Non-immune Individuals Research Articles

Delayed haemolysis after treatment with intravenous artesunate in patients with severe malaria in India

BackgroundParenteral artesunate is the treatment of choice for severe malaria. It is safe, efficacious and well tolerated anti-malarial. However, delayed haemolysis has been reported in travellers, non-immune individuals and in African children.MethodsA prospective, observational study was carried out in admitted severe malaria patients receiving parenteral artesunate. The patients were followed up until day 28 for monitoring clinical as well as laboratory parameters for haemolytic anaemia.ResultsTwenty-four patients with severe malaria receiving injection artesunate were enrolled in the study. Post-artesunate delayed haemolysis following parenteral artesunate therapy was observed in three of 24 patients (12.5%, 95% confidence interval 4.5–31.2%). Haemolysis was observed in two more patients possibly due to other reasons. The haemoglobin fall ranged from 13.6 to 38.3% from day 7 to day 28 in these patients.ConclusionThe possibility of delayed haemolysis should be considered while treating the severe malaria patients with parenteral artesunate. The study highlights the need for further studies in different epidemiological settings.

Procalcitonin (PCT) Improves the Accuracy and Sensitivity of Dyspnea, Eosinopenia, Consolidation, Acidemia and Atrial Fibrillation (DECAF) Score in Predicting AECOPD Patients Admission to ICU.

The score of Dyspnea, Eosinopenia, Consolidation, Acidemia and Atrial Fibrillation (DECAF) can be used to predict the in-hospital mortality of patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). It is worth noting that the DECAF score is the first scoring standard combining biomarkers and clinical variables. The application of biomarkers is helpful for improving the accuracy of the scoring system. In recent years, more and more reports and studies paid attentions to procalcitonin (PCT) in respiratory infectious diseases and its clinical value has attracted increasing attention. The study aimed at investigating the effectiveness of the DECAF score combined with PCT in predicting admission of AECOPD patients to intensive care unit (ICU). We conducted a retrospective study. We analyzed data from 171 non-immune individuals over the age of 40 in this study. All patients received blood routine measurement and DECAF score calculation on admission. The primary outcome used to assess the probability of an AECOPD patient was who would get a bed in general ward or ICU. Receiver operating characteristic curves (ROC) are used to assess the sensitivity and specificity of PCT, WBC, creatinine, and DECAF scores in predicting the risk of admissions to the ICU of COPD patients. We combined PCT, WBC, and creatinine with DECAF scores, observing the sensitivity and specificity of the different combinations in predicting COPD patients with regard to who should be admitted to ICU. After analyzing the data from 171 patients, we found that the probability of entering the ICU was 21.05% (36/171). The area under curve (AUC) of PCT, WBC, creatinine, and DECAF score in individually predicting the probability of entering the ICU of AECOPD patients were 0.71 (95% CI 0.61 - 0.81), 0.64 (95% CI 0.52 - 0.75), 0.74 (95% CI 0.63 - 0.84), and 0.88 (95% CI 0.81 - 0.94), respectively, with statistically significant differences (p = 0.00). The sensitivities of PCT, WBC, creatinine and DECAF scores were 0.61, 0.61, 0.56, and 0.91, respectively. The specificities of PCT, WBC, creatinine, and DECAF scores were 0.76, 0.67, 0.88 and 0.74, respectively. The AUC of Combination 1 (PCT&DECAF scores), Combination 2 (WBC&DECAF scores), and Combination 3 (creatinine&DECAF scores) for predicting AECOPD patients entering the ICU was 0.92 (95% CI 0.86 - 0.97), 0.89 (95% CI 0.84 - 0.94), and 0.91 (95% CI 0.85 - 0.96), respectively, with statistically significant differences (p = 0.00); the sensitivities were 0.92, 0.86, and 0.94, respectively, and the specificities were 0.97, 0.78, and 0.74, respectively. Procalcitonin improves the accuracy and sensitivity of the DECAF score in predicting the probability of AECOPD patients entering the ICU, and PCT was superior to other indexes to improve the sensitivity and specificity of the DECAF score.

Underimmunization of the solid organ transplant population: An urgent problem with potential digital health solutions.

