Tolerance and humoral immune response to the yellow fever vaccine in sickle cell disease children treated with hydroxyurea: a multicentre prospective study.

BACKGROUND: Sickle cell disease (SCD) children are frequent travellers to countries where yellow fever (YF) is endemic, but there are no data regarding the safety and immunogenicity of the vaccine in such children treated with hydroxyurea (HU). The main objective of this study was to compare the tolerance and immune response to YF vaccination in SCD children treated or not with HU. METHOD: SCD children < 18 years attending the international travel clinics of three large paediatric centres and requiring a first YF vaccination were included in a prospective study. Adverse events were collected 2 weeks after vaccination. YF vaccine antibody titres were measured ~6 months after vaccination. RESULTS: Among the 52 SCD children vaccinated against YF, 17 (33%) were treated with HU. Only mild adverse events, mainly fever and local reaction, were observed in the HU group with a similar frequency in the non-HU group (57 and 35%, respectively, P = 0.30). YF antibody titres were measured in 15/17 patients in the HU group and 23/35 patients in the non-HU group after a median of 6.0 months (3.5-8.5) following vaccination. The geometric mean of YF antibody titre was similar in both groups. A protective antibody level was observed in 85% of the children in the HU group vs 100% in the non-HU group (P = 0.14), suggesting a lower effectiveness of the vaccine in patients on HU similarly to what has been described in patients on immune suppressive therapy for other vaccines. CONCLUSION: YF vaccination seems to be safe and efficient in SCD children treated with HU. Considering the potential risk of severe complications in cases of YF while travelling in Africa for those patients, the benefit-to-risk ratio argues for YF vaccination in all SCD children. Control of a protective antibody titre may also be useful to ascertain an adequate response in those treated with HU.

Pre-hospital management of pediatric polytrauma during modern conflict: experience and limits of the French military health service.

BACKGROUND: French military physicians serving in deployment are confronted with pediatric polytrauma patients (PPP) during the provision of medical aid to civilian populations. The objectives of this study were to describe the current care of PPPs during these missions, to report difficulties encountered and to evaluate the training of doctors for management of PPPs in the field. METHODS: A descriptive epidemiological study based on a questionnaire sent to physicians who had been deployed overseas. RESULTS: 91 doctors participated. Their mean age was 35 years. 86% of the doctors managed children whilst serving overseas, of which 54% were PPPs. The incidence of pediatric polytrauma varied according to the country, but overall from 1129 emergencies reported during overseas missions, 11% were PPPs. Penetrating traumas represented 37% of cases; 24% were circulatory distress and 19% were massive bleeding. 80% of the doctors reported a lack of pediatric trauma experience, less than 5% had received appropriate in-service training and only 9% had worked in pediatric emergency facilities in France. The equipment available for PPPs in the field was often poorly understood and frequently considered to be insufficient. CONCLUSIONS: The occurrence of PPPs of war is rare and complex, but care of older children it is similar to that required for adults. Preparation for PPP management, it could be optimized by identifying risks which alter depending on the country of deployment, such as the logistical organization of the battlefield chain of care. Improvements in doctors' pediatric trauma training should be individualized, based on their mission needs. LEVEL OF EVIDENCE: III.

Severe imported malaria in children in France. A national retrospective study from 1996 to 2005.

BACKGROUNDS: Malaria is a leading cause of imported febrile illnesses in pediatric travelers, but few studies have addressed severe imported pediatric malaria. We aimed to determine the risk factors and the features of imported pediatric severe malaria. METHODS: We conducted a retrospective, descriptive study using the French National Reference Center for Imported Malaria database, in children aged 0-15 years who were hospitalized with a falciparum malaria from January 1st 1996 to December 31th 2005. Uncomplicated and severe cases of falciparum malaria were compared to identify risk factors for severe cases. In the hospitals that reported more than five severe cases during the study period, we evaluated severe cases for prognostic factors and assessed the accuracy WHO criteria for predicting severity. Given the rarity of deaths, adverse outcomes were defined as requiring major therapeutic procedures (MTPs)-e.g., sedation, mechanical ventilation, nasal oxygen therapy, blood transfusions, hemodialysis, fluid resuscitation-or pediatric intensive care unit (PICU) admission. RESULTS: Of 4150 pediatric malaria cases included in the study, 3299 were uncomplicated and 851 (20.5%) were severe. Only one death was recorded during this period. Predictors for severe falciparum malaria were: age <2 years (OR = 3.2, 95% CI = 2.5-4.0, p <0.0001) and a travel in the Sahelian region (OR = 1.7, 95% CI = 1.3-2.0, p = 0.0001). Of 422 severe malaria cases, a stay in a Sahelian region, lack of chemoprophylaxis, age <2 years or thrombocytopenia <100 x 10^3/mm^3 predicted adverse outcomes. Except for the hyperparasitemia threshold of 4%, the main WHO 2000 criteria for severe malaria reliably predicted adverse outcomes. In our study, the threshold of parasitemia most predictive of a poor outcome was 8%. CONCLUSION: In imported pediatric malaria, children younger than 2 years deserve particular attention. The main WHO 2000 criteria for severity are accurate, except for the threshold of hyperparasitemia, which should be revised.

Envenomation by Bothrops atrox in a traveler to Manaus, Brazil.

Snakebites are an infrequent but real risk for travelers. We report a case of envenomation by Bothrops atrox in a traveler to Manaus, Brazil. Rapid administration of specific antivenom prevented the expected systemic disorders. This case gives opportunity to review prevention and first aid measures of snakebites in travelers.