Group A streptococci (GAS) are gram-positive, cocci-shaped bacteria that cause a wide variety of infections and are a cause of significant health burden, particularly in lower- and middle-income nations. The GAS genome contains a number of virulence factors such as the M-protein, hyaluronic acid, C5a peptidase, etc. Despite its significant health burden across the globe, a proper vaccine against GAS infections is not yet available. Various candidates for an effective GAS vaccine are currently being researched. These are based on various parts of the streptococcal genome. These include candidates based on the N-terminal region of the M protein, the conserved C-terminal region of the M protein, and other parts of the streptococcal genome. The development of a vaccine against GAS infections is hampered by certain challenges, such as extensive genetic heterogeneity and high protein sequence variation. This review paper sheds light on the various virulence factors of GAS, their epidemiology, the different vaccine candidates currently being researched, and the challenges associated with M-protein and non-M-protein-based vaccines. This review also sheds light on the current scenario regarding the status of vaccine development against GAS-related infections.
3 November 2021 in The American Journal of Tropical Medicine and Hygiene
We conducted a nationally representative population-based survey in 60 districts from 15 Indian states covering all five geographic regions during 2017–2018 to estimate the age specific seroprevalence of dengue. Of the 12,300 sera collected, 4,955 were positive for IgG antibodies against dengue virus using IgG Indirect ELISA indicating past dengue infection. We tested 4,948 sera (seven had inadequate volume) positive for IgG antibodies on indirect ELISA using anti-dengue IgG capture ELISA to estimate the proportion of dengue infections with high antibody titers, suggestive of acute or recent secondary infection. Of the 4,948 sera tested, 529 (10.7%; 95% CI: 9.4–12.1) were seropositive on IgG capture ELISA. The proportions of dengue infections with high titers were 1.1% in the northeastern, 1.5% in the eastern, 6.2% in the western, 12.2% in the southern, and 16.7% in the northern region. The distribution of dengue infections varied across geographic regions, with a higher proportion of infections with high antibody titer in the northern and southern regions of India. The study findings could be useful for planning facilities for clinical management of dengue infections.
14 June 2024 in Journal of Family Medicine and Primary Care
Introduction: The most reliable indicator for anaemia diagnosis at the population level is haemoglobin (Hb) estimation. The direct cyanmethaemoglobin method is considered the gold standard method for haemoglobin estimation. However, for resource constraint areas like primary health care (PHC) level, either blood samples are transported on filter paper for Hb testing (indirect cyanmethaemoglobin method) in laboratory or point of care testing is commonly used. Therefore, a comparative analysis of haemoglobin estimation of direct with indirect cyanmethaemoglobin method and also with TrueHb (Wrig Nanosystems Pvt. Ltd.) haemometer was done to strengthen anaemia diagnosis at the PHC level. Materials and Methods: This was a cross-sectional study. A total of 90 participants above 9 years of age, who visited the outpatient department (OPD) of health centre, Kheri and gave consent were included. Comparative analysis was done between Hb concentration assessed by indirect cyanmethaemoglobin method and TrueHb haemometer device against the gold standard method. Results: The mean Hb value estimated by direct method, TrueHb haemometer and indirect methods (filter paper A, B and C) was 11.42 ± 1.59 g/dl, 11.52 ± 1.54 g/dl, 10.66 ± 1.52 g/dl, 9.84 ± 1.50 g/dl and 10.19 ± 1.62 g/dl, respectively. There was no significant difference found between the mean Hb concentration estimated by the direct method and the TrueHb haemometer device. However, there was a significant difference in mean Hb values between the direct method and the indirect method. Therefore, regression analysis was done to estimate the correction factor for the indirect method. Conclusion: TrueHb metre device gave promising results in comparison to the gold standard method and can be used if resource permits in PHC centres. Indirect methods of haemoglobin estimation can be an alternative in resource-constraint settings, specifically for surveys. However, further studies are required for the validation of the indirect method.
21 December 2023 in Journal of Family Medicine and Primary Care
Background: Rheumatic heart disease/Rheumatic fever is a non – communicable disease being a major neglected health problem. Recurrent attacks of rheumatic fever can have catastrophic outcomes, therefore regular administration of antibiotics is recommended. During COVID 19 pandemic, people were afraid to approach hospitals hence the compliance and follow up of patients were affected. This study had planned to assess the treatment adherence of patients diagnosed with rheumatic fever/rheumatic heart disease during COVID 19 pandemic and to describe the socio demographic factors, clinical characteristics. This study also determines the factors associated with the treatment adherence. Methods: A cross sectional study was conducted among Rheumatic Fever/Rheumatic Heart Disease patients, attending Outpatient department at tertiary care hospital during COVID 19 pandemic. Mean score with confidence interval was calculated for quantitative data. P value less than 0.05 is significant. Results: The Mean (SD) age of the study participants was 41 ± 14.17 years. Treatment adherence was found to be 94.5 percent among Rheumatic Fever/Rheumatic Heart Disease patients during COVID 19 pandemic. 89.5% of injection benzathine penicillin users had an adherence rate above 80 percent. It was found that the presence of comorbidities (Diabetes/Hypertension/both Diabetes and Hypertension) had a statistically significant association with treatment adherence. Conclusions: Rheumatic Heart Disease is a disease of young and middle -age population affecting predominantly females. The overall adherence rate among Rheumatic Fever/Rheumatic Heart Disease patients was high. High time to maintain hospital-based registry to have follow up of patients.
1 July 2014 in International Journal of Medical Microbiology
Real-time RT-PCR is used as a gold standard method for the diagnosis of COVID-19. Since real-time RT PCR is nucleic acid-based, it is a highly sensitive and specific test. However, this test takes 4–8 h to generate results and, in emergency settings, this delay may prove fatal for certain patients. The frequent surge in COVID cases increases patient load in emergency settings. Thus, a nucleic acid-based rapid POC test is required that can generate results quickly as well as being comparable to real-time RT-PCR. In this study, comparison of real-time RT-PCR was carried out using the rapid nucleic acid-based LAMP method. Nasopharyngeal swabs were taken in duplicate from patients visiting the kiosk and were analyzed for the presence of the SARS-CoV-2 virus by both real-time RT-PCR and LAMP techniques ID NOW(bbott). Out of 14 positive and 31 negative samples tested by real-time RT-PCR, 13 samples were identified as positive and 31 were observed as negative with the LAMP-based test. Hence, the sensitivity and specificity of this method were found to be 92.9% and 93.5%, respectively. Therefore, LAMP-based point-of-care testing has the potential to be used in hospital emergency settings for quick diagnosis of critically ill patients, and the information generated here will further draw the attention of policymakers toward such nucleic acid-based rapid tests.