The Wood equation allows consistent fitting of individual antibody-response profiles of Zika virus or SARS-CoV-2 infected patients.

Antibody kinetic curves obtained during a viral infection are often fitted using aggregated patient data, hiding the heterogeneity of individual humoral immune responses. Individual antibody responses can be modeled using the Wood equation and grouped according to their profile. Such modeling takes into account several important kinetic parameters, such as the day when antibody detection becomes positive [daypos], the day of the maximal response [daymax], the maximum antibody level [levelmax], and the day when antibody detection becomes negative [dayneg]. Potential associations between these profiles and studied factors can then be tested.

[Management of the COVID-19 epidemic in the carrier battle group (January-April 2020) by the Armed Forces Epidemiology and Public Health Center]. / Gestion de l'épidémie de COVID-19 au sein du groupe aéronaval (janvier­avril 2020) par le Centre d'épidémiologie et de santé publique des armées.

Objectives: Faced with the COVID-19 epidemic that occurred within the naval air group and the nuclear aircraft carrier Charles de Gaulle, the French Armed Forces Epidemiology and Public Health Center (CESPA) carried out an investigation (January - April 2020) whose objectives were: to identify the possible routes of introduction of the virus ; to describe the characteristics of the epidemic and to describe and model the dynamics of the epidemic's spread. Methods: A telephone survey was conducted. The biological diagnoses were transmitted by the medical antennas. A time/place/population analysis was carried out, as well as the description of the clinical pictures with their exposure factors. The instantaneous reproduction rate Rt of the epidemic was modeled. A spatial analysis of the epidemic on board was carried out. Forty-three viral genomes were sequenced and compared to the reference bases. Results: 0f 1767 sailors, 1568 (89%) participated in the telephone survey and 1064 (67.9%) were confirmed cases. Four patient profiles have been described: asymptomatic (13.0%); non-specific symptomatic (8.1%); specific symptomatic (76.3%); severe cases (2.6%). In univariate and multivariate analysis, age, overweight and obesity were significantly associated with the risk of having a severe form. Smoking was a protective factor. The evolution kinetics of Rt was in favor of an introduction of the virus at the end of February with a reintroduction during the stopover in Brest. Analysis of viral genomes ruled out introduction and spread of a single strain. Conclusion: Despite the control measures taken, an epidemic occurred. The often pauci-symptomatic clinical pictures resulted in a delay in identification. CESPA was able to carry out this epidemiological investigation within a highly constrained timeframe, showing all the interest of its integrated public health model.

Zika virus infections.

Since its discovery in 1947 in Uganda, the Zika virus (ZIKV) remained in the shadows emerging in 2007 in Micronesia, where hundreds of dengue-like syndromes were reported. Then, in 2013-2014, it was rife in French Polynesia, where the first neurological effects were observed. More recently, its arrival in Brazil was accompanied by an unusually high number of children with microcephaly born to mothers infected with ZIKV during the first trimester of pregnancy. In 2016, the World Health Organization declared ZIKV infection to be a public health emergency and now talks about a ZIKV pandemic. This review aims to summarize the current knowledge about ZIKV infection, successively addressing its transmission, epidemiology, clinical aspects, diagnosis, treatment, and prevention before discussing some perspectives.

Feedback on the management of the 2011 measles outbreak by French military general practitioners: an evaluation study.

