Expert consensus and recommendations on the live attenuated hepatitis A vaccine and immunization practices in India.

While Hepatitis A Virus (HAV) vaccination in global immunization programs has shown a virtual elimination of the disease within few years of the vaccination program, changing epidemiological landscape in India underscores the need for evidence-based, updated guidance on immunization practices. In May 2024, a panel of 15 distinguished opinion leaders and an organizing committee convened for an intensive, face-to-face advisory board meeting on high burden of HAV infection among adults, increased mortality rate in adolescents, symptomatic presentation in children, and evolving landscape globally and within India. Extensive comparable deliberations on long-term follow-up data from India and data from country of origin advocated immunogenicity, tolerability, and long-term protective effects of single-dose live attenuated HAV vaccine in children.

Dengue infection changes the expressions of CD154 and CD148 in human platelets.

Platelets are essential for hemostasis and vascular integrity. Platelets recognize dengue virus through the DC-SIGN receptor. Upon pathogen recognition, platelets rapidly modulate the expression of adhesion molecules to trigger immune cell interactions and regulate the immune response.

Mucosal delivery of a prefusogenic-F, glycoprotein, and matrix proteins-based virus-like particle respiratory syncytial virus vaccine induces protective immunity as evidenced by challenge studies in mice.

RSV infection remains a serious threat to the children all over the world, especially, in the low-middle income countries. Vaccine delivery via the mucosa holds great potential for inducing local immune responses in the respiratory tract. Previously, we reported the development of highly immunogenic RSV virus-like-particles (RSV-VLPs) based on the conformationally stable prefusogenic-F protein (preFg), glycoprotein and matrix protein.

Evaluation and Immunogenicity of Combined Liposome-Based Vaccine Candidates against Hepatitis E and B Viruses in Rhesus Monkeys.

The administration of vaccines using a combination approach ensures better coverage and reduces the number of injections and cost. The present study assessed liposome-complexed DNA-corresponding proteins of hepatitis E and B viruses (HEV and HBV) as combined vaccine candidates in rhesus monkeys. The HEV and HBV components consisted of 450 bps, neutralizing the epitope/s (NE) region, and 685 bps small (S) envelope gene-corresponding proteins, respectively.

A Phase 1, double-blind, randomized, placebo-controlled study to evaluate the safety and immunogenicity of a tetravalent live attenuated dengue vaccine in adults.

Background: Dengue fever is an important public health problem, especially in Asia and South America. A tetravalent live attenuated dengue vaccine was manufactured in India after receipt of vaccine strains from NIAID, NIH, USA.

Methods: This was a Phase 1, double-blind, randomized, placebo-controlled study performed in 60 healthy adults of 18 to 45 years.

Variable neutralizing antibody responses to 10 SARS-CoV-2 variants in natural infection with wild- type (B.1) virus, Kappa (B.1.617.1), and Delta (B.1.617.2) variants and COVISHIELD vaccine immunization in India: utility of the MSD platform.

For the efficacy of COVID-19 vaccines, emergence of variants accumulating immune-escape mutations remains a major concern. We analyzed the anti-variant (n = 10) neutralization activity of sera from COVID-19 patients infected with Wuhan (B.1), Kappa, and Delta variants and COVISHIELD vaccine recipients with (prepositives) or without (prenegatives) prior antibody positivity using V- PLEX ACE2 Neutralization Kit from MSD.

SARS-CoV-2 breakthrough infections during the second wave of COVID-19 at Pune, India.

Breakthrough infections following SARS-CoV-2 vaccination remain the global concern. The current study was conducted during the second wave of COVID-19 (1st March-7th July 2021) in Pune, India, at two tertiary care hospitals. Of the 6,159 patients diagnosed as COVID-19, 372/2,210 (16.

Immunogenicity of two COVID-19 vaccines used in India: An observational cohort study in health care workers from a tertiary care hospital.

COVID-19 pandemic witnessed rapid development and use of several vaccines. In India, a country-wide immunization was initiated in January 2021. COVISHIELD, the chimpanzee adenoviral-vectored vaccine with full-length SARS-COV-2 spike insert and COVAXIN, the whole virus-inactivated vaccines were used.

Immunoglobulin G Subclass Response After Chikungunya Virus Infection.

Various vaccines are under development to prevent chikungunya (CHIKV) infection. For the assessment of the CHIKV vaccine-induced antibody response, it is extremely important to understand antibody response after the infection has occurred. Previously, we assessed IgG response in samples from healthy donors using I-CHIKV and found that IgG1 was the predominant subclass induced after CHIKV infection followed by IgG4.

Time dependent decline of neutralizing antibody titers in COVID-19 patients from Pune, India and evidence of reinfection.

Purpose: To assess modulation of neutralizing antibody titers in COVID-19 patients and understand association of variables such as age, presence of comorbidity, BMI and gender with antibody titers.

Methods: Patients (n = 100) diagnosed from 20th March 2020 to 17th August 2020 and treated at two large hospitals from Pune, India were included and followed up (clinical and serologic) for varied periods. IgG-anti-SARS-CoV-2 (Spike protein-based ELISA) and neutralizing antibody titers (NAb, PRNT) were determined in all the samples.

Emergence of two distinct variants of SARS-CoV-2 and an explosive second wave of COVID-19: the experience of a tertiary care hospital in Pune, India.

The emergence of novel variants of SARS-CoV-2 in several countries has been associated with increased transmissibility or reduced neutralization potential of antibodies against the Wuhan virus (wild type). From August 2021 onwards, India experienced a progressive decline in the number of active SARS-CoV-2 infections, indicative of a downward trend in the explosive second wave. This prospective study was conducted quarterly for one year (May 2020 to June 2021) at a tertiary care hospital in the city of Pune in western India.

