Oral rehydration salts, zinc supplement and rota virus vaccine in the management of childhood acute diarrhea

Explorations on the antiviral potential of zinc and magnesium salts against chikungunya virus: implications for therapeutics

Background

Chikungunya virus (CHIKV), which causes chikungunya fever, is an arbovirus of public health concern with no approved antiviral therapies. A significant proportion of patients develop chronic arthritis after an infection. Zinc and magnesium salts help the immune system respond effectively against viral infections. This study explored the antiviral potential of zinc sulphate, zinc acetate, and magnesium sulphate against CHIKV infection.

Methods

The highest non-toxic concentration of the salts (100 µM) was used to assess the prophylactic, virucidal, and therapeutic anti-CHIKV activities. Dose-dependent antiviral effects were investigated to find out the 50% inhibitory concentration of the salts. Entry bypass assay was conducted to find out whether the salts affect virus entry or post entry stages. Virus output in all these experiments was estimated using a focus-forming unit assay, real-time RT-PCR, and immunofluorescence assay.

Results

Different time- and temperature-dependent assays revealed the therapeutic antiviral activity of zinc and magnesium salts against CHIKV. A minimum exposure of 4 hours and treatment initiation within 1 to 2 hours of infection are required for inhibition of CHIKV. Entry assays revealed that zinc salt affected virus-entry. Entry bypass assays suggested that both salts affected post-entry stages of CHIKV. In infected C57BL6 mice orally fed with zinc and magnesium salts, a reduction in viral RNA copy number was observed.

Conclusion

The study results suggest zinc salts exert anti-CHIKV activity at entry and post entry stages of the virus life cycle, while magnesium salt affect CHIKV at post entry stages. Overall, the study highlights the significant antiviral potential of zinc sulphate, zinc acetate, and magnesium sulphate against CHIKV, which can be exploited in designing potential therapeutic strategies for early treatment of chikungunya patients, thereby reducing the virus-associated persistent arthritis.

Acute gastroenteritis-related acute kidney injury in a tertiary care center

BACKGROUND

Acute gastroenteritis (AGE) can cause acute kidney injury (AKI) via hypoperfusion mechanisms. Early detection of AKI caused by AGE can significantly decrease mortality rates. In Saudi Arabia, studies investigating the association between AGE and AKI are limited; thus, we aimed to fill this knowledge gap.

OBJECTIVES

Analyze all cases of AGE reported in tertiary-care hospitals to assess the prevalence of AKI among AGE patients.

DESIGN

Retrospective cohort SETTINGS: Single tertiary-care center PATIENTS AND METHODS: The study included patients treated for AGE between October 2017 and October 2022. Stool culture was used to diagnose AGE. Inclusion criteria were infective diarrhea and/ or vomiting, and availability of data (demographics, comorbidities, malignancies, length of hospital stay, vital signs at the time of diagnosis, dehydration, causative agents of diarrhea, hemodialysis status, and laboratory data.

MAIN OUTCOME MEASURES

Prevalence of AKI among AGE patients and factors associated with development of AKI.

SAMPLE SIZE

300 patients diagnosed with AGE.

RESULTS

Of the 300 patients with AGE, 41 (13.6%) had AKI, those older than 60 years were more likely to develop AKI. The most frequent cause of AGE was Salmonella spp. (n=163, 53.3%), whereas AKI was most common in Clostridium difficile AGE patients (n=21, 51.2%). Furthermore, the most common comorbidity in the present study was malignancy, especially leukemia and lymphoma the risk of AKI was independently associated with mild dehydration, higher serum urea concentrations and low GFR values.

CONCLUSIONS

Patients hospitalized for diarrheal disease are at an increased risk of developing AKI due to dehydration and comorbid conditions. It is crucial to keep kidney function in mind for AGE patients as this is associated with a high mortality rate and poor prognosis.

LIMITATIONS

The main limitation of this study was its retrospective design. Another limitation is that it is limited to a single center.

CONFLICTS OF INTEREST

None.

Predicting the long-term impact of rotavirus vaccination in 112 countries from 2006 to 2034: A transmission modeling analysis

Rotavirus vaccination has been shown to reduce rotavirus burden in many countries, but the long-term magnitude of vaccine impacts is unclear, particularly in low-income countries. We use a transmission model to estimate the long-term impact of rotavirus vaccination on deaths and disability adjusted life years (DALYs) from 2006 to 2034 for 112 low- and middle-income countries. We also explore the predicted effectiveness of a one- vs two- dose series and the relative contribution of direct vs indirect effects to overall impacts. To validate the model, we compare predicted percent reductions in severe rotavirus cases with the percent reduction in rotavirus positivity among gastroenteritis hospital admissions for 10 countries with pre- and post-vaccine introduction data. We estimate that vaccination would reduce deaths from rotavirus by 49.1 % (95 % UI: 46.6-54.3 %) by 2034 under realistic coverage scenarios, compared to a scenario without vaccination. Most of this benefit is due to direct benefit to vaccinated individuals (explaining 69-97 % of the overall impact), but indirect protection also appears to enhance impacts. We find that a one-dose schedule would only be about 57 % as effective as a two-dose schedule 12 years after vaccine introduction. Our model closely reproduced observed reductions in rotavirus positivity in the first few years after vaccine introduction in select countries. Rotavirus vaccination is likely to have a substantial impact on rotavirus gastroenteritis and its mortality burden. To sustain this benefit, the complete series of doses is needed.

