Multisystem Inflammatory Syndrome in Children Related to SARS-CoV-2

Although data on the incidence and severity of new coronavirus disease 2019 (COVID-19) due to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection showed more significant disease among adults and the elderly, a clinical manifestation characterized by a multisystem inflammatory syndrome was described in children (MIS-C). It was initially thought to be specific to children, but recent reports have shown that it can also occur in adults. MIS-C is characterized by a number of multisystemic manifestations resembling other known previously described illnesses, mainly Kawasaki disease, especially in cases with shock, toxic shock syndrome, and macrophage activation syndrome. Available literature shows that our knowledge of MIS-C is largely incomplete. Its development in strict relation with SARS-CoV-2 infection seems documented and, in most cases, can be considered a post-infectious manifestation secondary to an abnormal immune response for some aspects, similar to that seen in adults several days after SARS-CoV-2 infection. However, in a minority of cases, a clinical picture with symptoms fulfilling criteria for MIS-C diagnosis develops during the acute phase of SARS-CoV-2 infection. It is highly likely that the criteria currently used to diagnose MIS-C are too broad, meaning that children with different diseases are included. As clarity on the pathogenesis of MIS-C is lacking, different therapeutic approaches have been used, but no specific therapy is currently available. Further studies are urgently needed to improve our definition of MIS-C, to define the real impact on child health, and to elucidate the best clinical and therapeutic approach and true prognosis

Norovirus Vaccine: Priorities for Future Research and Development

Soon after its identification, norovirus (NoV) has been indicated as one of the most common causes of outbreaks of acute gastroenteritis (AGE) and sporadic acute diarrhea episodes in subjects of any age. In 2016 the World Health Organization stated that the development of a NoV vaccine should be considered an absolute priority. Unfortunately, the development of an effective NoV vaccine has proven extremely difficult, and only in recent years, some preparations have been tested in humans in advanced clinical trials. In this paper, reasons that justify efforts to develop a NoV vaccine, difficulties encountered during NoV vaccine development, and NoV vaccine candidates will be discussed. In recent years, identification of some NoV antigens that alone or in combination with other viral antigens can induce a potentially protective immune response has led to the development of a large series of preparations that seem capable of coping with the problems related to NoV infection. Epidemiological and immunological studies have shown that multivalent vaccines, including both GI and GII NoV, are the only solution to induce sufficiently broad protection. However, even if the road to formulation of an effective and safe NoV vaccine seems to be definitively traced, many problems still need to be solved before the total burden of NoV infections can be adequately controlled. Whether currently available vaccines are able to protect against all the heterologous NoV strains and the variants of the most common serotypes that frequently emerge and cause outbreaks must be defined. Moreover, as performed clinical trials have mainly enrolled adults, it is mandatory to know whether vaccines are effective in all age groups, including younger children. Finally, we must know the immune response of immunocompromised patients and the duration of protection induced by NoV vaccines. Only when all these problems have been solved will it be possible to establish an effective immunization schedule against NoV infection and calculate whether systematic vaccination can be cost effective

Unsolved problems and new medical approaches to otitis media

Introduction: Otitis media (OM) is a spectrum of infectious and inflammatory diseases that involve the middle ear. It includes acute otitis media (AOM), otitis media with effusion (OME) and chronic suppurative otitis media (CSOM). Areas covered: This manuscript discusses some of the emerging and unsolved problems regarding OM, and some of the newly developed prophylactic and therapeutic medical measures. Expert opinion: In recent years, considerable progress in the knowledge of OM physiopathology has been made. However, although extremely common, diseases included under OM have not been adequately studied, and many areas of development, evolution and possible treatments of these pathologies are not defined. It is necessary that these deficiencies be quickly overcome if we want to reduce the total burden of a group of diseases that still have extremely high medical, social and economic relevance

Do Vaccines Have a Role as a Cause of Autoimmune Neurological Syndromes?

