody electrochemical magnetosensor assay.

peer reviewedHuman Toxocariasis (HT) is a zoonotic disease caused by the migration of the larval stage of the roundworm Toxocara canis in the human host. Despite of being the most cosmopolitan helminthiasis worldwide, its diagnosis is elusive. Currently, the detection of specific immunoglobulins IgG against the Toxocara Excretory-Secretory Antigens (TES), combined with clinical and epidemiological criteria is the only strategy to diagnose HT. Cross-reactivity with other parasites and the inability to distinguish between past and active infections are the main limitations of this approach. Here, we present a sensitive and specific novel strategy to detect and quantify TES, aiming to identify active cases of HT. High specificity is achieved by making use of nanobodies (Nbs), recombinant single variable domain antibodies obtained from camelids, that due to their small molecular size (15kDa) can recognize hidden epitopes not accessible to conventional antibodies. High sensitivity is attained by the design of an electrochemical magnetosensor with an amperometric readout with all components of the assay mixed in one single step. Through this strategy, 10-fold higher sensitivity than a conventional sandwich ELISA was achieved. The assay reached a limit of detection of 2 and15 pg/ml in PBST20 0.05% or serum, spiked with TES, respectively. These limits of detection are sufficient to detect clinically relevant toxocaral infections. Furthermore, our nanobodies showed no cross-reactivity with antigens from Ascaris lumbricoides or Ascaris suum. This is to our knowledge, the most sensitive method to detect and quantify TES so far, and has great potential to significantly improve diagnosis of HT. Moreover, the characteristics of our electrochemical assay are promising for the development of point of care diagnostic systems using nanobodies as a versatile and innovative alternative to antibodies. The next step will be the validation of the assay in clinical and epidemiological contexts