Statins significantly repress rotavirus replication through downregulation of cholesterol synthesis

Rotavirus is the most common cause of severe diarrhea among infants and young children and is responsible for more than 200,000 pediatric deaths per year. There is currently no pharmacological treatment for rotavirus infection in clinical activity. Although cholesterol synthesis has been proven to play a key role in the infections of multiple viruses, little is known about the relationship between cholesterol biosynthesis and rotavirus replication. The models of rotavirus infected two cell lines and a human small intestinal organoid were used. We investigated the effects of cholesterol biosynthesis, including inhibition, enhancement, and their combinations on rotavirus replication on these models. The knockdown of 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) was built by small hairpin RNAs in Caco2 cells. In all these models, inhibition of cholesterol synthesis by statins or HMGCR knockdown had a significant inhibitory effect on rotavirus replication. The result was further confirmed by the other inhibitors: 6-fluoromevalonate, Zaragozic acid A and U18666A, in the cholesterol biosynthesis pathway. Conversely, enhancement of cholesterol production increased rotavirus replication, suggesting that cholesterol homeostasis is relevant for rotavirus replication. The effects of all these compounds toward rotavirus were further confirmed with a clinical rotavirus isolate. We concluded that rotavirus replication is dependent on cholesterol biosynthesis. To be specific, inhibition of cholesterol synthesis can downregulate rotavirus replication; on the contrary, rotavirus replication is upregulated. Statin treatment is potentially an effective novel clinical anti-rotavirus strategy.

Knowledge and attitude regarding rotavirus and its vaccination among medical students in Karachi, Pakistan

Objective

The aim of this study is to determine the knowledge and attitude regarding rotavirus and its vaccination among medical students.

Study design

It is a cross sectional study.

Methods

Total 324 medical students were selected through stratified random sampling. A structured and validated questionnaire was used. Knowledge and attitude were recorded on scale. Independent t-test and ANVOA was used to determine the difference among gender and academic year. Regression and correlation analysis was done to determine the correlation of knowledge and attitude level with age and academic year of study. p value≤0.05 considered as statistically significant.

Results

Mean and standard deviation score of students were 7.88 ± 2.46 on knowledge scale and 4.16 ± 1.23 on attitude scale. Total 87% of students were aware of rotavirus and its vaccination. Both knowledge and attitude level were increased significantly with increasing year of study and age. After adjustment of covariate, Age and academic year of study were the significant factors in determining the scores on knowledge scale. (beta coefficient 0.056 with p-value 0.003 and 0.433 with p-value-0.000).

Conclusion

Medical students were appropriate knowledge about the rotavirus but attitude toward rotavirus vaccination is unsatisfactory. It should be a part of the curriculum of not just medical students but all students from high school to undergrad level regardless of the course they are enrolled in and also be advertised by the government.

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Medical students were appropriate knowledge about the rotavirus but attitude toward rotavirus vaccination is unsatisfactory.

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Age and academic year of study were the significant factors in determining the scores on knowledge scale.

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Rotavirus virus vacciantion and its importance should be a part of curriculum of all secondary students.

Strain-Specific Probiotic Properties of Bifidobacteria and Lactobacilli for the Prevention of Diarrhea Caused by Rotavirus in a Preclinical Model

Probiotic supplementation with different lactobacilli and bifidobacterial strains has demonstrated beneficial effects in infectious diarrhea caused by rotavirus (RV) in young children. Preclinical models of RV infection might be a good strategy to screen for the efficacy of new probiotic strains or to test their comparative efficacy. Neonatal Lewis rats were supplemented with Bifidobacterium breve M-16V, Lactobacillus acidophilus NCFM, Lactobacillus helveticus R0052, or Lactobacillus salivarius PS2 from days 2–14 of life. On day five, animals received RV SA-11 orally. Fecal samples were collected daily, weighed, and scored for the calculation of severity and incidence of diarrhea. In addition, fecal pH and fecal viral shedding were measured. Animals were sacrificed at the end of the study and their blood was obtained for the quantification of RV-specific immunoglobulins. RV infection was induced in ~90% of the animals. All probiotics caused a reduction of several clinical variables of severity and incidence of diarrhea, except L. salivarius PS2. L. acidophilus NCFM, B. breve M-16V, and L. helveticus R0052 seemed to be very effective probiotic strains. In addition, all Lactobacillus strains reduced the viral elimination one day post-inoculation. No differences were detected in the specific anti-RV humoral response. The present study highlights the strain-specific effects of probiotics and identifies promising probiotics for use in ameliorating and preventing RV-induced diarrhea in children, for example by including them in infant formulas.

