Intranasally administered immunoglobulin for the prevention of rhinitis in children

In vivo antiviral efficacy of LCTG-002, a pooled, purified human milk secretory IgA product, against SARS-CoV-2 in a murine model of COVID-19

Immunoglobulin A (IgA) is the most abundant antibody (Ab) in human mucosae, with secretory form (sIgA) being dominant and uniquely stable. sIgA is challenging to produce recombinantly but is naturally found in human milk, which could be considered a global resource for this biologic, justifying its development as a mucosal therapeutic. Presently, SARS-CoV-2 was utilized as a model mucosal pathogen, and methods were developed to efficiently extract human milk sIgA from donors who were naïve to SARS-CoV-2 or had recovered from infection that elicited high-titer anti-SARS-CoV-2 Spike sIgA in their milk (pooled to make LCTG-002). Mass spectrometry determined that proteins with a relative abundance of 1% or greater were all associated with sIgA. Western blot demonstrated that all batches consisted predominantly of sIgA. Compared to control IgA, LCTG-002 demonstrated significantly higher Spike binding (mean endpoint of 0.87 versus 5.87). LCTG-002 was capable of blocking the Spike receptor-binding domain - angiotensin-converting enzyme 2 (ACE2) interaction with significantly greater potency compared to control (mean LCTG-002 IC50 154ug/mL versus 50% inhibition not achieved for control), and exhibited significant neutralization activity against Spike-pseudotyped virus infection (mean LCTG-002 IC50 49.8ug/mL versus 114.5ug/mL for control). LCTG-002 was tested for its capacity to reduce viral lung burden in K18+hACE2 transgenic mice inoculated with SARS-CoV-2. LCTG-002 significantly reduced SARS-CoV-2 titers compared to control when administered at 0.25 mg/day or 1 mg/day, with a maximum TCID50 reduction of 4.9 logs. This innovative study demonstrates that LCTG-002 is highly pure and efficacious in vivo, supporting further development of milk-derived, polyclonal sIgA therapeutics.

A new hope? Possibilities of therapeutic IgA antibodies in the treatment of inflammatory lung diseases

Inflammatory lung diseases represent a persistent burden for patients and the global healthcare system. The combination of high morbidity, (partially) high mortality and limited innovations in the last decades, have resulted in a great demand for new therapeutics. Are therapeutic IgA antibodies possibly a new hope in the treatment of inflammatory lung diseases? Current research increasingly unravels the elementary functions of IgA as protector against infections and as modulator of overwhelming inflammation. With a focus on IgA, this review describes the pathological alterations in mucosal immunity and how they contribute to chronic inflammation in the most common inflammatory lung diseases. The current knowledge of IgA functions in the circulation, and particularly in the respiratory mucosa, are summarized. The interplay between neutrophils and IgA seems to be key in control of inflammation. In addition, the hurdles and benefits of therapeutic IgA antibodies, as well as the currently known clinically used IgA preparations are described. The data highlighted here, together with upcoming research strategies aiming at circumventing the current pitfalls in IgA research may pave the way for this promising antibody class in the application of inflammatory lung diseases.

IgY antibodies: The promising potential to overcome antibiotic resistance

Antibiotic resistant bacteria are a growing threat to global health security. Whilst the emergence of antimicrobial resistance (AMR) is a natural phenomenon, it is also driven by antibiotic exposure in health care, agriculture, and the environment. Antibiotic pressure and inappropriate use of antibiotics are important factors which drive resistance. Apart from their use to treat bacterial infections in humans, antibiotics also play an important role in animal husbandry. With limited antibiotic options, alternate strategies are required to overcome AMR. Passive immunization through oral, nasal and topical administration of egg yolk-derived IgY antibodies from immunized chickens were recently shown to be effective for treating bacterial infections in animals and humans. Immunization of chickens with specific antigens offers the possibility of creating specific antibodies targeting a wide range of antibiotic-resistant bacteria. In this review, we describe the growing global problem of antimicrobial resistance and highlight the promising potential of the use of egg yolk IgY antibodies for the treatment of bacterial infections, particularly those listed in the World Health Organization priority list.

Affordable IgY-based antiviral prophylaxis for resource-limited settings to address epidemic and pandemic risks

Background

The COVID-19 pandemic caused by SARS-CoV-2 exposed a global problem, as highly effective vaccines are challenging to produce and distribute, particularly in regions with limited resources and funding. As an alternative, immunoglobulins produced in eggs of immunized hens (IgY) can be a simple and inexpensive source for a topical and temporary prophylaxis. Here, we developed a method to extract and purify IgY antibodies from egg yolks of hens immunized against viral pathogen-derived proteins using low-cost, readily available materials, for use in resource-limited settings.