Solid organ transplant recipients are at risk for potentially life-threatening infections due to lifelong immunosuppression. Vaccine-preventable infections result in graft injury, morbidity, mortality, and significantly increased medical costs. Unfortunately, the majority of transplant recipients continue to be underimmunized at the time of transplant and thereafter. Given the rising rates of vaccine hesitancy and refusal in the general population, transplant recipients can no longer rely on herd immunity to protect them from vaccine-preventable infections. Novel tools are desperately needed to overcome transplant-specific immunization barriers to improve immunization rates in this high-risk population. Digital health technologies may offer a solution by addressing transplant-specific barriers: specifically, providing accurate information about vaccine safety, efficacy, and timing in the pre- and posttransplant periods; making a complete immunization record universally available and easily accessible; enabling communication between patients and multiple providers; and providing automated vaccine reminders to both patients and providers when vaccines are due using transplant-specific immunization guidelines. Digital health has transformed health care by empowering patients with their own health information and connecting patients, their providers, and public health officials. In doing so, it offers a potential platform to address and overcome the problem of underimmunization in the transplant population.

Can Complementary Prime-Boost Immunization Strategies Be an Alternative and Promising Vaccine Approach Against Dengue Virus?

Dengue is one of the most important diseases transmitted by mosquitoes. Dengvaxia®, a vaccine registered in several countries, cannot be administered to non-immune individuals and children younger than 9 years old, due to safety reasons. There are two vaccine candidates in phase 3 efficacy trials, but their registration date is completely unknown at this moment. So, the development of new vaccines or vaccine strategies continues to be a priority for the WHO. This work reviews some complementary prime-boost immunization studies against important human pathogens. Additionally, it reviews the results obtained using this regimen of immunization against dengue virus as a potential alternative approach for finding a safe and efficient vaccine. Finally, the main elements associated with this strategy are also discussed. The generation of new strategies of vaccination against dengue virus, must be directed to reduce the risk of increasing viral load through sub-neutralizing antibodies and it must be also directed to induce a polyfunctional T cell response. Complementary prime-boost immunization strategies could emerge as an interesting approach to induce solid immunity or at least to reduce viral load after natural infection, avoiding severe dengue. Subunit vaccine could be safe and attractive antigens for this strategy, especially proteins including B, and T-cells epitopes for inducing humoral and cellular immune responses, which can play an important role controlling the disease.

Central Nervous System Infection with Histoplasma capsulatum.

Histoplasmosis is an endemic fungal infection that may affect both immune compromised and non-immune compromised individuals. It is now recognized that the geographic range of this organism is larger than previously understood, placing more people at risk. Infection with Histoplasma capsulatum may occur after inhalation of conidia that are aerosolized from the filamentous form of the organism in the environment. Clinical syndromes typically associated with histoplasmosis include acute or chronic pneumonia, chronic cavitary pulmonary infection, or mediastinal fibrosis or lymphadenitis. Disseminated infection can also occur, in which multiple organ systems are affected. In up to 10% of cases, infection of the central nervous system (CNS) with histoplasmosis may occur with or without disseminated infection. In this review, we discuss challenges related to the diagnosis of CNS histoplasmosis and appropriate treatment strategies that can lead to successful outcomes.

Analyzing influenza outbreaks in Russia using an age-structured dynamic transmission model

In this study, we addressed the ability of a minimalistic SEIR model to satisfactorily describe influenza outbreak dynamics in Russian settings. For that purpose, we calibrated an age-specific influenza dynamics model to Russian acute respiratory infection (ARI) incidence data over 2009–2016 and assessed the variability of proportion of non-immune individuals in the population depending on the regarded city, the non-epidemic indicence baseline, the contact structure considered and the used calibration method. The experiments demonstrated the importance of distinguishing characteristics of different age groups, such as contact intensities and background immunity levels. It was also found that the current model calibration process, which relies mostly on ARI incidence, demonstrates notable variation of output parameter values. Employing additional sources of data, such as strain-specific influenza incidence and external assessments on underreporting levels in different age groups, might enhance the plausibility of parameter values obtained by model calibration, along with reducing the assessment variation.

Allocation to highly sensitized patients based on acceptable mismatches results in low rejection rates comparable to nonsensitized patients.

