RESUMEN
Influenza virus is a well-known pathogen that can cause epidemics and pandemics. Several surveillance methods are being followed to monitor the transmission patterns and spread of influenza in the community. Wastewater-based Epidemiology (WBE) can serve as an additional tool to detect the presence of influenza viruses. The current study primarily focuses on surveillance of Influenza A and Influenza B in wastewater treatment plant (WWTP) samples. A total of 100 wastewater samples were collected in July (n = 50) and August (n = 50) 2023 from four different WWTPs in Manipal and Udupi, district of Karnataka, India. The WWTP samples were processed and tested by Real-Time reverse transcriptase PCR (RT-PCR). The data generated was analysed in comparison with the clinical Influenza cases. Of the 100 samples, 18 (18%) tested positive for Influenza A virus and 2 (2%) tested positive for Influenza B virus, with a viral load ranging 1.4 x 102-2.2 x 103 gc/L for influenza A virus and 5.2 x 103-7.7 x 103gc/L for influenza B virus. On correlating the WWTP positivity with clinical case, it was found that influenza clinical cases and virus positivity in wastewater increased simultaneously, emphasizing WBE as a concurrent method for monitoring influenza virus activity.
Asunto(s)
Hospitales , Virus de la Influenza A , Virus de la Influenza B , Gripe Humana , Aguas Residuales , Aguas Residuales/virología , Virus de la Influenza B/aislamiento & purificación , Virus de la Influenza B/genética , Virus de la Influenza A/genética , Virus de la Influenza A/aislamiento & purificación , Humanos , India/epidemiología , Gripe Humana/virología , Gripe Humana/epidemiología , Purificación del Agua , Carga Viral , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
Background: Dengue virus (DENV) infection is an important public health problem and causes significant morbidity and mortality. DENV typically causes a febrile illness that ranges from mild asymptomatic infection to fatal dengue hemorrhagic fever (DHF) and/or dengue shock syndrome (DSS). Early prediction of severe dengue disease is of utmost importance for providing prompt monitoring and treatment. The search for an ideal biomarker (host or viral factors) for early prediction of severe dengue remains elusive. Aim: To standardize a real time qRT-PCR for quantifying dengue viremia in serum samples and evaluate the kinetics of dengue viremia and its significance in disease severity. Results: In this ambispective study of 126 laboratory confirmed dengue patients, 72 were primary infections and 54 were secondary infections. The most common serotype was serotype 1 (n = 37) followed by serotype 2 (n = 34). According to WHO 1997 dengue case classification, 111 patients were cases of dengue fever (DF), 13 from DHF and 02 from DSS. Day 3 viremia levels were significantly elevated in severe dengue patients (DHF/DSS) as compared to that of DF (p < 0.05). However, no such association was found between viremia levels and serotype or immune status. Conclusion: Dengue viremia has a significant association with disease severity and day 3 viremia levels may be used as a predictor for dengue disease severity.
RESUMEN
BACKGROUND OBJECTIVES: Scrub typhus is clinically undifferentiated from other aetiologies for acute febrile illness such as enteric fever, dengue, malaria, and leptospirosis. Rapid ELISA tests are being used as an alternative to immunofluorescence assay in tropical countries. METHODS: In this study, we compared and evaluated commercially available InBios Scrub Typhus Detect IgM Rapid Test (USA) for diagnosing human scrub typhus infection using archived and prospectively collected samples against the reference standard, InBios Scrub Typhus Detect IgM ELISA (USA). RESULTS: The data analysis of archived samples on rapid test revealed a moderate sensitivity of 53.92% and a specificity of 100%. Meanwhile, prospective serum samples demonstrated higher sensitivity and specificity of 96.4% and 94.6%, respectively. INTERPRETATION CONCLUSION: The InBios Scrub Typhus Detect IgM rapid test can be a good point-of-care assay during surveillance, outbreak investigations, and case identification.