Methods

Existing protocols for IgY purification and equipment were modified, including extraction from yolks and separation of water-soluble IgY using common household reagents and tools. A replacement for a commercial centrifuge was developed, using a home food processor equipped with a 3D printed adapter to enable IgY precipitation. IgY purification was verified using standard gel electrophoresis and Western blot analyses.

Results

We developed a step-by-step protocol for IgY purification for two settings in low- and middle-income countries (LMIC): a local laboratory, where commercial centrifuges are available, or a more rural setting, where an alternative for expensive centrifuges can be used. Gel electrophoresis and Western blot analyses confirmed that the method produced highly enriched IgY preparation; each commercial egg produced ~ 90 mg of IgY. We also designed a kit for IgY production in these two settings and provided a cost estimate of the kit.

Conclusion

IgY purified from eggs of immunized local hens can offer a fast and affordable prophylaxis, provided that purification can be performed in a resource-limited setting. Here, we created a low-cost method that can be used anywhere where electricity is available using inexpensive, readily available materials in place of costly, specialized laboratory equipment and chemicals. This procedure can readily be used now to make an anti-SARS-CoV-2 prophylaxis in areas where vaccines are unavailable, and can be modified to combat future threats from viral epidemics and pandemics.

Immunoglobulin Y for Potential Diagnostic and Therapeutic Applications in Infectious Diseases

Antiviral, antibacterial, and antiparasitic drugs and vaccines are essential to maintaining the health of humans and animals. Yet, their production can be slow and expensive, and efficacy lost once pathogens mount resistance. Chicken immunoglobulin Y (IgY) is a highly conserved homolog of human immunoglobulin G (IgG) that has shown benefits and a favorable safety profile, primarily in animal models of human infectious diseases. IgY is fast-acting, easy to produce, and low cost. IgY antibodies can readily be generated in large quantities with minimal environmental harm or infrastructure investment by using egg-laying hens. We summarize a variety of IgY uses, focusing on their potential for the detection, prevention, and treatment of human and animal infections.

Avian antibodies (IgY) targeting spike glycoprotein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) inhibit receptor binding and viral replication

BACKGROUND

The global pandemic of Coronavirus infectious disease 2019 (COVID-19), caused by SARS-CoV-2, has plunged the world into both social and economic disarray, with vaccines still emerging and a continued paucity of personal protective equipment; the pandemic has also highlighted the potential for rapid emergence of aggressive respiratory pathogens and the need for preparedness. Avian immunoglobulins (IgY) have been previously shown in animal models to protect against new infection and mitigate established infection when applied intranasally. We carried out a proof-of-concept study to address the feasibility of using such antibodies as mucosally-applied prophylaxis against SARS-CoV-2.

METHODS

Hens were immunized with recombinant S1 spike glycoprotein of the virus, and the resulting IgY was evaluated for binding specificity, inhibition of glycoprotein binding to angiotensin converting enzyme-2 (ACE2) protein (the requisite binding site for the virus), and inhibition of viral replication in Vero cell culture.

RESULTS

Titers of anti-S1 glycoprotein IgY were evident in yolks at 14 days post-immunization, peaking at 21 days, and at peak concentrations of 16.8 mg/ml. IgY showed strong and significant inhibition of S1/ACE2 binding interactions, and significantly inhibited viral replication at a concentration of 16.8 mg/ml. Four weeks' collection from eggs of two hens produced a total of 1.55 grams of IgY.

CONCLUSIONS

In this proof-of-concept study we showed that avian immunoglobulins (IgY) raised against a key virulence factor of the SARS-CoV-2 virus successfully inhibited the critical initial adhesion of viral spike glycoproteins to human ACE2 protein receptors and inhibited viral replication in vitro, in a short period using only two laying hens. We conclude that production of large amounts of IgY inhibiting viral binding and replication of SARS-CoV-2 is feasible, and that incorporation of this or similar material into an intranasal spray and/or other mucosal protecting products may be effective at reducing infection and spread of COVID-19.

