Respiratory Syncytial Virus (RSV) Diseases

The respiratory syncytial virus (RSV) is an RNA virus that causes annual ARI outbreaks during winter with mild URTI in the general population, but with severe LRTI particularly among young children (bronchiolitis), patients with underlying diseases and people >65 years of age. RSV does not induce a long-lasting protective immunity and repeated infections throughout life are the norm. Basically, all children have been infected by 2 years of age and of those hospitalized, >50% are <3 months and 75% are <6 months of age. The overall CFR is 1/500. For adults ≥65 years, RSV hospitalization rates are 90–250/105. There is no specific therapy, general preventive measures include general hygiene and isolation/separation of patients. A monoclonal anti-F-protein antibody is available for passive immunization of selected high-risk children. It requires monthly injections, comes at a high cost and has limited efficacy (50% against RSV hospitalization). Active immunization failed in the past, probably as the post-fusion conformation of the F-protein was used. Long-acting monoclonal antibodies (for infants) as well as stabilized pre-fusion F-protein vaccines (for immunization of pregnant women, children, older adults) produced on various platforms are in late stages of clinical development.

Omicron variant escapes therapeutic mAbs contrary to eight prior main VOC

Monocolonal antibodies (mAbs) are currently used for active immunization of COVID-19 in immunocompromised patients. We herein show that in spite there are variations in susceptibility to available mAbs that are authorized for clinical use in France tested on the original B.1.1 virus and 9 variants of concern or of interest, the cocktail casirivimab/imdevimab (REGN-CoV-2) showed a major synergistic effect. However, none of the four mAbs either alone or in combination neutralized the new Omicron variant. Our data strongly warrant a reinforcement of protective measures against infection for immunocompromised patients.

Therapeutic Efficacy of Entecavir and Tenofovir among the Affectees from War against Terror in the Tribal Areas of Pakistan

BackgroundHepatitis B infection is a worldwide health concern infecting more than 400 million people worldwide. Besides the active immunization program of WHO, the role of antivirals for treating the chronic infection is inevitable. The tribal belt of Pakistan is the most affected part in war against terror. In addition to lack of basic facilities and resources, this part of country has also been neglected for various health related studies. In this study we report the efficacy of the commonly used antivirals; Entecavir (ETV) and Tenofovir Disoproxil Fumarate (TDF).MethodsA total of 2875 HBV infected patients (Male = 1500 and Female = 1375) of different age groups who were receiving either ETV as monotherapy or ETV plus TDF were followed up for 6 and 12 months. Viral DNA was extracted from serum followed by amplification and detection with MyGo Real-Time thermocycler and Gene Proof PCR kit. Response towards antivirals was analyzed statistically with Pearson’s Chi Square test. ResultsComparable response (p=0.171) was observed among the HBV patients towards both six (27%) and twelve month antiviral therapy (36%). Duration of antiviral therapy improved the rate of response in male and patients of old age (p=0.001 & <0.001 respectively). However, female were found relatively more responsive than males towards both six and twelve antiviral therapy (p=0.001 & 0.003 respectively). Furthermore, ETV plus TDF combination proved little more effective for twelve months (p=0.035). Patients of Khyber (p=0.198) and Kurrum (p=0.440) regions are equally responsive towards 6 and 12 month treatment. Compared to ETV monotherapy, ETV plus TDF improved response among the male, patients above 40 years and patients from different tribal region (Bajaur, Kurrum, Malakand and Mohmand). ConclusionOur findings demonstrate that the ETV monotherapy and ETV plus TDF combination therapy are not effective for the HBV infection because both do not achieve SVR rate even in 50% of patients following six and twelve-month follow-up. Therefore, there is a need of much more effective antiviral drugs to treat HBV infection in the study area.

