Diphtheria in Europe.

A rising number of diphtheria cases were recorded in Europe in 2022, including in Belgium, within the newly arriving young migrant population. In October 2022, Médecins Sans Frontières (MSF) opened a temporary roadside container-clinic offering free medical consultations. Over 3 months of activity, the temporary clinic detected 147 suspected cases of cutaneous diphtheria with 8 laboratory-confirmed cases growing toxigenic Corynebacterium diphtheriae. This was followed by a mobile vaccination campaign, during which 433 individuals living rough in squats and informal shelters were vaccinated. This intervention has shown how even in Europe's capital, access to preventive and curative medical services remains difficult for those who need it the most. Appropriate access to health services, including routine vaccination, are crucial to improve the health status among migrants.

Un nombre croissant de cas de diphtérie a été enregistré en Europe en 2022, y compris en Belgique, au sein de la population de jeunes migrants nouvellement arrivés. En octobre 2022, Médecins Sans Frontières (MSF) a ouvert un conteneur-clinique temporaire en bord de route offrant des consultations médicales gratuites. En 3 mois d'activité, la clinique temporaire a détecté 147 cas suspects de diphtérie cutanée et 8 cas confirmés en laboratoire de Corynebacterium diphtheriae toxigène. Cette opération a été suivie d'une campagne de vaccination mobile, au cours de laquelle 433 personnes vivant dans la rue, dans des squats et des abris informels, ont été vaccinées. Cette intervention a montré que même dans la capitale de l'Europe, l'accès aux services médicaux préventifs et curatifs reste difficile pour ceux qui en ont le plus besoin. Un accès adéquat aux services de santé, y compris une vaccination de routine, est primordial pour améliorer l'état de santé des migrants.

Field challenges to measles elimination in the Democratic Republic of the Congo.

BACKGROUND: During a measles epidemic, the Ministry of Public Health (MOH) of the Democratic Republic of the Congo conducted supplementary immunization activities (2016-SIA) from August 28-September 3, 2016 throughout Maniema Province. From October 29-November 4, 2016, Médecins Sans Frontières and the MOH conducted a reactive measles vaccination campaign (2016-RVC) targeting children six months to 14 years old in seven health areas with heavy ongoing transmission despite inclusion in the 2016-SIA, and a post-vaccination survey. We report the measles vaccine coverage (VC) and effectiveness (VE) of the 2016-SIA and VC of the 2016-RVC. METHODS: A cross-sectional VC cluster survey stratified by semi-urban/rural health area and age was conducted. A retrospective cohort analysis of measles reported by the parent/guardian allowed calculation of the cumulative measles incidence according to vaccination status after the 2016-SIA for an estimation of crude and adjusted VE. RESULTS: In November 2016, 1145 children (6-59 months old) in the semi-urban and 1158 in the rural areas were surveyed. Post-2016-SIA VC (documentation/declaration) was 81.6% (95%CI: 76.5-85.7) in the semi-urban and 91.0% (95%CI: 84.9-94.7) in the rural areas. The reported measles incidence in October among children less than 5 years old was 5.0% for 2016-SIA-vaccinated and 11.2% for 2016-SIA-non-vaccinated in the semi-urban area, and 0.7% for 2016-SIA-vaccinated and 4.0% for 2016-SIA-non-vaccinated in the rural area. Post-2016-SIA VE (adjusted for age, sex) was 53.9% (95%CI: 2.9-78.8) in the semi-urban and 78.7% (95%CI: 0-97.1) in the rural areas. Post 2016-RVC VC (documentation/declaration) was 99.1% (95%CI: 98.2-99.6) in the semi-urban and 98.8% (95%CI: 96.5-99.6) in the rural areas. CONCLUSIONS: Although our VE estimates could be underestimated due to misclassification of measles status, the VC and VE point estimates of the 2016-SIA in the semi-urban area appear suboptimal, and in combination, could not limit the epidemic. Further research is needed on vaccination strategies adapted to urban contexts.

[Multiple Ebola virus haemorrhagic fever outbreaks in Gabon, from October 2001 to April 2002]. / Plusieurs epidémies de fièvre hémorragique due au virus Ebola au Gabon, d'octobre 2001 a avril 2002.

Outbreaks of Ebola virus haemorrhagic fever have been reported from 1994 to 1996 in the province of Ogooué Ivindo, a forest zone situated in the Northeast of Gabon. Each time, the great primates had been identified as the initial source of human infection. End of November 2001 a new alert came from this province, rapidly confirmed as a EVHV outbreak. The response was given by the Ministry of Health with the help of an international team under the aegis of WHO. An active monitoring system was implemented in the three districts hit by the epidemic (Zadié, Ivindo and Mpassa) to organize the detection of cases and their follow-up. A case definition has been set up, the suspected cases were isolated at hospital, at home or in lazarets and serological tests were performed. These tests consisted of the detection of antigen or specific IgG and the RT-PCR. A classification of cases was made according to the results of biological tests, clinical and epidemiological data. The contact subjects were kept watch over for 21 days. 65 cases were recorded among which 53 deaths. The first human case, a hunter died on the 28th of October 2001. The epidemic spreads over through family transmission and nosocomial contamination. Four distinct primary foci have been identified together with an isolated case situated in the South East of Gabon, 580 km away from the epicenter. Deaths happened within a delay of 6 days. The last death has been recorded on the 22nd of March 2002 and the end of the outbreak was declared on the 6th of May 2002. The epidemic spreads over the Gabon just next. Unexplained deaths of animals had been mentionned in the nearby forests as soon as August 2001: great primates and cephalophus. Samples taken from their carcasses confirmed a concomitant animal epidemic.