Prophylaxis of acute respiratory infections via improving the immune system in late preterm newborns with E. coli strain Nissle 1917: a controlled pilot trial

Background

Acute respiratory infections (ARIs), caused by the high level of immaturity of the immune system, are a major cause of morbidity in preterm newborns. The probiotic Escherichia coli strain Nissle 1917 (EcN) is well known for its immuno-modulatory properties and may therefore enhance the immune competence. Thus, EcN administration may provide a promising possibility to decrease the risk of ARIs in this vulnerable group of children. However, clinical data supporting or refuting this hypothesis are, to our knowledge, not available. Therefore, the aim of the presented pilot trial was to collect first data on the efficacy and safety of EcN treatment to prevent ARIs in late preterm newborns.

Methods

Right after birth, 62 late preterm newborns were included into an open-labeled, controlled 4-week trial with two parallel groups and a follow-up phase until the age of 1 year. All children of the treatment group received an EcN suspension orally for 3 weeks, whereas the control group was only observed. Primary efficacy variable was the number of participants with at least one ARI during the first 28 days of life. Secondary efficacy variables were the number of ARIs and the number and duration of hospitalizations caused by ARIs during the first year of life.

Results

The number of participants with at least one ARI during the first 28 days of life was significantly lower in the group treated with EcN compared to that in the control group. Although only of exploratory nature, analyses of secondary efficacy variables suggest that EcN treatment may also reduce the average number of ARIs, the average number of hospitalizations caused by ARIs, and the mean duration of such hospitalizations. There is also some evidence that early EcN treatment may have long-term benefits on newborns’ health status.

Conclusion

The present pilot trial provides first evidence that EcN is able to reduce the incidence of ARIs in the neonatal period of late preterm newborns. Additionally, EcN is characterized by an excellent individual biocompatibility in the absence of adverse drug reactions. Limitations of the current trial are discussed and recommendations for future confirmatory studies are made.

Trial registration

ClinicalTrials.gov identifier: NCT01540162; retrospectively registered on 16 February 2012

Preserved antiviral adaptive immunity following polyclonal antibody immunotherapy for severe murine influenza infection

Passive immunotherapy may have particular benefits for the treatment of severe influenza infection in at-risk populations, however little is known of the impact of passive immunotherapy on the formation of memory responses to the virus. Ideally, passive immunotherapy should attenuate the severity of infection while still allowing the formation of adaptive responses to confer protection from future exposure. In this study, we sought to determine if administration of influenza-specific ovine polyclonal antibodies could inhibit adaptive immune responses in a murine model of lethal influenza infection. Ovine polyclonal antibodies generated against recombinant PR8 (H1N1) hemagglutinin exhibited potent prophylactic capacity and reduced lethality in an established influenza infection, particularly when administered intranasally. Surviving mice were also protected against reinfection and generated normal antibody and cytotoxic T lymphocyte responses to the virus. The longevity of ovine polyclonal antibodies was explored with a half-life of over two weeks following a single antibody administration. These findings support the development of an ovine passive polyclonal antibody therapy for treatment of severe influenza infection which does not affect the formation of subsequent acquired immunity to the virus.

Effect of Nasal Corticosteroid on Secretory Immunoglobulin A Measured in Rat Nasal Lavage: Experimental Study

OBJECTIVE

In this study, we aimed to experimentally investigate the effects of nasal corticosteroids on the levels of secretory immunoglobulin A (sIgA) in nasal mucosa in rats.

STUDY DESIGN

Prospective, randomized control trial.

SETTING

Research laboratory.

SUBJECT AND METHODS

Twenty-four male Sprague Dawley rats were included in our study. The rats were randomized into 3 groups. In group 1, nasal mometasone furoate was applied to the rats for 30 days. Saline was applied to group 2 for 30 days. Group 3 was the control group and received no treatment throughout the study period. Nasal lavage was conducted on both nasal openings of all rats in the 3 groups at the beginning of the study and on days 15 and 30, and the lavage solution (distilled water) was collected by aspiration.

RESULTS

In group 1, the sIgA value was significantly higher at day 15 than at baseline. No significant difference was found between the sIgA values on day 15 and day 30. In groups 2 and 3, there were no significant differences in sIgA values at baseline, day 15, and day 30. The sIgA value of group 1 on day 15 was significantly higher than the values of groups 2 and 3. The sIgA value of group 1 on day 30 was significantly higher than the values of groups 2 and 3.

CONCLUSION

Topical corticosteroids (mometasone furoate) applied to the nasal mucosa significantly increase nasal sIgA levels.