Immune Responses to SARS-CoV-2 Infection and Vaccination in Dialysis Patients and Kidney Transplant Recipients

Dialysis patients and kidney transplant (KTX) recipients suffer from an impaired immune system and show a decreased response to the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) vaccination. We performed a retrospective analysis of 1505 serological SARS-CoV-2 measurements obtained from 887 dialysis patients and 86 KTX recipients. The results were separated by patient subgroups (dialysis/KTX) as well as SARS-CoV-2 status. The latter criterion included SARS-CoV-2-naïve patients with or without COVID-19 vaccination and convalescent patients receiving a booster shot. Serologies of 27 vaccinated healthy individuals served as the reference group. Vaccine-induced cellular immune response was quantified by an interferon-γ release assay in 32 KTX recipients. We determined seroconversion rates of 92.6%, 93.4%, and 71.4% in dialysis patients vaccinated with either BNT162b2, mRNA-1273, or AZD1222, respectively. Vaccination-induced anti-SARS-CoV-2 antibody titers were lower in dialysis patients compared to healthy individuals, and vaccination with mRNA-1273 induced higher titers than BNT162b2. The initial seroconversion rate was 39.5% in KTX recipients vaccinated with BNT162b2. A linear regression model identified medication with mycophenolate-mofetil/mycophenolic acid as an independent risk factor for missing seroconversion. Within a cohort of 32 KTX recipients, cellular and humoral immune reactivity to SARS-CoV-2 was detectable in three patients only. Conclusively, vaccine-induced seroconversion rates were similar in dialysis patients compared to healthy individuals but were strongly impaired in KTX recipients. Anti-SARS-CoV-2 IgG titers elicited by double active immunization were significantly lower in both cohorts compared to healthy individuals, and immune responses to vaccination vanished quickly.

Immunization against severe acute respiratory syndrome Coronavirus 2: an overview

In the past years, numerous new fatal infections have emerged, including Ebola, Nipah, and Zika viruses, as well as coronaviruses. Recently, infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have emerged in China, and were then transmitted all over the world, causing the coronavirus disease-19 (COVID-19) pandemic, which is transmitted at a higher rate than other diseases caused by coronaviruses. At the time of writing this review, COVID-19 is not contained in most countries in spite of quarantine, physical distancing, and enhanced hygiene measures. In this review, I address different methods for passive and active immunization against this virus, which is known to cause fatal respiratory disease, including natural passive immunization by breast milk, natural active immunization by herd immunization, artificial passive immunization by convalescent plasma or monoclonal antibodies, and artificial active immunization by vaccination. I hope this review will help design a prophylactic approach against outbreaks and pandemics of related coronaviruses in the future. Keywords: Breastfeeding; COVID-19; herd immunity; monoclonal antibodies; SARS-CoV; vaccine.

Effectiveness and Safety of an Intravenous Immune Globulin (IVIG) Preparation in Post-exposure Prophylaxis (PEP) Against Measles in Infants

Background: Administration of measles virus (MV)-specific IgG as post-exposure prophylaxis (PEP) is known to effectively prevent measles. Since the introduction of active immunization against measles, the levels of MV-specific IgG antibodies in the population have dropped. Therefore, the concentration of MV-specific antibodies in immunoglobulin products derived from human plasma donors has declined as the proportion of vaccinated donors has increased. Literature on the effectiveness of PEP with current available immunoglobulins is limited. Here we examine the effectiveness of 400 mg/kg intravenous immunoglobulin (IVIG) (IgVena®, Kendrion) as PEP in infants during a measles outbreak in Austria, 2019.Methods: After exposure to a highly contagious measles patient, identified infants were evaluated for eligibility for IVIG PEP. Infants were tested for measles maternal antibodies, if the result was expected to be available within 72 h after exposure. IVIG was administered to eligible infants with negative maternal IgG antibody levels (n = 11), infants with protective levels but result beyond 72 h (n = 2) and infants not tested for maternal IgG antibodies (n = 52). Telephone enquiries were made asking for measles infection. Effectiveness was calculated using exact logistic regression. Samples of four out of seven used IVIG batches were tested for MV-neutralizing antibody capacity.Results: In 63 (96.9%) of 65 infants PEP with IVIG was administered. The parents of two infants declined IVIG PEP. None of the infants with IVIG PEP got measles or symptoms suggestive for measles, but both infants who did not receive PEP were infected. Effectiveness of IVIG PEP was calculated to be 99.3% (CI 95%: 88.7–100%). No serious adverse event of IVIG treatment was observed. The investigation on MV-neutralizing antibody capacity showed a geometric mean titer ranging from 10.0 to 12.7 IU/ml, resulting in a 1.57–2.26-fold higher concentration than postulated as minimum level for immunity.Conclusions: Our findings suggest that the used IVIG preparation provided an at least non-inferior protection rate compared to IVIG preparations derived from donors before the global introduction of standard active immunization against measles.