RESUMEN
The immunopathogenesis of dengue severity is convoluted. The primary objective of the research was to examine the dynamics of cytokine storm and its correlation with disease development in individuals affected by DENV infection. Additionally, the study aimed to discover potential biomarkers that could indicate severe dengue infection and determine the most suitable timeframe for predicting the severity of these biomarkers during the acute stage of dengue infections. We conducted a temporal analysis of the daily viral load and cytokine levels in 60 hospitalized dengue patients until discharge. Our findings reveal a distinct cytokine profile (elevated IL-8, IL-10, IL-6, GM-CSF, MCP-1, IL-13, and IL-4 and decreased IL-12, MIP-1ß) on the third day after symptom onset is predictive of severe dengue in secondary dengue infection. The imbalanced cytokine signature may inform clinical decision-making in treating severe dengue infections.
Asunto(s)
Virus del Dengue , Dengue , Dengue Grave , Humanos , Síndrome de Liberación de Citoquinas , Citocinas , BiomarcadoresRESUMEN
Background: Chikungunya disease (CHIKD) is a threat to global health, as it impairs the quality of life of an infected individual ranging from months to years. A systematic evaluation of the serological, virological, and immunological aspects of the circulating viruses and their impact on the host response is imperative for better understanding of the evolving disease dynamics. Methods: Serum samples were collected from 196 acute CHIKD patients from ten tertiary care hospitals across India during 2016-2021. Out of 196 patients, paired convalescent samples were collected from 51 patients (one-month post-onset of symptoms). The serum samples were profiled for cytokines and neutralisation capacity. Further, chikungunya virus (CHIKV) was isolated from the acute sera and the replication kinetics of the clinical isolates was evaluated. Findings: Serological analysis indicated that neutralisation could be correlated to seroconversion in the convalescent phase but not found significant in acute phase. In the acute phase samples, there was a correlation between elevated serum levels of IFN-γ, IP-10, MCP-1 and MIG and disease severity. During convalescent phase, pro-inflammatory markers such as IL-6, IL-1ß, IL-9 and IP-10 were found to be elevated with a corresponding decline in the secretion of anti-inflammatory cytokines such as IL-4 and IL-10, which correlated with persistent arthralgia. Analysis of replication of the clinical isolates revealed that 68.4% of viruses were fast-growing in the Vero cells (cytopathic effect [CPE] observed within 24 h post-infection), and their corresponding acute serum samples showed an elevated secretion of IFN-α, IL-1RA, IL-17F, IL-9, MCP-1 and MIP-1α. Interpretation: This study provides an important overview of neutralisation capabilities and cytokine responses along with virus pathogenesis associated with CHIKV infections in India. Funding: Biotechnology Industry Research Assistance Council (BIRAC).
RESUMEN
The spotted fever group (SFG) of Rickettsia are zoonotic disease-causing pathogens, commonly transmitted by hard ticks to a wide range of hosts, including humans. Rickettsia conorii is the common SFG recognised in India, whereas most of the infections due to other group species go undifferentiated at the species level. Hence, this study was conducted to screen host-seeking ticks in the Western Ghats region, India, for the DNA of SFG Rickettsia. The ticks were collected from Kerala, Goa, and Maharashtra states of India during a survey conducted between November 2017 and January 2018. In total, 288 tick pools were screened for Rickettsia spp. DNA using pan-Rickettsia real-time PCR, and conventional PCR targeting the gltA, OmpA and 17-kDa protein-coding genes. Nucleotide sequences were subjected to phylogenetic analysis using the NCBI BLAST tool to identify submitted sequences with higher homology. Neighbour-joining trees were constructed using the reference sequences of the GenBank database. Overall, Rickettsia spp. DNA was detected in 27.2% (62/228 pools) of host-seeking ticks across the Western Ghats region, with an estimated minimum infection rate of 0.057. Upon phylogenetic analysis, it was identified that the detected sequences were highly similar (> 99% sequence homology) to R. africae, Candidatus R. laoensis and an un-categorised Rickettsia species, and they were widely carried by Haemaphysalis ticks. The current study is the first report of R. africae and Candidatus R. laoensis in ticks in India. Although the pathogenicity of these species is not well documented, they may pose a potential threat to both animal and the human population in this geographical region.
