National Institute Of Virology Research Articles

Burden of influenza-associated respiratory and circulatory mortality in India, 2010-2013.

BackgroundInfluenza causes substantial morbidity and mortality worldwide, however, reliable burden estimates from developing countries are limited, including India. We aimed to quantify influenza-associated mortality for India utilizing 2010-2013 nationally representative data sources for influenza virus circulation and deaths.MethodsVirological data were obtained from the influenza surveillance network of 10 laboratories led by National Institute of Virology, Pune covering eight states from 2010-2013. Death data were obtained from the nationally representative Sample Registration System for the same time period. Generalized linear regression with negative binomial distribution was used to model weekly respiratory and circulatory deaths by age group and proportion of specimens positive for influenza by subtype; excess deaths above the seasonal baseline were taken as an estimate of influenza-associated mortality counts and rates. Annual excess death rates and the 2011 India Census data were used to estimate national influenza-associated deaths.ResultsEstimated annual influenza-associated respiratory mortality rates were highest for those ≥65 years (51.1, 95% confidence interval (CI) = 9.2-93.0 deaths/100 000 population) followed by those <5 years (9.8, 95% CI = 0-21.8/100 000). Influenza-associated circulatory death rates were also higher among those ≥65 years (71.8, 95% CI = 7.9-135.8/100 000) as compared to those aged <65 years (1.9, 95% CI = 0-4.6/100 000). Across all age groups, a mean of 127 092 (95% CI = 64 046-190,139) annual influenza-associated respiratory and circulatory deaths may occur in India.ConclusionsEstimated influenza-associated mortality in India was high among children <5 years and adults ≥65 years. These estimates may inform strategies for influenza prevention and control in India, such as possible vaccine introduction.

Laboratory preparedness for SARS-CoV-2 testing in India: Harnessing a network of Virus Research & Diagnostic Laboratories.

Background & objectives:An outbreak of respiratory illness of unknown aetiology was reported from Hubei province of Wuhan, People's Republic of China, in December 2019. The outbreak was attributed to a novel coronavirus (CoV), named as severe acute respiratory syndrome (SARS)-CoV-2 and the disease as COVID-19. Within one month, cases were reported from 25 countries. In view of the novel viral strain with reported high morbidity, establishing early countrywide diagnosis to detect imported cases became critical. Here we describe the role of a countrywide network of VRDLs in early diagnosis of COVID-19.Methods:The Indian Council of Medical Research (ICMR)-National Institute of Virology (NIV), Pune, established screening as well as confirmatory assays for SARS-CoV-2. A total of 13 VRDLs were provided with the E gene screening real-time reverse transcription-polymerase chain reaction (rRT-PCR) assay. VRDLs were selected on the basis of their presence near an international airport/seaport and their past performance. The case definition for testing included all individuals with travel history to Wuhan and symptomatic individuals with travel history to other parts of China. This was later expanded to include symptomatic individuals returning from Singapore, Japan, Hong Kong, Thailand and South Korea.Results:Within a week of standardization of the test at NIV, all VRDLs could initiate testing for SARS-CoV-2. Till February 29, 2020, a total of 2,913 samples were tested. This included both 654 individuals quarantined in the two camps and others fitting within the case definition. The quarantined individuals were tested twice - at days 0 and 14. All tested negative on both occasions. Only three individuals belonging to different districts in Kerala were found to be positive.Interpretation & conclusions:Sudden emergence of SARS-CoV-2 and its potential to cause a pandemic posed an unsurmountable challenge to the public health system of India. However, concerted efforts of various arms of the Government of India resulted in a well-coordinated action at each level. India has successfully demonstrated its ability to establish quick diagnosis of SARS-CoV-2 at NIV, Pune, and the testing VRDLs.

Covid-19 Testing Strategy of India - Current Status and the Way Forward.

Covid-19 Testing Strategy of India - Current Status and the Way Forward.