[Management of cholera epidemics in a refugee camp]. / Prise en charge des épidémies de choléra dans un camp de réfugiés.

Cholera epidemics in refugee camps represent a major public health emergency. In camps, precarious living conditions contribute to the transmission of the vibrio. Among the major epidemics reported in camps, we note as well those which have affected Africa in the last two decades. These epidemics are characterized by high attack rates and high case fatality ratios. Attack rates in refugee camps can exceed 5%. Appropriate control measures are adopted at international level. Actions carried out urgently must allow the proper supply of water, the control of excreta, and the improvement of general sanitary conditions and individual hygiene. Efficient management of cases in specialized cholera treatment centres (CTC) should decrease the case fatality ratio to less than 1%. Treatment is mainly based on the prompt rehydration of patients. For wide camps, rapid access to oral rehydration units is essential. Availability of all necessary equipment in kit form is required.

Conformational nature of the Borrelia burgdorferi decorin binding protein A epitopes that elicit protective antibodies.

Decorin binding protein A (DbpA) has been shown by several laboratories to be a protective antigen for the prevention of experimental Borrelia burgdorferi infection in the mouse model of Lyme borreliosis. However, different recombinant forms of the antigen having either lipidated amino termini, approximating the natural secretion and posttranslational processing, or nonprocessed cytosolic forms have elicited disparate levels of protection in the mouse model. We have now used the unique functional properties of this molecule to investigate the structural requirements needed to elicit a protective immune response. Genetic and physicochemical alterations to DbpA showed that the ability to bind to the ligand decorin is indicative of a potent immunogen but is not conclusive. By mutating the two carboxy-terminal nonconserved cysteines of DbpA from B. burgdorferi strain N40, we have determined that the stability afforded by the putative disulfide bond is essential for the generation of protective antibodies. This mutated protein was more sensitive to thermal denaturation and proteolysis, suggesting that it is in a less ordered state. Immunization with DbpA that was thermally denatured and functionally inactivated stimulated an immune response that was not protective and lacked bactericidal antibodies. Antibodies against conformationally altered forms of DbpA also failed to kill heterologous B. garinii and B. afzelii strains. Additionally, nonsecreted recombinant forms of DbpA(N40) were found to be inferior to secreted lipoprotein DbpA(N40) in terms of functional activity and antigenic potency. These data suggest that elicitation of a bactericidal and protective immune response to DbpA requires a properly folded conformation for the production of functional antibodies.

Hypertension after renal transplantation.

The incidence of hypertension (mean diastolic pressure above 90 mm Hg) was evaluated in 85 patients with renal transplants whose follow-up ranged from 3 to 84 months. Bilateral nephrectomy had been performed in 80 recipients. The proportion of hypertensive subjects rose during the first three months, subsequently stabilised around 50-60% for up to five years, and then decreased slightly during the next two years. Over the years hypertension fluctuated so that one-third of the initially hypertensive patients became normotensive, and over one-third of the initially normotensive patients became hypertensive. The main single aetiological factor was renal failure. A significant relation between steroid dosage and blood pressure was found in only a quarter of the hypertensive patients, and in another quarter no cause could be found.

[Analysis of the electrophysiological effects of amiodarone using simultaneous recordings of monophasic and bundle-of-his action potentials]. / Analyse des effets électrophysiologiques de l'amiodarone par l'enregistrement simultané des potentiels d'action monophasiques et du faisceau de His

The effects of amiodarone given by rapid intravenous injection at a dosage of 10 mg/kg have been studied in the dog. The peak activity is found between the fifth and the tenth minute. The rate of discharge of the sinus is lowered by 36%. At the atrial level, the duration of the monophasic action potential (MAP) is increased by 9% and its dv/dt is lowered slightly, the total refractory period is increased by 22%, the effective refractory period is increased by 27%, the functional refractory period is increased by 19%, the ratio of the length of the effective period/duration of the MAP becomes slightly greater than unity, conduction facilitation disappears, and the period of slow conduction increases. In the A/V node the AH interval increases by 44% under normal rhythm, while atrial stimulation at 200/min. results in conversion to total AV block in more than half of the cases. The potential of the bundle of His and the HV interval are not altered. At ventricular level the duration of the monophasic action potential increases by 25%, its dv/dt decreases slightly, the total refractory period is increased by 8%, and the effective refractory period is increased by 14%.

Hypertension after renal transplantation.

The incidence of hypertension defined as a mean diastolic pressure above 90 mmHg has been evaluated in 85 transplanted patients with a follow-up ranging from 3 to 78 months. The proportion of hypertensive patients rises during the first three months and stabilises subsequently around 60 percent. Over the years hypertension fluctuates so that one-third of the initially hypertensive patients become normotensive, whereas one-third of the initially normotensive patients become hypertensive. The main single aetiological factor is renal failure. No clear relationship was found between prednisolone dosage and hypertension. Renal artery stenosis was found in 2.4 percent of the cases. Finally no single aetiological factor was found in one third of the hypertensive patients. It is speculated that in some of them, minute intrarenal vascular lesions are responsible for the hypertension and lead ultimately to decreased renal function.