Immunoglobulin replacement therapy for primary immunodeficiencies

Exogenous antibody therapy to protect patients against infections and toxins is over 100 years old, yet progress continues to be made in the manufacture, administration and application of this type of immunotherapy, known as therapeutic human immunoglobulin. For the majority of patients with primary immunodeficiencies, immunoglobulin replacement is the only life-saving therapy and treatment is life-long, since the vast majority of primary immunodeficiency patients have primary antibody failure. Successful treatment depends on multiple factors: the availability of products, the type of immunodeficiency and any comorbidities of the individual patient. Essential components include long-term follow-up, regular monitoring and a close relationship between the patient and the multidisciplinary clinical immunology team. In this article, we describe the current immunoglobulin products and the types of adverse reactions. We provide evidence for clinical decision-making regarding dosing, route of administration and location of therapy, highlighting current ‘best practice’ recommendations.

Multi-faceted functions of secretory IgA at mucosal surfaces

Secretory IgA (SIgA) plays an important role in the protection and homeostatic regulation of intestinal, respiratory, and urogenital mucosal epithelia separating the outside environment from the inside of the body. This primary function of SIgA is referred to as immune exclusion, a process that limits the access of numerous microorganisms and mucosal antigens to these thin and vulnerable mucosal barriers. SIgA has been shown to be involved in avoiding opportunistic pathogens to enter and disseminate in the systemic compartment, as well as tightly controlling the necessary symbiotic relationship existing between commensals and the host. Clearance by peristalsis appears thus as one of the numerous mechanisms whereby SIgA fulfills its function at mucosal surfaces. Sampling of antigen-SIgA complexes by microfold (M) cells, intimate contact occurring with Peyer’s patch dendritic cells (DC), down-regulation of inflammatory processes, modulation of epithelial, and DC responsiveness are some of the recently identified processes to which the contribution of SIgA has been underscored. This review aims at presenting, with emphasis at the biochemical level, how the molecular complexity of SIgA can serve these multiple and non-redundant modes of action.

Secretory IgA's complex roles in immunity and mucosal homeostasis in the gut

Secretory IgA (SIgA) serves as the first line of defense in protecting the intestinal epithelium from enteric toxins and pathogenic microorganisms. Through a process known as immune exclusion, SIgA promotes the clearance of antigens and pathogenic microorganisms from the intestinal lumen by blocking their access to epithelial receptors, entrapping them in mucus, and facilitating their removal by peristaltic and mucociliary activities. In addition, SIgA functions in mucosal immunity and intestinal homeostasis through mechanisms that have only recently been revealed. In just the past several years, SIgA has been identified as having the capacity to directly quench bacterial virulence factors, influence composition of the intestinal microbiota by Fab-dependent and Fab-independent mechanisms, promote retro-transport of antigens across the intestinal epithelium to dendritic cell subsets in gut-associated lymphoid tissue, and, finally, to downregulate proinflammatory responses normally associated with the uptake of highly pathogenic bacteria and potentially allergenic antigens. This review summarizes the intrinsic biological activities now associated with SIgA and their relationships with immunity and intestinal homeostasis.

Immunostimulants for preventing respiratory tract infection in children

BACKGROUND

Acute respiratory tract infections (ARTIs) are a major cause of childhood morbidity and mortality. Immunostimulants (IS) may reduce the incidence of ARTIs.

OBJECTIVES

To determine the efficacy and safety of IS in preventing ARTIs in children.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2005); MEDLINE (January 1966 to January 2006); and EMBASE (January 1990 to January 2006); PASCAL (up to January 2006); SciSearch (up to January 2006); and IPA (up to January 2006) for reports of trials. Investigators in the field were also contacted. Ongoing studies were searched in the trial registration web site, metaRegister of Controlled Trials.

SELECTION CRITERIA

All comparative trials which enrolled patients less than 18 years of age were included. The intervention of interest was the use of an IS medication administered by any method for preventing ARTIs. Clinical trials using random or quasi-random allocation and comparing IS medication or medications to placebo were included.

DATA COLLECTION AND ANALYSIS

The outcome on ARTIs was analyzed both as the mean number of ARTIs by group and as a percent change in the rate of ARTIs. Meta-analysis was undertaken using a random-effects model and results were presented as weighted mean differences (WMD) with 95% confidence intervals (CI). The trials search, quality assessment and data extraction were undertaken independently by two authors. A funnel plot suggested there may be publication bias in the trials identified.