Whereas regular allocation avoids unacceptable mismatches on the donor organ, allocation to highly sensitized patients within the Eurotransplant Acceptable Mismatch (AM) program is based on the patient's HLA phenotype plus acceptable antigens. These are HLA antigens to which the patient never made antibodies, as determined by extensive laboratory testing. AM patients have superior long‐term graft survival compared with highly sensitized patients in regular allocation. Here, we questioned whether the AM program also results in lower rejection rates. From the PROCARE cohort, consisting of all Dutch kidney transplants in 1995‐2005, we selected deceased donor single transplants with a minimum of 1 HLA mismatch and determined the cumulative 6‐month rejection incidence for patients in AM or regular allocation. Additionally, we determined the effect of minimal matching criteria of 1 HLA‐B plus 1 HLA‐DR, or 2 HLA‐DR antigens on rejection incidence. AM patients showed significantly lower rejection rates than highly immunized patients in regular allocation, comparable to nonsensitized patients, independent of other risk factors for rejection. In contrast to highly sensitized patients in regular allocation, minimal matching criteria did not affect rejection rates in AM patients. Allocation based on acceptable antigens leads to relatively low‐risk transplants for highly sensitized patients with rejection rates similar to those of nonimmunized individuals.

Pathophysiology and Treatment of Hepatitis B and C Infections in Patients With End-Stage Renal Disease.

An in-depth understanding of viral hepatitis is important to the care of patients with end-stage renal disease undergoing hemodialysis. Both hepatitis B and C viruses are acquired through hematogenous spread and can lead to horizontal transmission. Concurrent hepatic and renal injuries have ominous outcomes with significant morbidity. Hepatitis B incidence has decreased through practices including vaccination of nonimmune individuals and isolation of patients with the disease. The pathogenesis of hepatitis B leads to various symptoms and serologic changes with unique temporal associations dictating an acute or chronic presentation. Chronic hepatitis B develops when there is persistence of surface antigen for more than 6months. Occult hepatitis B is an enigmatic form of the chronic disease where viral DNA is present despite the patient remaining seronegative. Nucleoside analogs are used as a treatment for individuals with hepatitis B who have comorbid CKD; however, the mainstay of infection control relies on immunization. Hepatitis C, an RNA virus, has increased in prevalence. Strict universal precautions with sound infection-control practices are important to prevent seroconversion. Recent therapeutic advances involving the development of direct-acting antiviral agents have broadened treatment options for patients with renal impairment and hepatitis C, offering the potential for a definitive cure. Controversy on the timeliness of treatment for transplant options has also risen with the advent of these newer therapies. We review the epidemiology, pathophysiology, and updates in treatment of these viral entities as they relate to the hemodialysis population.

Neutrophil-to-Lymphocyte Ratio Improves the Accuracy and Sensitivity of Pneumonia Severity Index in Predicting 30-Day Mortality of CAP Patients.

The pneumonia severity index (PSI) scoring system is one of the tools used to evaluate and predict the prognosis of patients with community-acquired pneumonia (CAP). Although PSI has been widely used in clinical studies of pneumonia, it is still rare to combine it with blood indexes to predict the prognosis of pneumonia. Neutrophil-to-lymphocyte ratio (NLR) is a promising candidate predictor of mortality in CAP patients. The aim of this study was to investigate the efficacy of pneumonia severity index combined with NLR in predicting 30-day mortality in CAP patients. We conducted a retrospective study. We analyzed data on 400 non-immune individuals over the age of 18 in this study. All patients received blood routine measurement and PSI score calculation after admission. The primary outcome measures were mortality and survival in CAP patients. The sensitivity and specificity of PSI score, NLR, and the combination of PSI score and NLR in predicting 30-day mortality were assessed using the subject operating characteristic curve (ROC). Data from 400 patients were analyzed, in which the 30-day mortality was 10.5% (42/400). The AUC of NLR and PSI in predicting 30-day mortality of CAP patients were 0.81 (95% CI 0.73 - 0.89) and 0.94 (95% CI 0.90 - 0.98), respectively, with statistically significant differences (p = 0.00). The sensitivity and specificity of NLR were 0.80 and 0.7, respectively. The sensitivity and specificity of PSI were 0.78 and 0.94, respectively. The combined AUC of the two indicators for predicting death in CAP patients was 0.95 (95% CI 0.92 - 0.99), and the sensitivity and specificity were 0.85 and 0.94, respectively. Neutrophil-to-lymphocyte ratio improves the accuracy and sensitivity of the pneumonia severity index in predicting 30-day mortality of CAP patients.