OBJECTIVE: Preventive measures were implemented in the French armed forces to limit the measles outbreak that occurred in 2010 and 2011. This study aimed to obtain feedback concerning the management of this outbreak by the French military general practitioners. METHOD: A cross-sectional study was conducted among the general practitioners (GPs) in military units located in metropolitan France. The 60 military units that reported at least one measles case in 2011 were included. Data were collected using self-administered questionnaires. RESULTS: The acceptance of preventive measures against measles was good (measures "totally justified" for 77.8%) and most of the military GPs considered that the outbreak had no significant impact on their activities. The management of measles cases was perceived as not very problematic but difficulties were encountered in the identification of contacts around cases (48.1% of respondents) and in the identification of vaccine recipients among these contacts (more than 80% of respondents reporting difficulties in the collection of measles and vaccination histories). The organization of vaccination around cases was also perceived as difficult. CONCLUSIONS: Preventive measures around measles cases were well accepted by the military GPs, which could reflect their preparedness in the face of the outbreak. However, vaccination did not seem to be well understood or accepted by military patients, underlining the essential role of military GPs in patient information. Difficulties in the collection of vaccination and measles histories among contacts could be overcome by an early transcription of individual medical records in the military medical files of newly enlisted personnel. A more generalized use of oral fluid testing devices, which can be shipped at ambient temperature, would simplify diagnosis in the armed forces.

Emergence of Plasmodium ovale malaria among the French Armed Forces in the Republic of Ivory Coast: 20 years of clinical and biological experience.

BACKGROUND: French military surveillance identified an increase in Plasmodium ovale attacks among soldiers in Ivory Coast. This emergence and the low sensitivity of biological tests raise the question of a possible role of P. ovale variant species. METHODS: Epidemiological data about P. ovale attacks from 1993 to 2012 were studied; the species diagnosis was based on a thin blood smear and/or a quick diagnostic test. Clinical and biological features in soldiers hospitalized in 2 French military hospitals were also reviewed. Malaria polymerase chain reaction followed by genotyping was performed when available. RESULTS: French military physicians declared 328 P. ovale attacks over the 20-year study. A peak of incidence occurred in 2005. Among patients with positive blood smears, the quick diagnostic test was positive in 33 of 101 tests performed. The hospital study showed that symptoms and biological changes were not specific, which made diagnosis challenging: fever, anemia, and thrombocytopenia were not present in 20%, 71%, and 23% of the 45 confirmed cases, respectively. It was possible to perform molecular investigations on 19 clinical isolates: 18 were classic haplotypes with additional polymorphism and 1 was variant. CONCLUSIONS: This emergence of P. ovale malaria enabled a good description to be made in nonimmune patients. The lack of sensitivity of both clinical features and quick diagnostic tests suggests an underestimation. Reasons for this outbreak are especially intense exposure to the vectors and the insufficient efficacy of doxycycline against P. ovale. The polymorphism of classic haplotypes of P. ovale rather than variant forms could be involved.

[Epidemics of schistosomiasis in military staff assigned to endemic areas: standard diagnostic techniques and the development of real-time PCR techniques]. / Épidémies de bilharziose chez des militaires projetés en zone d'endémie, techniques de diagnostic classique et mise au point de techniques de réaction en chaîne de la polymérase (PCR) en temps réel.

The authors report the results of molecular biology techniques for the early diagnosis of cases (invasion phase) of schistosomiasis during two epidemics occurring during French military projects in the Central African Republic and Madagascar. The use of these techniques in real time for subjects not residing in the endemic area significantly improves the sensitivity of screening. The attack rates of these episodes, according to a case definition that took positive specific PCR results into account, were 59% and 26%. These results are a concrete illustration of the proverb that "yaws begin where the trail stops".

Malaria attacks due to P. vivax or P. ovale in two French military teaching hospitals (2000 to 2009).

CONTEXT: Non-falciparum malaria is less studied than Plasmodium falciparum malaria, both in endemic and non-endemic zones. PATIENTS AND METHOD: A retrospective study was made of the medical files of patients managed for attacks of malaria due to Plasmodium vivax or Plasmodium ovale, between 2000 and 2009, in two French military teaching hospitals. RESULTS: Seventy-five percent of attacks occurred after a stay in French Guiana, in the Comoros Archipelago, or in the Ivory Coast Republic. The most frequent symptoms two months after coming back were a flu-like syndrome with headaches, and occasional digestive symptoms, without any difference between the first attack and recurrence. One third of patients presented with anemia, 78% with thrombocytopenia, and 12% with liver dysfunction. DISCUSSION: This study was the most important made in France on imported non-falciparum malaria. Military patients and immigrants accounted for a majority of patients due to the specificity of military hospitals and local recruitment. Clinical and biological features were not specific and did not allow guiding the diagnosis. Diagnostic tools were less sensitive for P. ovale. CONCLUSION: Patient management could be optimized by more efficient diagnostic tools, specific guidelines for the diagnostic and therapeutic management, and a dedicated medical training for family practitioners as well as hospitals practice.