Vaccines are the most important preventive measure against infectious diseases presently available. Although they have led to the eradication or the elimination of some infectious diseases, concerns about safety are among the main reasons for vaccine hesitancy. In some cases, the biological plausibility of a given damage in association with the temporal association between vaccine administration and disease development makes it difficult to define causality and can justify hesitancy. Only well-conducted epidemiological studies with adequate evaluation of results can clarify whether a true association between vaccines and adverse event development truly exists. Autoimmune neurological syndromes that follow vaccine use are among these. In this narrative review, the potential association between vaccines and the development of these syndromes are discussed. Literature analysis showed that most of the associations between vaccines and nervous system autoimmune syndromes that have been reported as severe adverse events following immunization are no longer evidenced when well-conducted epidemiological studies are carried out. Although the rarity of autoimmune diseases makes it difficult to strictly exclude that, albeit exceptionally, some vaccines may induce an autoimmune neurological disease, no definitive demonstration of a potential role of vaccines in causing autoimmune neurological syndromes is presently available. Consequently, the fear of neurological autoimmune disease cannot limit the use of the most important preventive measure presently available against infectious diseases

Pneumococcal disease prevention: Arewe on the right track?

The history of Streptococcus pneumoniae diseases dramatically changed with the introduction into the immunization schedule of infants and children of the first pneumococcal conjugate vaccine, the one containing 7 (PCV7) of the most common pneumococcal serotypes (STs) causing invasive pneumococcal diseases (IPDs). Where PCV7 was largely used, incidence of both IPDs and non-invasive pneumococcal diseases (nIPDs) in vaccinated children and in unvaccinated subjects of any age, mainly the elderly, significantly decreased. Unfortunately, the impact of PCV7 administration was slightly lower than expected, as the reduction in infections due to vaccine serotypes (STs) was accompanied by a significant increase in the number of IPDs and nIPDs due to STs not included in the vaccine. To overcome this problem, two PCVs containing 10 (PCV10) and 13 (PCV13) STs, chosen among those emerging, were developed and licensed. However, ST replacement occurred again. Moreover, the new PCVs showed little effectiveness in the prevention of infection due to nonencapsulated STs and to ST3. Next-generation S. pneumoniae vaccines able to prevent pneumococcal infections regardless of infecting ST are urgently needed. For the moment, the use of available PCVs remains fundamental because their benefits far outweigh any concerns for emerging STs

Why it is important to develop an effective and safe pediatric COVID-19 vaccine

The need to cope with the medical, social, and economic storm due to the new coronavirus 2019 (COVID-19) pandemic as quickly as possible has led to the very rapid development of a huge number of vaccines. All these vaccines have been mainly developed in healthy adults and, in some cases, in the elderly. Children were marginally involved as, according to the clinical trial registry Clinical Trials.gov, only very few studies have included children among subjects to enroll, although just a few weeks after the pandemic declaration, the US Food and Drug Administration had highlighted the importance of vaccine evaluation in pediatrics. Availability of an effective and safe pediatric COVID-19 vaccine appears mandatory for several clinical and epidemiological reasons. However, as the development of an effective and safe pediatric vaccine seems far from easy, strong cooperation among governments, researchers, and pharmaceutical companies is highly desirable

Is the immunization of pregnant women against covid-19 justified?

Maternal immunization against some infectious diseases can offer significant advantages for women, preventing maternal morbidity and mortality, or for offspring, preventing fetal disease and conferring passive immunity to neonates. Recently, clinical trials specifically to evaluate the immunogenicity, safety, and tolerability of some of the available coronavirus disease 2019 (COVID-19) vaccines in pregnant and lactating women have been planned, initiated and, in some cases, completed. This paper discusses whether the immunization of pregnant women against COVID-19 is justified and presents knowledge about the immunogenicity and safety of mRNA COVID-19 vaccines for these subjects. The results of recent studies indicate that pregnant women are at increased risk of developing severe disease compared with nonpregnant women of the same age. Studies carried out with mRNA vaccines indicate that the immunogenicity, safety and tolerability of these preventive measures in pregnant women are not different from those in nonpregnant women of the same age. Moreover, antibodies are efficiently transferred through the placenta and can be detected in breastmilk, suggesting a potential prevention of infection in the child. All these findings authorize the use of mRNA vaccines in pregnant women to protect both the mother and the child. However, further studies with larger sample size and with follow-up of the pregnant women vaccinated during different periods of pregnancy and their children are needed to better characterize the immune response of pregnant women, to define when these vaccines should be administered to obtain the best protection, and to measure vaccine efficacy against virus variants in both mothers and infants. COVID-19 vaccines based on different technological platforms cannot presently be used, and their role in pregnant women should be clarified