MAIN RESULTS

Thirty-four placebo controlled trials (3877 participants) provided data in a form suitable for inclusion in the meta-analysis. When compared with placebo, the use of IS was shown to reduce ARTIs measured as the total numbers of ARTIs (WMD -1.27; 95% CI -1.58 to -0.97) and the difference in ARTIs rates (WMD -39.68%; 95% CI -47.27% to -32.09%). The trial quality was generally poor and a high level of statistical heterogeneity was evident. The subgroup analysis of bacterial IS studies produced similar results, with lower heterogeneity. No difference in adverse events was evident between the placebo and IS groups

AUTHORS' CONCLUSIONS

This review showed that IS reduces the incidence of ARTIs in children, by 40% on average. However, due to significant heterogeneity and the poor quality of the trials this positive result should be interpreted with caution. The safety profile of IS appears to be good. Further high-quality trials are needed and we encourage national health authorities to conduct large, multicenter, double-blind, placebo-controlled trials on the role of IS in the prevention of ARTIs.

Rhinopharyngites de l’enfant

La rhinopharyngite désigne une inflammation modérée des voies aériennes supérieures d’origine infectieuse. Les signes habituels en sont l’obstruction nasale, la rhinorrhée, l’éternuement, la douleur pharyngée et la toux. Le terme de rhinopharyngite est spécifiquement français. Les auteurs anglo-saxons parlent de rhume (common cold) ou de upper respiratory tract infection (URI) pour décrire une inflammation aiguë des voies aériennes supérieures, et d’adénoïdite chronique (chronic adenoiditis) pour désigner une infection chronique des végétations adénoïdes responsable de rhinorrhées fébriles itératives ou d’obstruction des voies aériennes supérieures. Les rhinopharyngites aiguës non compliquées sont d’origine virale. Leur évolution spontanée est habituellement rapide et non compliquée. Elles ne nécessitent donc ni prélèvement bactériologique ni antibiothérapie systématique. En première intention, elles relèvent exclusivement d’un traitement antalgique et antipyrétique associé à des lavages des fosses nasales au sérum salé iso- ou hypertonique. Les complications des rhinopharyngites sont infectieuses, essentiellement représentées par les otites et les sinusites, et respiratoires obstructives. Le caractère fréquemment itératif des rhinopharyngites à partir de l’âge de 6 mois reflète un processus physiologique de maturation du système immunitaire. En présence de rhinopharyngites fréquentes et invalidantes, les principaux facteurs de risque devant être recherchés et si possible éradiqués sont le tabagisme passif et la fréquentation d’une collectivité d’enfants. L’adénoïdectomie n’est pas indiquée en l’absence de complications. Le développement d’antiviraux efficaces dans la prévention et dans le traitement des rhinopharyngites fait l’objet d’intenses recherches cliniques et expérimentales.

Rinofaringitis infantiles

La rinofaringitis designa una inflamación moderada de las vías respiratorias superiores de origen infeccioso. Sus signos habituales son obstrucción nasal, rinorrea, estornudos, dolor faríngeo y tos. Los autores anglosajones hablan de catarro (common cold) o de infección de vías respiratorias altas para describir una inflamación de las vías respiratorias superiores, y de adenoiditis crónica (chronic adenoiditis) para designar una infección crónica de las vegetaciones adenoides que produce rinorrea febril recidivante u obstrucción de las vías respiratorias altas. Las rinofaringitis agudas no complicadas son de origen vírico. Habitualmente su evolución espontánea es rápida y sin complicaciones. Por tanto, no hay que obtener muestras bacteriológicas ni hacer un tratamiento antibiótico sistemático. Como tratamiento de primera línea, sólo precisan analgésicos y antipiréticos asociados a lavados de las fosas nasales con suero salino isotónico o hipertónico. Las complicaciones de las rinofaringitis son infecciosas –representadas esencialmente por las otitis y las sinusitis– y respiratorias obstructivas. El carácter a menudo repetitivo de las rinofaringitis a partir de los 6 meses de edad refleja un proceso fisiológico de maduración del sistema inmunitario. Cuando existen rinofaringitis frecuentes e invalidantes, los principales factores de riesgo que se deben buscar, y de ser posible erradicar, son el tabaquismo pasivo y los contactos con una población infantil. La adenoidectomía ya no está indicada si no existen complicaciones. Se están realizando investigaciones clínicas y experimentales sobre el desarrollo de fármacos antivíricos eficaces para la prevención y el tratamiento de las rinofaringitis.