Declining trends in Hepatitis A seroprevalence over the past two decades, 1998–2017, in Pune, Western India

Reduction in seroprevalence of Hepatitis A virus (HAV) is known to be associated with improvements in socioeconomic conditions of the community. National Institute of Virology, Pune has been studying seroprevalence of hepatitis viruses in Pune region over the past four decades. In total, 1438 samples were collected from urban general (UGEN), urban lower socioeconomic stratum (ULSES) and rural (RURAL) populations of the Pune district. Based on estimates in previous studies, subjects were enrolled from age groups '6-10', '15-25' and '40 + ' years. HAV seroprevalence in younger population showed a significant decline. A significant decline in HAV seroprevalence in '15-25' years age group in UGEN (from 85.9% to 73.9%; OR = 0.46, 95% CI: 0.25-0.86) and RURAL (from 98.6% to 91.4%; OR = 0.15, 95% CI: 0.05-0.45) populations suggested that the trend probably started more than a decade ago. Seroprevalence of HAV among ULSES '6-10' children was found to be significantly higher (70.4%) than that among the RURAL children (44.2%; OR = 3.0, 95%CI: 1.7-5.2) and UGEN children (40.4%; OR = 3.5, 95%CI: 1.8-6.7). In view of increasing rates of urbanisation in India, ULSES population needs special consideration while designing future studies and viral hepatitis vaccination/elimination strategies. Our findings call for robust population-based studies that consider heterogeneity within populations and dynamics of socio-economic parameters in various regions of a country.

Clinical, microbiological profile of dengue cases reported at a tertiary care hospital in Telangana, India

Introduction: Dengue is the most common disease among all the arthropod borne viral diseases. Dengue viruses (DV) belong to the family Flaviviridae, and there are four serotypes of the virus referred to as DV-1, DV-2, DV-3, and DV-4 Dengue is the most common and widespread arboviral infection in the world today. It is an increasingly prevalent tropical arbovirus infection with significant morbidity and mortality. Materials and Methods: The study was carried out in the department of microbiology at Ronald Ross Institute of Tropical Diseases for a period of 6 years i.e. from January 2011 to December 2017. Blood was collected from each patient suspected to be suffering from dengue, at least 5 days after onset of fever. Serum was tested for the presence of dengue NS1 antigen and antihuman IgM antibodies using Panbio Dengue Early enzyme-linked immunosorbent assay (ELISA) kit and National Institute of Virology. Results: A total of 5181 samples were tested over a period of 7 years i.e. from 2011-2017. Out of which 1440 (27.79%) were sero-positive for dengue with symptoms of classical dengue fever. IgM in 1033(19.9%) NS1- 320(6.2%). A male preponderance was observed (905, 62.8%). Conclusion: As, during epidemic and nonepidemic years, dengue infections are mostly seen in post-monsoon season, hence preventive measures should be in full swing at the very onset of the monsoons

1790. Single-Center Experience and Lessons Learnt from Management of Nipah Virus Outbreak in India

BackgroundNipah virus (NiV) is re-emerging zoonotic RNA virus belonging to Paramyxoviridae family. Suspecting Nipah virus in a NiV naive tropical area is a challenge. NiV management is further confounded by acute presentation, high mortality, broad species tropism, multiple modes of transmission, difficulty to diagnose and lack of definitive treatment.MethodsRecent NiV outbreak that lasted for approximately 1 month (2–29 May 2018) and resulted in 23 cases with a case-fatality rate of 91%. We present clinical summary and management of five cases managed at Baby Memorial Hospital, Kozhikode, India from May 17, 2018 to May 30, 2018 and were epidemiologically linked to the index case. All patients presented with initial nonspecific prodromal symptoms of fever, muscle pain, watery diarrhea. Median age was 53 years, four were males, median hospital stay was 3 days, median incubation period of was days. Further complications, included encephalitis with viral bronchopneumonia/acute respiratory distress syndrome (ARDS) in 100 %, patients, encephalitis with viral bronchopneumonia/ARDS with myocarditis in 60 %patients, despite attempted therapy with ribavirin all patients developed cardiorespiratory arrest and succumbed to the illness. ResultsHematological Investigations showed normal TLC with a mean of 7,920 cells/ mm3, mild thrombocytopenia (mean 1,57,800) high Hb 16.12(SD1.10), ESR 19 mm/hr, DLC-N 82% high relative neutrophilic cytosis. Normal liver and renal function, Na+ 133 meq/L. CSF analysis showed high opening pressure, 100% lymphocytic pleocytosis, mean CSF sugar 118 mg/100mL, CSF protein 73.6. CT chest -bilateral airspace opacities and ground glassing. Brain FLAIR sequence showed nonspecific hyperintensities in white matter and brainstem correlating with vasculitic changes. Laboratory diagnosis of NiV was made by Real-Time RT–PCR on throat swab, blood, urine and cerebrospinal fluid by Manipal virus research center and National Institute of Virology. Pathological autopsy was done in 2 cases and found noncontributory.ConclusionWe report clinical and public health management experience from one of the three hospitals managing the patients affected with NiV. Managing outbreaks of high infectivity requires persistent organized and committed healthcare interventions Disclosures All authors: No reported disclosures.

