Flu virus infection is a common cause of acute respiratory illness, with the major incidence in pediatric age, high morbidity, and mortality. The flu vaccine is recommended for all people aged ≥6 months, unless specific contraindications are present. Younger and older age, pregnancy, chronic diseases like asthma, and immunodeficiency are risk factors for severe complications following flu infection. Thus, these categories represent the target for flu vaccine strategies in most countries. Inactivated influenza vaccine (IIV), recombinant influenza vaccine (RIV) or live-attenuated influenza virus (LAIV) are currently available, with specific precautions and contraindications. We aim to resume the current indications for vaccines in the vulnerable populations to support flu vaccination inclusiveness, in anticipation of a "universal vaccine" strategy.Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also known as COVID-19, is a new strain of coronavirus that has not been previously identified in humans. SARS-CoV-2 is recognized as a highly contagious respiratory virus with severe morbidity and mortality, especially in vulnerable populations. Being a novel disease, everyone is susceptible, there are no vaccine and no treatment. To contain the spread of the disease, health authorities throughout the world have restricted the social interactions of individuals in various degrees. Allergists, like other physicians, are faced with the challenge of providing care for their patients, while protecting themselves and patients from getting infected, with strategies that are in continuous evolution as states work through the different stages of social distance. Allergist provides care for patients with the most common non-communicable disease in the world asthma, allergic rhinitis, food allergy, venom allergy, drug allergy atopic dermatitis, and urticarial syndromes. Some of these diseases are not only considered risk factors for severe reactions but also have symptoms such as cough and sneezing that are in differential diagnosis with COVID-19. As we move forward, allergy symptoms may prevent patients from working, go to school, or access medical services that increasingly are allowing only asymptomatic individuals. In this review, we will outline how to take care safety of different allergic patients during the pandemic.The clinical spectrum of SARS-CoV-2 infection is mixed. It ranges from asymptomatic cases, medium-intensity forms with mild to moderate symptoms, to severe ones with bilateral lung involvement and respiratory distress, which can require transfer to ICUs and intubation. In most cases, the clinical picture is characterized by a persistent fever, cough, dyspnoea, expectoration, myalgias, arthralgias, headache, gastrointestinal symptoms, nasal congestion, and pharyngodynia. The spread of COVID-19 in Europe has highlighted an atypical presentation of disease involving upper airways and, above all, dysfunction of olfactory and gustatory senses. There is ample evidence that COVID-19 is significantly less severe in children than in adults. However, due to difficulties in assessing the disorder in children, especially among very young patients, the olfaction and gustatory dysfunctions remain open issues. This article sheds light on the upper airway involvement in pediatric COVID-19 subjects.Hypersensitivity reactions (HRs) to proton pump inhibitors (PPIs) are mainly described in adults. Anyway, increased use of PPIs in childhood has been observed in recent years. In the literature, only case reports are published on children. Most of the PPI HRs are IgE-mediated. Skin test concentrations and allergy workup protocols used for adults are also applied in children. This study underlies that multicentric pediatric studies focusing on PPI reactions in children are needed.Interleukin (IL)-5 is a potent mediator of the inflammatory cascade in the allergic response. Its predominant role in atopic reactions makes this cytokine an ideal target for blocking the eosinophilic inflammatory hyper-responsiveness to allergens. The management of allergic diseases in childhood-such as severe asthma, atopic dermatitis, and eosinophilic esophagitis-is a challenge. In particular, there are concerns regarding the use of high-dose corticosteroids. Over the last few years, biologics targeting IL-5 or IL-5 receptor-that are mepolizumab, reslizumab, and benralizumab-represent a new, promising, and more personalized therapeutic option.COVID-19 is a complex new viral disease, in which a strict balance between anti-viral immune response and the ensuing organ inflammation has a critical role in determining the clinical course. In adults, compelling evidence exists indicating that an uncontrolled inflammatory response ("cytokine storm") is pivotal in determining disease progression and mortality. Children may rarely present with severe disease. Modulating factors related to the host's genetic factors, age-related susceptibility, and the capability to mount appropriate immune responses might play a role in control virus load at an early stage and regulating the inflammatory reaction.  https://www.selleckchem.com/products/estradiol-benzoate.html  Elucidating these mechanisms seems crucial in developing target therapies according to patient's age, immunologic status, and disease evolution in COVID-19.Common variable immunodeficiency (CVID) is the most prevalent primary immune deficiency, affecting roughly 2-4/100 000 individuals in the general population. The etiology is currently unknown, even if several genetic mutations have been described, and no single clinical feature or single laboratory test can establish the diagnosis, which is based on multiple criteria. CVID is characterized by B- and T-cell dysfunction that predisposes to an increased risk of infections, with the typical involvement of the respiratory and gastrointestinal tracts. Besides this well-established complication, though the coexistence of immunodeficiency and autoimmunity appears paradoxical, two-thirds of CVID patients present concomitant autoimmune disorders. Of note, autoimmunity can often be the only clinical manifestation of CVID at the time of diagnosis. The most common autoimmune disorders associated with CVID are autoimmune cytopenias, that is, immune thrombocytopenic purpura and autoimmune hemolytic anemia, either as separate entities or as concurrently (Evans syndrome).