Clinical and socioeconomic impact of different types and subtypes of seasonal influenza viruses in children during influenza seasons 2007/2008 and 2008/2009

<p>Abstract</p> <p>Background</p> <p>There are few and debated data regarding possible differences in the clinical presentations of influenza A/H1N1, A/H3N2 and B viruses in children. This study evaluates the clinical presentation and socio-economic impact of laboratory-confirmed influenza A/H1N1, A/H3N2 or B infection in children attending an Emergency Room because of influenza-like illness.</p> <p>Methods</p> <p>Among the 4,726 children involved, 662 had influenza A (143 A/H1N1 and 519 A/H3N2) and 239 influenza B infection detected by means of real-time polymerase chain reaction. Upon enrolment, systematic recordings were made of the patients' demographic characteristics and medical history using standardised written questionnaires. The medical history of the children was re-evaluated 5-7 days after enrolment and until the resolution of their illness by means of interviews and a clinical examination by trained investigators using standardised questionnaires. During this evaluation, information was also obtained regarding illnesses and related morbidity among households.</p> <p>Results</p> <p>Children infected with influenza A/H1N1 were significantly younger (mean age, 2.3 yrs) than children infected with influenza A/H3N2 (mean age, 4.7 yrs; p < 0.05)) or with influenza B (mean age, 5.2 yrs; p < 0.05). Adjusted for age and sex, children with influenza A/H3N2 in comparison with those infected by either A/H1N1 or with B influenza virus were more frequently affected by fever (p < 0.05) and lower respiratory tract involvement (p < 0.05), showed a worse clinical outcome (p < 0.05), required greater drug use (p < 0.05), and suffered a worse socio-economic impact (p < 0.05). Adjusted for age and sex, children with influenza B in comparison with those infected by A/H1N1 influenza virus had significantly higher hospitalization rates (p < 0.05), the households with a disease similar to that of the infected child (p < 0.05) and the need for additional household medical visits (p < 0.05).</p> <p>Conclusions</p> <p>Disease due to influenza A/H3N2 viral subtype is significantly more severe than that due to influenza A/H1N1 subtype and influenza B virus, which indicates that the characteristics of the different viral types and subtypes should be adequately considered by health authorities when planning preventive and therapeutic measures.</p

Vaccinations in children with cancer

Children with cancer may be immunocompromised as a result of their primary underlying disease and/or the use of prolonged and intensive chemotherapy administered with or without irradiation. The damage to the immune system varies with the age of the patient, the type of cancer, and the intensity of the chemotherapy used to treat it. This review analyses the data regarding the immunogenicity, efficacy, safety and tolerability of the vaccines usually recommended in the first years of life in order to help pediatricians choose the best immunisation programme against vaccine-preventable disease in children with cancer receiving standard-dose chemotherapy. Areas for future research are highlighted because new data are required to be able to draw up evidence-based recommendations that will ensure adequate protection against infectious diseases in such high-risk children

Catheter-related infections in pediatric patients with cancer.

Central venous catheters (CVCs) are essential in the management of pediatric patients receiving antineoplastic therapy or bone marrow transplants, and have significantly improved their quality of life, but CVC-related infectious complications are a major source of morbidity. It has been estimated that 14–51 % of the CVCs implanted in children with malignancies may be complicated by bacteremia, and that the incidence of infections is 1.4–1.9 episodes per 1,000 CVC days. However, there are few recent data concerning the epidemiology of CVC-related infections, the prevalence of antimicrobial resistance in their etiology, or the main factors associated with an increased risk of infection by type of catheter, patient age, the type of cancer, or the presence of neutropenia. Moreover, although various new strategies have been proposed in an attempt to reduce the risk of CVC-related infections, such as catheters impregnated with antiseptics/antibiotics, lock antibiotic prophylaxis, the use of ointments at the exit site, and antithrombotic prophylaxis, their real efficacy in children has not yet been demonstrated. The management of CVC-related infections remains difficult, mainly because of the number of still open questions (including the choice of optimal antimicrobial therapy because of the increasing isolation of multiresistant bacterial strains, treatment duration, whether catheters should be removed or not, the feasibility of guidewire exchange, and the usefulness of antibiotic lock therapy) and the lack of studies of children with cancer. Only well-designed, prospective clinical trials involving pediatric cancer patients can clarify optimal prevention and treatment strategies for CVC-related infections in this population

Antibiotic prophylaxis in children with cancer or who have undergone hematopoietic cell transplantation

Bacterial infections are common in children with cancer and can lead to life-threatening complications. Infections in these patients mainly occur during neutropenic periods, and may be caused by Gram-positive or Gram-negative bacteria. The patients at highest risk of serious infections include those with acute lymphoblastic leukemia (ALL) or acute myeloid leukemia (AML), and those undergoing myeloablative hematopoietic cell transplantation (HCT). This is a review with the main aim of making a critical appraisal of the literature, and summarising what is currently known and can be recommended. The most significant studies support the use of floroquinolones (mainly ciprofloxacin) as the most rational approach to treat pediatric patients with probably long-lasting neutropenia, although trimetoprim-sulphametoxazole and amoxicillin/clavulanate may theoretically be valid alternatives. No prophylaxis seems to be needed for children with cancer without severe neutropenia. However, a global evaluation of the studies of antibiotic prophylaxis in children with cancer indicates that there are not enough data to prepare definite guidelines for its use or avoidance in pediatric oncology, and so further studies are needed. It is not only important to define the best antibiotic regimens for the children in whom such prophylaxis is useful, but also to identify precisely those who do not need it. This would avoid the antibiotic misuse that probably occurs at the moment because many low-risk children with cancer are treated. As prophylaxis against infections requires long-term adherence to an antibiotic regimen, the attitudes and beliefs of stakeholders need to be fully considered