Seroprevalence of influenza A H1N1 (swine) infection in the human population in a cantonment

BackgroundVarious serosurveys and studies were conducted globally on pandemic influenza. H1N1 virus reported so far provides ample evidence of differing perspectives, regarding its epidemiology especially with regard to prevalence, populations groups, and behaviour related to vaccine acceptance. A multigroup, cross-sectional survey among 658 healthy subjects was carried out, in Pune among students, health-care workers (HCWs), and soldiers to assess the seroprevalence of pandemic influenza H1N1 virus and its associated factors. MethodsThe total sample size, based on forecasted prevalence of 33%, worked out to be 640. We studied 658 subjects including 103 students, 201 HCWs, and 354 serving soldiers. The sample for each group was selected from the respective study population by simple random sampling using a random number table. Haemagglutination inhibition test was carried out at the National Institute of Virology. ResultsThe overall seroprevalence of pandemic influenza H1N1 (2009) virus was found to be 46.5% (95% confidence interval 42.6–50.4) which was adjusted to 39.4% after excluding those vaccinated. The availability of vaccine for high-risk group such as HCWs did not find much favour with the HCWs who did not accept vaccine for various reasons. Whereas only one student was vaccinated, 21.4% of HCWs and 32.5% of soldiers were vaccinated. ConclusionBased on high seroprevalence of antibodies against H1N1 virus during pandemic, vaccination of general population is not recommended. However, high-risk groups and HCWs need to be protected with flu vaccine. There is a need to encourage HCWs for accepting vaccination.

Laboratory-based investigation of fever with rash cases in the Maharashtra State - India, 2014 to 2017.

The Maharashtra State (MS), India, launched measles surveillance in the year 2013. From 2014 to 2017, specimens from the patients presenting with fever and skin rashes were received at the National Institute of Virology, Pune. From 36 districts of the MS, 2795 cases (1428 males and 1367 females) were referred for the laboratory diagnosis of measles and rubella using immunoglobulin M enzyme immunoassay and/or RT-PCRs. The majority of the cases (93.3%, n = 2609) were under 15 years of age. About 17.7% (494) cases had a history of measles immunization (one dose) during their childhood. Virus isolation was attempted from 107 throat swabs and 84 urine samples obtained from 191 cases using Vero hSLAM cells. The results confirmed measles in 1756 and rubellain 282 fever with rash cases by serological and molecular tools. Precisely, 170 of 382 and 35 of 149 specimens were positive for measles and rubella RT-PCRs, respectively. Sequencing of the representative PCR products showed the circulation of measles virus genotypes D4 (n = 26) and D8 (n = 107), and rubella virus genotype 2B (n = 1). Twenty-three measles viruses were isolated and genotyped, of which, 6 were D4 and 17 were D8 genotypes. Amongst the measles-immunized individuals, 51.2% (253/494) had laboratory-confirmed measles. Overall, 72.9% fever with skin rash cases (n = 2038) from the MS was laboratory confirmed for either measles or rubella. The contribution of measles was higher than rubella in the fever with rash cases. As expected, more fever with rash cases were documented in children compared with adults and highlighted the need to increase measles-rubella immunization coverage.