2479. Varicella Zoster Immune Globulin Is Effective up to 10 Days Following Varicella Exposure in Pregnant Women, Immunocompromised Patients, and Infants: Results From a Large, Open-Label Expanded-Access Program

BackgroundThere are more than 300,000 cases of varicella annually; nonimmune individuals exposed to varicella-zoster (VZ) virus have a high likelihood of developing varicella. VZ immune globulin (VARIZIG®) is used for postexposure prophylaxis to prevent or attenuate VZ infection in high-risk individuals. We assessed varicella incidence and severity in high-risk subjects after administration of VZ immune globulin.MethodsThis open-label expanded-access program provided VZ immune globulin to physician-identified, high-risk subjects exposed to varicella. Subjects included immunocompromised children/adults, infants (including preterm infants, newborns whose mothers had VZ infection <5 days before or <2 days after delivery, and infants <1 year of age), and pregnant women. VZ immune globulin (125 IU/10 kg [up to 625 IU]) was administered intramuscularly, ideally ≤96 hours, but up to 10 days, postexposure. Incidence of varicella rash and severity (>100 pox, pneumonia, encephalitis) were assessed up to 42 days after administration.ResultsThe efficacy population (n = 505) included 263 immunocompromised subjects (32 adults, 231 pediatric), 137 pregnant women, and 105 infants. More than 97% of exposures fit the CDC definition. Varicella incidence was low in immunocompromised subjects (4.5%, n = 12/269), pregnant women (7.3%, n = 10/137), and infants (11.4%, n = 12/105) and was similar when comparing administration ≤ 96 hours vs. up to 10 days postexposure (6.2% vs. 9.4%, respectively). Of 34 subjects with varicella, 54% were exposed in the household; 5 were considered severe. Common adverse events were pyrexia (4%), neutropenia (3%), and headache (3%). There were no product-related deaths and only 1 serious adverse event (serum sickness) considered probably related to VZ immune globulin.ConclusionPostexposure administration of VZ immune globulin resulted in low rates of varicella in high-risk subjects, regardless of administration timing within 10 days postexposure. VZ immune globulin—which is FDA-approved, recommended by the CDC, and widely available—was well tolerated and safe in high-risk subjects.Disclosures M. Levin, Merck: Consultant and Scientific Advisor, Consulting fee and Research support. GlaxoSmithKline: Consultant and Scientific Advisor, Consulting fee and Research support. Saol Therapeutics: Consultant and Scientific Advisor, Consulting fee. J. Duchon, Saol Therapeutics: Consultant and Scientific Advisor, Consulting fee. G. K. Swamy, Saol Therapeutics: Consultant and Scientific Advisor, Consulting fee.

The optimal dose of disease-specific antibodies for post-exposure prophylaxis of measles and rubella in Australia: new guidelines recommended

ABSTRACTBackground: It is unclear whether recommended doses of intramuscular polyvalent immune globulin are optimal for both effectiveness and efficiency of disease prevention when administered post-exposure to measles and rubella.Methods: The peak concentration and decay of disease-specific antibodies after intramuscular dosing of polyvalent immune globulin in adults were modeled using published pharmacokinetic parameters and product disease-specific antibody concentrations. Models simulated dosing according to current Australian guidelines, then adjusted the dose in clinically relevant increments to estimate the optimal dose of disease-specific immunoglobulins for post-exposure prophylaxis of nonimmune individuals against measles and rubella. Optimal dosing assumed a target serum concentration of disease-specific antibodies of the correlate of protection plus a 10% margin of error at an incubation period.Results: Current Australian guidelines appeared to underdose a measles-naïve subpopulation. The optimal dose of measles-specific antibodies was 17.5 IU/kg assuming 75% bioavailability and 25.5 IU/kg assuming 50% bioavailability. Current Australian guidelines recommend 520 IU/kg rubella antibodies for an 80-kg individual. This model suggests that 13 IU/kg is more than sufficient.Conclusions: The recommended dose of intramuscular polyvalent immune globulin should be increased following measles exposure and decreased following rubella exposure for recommended subgroups. These models may be adapted for use internationally.