Asunto(s)
Ixodidae , Rickettsia , Rickettsiosis Exantemáticas , Garrapatas , Animales , Humanos , Garrapatas/microbiología , Filogenia , India , Rickettsia/genética , Ixodidae/microbiología , Reacción en Cadena en Tiempo Real de la Polimerasa , Rickettsiosis Exantemáticas/epidemiología , Rickettsiosis Exantemáticas/veterinariaRESUMEN
Influenza viruses can mutate genetically and cause a range of respiratory ailments. The H275Y mutation in the neuraminidase (NA) gene reduces the effectiveness of oseltamivir, a widely used drug for the treatment of Influenza A and B virus infection. The World Health Organization (WHO) recommends single-nucleotide polymorphism assays to detect this mutation. The present study aims to estimate the prevalence of H275Y mutation conferring oseltamivir resistance in Influenza A(H1N1)pdm09 virus among hospitalized patients from June 2014 to December 2021. Following the WHO protocol, allelic discrimination real-time RT-PCR was performed for 752 samples. Out of the 752 samples, 1 tested positive for Y275 gene mutation by allelic discrimination real-time RT-PCR. In samples of years 2020 and 2021, neither the H275 nor Y275 genotype was detected. Sequencing of the NA gene of all negative samples showed a mismatch between the NA sequence and the probes used in the allelic discrimination assay. Also, Y275 mutation was detected in only 1 sample from 2020. The prevalence of oseltamivir resistance was estimated as 0.27% among the Influenza A(H1N1)pdm09 patients during 2014-2021. The study highlights that the WHO-recommended probes for detecting H275Y mutation may not be useful to detect 2020 and 2021 circulating strains of Influenza A(H1N1)pdm09, emphasizing the need for continuous monitoring of mutations in the influenza virus.
Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Virus de la Influenza A , Gripe Humana , Humanos , Oseltamivir/farmacología , Oseltamivir/uso terapéutico , Gripe Humana/tratamiento farmacológico , Gripe Humana/epidemiología , Antivirales/farmacología , Antivirales/uso terapéutico , Subtipo H1N1 del Virus de la Influenza A/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Mutación Missense , Mutación , Virus de la Influenza A/genética , Neuraminidasa/genética , Farmacorresistencia Viral/genéticaRESUMEN
Like the world over, Nepal was also hard hit by the second wave of COVID-19. We audited the clinical care provided to COVID-19 patients admitted from April to June 2021 in a tertiary care hospital of Nepal. This was a cohort study using routinely collected hospital data. There were 620 patients, and most (458, 74%) had severe illness. The majority (600, 97%) of the patients were eligible for admission as per national guidelines. Laboratory tests helping to predict the outcome of COVID-19, such as D-dimer and C-reactive protein, were missing in about 25% of patients. Nearly all (>95%) patients with severe disease received corticosteroids, anticoagulants and oxygen. The use of remdesivir was low (22%). About 70% of the patients received antibiotics. Hospital exit outcomes of most (>95%) patients with mild and moderate illness were favorable (alive and discharged). Among patients with severe illness, about 25% died and 4% were critically ill, needing further referral. This is the first study from Nepal to audit and document COVID-19 clinical care provision in a tertiary care hospital, thus filling the evidence gap in this area from resource-limited settings. Adherence to admission guidelines was excellent. Laboratory testing, access to essential drugs and data management needs to be improved.