Towards global health security: response to the May 2018 Nipah virus outbreak linked to Pteropus bats in Kerala, India

### Summary box This report summarises the complete outbreak timeline and findings, including the association of infection and Pteropus bats, and makes the link to global health security in India....

Chickenpox and measles clusters among college students in Pune, Maharashtra.

Chickenpox and measles, both vaccine preventable febrile rash illnesses, present in a comparatively severe form among young adults/adults than among children. Immunity levels against chickenpox are not known in India and those against measles have been found variable across the country. Places where students or adults/young adults from various parts of the country come together pose a peculiar challenge in preventive policy making regarding these diseases. In this article, we present findings from parallel outbreaks of the two diseases in a graduate/postgraduate institute in the city of Pune. A team from National Institute of Virology [Pune] investigated outbreak of febrile rash illness in a premier graduate institute and found that it was a case of two parallel outbreaks of chickenpox and measles. In this outbreak chickenpox cases did not present with greater severity but measles cases were severe. The concerned institute hosts more than 800 students and 300 staff including faculty. These outbreaks were contained because of the alert physician in the institute; but it also highlights a need for uniform policies across such educational institutions in the country.

Measles virus genotypes circulating in India, 2011-2015.

The Government of India is accepted to participate in the measles elimination and rubella control goal 2020, hence genetic characterization of measles viruses (MeV) becomes essential. At National Reference Laboratory (National Institute of Virology, Pune), the throat swabs/urine specimens (n = 380) or PCR products (n = 219) obtained from the suspected measles cases were referred for the molecular testing and subsequently, MeV nucleoprotein (N) gene sequencing/genotyping. In addition, 2,449 suspected measles cases, mainly from the Maharashtra state were referred for the laboratory diagnosis. A detailed study was performed on N gene sequences obtained during last two decades. Indian MeV sequences obtained during 2011-2015 were compared with 1996-2010 sequences and genetic divergence was studied. Circulation of measles genotypes B3 (n = 3), D4 (n = 49), and D8 (n = 351) strains were observed in 19 States and three Union Territories of India. In addition, 64 measles viruses were isolated from 253 throat swab or urine specimens obtained from the suspected measles cases. During 2011-2015, 67.9% (1,663/2,449) suspected measles cases were laboratory confirmed. Molecular studies showed circulation of measles genotype B3 in India along with prominently circulating genotypes D4 and D8 except D7 strains. The genetic diversion within Indian B3, D4, and D8 genotypes was 0.3%, 1.1%, and 2.1%, respectively. The genetic divergence of Indian B3, D4, and D8 measles strains with the WHO reference sequences was 2.5%, 2.6%, and 1.8%, respectively. It is crucial data for national immunization program. More measles/rubella genotyping studies are necessary to track transmission and to support measles elimination and rubella control. J. Med. Virol. 89:753-758, 2017. © 2016 Wiley Periodicals, Inc.