IFN-λ and microRNAs are important modulators of the pulmonary innate immune response against influenza A (H1N2) infection in pigs.

The innate immune system is paramount in the response to and clearance of influenza A virus (IAV) infection in non-immune individuals. Known factors include type I and III interferons and antiviral pathogen recognition receptors, and the cascades of antiviral and pro- and anti-inflammatory gene expression they induce. MicroRNAs (miRNAs) are increasingly recognized to participate in post-transcriptional modulation of these responses, but the temporal dynamics of how these players of the antiviral innate immune response collaborate to combat infection remain poorly characterized. We quantified the expression of miRNAs and protein coding genes in the lungs of pigs 1, 3, and 14 days after challenge with swine IAV (H1N2). Through RT-qPCR we observed a 400-fold relative increase in IFN-λ3 gene expression on day 1 after challenge, and a strong interferon-mediated antiviral response was observed on days 1 and 3 accompanied by up-regulation of genes related to the pro-inflammatory response and apoptosis. Using small RNA sequencing and qPCR validation we found 27 miRNAs that were differentially expressed after challenge, with the highest number of regulated miRNAs observed on day 3. In contrast, the number of protein coding genes found to be regulated due to IAV infection peaked on day 1. Pulmonary miRNAs may thus be aimed at fine-tuning the initial rapid inflammatory response after IAV infection. Specifically, we found five miRNAs (ssc-miR-15a, ssc-miR-18a, ssc-miR-21, ssc-miR-29b, and hsa-miR-590-3p)–four known porcine miRNAs and one novel porcine miRNA candidate–to be potential modulators of viral pathogen recognition and apoptosis. A total of 11 miRNAs remained differentially expressed 14 days after challenge, at which point the infection had cleared. In conclusion, the results suggested a role for miRNAs both during acute infection as well as later, with the potential to influence lung homeostasis and susceptibility to secondary infections in the lungs of pigs after IAV infection.

Retrospective observational study of the use of artemether-lumefantrine in the treatment of malaria in Japan.

The Research Group on Chemotherapy of Tropical Diseases, Japan, introduced artemether-lumefantrine (AL) in late 2002, mainly for treating uncomplicated Plasmodium falciparum malaria. Because AL was on the market in Japan in March 2017, the effectiveness and safety of AL were analyzed to help medical personnel use AL optimally. Case report forms submitted by the attending physicians were analyzed. When necessary, direct contact with the attending physicians was made to obtain detailed information. Effectiveness analysis was performed for 62 cases and safety analysis was performed for 66 cases. In P. falciparum malaria, the overall cure rate was 91.1% (51/56), of which the cure rates for Japanese and non-Japanese patients were 82.1% (23/28) and 100% (28/28), respectively. The successfully treated cases included severe P. falciparum malaria, with parasite densities exceeding 500,000/μL. Adverse events were reported in 14 patients, including delayed hemolytic anemia which occurred in the top four highest parasitemic cases. AL treatment failure in P. falciparum malaria may not be rare among non-immune individuals, including Japanese. The possibility of delayed hemolytic anemia, which occurs preferentially in high parasitemic cases, should be considered following AL treatment.

Testing for hepatitis B virus alone does not increase vaccine coverage in non-immunized persons.