Conformational analysis of Pneumococcal Surface Antigen A (PsaA) upon zinc binding by fluorescence spectroscopy

PsaA (pneumococcal surface antigen A) is a S. pneumoniae virulence factor that belongs to the metal transport system. The Manganese PsaA binding has been associated with oxidative stress resistance becoming a pivotal element in the bacteria virulence. It has been shown that Zinc inhibits the Manganese acquisition and promotes bacteria toxicity. We have performed a PsaA conformational analysis both in the presence (Zn-rPsaA) and in the absence of Zinc (free-rPsaA). We performed experiments in the presence of different Zinc concentrations to determine the metal minimum concentration which induced a conformational change. The protein in free and Zn-binding condition was also studied in pH ranging 2.6-8.0 and in temperature ranging 25oC-85oC. pH experiments showed a decrease of fluorescence intensity only in acidic medium. Analysis of the heat-induced denaturation demonstrated that Zinc-binding promoted an increase in melting temperature from 55oC (free-rPsaA) to 78.8oC (Zn-rPsaA) according to fluorescence measurements. In addition, the rPsaA stabilization by Zinc was verified through analysis of urea and guanidine hydrochloride denaturation. Data showed that Zinc promoted an increase in the rPsaA stability and its removal by EDTA can lead to a PsaA intermediate conformation. These findings can be considered in the development of vaccines containing PsaA as antigen.

Unusual rotavirus genotypes among children with acute diarrhea in Saudi Arabia

Background

Human rotavirus A (human RV-A) is the most common cause of viral gastroenteritis in infants. The objective of the study was to characterize the G and P genotypes among clinical rotavirus isolates from children with acute diarrhea admitted to a tertiary care hospital in Riyadh, Saudi Arabia.

Methods

From 2011 to 2012, 541 pediatric patients with acute diarrhea were tested for rotavirus infection. RNA extractions from the fecal specimens were done by commercial kit. RT-PCR and sequencing techniques were used to detect the prevalent genotypes. Phylogenetic analysis by Maximum Likelihood method was used to study the clustering of the circulating genotypes.

Results

The data showed that 171/541 (31.6%) faecal samples were positive for human RVA and majority were children aged below 2 years. From the G and P [types] detected it was seen that (a) 171 minus 43 ie. 128 rotavirus positives were G typed successfully (b) 171 minus 20 ie. 151 rotavirus positives were P typed successfully; (c) overall G [P] nature was determined for 113 rotavirus positives out of 171. VP4 genotyping showed that majority of the positives 146/151 (96.7%) were P [8]; 4/151 (2.6%) were P [4]; 1/151 (0.66%) was P [6]. The dominant strains included G1P [8] 70/113 (61.9%); G9P [8] 19/113 (16.8%); G12P [8] 7/113 (6.2%) and G3P [8] 5/113 (4.4%) while the uncommon strains detected from Saudi Arabia during the study were G1P [4] 1/113 (0.88%) and G12P [6] 1/113 (0.88%). Phylogenetic tree, based on VP4/VP7 sequence analysis, revealed that G1P [8] was distinctly related to homologous strains included in human RV-A vaccine strains. Nevertheless, the uncommon genotypes G1P [4] and G12P [6] were clustered with isolates from other countries such as Bangladesh, China, Japan, Thailand and Philippines.

Conclusions

More studies will be required to further focus on newly emerging genotypes in our region together with the seasonality of rotavirus infection in the region, especially after January 2013 when the rotavirus vaccination has become part of routine childhood immunizations.

Treating diarrhoeal disease in children under five: the global picture

Rates of childhood mortality due to diarrhoea remain unacceptably high and call for renewed global focus and commitment. Affordable, simple and effective diarrhoeal treatments have already been available for many years, yet a shift in international health priorities has seen coverage of recommended treatments slow to a near-standstill since 1995. This article reviews coverage of recommended childhood diarrhoeal treatments (low-osmolarity oral rehydration solution (ORS) and zinc), globally and regionally, and provides an overview of the major barriers to wide-scale coverage. It is argued that to ensure smooth supply and equitable distribution of ORS and zinc, adequate financing, relevant policy changes, strong public, private and non-government organisation (NGO) collaboration, local manufacturing of pharmaceuticals, mass media awareness and campaigning, in conjunction with strong government support, are necessary for successful treatment scale-up.

Diarrhea among children in developing countries

Diarrhea continues to stand among the most important causes of global morbidity and mortality in children under 5 years of age. Although the introduction of oral rehydration and other case-management strategies have reduced acute diarrhea fatalities, many of the survivors develop persistent diarrhea and/or deficiencies of growth and cognition. Thus understanding the true global burden of diarrhea requires attention to acute diarrhea as well is its sequelae. To understand the etiology of moderate to severe diarrhea among children in high mortality areas of sub-Saharan Africa and south Asia we performed a comprehensive case-control study of children under 5 years of age at seven sites. Each site employed an identical case-control study design and each utilized a uniform comprehensive set of microbiological assays to identify the likely bacterial, viral and protozoal etiologies. Results of the studies will inform diarrhea prevention and management efforts worldwide.