Crimean-Congo Hemorrhagic Fever Virus IgG in Goats, Bhutan

To The Editor: Crimean-Congo hemorrhagic fever (CCHF) is a highly infectious tickborne disease caused by a high-risk group of viruses belonging to the family Bunyaviridae (1,2). In humans, the overall case-fatality rate of CCHF is ≈30%, but in severe and hospitalized patients, fatalities may be up to 80% (3,4). CCHF is widespread in various countries in Africa, Asia, and Europe; the virus had been identified in humans in China, Pakistan, and Afghanistan and has been recently reported for the first time in humans in India (4–7). Humans can be infected by bites from infected ticks, mainly of the Hyalomma genus; by unprotected contact with blood or tissue of viremic patients; or during slaughtering of infected animals. In addition, nosocomial infections are found in humans (1,4,8,9). Fatal cases of CCHF in humans were confirmed in Ahmadabad in India in 2011, but a recent serosurvey in livestock showed that this disease has widespread seroprevalence in domestic animals across India (7–10). Bhutan shares a long, porous border with India, and animals and humans frequently cross the border. Comprehensive surveillance was needed to determine the presence of CCHF virus (CCHFV) in livestock in Bhutan and to assess risk for zoonotic infection in humans. During October 2015, in collaboration with the National Centre for Animal Health Bhutan, we retrospectively tested serum samples collected during April–May 2015 from 81 goats and 92 cattle for CCHFV-specific IgG by using ELISA kits (Sheep/goat anti-CCHFV IgG ELISA kit and Cattle anti-CCHFV IgG ELISA kit; National Institute of Virology, Pune, India), as described (10). CCHFV IgG was detected in 31 (38.2%) goats; no cattle had positive results. The samples from goats, which were collected in early 2015 as part of surveillance of peste des petits ruminants, originated from the southern district of Sarpang, which shares a porous border with the state of Assam in India (Figure). The samples from cattle were collected from the National Nublang Breeding Center (Trashigang district) and the National Jersey Breeding Center (Samtse district) (Figure). Findings indicated that all goats that tested positive for CCHFV were reported to have been either bred within households that kept goat herds or procured from other villages within the district. Exact sources of those seropositive goats could not be ascertained. However, in a few instances in the past, breeding goats (male and female) were procured from India by the Bhutan government and distributed to farmers for breed improvement. We also believe that cross-border movement of animals and unofficial imports of goats by farmers along the porous borders of southern Bhutan likely occurred. Furthermore, a large number of dairy cattle are imported annually from India for enhancing milk production and breeding purposes. Not all imported animals (both cattle and goats) were tested for CCHF because of a lack of diagnostic facilities and the negligible occurrence of the disease in livestock. Figure Locations in Bhutan where serum samples were collected from goats (triangles) and cattle (square and circle) and tested for Crimean-Congo hemorrhagic fever virus. The shaded area shows the boundaries of Sarpang district and subdistricts, where samples ... Our findings indicate that the risk of importing emerging infectious diseases along with live animals poses a serious risk to public health. Consequently, detailed risk-based surveillance is necessary to understand the complete scenario of CCHFV prevalence in livestock in Bhutan because Hyalomma tick species, the primary vectors of CCHF, are present on animals here. In addition, a survey among at-risk human populations is also needed. Findings from these surveillance activities would help institute more diagnostic facilities and risk-based surveillance and assist in developing a preparedness plan at the human–animal interface. Although our study has limitations because of the low number of serum samples tested from limited animal species from only 3 areas, the study provides evidence that CCHFV is circulating in goats in Bhutan.

Laboratory confirmation of rubella infection in suspected measles cases.

As a part of measles outbreak based surveillance undertaken by the World Health Organization India, suspected measles cases were referred for the laboratory diagnosis at National Institute of Virology (NIV) Pune and NIV Unit Bengaluru. Altogether, 4,592 serum samples were referred during 2010-2015 from the States of Karnataka (n = 1,173), Kerala (n = 559), and Maharashtra (n = 2,860). Initially, serum samples were tested in measles IgM antibody EIA and samples with measles negative and equivocal results (n = 1,954) were subjected to rubella IgM antibody detection. Overall, 62.9% (2,889/4,592) samples were laboratory confirmed measles, 27.7% (542/1,954) were laboratory confirmed rubella and remaining 25.2% (1,161/4,592) were negative for measles and rubella. The measles vaccination status was available for 1,206 cases. Among the vaccinated individuals, 50.7% (612/1,206) were laboratory confirmed measles. The contribution of laboratory confirmed measles was 493 (40.8%) from Maharashtra, 90 (7.5%) from Karnataka, and 29 (2.4%) from Kerala. Since, 1/3rd of suspected measles cases were laboratory confirmed rubella, an urgent attention needed to build rubella surveillance in India. Additional efforts are required to rule out other exanthematous disease including Dengue and Chikungunya in measles and rubella negatives. J. Med. Virol. 88:1685-1689, 2016. © 2016 Wiley Periodicals, Inc.

Diagnostic potential of monoclonal antibodies against the capsid protein of chikungunya virus for detection of recent infection.