AIMTo determine whether hepatitis B virus (HBV)-testing could serve as a gateway to vaccinate non-immunized individuals in a low-prevalent country.METHODSNon-immunized subjects participating in a multi-center, HBV-testing campaign in Paris, France were identified and contacted via telephone 3-9 mo after testing in order to determine vaccination status. Vaccination coverage was evaluated in per-protocol (for all respondents) and intent-to-treat analysis (assuming all non-responders did not vaccinate).RESULTSIn total, 1215/4924 (24.7%) enrolled subjects with complete HBV serology were identified as non-immunized and eligible for analysis. There were 99/902 successfully contacted subjects who had initiated HBV vaccination after screening: per-protocol, 11.0% (95%CI: 9.0-13.2); intent-to-treat, 8.2% (95%CI: 6.7-9.8). In multivariable analysis, vaccination was more likely to be initiated in individuals originating from moderate or high HBV-endemic countries (P < 0.001), patients with limited healthcare coverage (P = 0.01) and men who have sex with men (P = 0.02). When asked about the reasons for not initiating HBV vaccination, the most frequent response was “will be vaccinated later” (33.4%), followed by “did not want to vaccinate” (29.8%), and “vaccination was not proposed by the physician” (21.5%). Sub-group analysis indicated a stark contrast in vaccination coverage across centers, ranging from 0%-56%.CONCLUSIONHBV-vaccination after HBV screening was very low in this study, which appeared largely attributed to physician-patient motivation towards vaccination. Increased vaccination coverage might be achieved by emphasizing its need at the organizational level.

Rotavirus genotypes as etiological agents of diarrhoea in general populations of two geographic regions of Brazil.

ABSTRACTRotavirus is the main global cause of severe childhood diarrhoea among children. In 2006, Rotarix® (G1P[8]) was introduced into Brazil’s National Immunization Program. The vaccine coverage rate was 84.4% in 2009. Evidences of increasing G2P[4] after 2006 opened up the discussion about the vaccine effectiveness to non-G1 strains. The aim of this study was to identify the circulating rotavirus genotypes in two Brazilian regions during 2009. A total of 223 positive samples by immunochromatography and latex agglutination assay from the Northeast (Bahia/Pernambuco States) and Southeast (São Paulo/Rio de Janeiro States) regions were included in the study. The samples were submitted to genotyping by nested-PCR according to VP7(G) and VP4(P) and 175 samples (78.5%) were able to be characterized. Considering the characterization of VP7, the G-types detected were G1, G2, and G4 in the Northeast, and G2, G3, G5, and G9 in the Southeast. Considering the characterization of VP4, the P-types detected were P[4], P[8], and P[6]/P[9] in the Northeast and the Southeast. The most frequent mixed types found were G2P[4]/G2P[NT](81.4%), G2P[6](5.2%), G1P[6](5.2%) in the Northeast, and G2P[4]/G2P[NT](78.8%), G2P[6](8.2%), G9P[8](4.7%) in the Southeast. Among immunized individuals whose age ranged from 0-4 years, the G2P[4]/G2P[NT] genotype was identified in 91,0% of cases, and among non-immunized individuals of the same age, the G2P[4]/G2P[NT] genotype was identified in 85.7% of the cases. In accordance with the high level of vaccine coverage, the data suggest that the circulation of G2P[4] in these regions had a considerable increase after the introduction of Rotarix®.

Human Zika and West Nile virus neurological infections: What is the difference?

The recent epidemic of West Nile Virus (WNV) infection in the United States was associated with severe neurological disease in immunocompromised hosts, while the emergence of Zika virus infection in the Americas has been notable for an association with increased microcephaly in the fetuses of infected mothers. Rare autopsies of WNV infected humans have shown multiple organ involvement with a clear neurotropism. We have recently had the opportunity to examine the distribution of Zika virus in autopsies of newborns from infected pregnancies. While both viruses infect multiple organs, Zika appears to cause neurological disease in the fetus through two different mechanisms. Infection during the first trimester showed the potential to infect neural progenitor cells causing severe developmental abnormalities, while infection later in gestation was associated with meningeal infection and destructive ischemic lesions of the brain. Both viruses infect kidney tubules but Zika shares a prominent hepatotropism characteristic of other flaviviruses (e.g., Dengue). Limited transplacental Zika infection would be consistent with restriction to primary maternal infections with high viremia. In the absence of a vaccine, restriction of travel by immunosuppressed and pregnant non-immune individuals to endemic regions seems prudent.