RESUMEN
The COVID-19 pandemic and public health response to the pandemic has caused huge setbacks in the management of other infectious diseases. In the present study, we aimed to (i) assess the trends in numbers of samples from patients with influenza-like illness and severe acute respiratory syndrome tested for influenza and the number and proportion of cases detected from 2015−2021 and (ii) examine if there were changes during the COVID-19 period (2020−2021) compared to the pre-COVID-19 period (2015−2019) in three states of India. The median (IQR) number of samples tested per month during the pre-COVID-19 period was 653 (395−1245), compared to 27 (11−98) during the COVID-19 period (p value < 0.001). The median (IQR) number of influenza cases detected per month during the pre-COVID-19 period was 190 (113−372), compared to 29 (27−30) during the COVID-19 period (p value < 0.001). Interrupted time series analysis (adjusting for seasonality and testing charges) confirmed a significant reduction in the total number of samples tested and influenza cases detected during the COVID-19 period. However, there was no change in the influenza positivity rate between pre-COVID-19 (29%) and COVID-19 (30%) period. These findings suggest that COVID-19-related disruptions, poor health-seeking behavior, and overburdened health systems might have led to a reduction in reported influenza cases rather than a true reduction in disease transmission.
RESUMEN
Kyasanur Forest Disease (KFD) is a viral haemorrhagic fever, transmitted to humans and other hosts by a tick vector of genus Haemaphysalis. It affects 400-500 people annually in the Western Ghats region of India through spring to summer season. To understand the species composition, distribution, and abundance of Haemaphysalis ticks in endemic taluks (sub-districts) of India, a surveillance for ticks was conducted between October 2017 and January 2018. In total 105 sites were selected based on grid sampling from five taluks representing five KFD endemic states in south India. A sum of 8373 ticks were collected by using standard flagging method. The study showed a wide distribution of host seeking tick species among the selected taluks, wherein Haemaphysalis spinigera was predominant in 3/5 taluks, Haemaphysalis bispinosa in 1/5 taluks, and both the species in 1/5 taluks. Further, the H. spinigera abundance was categorised and compared with the incidence of human cases during the same season. The grids with very high and high H. spinigera abundance had 70% of the 205 human cases reported. This method of tick surveillance could be efficiently used as a standard model for KFD transmission risk assessment and prediction of impending outbreaks.
Asunto(s)
Distribución Animal , Ixodidae/fisiología , Enfermedad del Bosque de Kyasanur/epidemiología , Animales , Bosques , Humanos , Incidencia , India , PrevalenciaRESUMEN
BACKGROUND: Nipah virus (NiV) is 1 of 10 potential causes of imminent public health emergencies of international concern. We investigated the NiV outbreak that occurred in May 2018 in Kerala, India. Here we describe the longitudinal characteristics of cell-mediated and humoral immune responses to NiV infection during the acute and convalescent phases in 2 human survivors. METHODS: Serial blood samples were obtained from the only 2 survivors of the NiV outbreak in Kerala. We used flow cytometry to determine the absolute T-lymphocyte and B-lymphocyte counts and the phenotypes of both T and B cells. We also detected and quantitated the humoral immune response to NiV by virus-specific immunoglobulin M (IgM) and immunoglobulin G (IgG) enzyme-linked immunosorbent assay. RESULTS: Absolute numbers of T lymphocytes remained within normal limits throughout the period of illness studied in both survivors. However, a marked elevation of activated CD8 T cells was observed in both cases. More than 30% of total CD8 T cells expressed Ki67, indicating active proliferation. Proliferating (Ki-67+) CD8 T cells expressed high levels of granzyme B and PD-1, consistent with the profile of acute effector cells. Total B-lymphocyte, activated B-cell, and plasmablast counts were also elevated in NiV survivors. These individuals developed detectable NiV-specific IgM and IgG antibodies within a week of disease onset. Clearance of NiV RNA from blood preceded the appearance of virus-specific IgG and coincided with the peak of activated CD8 T cells. CONCLUSIONS: We describe for the first time longitudinal kinetic data on the activation status of human B- and T-cell populations during acute NiV infection. While marked CD8 T-cell activation was observed with effector characteristics, activated CD4 T cells were less prominent.