Chikungunya fever is self-limiting. However, neurological and hemorrhagic complications have been seen in recent outbreaks. The clinical manifestations of this disease are similar to those of dengue virus infection, indicating the need for differential diagnosis in areas such as India, which are endemic for both viruses. The aim of the present study was to develop monoclonal antibodies (MAbs) against Chikungunya virus (CHIKV) and assess their use in MAb-based IgM capture ELISA (MAC ELISA). The ELISA detects CHIKV-specific IgM antibodies, a marker of recent infection, in a patient's serum. One IgG1 and two IgM isotype hybrids were obtained. All of the subclones derived from the IgG1 hybrid recognized the C protein of CHIKV. The anti-C MAb ClVE4/D9 was the most promising as a detector antibody in MAC ELISA (C-MAb ELISA) yielding higher positive-to-negative (P/N) ratios. When compared with the CHIKV MAC ELISA kit developed by the National Institute of Virology (NIV), Pune (NIV MAC ELISA), the sensitivity of the test was 87.01% with 100% specificity. The positive and negative predictive values (PPV and NPV) were 100% and 94.47%, respectively. In precision testing, standard deviation (SD) and coefficient of variation (% CV) values of the C-MAb ELISA were within acceptable limits. The C-MAb ELISA detected anti-CHIKV IgM in serum of patients up to five months after the onset of infection, indicating that anti-C MAbs have strong potential for use in MAC ELISA to detect recent CHIKV infection.

Vesiculobullous viral exanthem due to chikungunya in an infant.

Sir, Chikungunya is an self-limiting arboviral disease caused by the chikungunya virus. It is transmitted mainly by the mosquito vectors Aedis aegypti and Aedis albopictus that breed in urban and semi-urban settings on clean standing (but stagnant) water.[1] Various dermatologic manifestations of chikungunya reported in infants include generalized erythema, maculopapular rash, vesiculobullous lesions, and skin peeling.[2] A 6-month-old child presented with high grade fever of three days and vesiculobullous rash of one day duration. Rash was initially erythematous and later turned dusky by the third day with associated blistering. Discrete, black flaccid vesicles and bullae were then noted on the trunk and perineum and spread to the extremities, sparing the face and mucosae [Figures ​[Figures11 and ​and2].2]. The child was otherwise unremarkable with no history of associated seizures, joint swelling, vomiting, or loose stools. There was no history of any medication intake prior to onset of blistering. Hemogram, liver function tests, renal function tests, and cerebrospinal fluid analysis were within normal limits. Blood culture and blister fluid culture were sterile. Serology for chikungunya by IgM antibody capture enzyme-linked immunosorbent assay (MAC-ELISA) (National Institute of Virology, Pune, India) was found to be positive from the serum sample sent on the sixth day of fever. An early vesicle was biopsied which on histopathological examination revealed intraepidermal bulla, dilated dermal blood vessels filled with fibrin and epidermal necrosis [Figure 3]. Child was treated symptomatically with paracetamol and fever subsided by the seventh day. Vesiculobullous rash started exfoliating by the sixth day and subsided completely without any pigmentary change by the tenth day. Figure 1 Purpuric vesicles and bullae over the trunk and extremities Figure 2 Purpuric vesicles and bullae over the gluteal region Figure 3 Histopathology of vesicle demonstrating intraepidermal cleft and dilated dermal blood vessels filled with fibrin and epidermal necrosis (H and E, ×100) In chikungunya, generalized erythematous rash develops abruptly during the first two days of fever followed by maculopapular rash in a centrifugal distribution on the second day of fever usually disappearing by the sixth day. Palms and soles are involved in around two-thirds of infants, but facial involvement is rare. Vesiculobullous eruptions in infants with chikungunya have been reported.[2,3,4] They usually present as sudden onset of flaccid vesicles and bullae usually on the fourth day of fever over the lower limbs that then spread to the perineum, abdomen, chest, and upper limb sparing the face and scalp. Lesions exfoliate by the sixth day and heal by the tenth day sometimes leaving behind pigmentary changes.[2] Clinical diagnosis can be confirmed by virus isolation, viral RNA by real-time polymerase chain reaction, virus specific immunoglobulin M antibodies by MAC-ELISA in a single serum sample collected in an acute state or four-fold increase in immunoglobulin G values in samples collected at least three weeks apart.[5] There is no specific antiviral therapy. Supportive treatment with paracetamol or other nonsalicylate analgesics is the mainstay of management. All suspected cases should be kept in mosquito nets during the febrile period and mosquito control measures should be adopted.[4] We report this case to highlight the interesting presentation of chikungunya in an infant in the form of vesiculobullous lesions. Chikungunya should be included in the differential diagnosis of febrile vesiculobullous eruption in infants.