Effectiveness of a serological tool to predict malaria transmission intensity in an elimination setting

BackgroundSri Lanka achieved the WHO certificate as a malaria free country in September 2016, thus monitoring of malaria transmission using sensitive and effective tools is an important need. Use of age-specific antibody prevalence as a serological tool to predict transmission intensity is proven to be a cost effective and reliable method under elimination settings. This paper discusses the correlation of four anti-malarial antibodies against vivax and falciparum malaria with the declining transmission intensities in two previously high malaria endemic districts i.e. Kurunegala and Moneragala of Sri Lanka.MethodsSera was collected from 1,186 individuals from the two districts and were subjected to standard ELISA together with control sera from non-immune individuals to obtain Optical Density (OD) values for four anti-malarial antibodies i.e. anti-MSP1 and anti-AMA1 for both Plasmodium vivax and Plasmodium falciparum. The sero-positive samples were determined as mean OD + 3SD of the negative controls. The sero-prevalence was analyzed against the demographic characteristics of the population. A simple reversible catalytic model was fitted into sero-prevalence data to predict the sero-conversion and sero-reversion rates.ResultsOver 60% of the population was sero-positive for one or more antibodies except young children (<10 years). The sero-prevalence was zero in young children and very low in young adults when compared to the older age groups. The model developed for falciparum malaria that assumed the presence of a change in transmission was not significant in the Kurunegala district although significant reduction in transmission was observed when the model was used for P. vivax antibody data in that district. In Moneragala district however, all the serological markers indicated a change in transmission that has occurred approximately 15 years ago.ConclusionsAssessment of MSP1 and AMA1 anti-malarial antibodies of P. vivax and P. falciparum proved to be useful indicators in predicting transmission under elimination settings as prevailed in Sri Lanka. The sero-conversion rates for the two districts studied are shown to be very low or zero indicating the absence of active and/or hidden transmission confirming a “true” state of elimination at least, in the two study districts in Sri Lanka.

Aptamer Technology: Adjunct Therapy for Malaria.

Malaria is a life-threatening parasitic infection occurring in the endemic areas, primarily in children under the age of five, pregnant women, and patients with human immunodeficiency virus and acquired immunodeficiency syndrome (HIV)/(AIDS) as well as non-immune individuals. The cytoadherence of infected erythrocytes (IEs) to the host endothelial surface receptor is a known factor that contributes to the increased prevalence of severe malaria cases due to the accumulation of IEs, mainly in the brain and other vital organs. Therefore, further study is needed to discover a new potential anti-adhesive drug to treat severe malaria thus reducing its mortality rate. In this review, we discuss how the aptamer technology could be applied in the development of a new adjunct therapy for current malaria treatment.

Postexposure prophylaxis with intravenous immunoglobulin G prevents infants from getting measles.

Abstract Most non-immune individuals exposed to the highly contagious measles virus will develop measles. Complications, such as encephalitis and bacterial infections due to measles virus-induced immunomodulation, account for an acute mortality rate of approximately 0.1% (1). It has been calculated that measles-related immunomodulation may last for several years and may contribute to child mortality on a larger scale than acute measles-related mortality (2). Since humans provide the only host for the virus, and an efficient vaccine is available, it is possible to eliminate measles. Vaccination is not recommended for infants younger than six months of age and non-vaccinated infants are best protected by herd immunity and intrauterine acquired antibodies. Herd immunity is achieved by population-wide measles vaccination coverage of at least 95%, which is still rare. Therefore, measles remains one of the leading global causes of death among young children and approximately 82,100 children under the age of five died from measles in 2013 (1). This article is protected by copyright. All rights reserved.

Exchange Transfusion and Predictors of Outcome in Severe Falciparum Malaria

Introduction With an estimated 300-350 million cases and 1-3 million deaths, annually, malaria continues to be a major health concern especially in Sub-Saharan Africa and South-East Asia. 1 In India malaria has staged a comeback after the early 1960s when an all-time low of malaria cases (49,151 in 1963) seemed to suggest the possibility of an impending eradication. During the last few years India has recorded about 2 million confirmed malarial cases and 1,000 deaths annually. These figures reveal just the tip of the iceberg as the WHO estimates about 15 million cases and 20,000 deaths annually. 2 Severe malaria occurs when the effective treatment is delayed, either because of poor access to health care and delay in diagnosis or because the drugs given are ineffective in rapidly clearing the parasite. 3 Non-immune individuals are particularly susceptible to severe falciparum malaria. Multiple organ dysfunction occurs once the disease takes a severe course, causing mortality as high as 50%. There is little pharmaceutical interest in development of new drugs due to low monetary returns on investment 4