Importance of respiratory viruses in acute otitis media

Acute otitis media is usually considered a simple bacterial infection that is treated with antibiotics. However, ample evidence derived from studies ranging from animal experiments to extensive clinical trials supports a crucial role for respiratory viruses in the etiology and pathogenesis of acute otitis media. Viral infection of the upper respiratory mucosa initiates the whole cascade of events that finally leads to the development of acute otitis media as a complication. The pathogenesis of acute otitis media involves a complex interplay between viruses, bacteria, and the host's inflammatory response. In a substantial number of children, viruses can be found in the middle-ear fluid either alone or together with bacteria, and recent studies indicate that at least some viruses actively invade the middle ear. Viruses appear to enhance the inflammatory process in the middle ear, and they may significantly impair the resolution of otitis media. Prevention of the predisposing viral infection by vaccination against the major viruses would probably be the most effective way to prevent acute otitis media. Alternatively, early treatment of the viral infection with specific antiviral agents would also be effective in reducing the occurrence of acute otitis media.

The common cold

Despite great advances in medicine, the common cold continues to be a great burden on society in terms of human suffering and economic losses. Of the several viruses that cause the disease, the role of rhinoviruses is most prominent. About a quarter of all colds are still without proven cause, and the recent discovery of human metapneumovirus suggests that other viruses could remain undiscovered. Research into the inflammatory mechanisms of the common cold has elucidated the complexity of the virus-host relation. Increasing evidence is also available for the central role of viruses in predisposing to complications. New antivirals for the treatment of colds are being developed, but optimum use of these agents would require rapid detection of the specific virus causing the infection. Although vaccines against many respiratory viruses could also become available, the ultimate prevention of the common cold seems to remain a distant aim.

Safety and efficacy of two courses of OM-85 BV in the prevention of respiratory tract infections in children during 12 months

BACKGROUND

Acute respiratory tract infections (ARTIs) are among the main causes of morbidity and mortality in children. The bacterial extract OM-85 BV (bronchovaxom) has shown protective effect for ARTIs on children. We report a double-blind, placebo-controlled, parallel, prospective clinical trial to assess the safety and efficacy of two courses of OM-85 BV in the prevention of ARTIs in susceptible children during 12 months.

METHODS

Fifty-four susceptible children from 1 to 12 years of age living in the metropolitan area of Chihuahua City were selected. They were randomized to receive either OM-85 BV or placebo (one capsule a day for 10 days a month for 3 consecutive months) at the beginning of the trial and 6 months later with the same schedule. Patients were followed up for 12 months, including the administration period. The trial began in July 1997 and ended in April 1999.

RESULTS

The number (mean +/- SD) of ARTIs was 5.04 +/- 1.99 (median, 5.0) in the OM-85 BV group vs 8.0 +/- 2.55 (median, 8.0) in the placebo group, with a mean difference of - 2.96 (95% confidence interval [CI], - 4.22 to - 1.7). The number of antibiotic courses was 2.46 +/- 2.08 (median, 1.5) in the treatment group vs 4.46 +/- 2.08 (median, 4.0) in the control group, a difference of - 2.0 (95% CI, - 3.14 to - 0.86). The total duration of ARTIs was 35.23 +/- 17.64 days (median, 30.5 days) in the OM-85 BV group vs 60.75 +/- 25.44 days (median, 55.0 days) in the placebo group, ie, a difference of - 25.52 days (95% CI, - 37.56 to - 13.47 days), p < 0.001 by Student's t test and Mann-Whitney U test for all the items. Four patients in the OM-85 BV group had five adverse events. Only one episode of skin rash was related to the medication intake. Six patients in the control group had six adverse events.

CONCLUSIONS

OM-85 BV had a preventive effect on ARTI in the susceptible children for 12 months with an important reduction on the antibiotic requirements and the number of days of suffering ARTIs.

Intranasal antibody prophylaxis for protection against viral disease

For more than a century, antibody has been used for passive parenteral immunization against viral and bacterial pathogens. This approach has been successful for prevention of viral respiratory infection and has led to testing of intranasal or aerosol delivery of antibody to passively immunize the respiratory tract mucosal surface. Mucosal delivery may be advantageous because it allows the antibody to neutralize the virus particles before they initiate infection and because it concentrates the antibody where viral replication takes place. Animal studies have shown the feasibility of passive intranasal immunization against a number of respiratory tract viruses. Development of nasal antibody treatments for humans is under way, and early clinical studies have confirmed that this approach is safe and can be used to prevent respiratory tract disease. Polyclonal human immunoglobulin from pooled plasma preparations can be used to provide broad protection against a number of different pathogens, while monoclonal antibodies or their fragments can be used to target specific viruses.