Current status of dengue and chikungunya in India.

Dengue, a Flavivirus and chikungunya, an Alphavirus, transmitted by Aedes mosquitoes, are a cause of great concern to public health in India. Every year, thousands of individuals are affected and contribute to the burden of health care. Dengue outbreaks have continued since the 1950s but severity of disease has increased in the last two decades. Chikungunya outbreaks started in the 1960s and dwindled to sporadic cases until a resurgence in 2006. Based on the data of National Vector Borne Disease Control Programme (NVBDCP), the number of cases reported in 2013 was about 74 454 for dengue with 167 deaths and 18 639 for chikungunya. The number of cases reported is increasing, probably because of the availability of IgM detection kits produced and distributed by National Institute of Virology through NVBDCP and better reporting. In the absence of well-structured epidemiological studies, this review attempts to summarize reports on dengue and chikungunya outbreaks from various regions of India. For dengue, young adults are the major group affected; the severity of disease in India is still lower than that reported elsewhere in South-East Asia; and paediatric cases of dengue haemorrhagic fever have a high mortality. For chikungunya, all age groups are affected but severe manifestations are more often seen in children. Persisting arthralgia, neurological syndromes and non-neurological manifestations are recorded. Changes in the genotype and mutations in the genome have been detected for both dengue and chikungunya viruses. The review ends with a short summary of the most recent vector-control studies.

Post mortem findings in fatal H1N1 infection

Background: A novel H1N1 influenza virus emerged in April 2009, and rapidly reached pandemic proportion. In India since May 2009 to August 2010, India has reported nearly 37,000 H1N1 cases and 1833 deaths. Aims & Objective: The present study was undertaken to find the cause of death and various histopathological changes which is responsible for high mortality. Materials and Methods: This is a retrospective study of five patients who died due to H1N1. Tissues for histopathological examination were received in Pathology department. All the five patients were confirmed for Novel Influenza A (H1N1) by National Institute of Virology. Results: Four Patients were female in ANC period and a single patient was a young adult. Histopathological examination revealed diffuse alveolar damage (DAD) in both the lungs along with necrotising bronchopneumonia, presence of thrombi in peripheral pulmonary vasculature along with involvement of large vessel was seen in all the cases. Haemophagocytosis was also seen in all the cases. Conclusion: Thus the main cause of death was due to diffuse alveolar damage (DAD). Thus DAD associated with other complication in lungs and Haemophagocytosis in spleen should raise the suspicion of Influenza A (H1N1) virus.

Crimean-Congo Hemorrhagic Fever: Current Scenario in India.

India is considered as a hot spot for emerging infectious diseases. In the recent past many infectious diseases of emerging and re-emerging nature have entered this subcontinent and affected a large number of populations. A few examples are Nipah, Avian influenza, Pandemic influenza, severe acute respiratory syndrome corona virus and Chikungunya virus. These diseases have not only affected human and animal health but also economy of the country on a very large scale. During December 2010, National Institute of Virology, Pune detected Crimean-Congo hemorrhagic fever virus specific IgG antibodies in livestock serum samples from Gujarat and Rajasthan states. Subsequently, during January 2011 Crimean-Congo hemorrhagic fever virus was confirmed in a nosocomial outbreak, in Ahmadabad, Gujarat, India. Retrospective investigation of suspected human samples confirmed that the virus was present in Gujarat state, earlier to this outbreak. This disease has a case fatality rate ranging from 5 to 80 %. Earlier presence of hemagglutination inhibition antibodies have been detected in animal sera from Jammu and Kashmir, the western border districts, southern regions and Maharashtra state of India. The evidences of virus activity and antibodies were observed during and after the outbreak in human beings, ticks and domestic animals (buffalo, cattle, goat and sheep) from Gujarat State of India. During the year 2012, this virus was again reported in human beings and animals. Phylogenetic analysis showed that all the four isolates of 2011, as well as the S segment from specimen of 2010 and 2012 were highly conserved and clustered together in the Asian/Middle East genotype IV. The S segment of South-Asia 2 type was closest to a Tajikistan strain TADJ/HU8966 of 1990. The present scenario in India suggests the need to look seriously into various important aspects of this zoonotic disease, which includes diagnosis, intervention, patient management, control of laboratory acquired and nosocomial infection, tick control, livestock survey and this, should be done in priority before it further spreads to other states. Being a high risk group pathogen, diagnosis is a major concern in India where only a few Biosafety level 3 laboratories exist and it needs to be addressed immediately before this disease becomes endemic in India.