Elevated Levels of Neutrophil Activated Proteins, Alpha-Defensins (DEFA1), Calprotectin (S100A8/A9) and Myeloperoxidase (MPO) Are Associated With Disease Severity in COVID-19 Patients.

Understanding of the basis for severity and fatal outcome of SARS-CoV-2 infection is of paramount importance for developing therapeutic options and identification of prognostic markers. So far, accumulation of neutrophils and increased levels of pro-inflammatory cytokines are associated with disease severity in COVID-19 patients. In this study, we aimed to compare circulatory levels of neutrophil secretory proteins, alpha-defensins (DEFA1), calprotectin (S100A8/A9), and myeloperoxidase (MPO) in COVID-19 patients with different clinical presentations.

Perinatal transmission of SARS-CoV-2 and transfer of maternal IgG/neutralizing anti-SARS-CoV-2 antibodies from mothers with asymptomatic infection during pregnancy.

Purpose: COVID-19 pandemic remains a serious public health threat worldwide. In view of the limited data on the risk of perinatal transmission of SARS-CoV-2 and transfer of maternal anti-SARS-CoV-2 antibodies, the present study was undertaken.

Methods: A prospective study including 57 pregnant women with a positive SARS-CoV-2 RNA test (SARS-CoV-2-RNA+) and 59 neonates born to them was conducted at Pune, India.

Performance assessment of SARS-CoV-2 IgM & IgG ELISAs in comparison with plaque reduction neutralization test.

Background & Objectives: Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) continues to be a devastating pandemic. This study was aimed at performance assessment of SARS-CoV-2 IgM and IgG ELISAs, and investigation of their utility for patient diagnosis and sero-epidemiologic investigations.

Methods: Serum/plasma samples from COVID-19 patients or asymptomatic contacts (n=180) and healthy donors (n=90) were tested in parallel using two commercial IgM ELISAs (Erbalisa and Inbios), and four IgG ELISAs (Kavach, Euroimmun, Erbalisa and Inbios) along with an indigenous β-propiolactone inactivated virus-based ELISA (IRSHA-IgG-ELISA).

Early and High SARS-CoV-2 Neutralizing Antibodies Are Associated with Severity in COVID-19 Patients from India.

Patients with SARS-CoV-2 infection have a wide spectrum of clinical presentations, from asymptomatic infection, to mild illness, to severe disease with recovery or fatal outcome. Immune correlates of protection are not yet clear. To understand the association between presence and titers of neutralizing antibodies (NAb) with recovery, we screened 82 COVID-19 patients classified in mild (n = 56) and severe (n = 26) disease groups on different days post onset of disease and 27 viral RNA-positive asymptomatic contacts examined within 1 week of the identification of index cases.

Complete genome characterization and evolutionary analysis of dengue viruses isolated during 2016-2017 in Pune, India.

Dengue is the most common mosquito-borne viral infection in tropical and sub-tropical countries. In the recent years, frequent dengue outbreaks are being reported in many parts of India. DENV circulates as four independent serotypes posing a major public health threat around the globe.

Immune Response of Indian Preterm Infants to Pentavalent Vaccine Varies With Component Antigens and Gestational Age.

Childhood vaccination plays critical role in protecting infants from several dreaded diseases. Of the global 15 million preterm (PT) infants with compromised immune system born annually, India contributes to >3.5 million.

Isolation and genetic characterization of SARS-CoV-2 from Indian patients in a single family without H/O travel abroad.

In view of the rapidly progressing COVID-19 pandemic, our aim was to isolate and characterize SARS-CoV-2 from Indian patients. SARS-CoV-2 was isolated from nasopharyngeal swabs collected from the two members of a family without any history of (H/O) travel abroad. Both the virus isolates (8003 and 8004) showed CPE on day 3 post-inoculation, viral antigens by immunofluorescence assay and produced distinct, clear and uniform plaques.

Antibody (IgA, IgG, and IgG Subtype) Responses to SARS-CoV-2 in Severe and Nonsevere COVID-19 Patients.

For the assessment of vaccine-induced immune response and to understand the role of antibodies in neutralization, it is necessary to assess dynamics of various antibodies in patients with different clinical manifestations. This study aims to quantitate circulating levels of IgA/IgG and IgG subtypes induced at different days postonset of symptoms, in severe and nonsevere patients. For this, serum or plasma samples ( = 146) collected from 79 COVID-19 patients were used.

Age-Dependent Evaluation of Immunoglobulin G Response after Chikungunya Virus Infection.

Current chikungunya antibody prevalence and titers are likely to differ based on the exposure rates before the 2006 reemergence in India. For vaccine usage, such data are of immense importance. This study addresses age-stratified IgG titers and its subtypes in Pune, India, endemic for the disease.

Disease-duration based comparison of subsets of immune cells in SARS CoV-2 infected patients presenting with mild or severe symptoms identifies prognostic markers for severity.

Introduction: Infection with SARS-CoV-2 leads to a spectrum of symptoms. Understanding the basis for severity remains crucial for better management and therapy development. So far, older age, associated-comorbidities, and IL-6 have been associated with severity/mortality.

Anti-SARS-CoV-2 IgG antibody response among Indian COVID-19 patients using β-propiolactone-inactivated, whole virus-based indirect ELISA.

Background: Coronavirus disease 2019 (COVID-19) pandemic caused by infection with severe acute respiratory syndrome - coronavirus-2 (SARS-CoV-2) continues to affect many countries and large populations. Serologic assays for antibody detection aid patient diagnosis and seroepidemiologic investigations.

Methods: An indirect IgG ELISA was developed indigenously using β-propiolactone (BPL) inactivated SARS-CoV-2.