Perspectives on Assembling Coronavirus Spikes on Fiber Optics to Reveal Broadly Recognizing Antibodies and Generate a Universal Coronavirus Detector

In time of COVID-19 biological detection technologies are of crucial relevance. We propose here the use of state of the art optical fiber biosensors to address two aspects of the fight against SARS-CoV-2 and other pandemic human coronaviruses (HCoVs). Fiber optic biosensors functionalized with HCoV spikes could be used to discover broadly neutralizing antibodies (bnAbs) effective against known HCoVs (SARS-CoV, MERS-CoV and SARS-CoV-2) and likely future ones. In turn, identified bnAbs, once immobilized onto fiber optic biosensors, should be capable to detect HCoVs as diagnostic and environmental sensing devices. The therapeutic and preventative value of bnAbs is immense as they can be used for passive immunization and for the educated development of a universal vaccine (active immunization). Hence, HCoV bnAbs represent an extremely important resource for future preparedness against coronavirus-borne pandemics. Furthermore, the assembly of bnAb-based biosensors constitutes an innovative approach to counteract public health threats, as it bears diagnostic competence additional to environmental detection of a range of pandemic strains. This concept can be extended to different pandemic viruses, as well as bio-warfare threats that entail existing, emerging and extinct viruses (e.g., the smallpox-causing Variola virus). We report here the forefront fiber optic biosensor technology that could be implemented to achieve these aims.

Active immunization by COVID-19 mRNA vaccine results in rapid antibody response and virus reduction in breakthrough infection by Delta (B.1.617.2)

Vaccination is expected to suppress COVID-19 infection. However, breakthrough infections have increased following vaccination because of the spread of variants of concern, notably Delta (B.1.617.2 lineage). Virological and serological data pertaining to post-vaccination infections are limited. Here, we conducted genome analysis determined the viral lineages that infected patients following vaccination. Changes in viral load, antibody levels, and viral antigen levels following infection were analyzed. At the time of infection, Delta-infected patients had a 6.2-fold and 12.3-fold higher viral load compared with Alpha and other lineages, respectively. Viral lineages (Delta:Alpha:Other) of infection were 0:12:0 in the fully vaccinated group, 1:11:0 in the partially vaccinated group, 9:16:0 in the shortly after vaccination group, and 254:229:165 in the unvaccinated group. Breakthrough infections occurred regardless of retention of high antibody titers following vaccination. At the time of diagnosis, Delta-infected patients showed high viral load with or without vaccination. However, no fully vaccinated patients developed severe disease, and the rapid increase in anti-spike antibodies occurred approximately 1 week after onset of symptoms. Concomitantly, a decrease in viral antigen levels was observed in fully vaccinated patients, shortening the time to negative result by approximately 2 days compared with unvaccinated patients. Collectively, even if breakthrough infection occurs, the rapid antibody response in fully vaccinated individuals contributes to prevention of severe disease, possibly because of suppression of viral replication.

Live Birth Rates after Active Immunization with Partner Lymphocytes

Although many potential causes have been established for recurrent implantation failure (RIF) and recurrent miscarriage (RM), about 50% of these remain idiopathic. Scientific research is focused on immunological risk factors. In the present study, we aim to evaluate live birth rates after immunization with paternal lymphocytes (lymphocyte immunotherapy (LIT)). This retrospective study consisted of 148 couples with a history of RM and/or RIF. The women underwent immunization with lymphocytes of their respective partners from November 2017 to August 2019. Fifty-five patients (43%) had live births. Stratified by indication (RM, RIF, combined), live birth rates in the RM and the combined group were significantly higher than that in the RIF group (53%, 59% and 33%, respectively, p = 0.02). The difference was especially noticeable during the first 90 days after immunization (conception rate leading to live births: 31%, 23% and 8% for RM, the combined group and RIF, respectively; p = 0.005), while there was no difference between groups during the later follow-up. LIT was associated with high live birth rates, especially in women with recurrent miscarriage. In view of the limited data from randomized studies, LIT cannot be recommended as routine therapy. However, it may be considered in individual cases.