Epidemiological characteristics of H1N1 positive deaths: A study from tertiary care hospital in western India

Background: In India as of 31st March 2010, there were 30917 laboratory confirmed H1N1 positive cases out of which 1453 were deaths with positivity index of 22.87% and mortality was 4.8%. But there was alarming sign after comparing these figures with those on 3rd October 2010 which showed 44687 confirmed H1N1 Positive cases with 2574 deaths with rise in positivity index to 23.3% and mortality rate of 5.7%. From the available data core issue of deaths occurring due to H1N1 positivity in short period of time in this year and risk factors associated with fatality were needed to look in detail. Aims & Objective: To study the epidemiologic characteristics of reported deaths, high-risk profiles linked with underlying disease among reported deaths who died after infection with H1N1 influenza. Material and Methods: Retrospective Record based study. Data was collected from prescribed format for swine flu patients admitted in IIW (Identified Isolation Ward) of Tertiary care hospital in Pune, State Maharashtra, India. Epidemiological characteristics like age, gender, residential address, time lag of Oseltamivir (Tamiflu) initiation, co morbidities, etc. were included. Confirmation of H1N1 positivity among cases was done by conducting Real Time PCR at National Institute of Virology, Pune. Trend of Occurrence of positive cases and death was drawn. Results were presented in the form of percentages for the respective variables. Case fatality rate was calculated for H1N1 Deaths. Results: Maximum positive cases and deaths were in the month of August 2010. Deaths were more among age group of 20 years and above and female’s proportion was high. Thirty one deaths were in Pune urban area from April 2010 to September 2010. Time lag in initiation of Oseltamivir (Tamiflu) was seen among 63 (79%) deaths. Asthma, Diabetes and hypertension were co morbid condition and pregnancy was associated condition with H1N1 fatality. Conclusion: Mortality was seen among adult population. Time lag in initiation of Oseltamivir (Tamiflu) was seen among majority of deaths.

Incidence of Japanese Encephalitis among Acute Encephalitis Syndrome Cases in West Bengal, India

Background and Objectives. Japanese encephalitis (JE) is the most important cause of acute and epidemic viral encephalitis. Every year sporadic JE cases are reported from the various districts of West Bengal, indicating its endemicity in this state. JE vaccination programme has been undertaken by the State Health Department of West Bengal. This study was aimed at seeing the present scenario of JE among acute encephalitis syndrome (AES) cases in West Bengal. Materials and Methods. Blood and/or CSF samples were referred from suspected AES cases to the referral virology laboratory of the Calcutta School of Tropical Medicine from different hospitals of Kolkata. IgM antibody capture ELISA was performed on the CSF and serum samples by JE virus MAC ELISA kit supplied by the National Institute of Virology, Pune. Results. The present study reveals that 22.76% and 5% of the AES cases were positive for JE IgM in 2011 and 2012, respectively. JE is mainly prevalent in children and adolescents below 20 years of age with no gender predilection. Although the percentages of JE positive cases were high in 2011, it sharply decreased thereafter possibly due to better awareness programs, due to mass vaccination, or simply due to natural epidemiological niche periodicity due to herd immunity.