A large outbreak of scombroid fish poisoning associated with eating yellowfin tuna (Thunnus albacares) at a military mass catering in Dakar, Senegal.

On 26 November 2010, an outbreak of scombroid fish poisoning occurred in the French Armed Forces in Dakar, Senegal. This chemical intoxication, due to high histamine concentration in fish, is often mistaken for an allergic reaction. A case-control study was undertaken including the 71 cases and 78 randomly selected controls among lunch attendees. The usual symptoms for scombroid fish poisoning were observed in cases, i.e. flushing (85.9%), headache (83.1%), rapid/weak pulse (59.1%) and diarrhoea (47.9%). Symptoms occurred from within a few minutes to up to 3 h following the meal. Most patients quickly recovered with antihistamine and/or symptomatic treatment. Tuna was the only food item positively associated with illness (odds ratio 36.3, 95% confidence interval 6.3-210.0), with the risk of illness increasing with the quantity of fish consumed. No bacterial contamination was found in leftover food, but histamine concentration in tuna was found to be 4900 mg/kg, almost 50-fold higher than the concentration allowed by European regulations. This report is unique because of the large size of the case series - to our knowledge, the largest event of scombroid fish poisoning ever reported - and the chemical and bacteriological analyses results obtained on leftover food.

Increase in reported adverse events following seasonal influenza vaccination among the French armed forces, 2008-2009: possible role of stimulated reporting and background cases of influenza-like infection.

OBJECTIVES: In September 2009, an increase in seasonal influenza vaccine adverse events (VAE), compared with reports for previous years, was detected among the French armed forces in the setting of an extended immunization campaign. This work presents the results of this investigation. STUDY DESIGN: VAE were surveyed among all French military personnel from 2008 to 2009 by Epidemiological Departments of the French Military Health Service. For each case, a notification form was completed, providing patient and clinical information. METHODS: Case definitions were derived from the French drug vigilance guidelines. Three types of VAE were considered: non-serious, serious and unexpected. Incidence rates were calculated by relating VAE to the number of vaccine doses injected. RESULTS: Forty-seven seasonal influenza VAE were reported in continental France: 18 in 2008 and 29 in 2009. The annual reporting rate was higher in 2009 (31.6 vs 16.6 VAE per 100,000 injections, respectively). The highest monthly incidence was observed in September 2009 (60.8 events per 100,000 injections). Two other peaks were observed in February 2008 and March 2009. The incidence in September 2009 was not significantly different from the incidences in February 2008 and March 2009. It was observed that incidence peaks occurred during influenza epidemic periods. One serious neurological VAE was observed. CONCLUSIONS: The increase in seasonal influenza VAE in late 2009 mainly involved non-serious events, and could reflect stimulated reporting in the context of the A(H1N1)pdm09 pandemic. VAE reporting rates were highest during influenza epidemic periods, which could be explained by VAE being wrongly attributed to the vaccine when symptoms could reflect coincident background cases of viral infection.

Resurgence of measles in the French military forces in 2010.

Since the start of 2010 there has been a flare-up of measles in France, following on the resurgence observed in 2008. The aim of this study was to present results of the epidemiological surveillance of measles in the French armed forces and to describe the increase in incidence. Measles was surveyed from 1992 to 2010. Criteria for report were those used for French national compulsory notification. The data, concerning active military personnel, were provided by the physicians in the armed forces using anonymous data collection forms. Between 1992 and July 2010, 689 cases of measles were notified. Since 2002, the mean incidence rate was 1 case per 100,000. A significant increase has been observed for 2010 (13.9 cases per 100,000 in 2010 versus 1.8 in 2009). The 28 cases reported in 2010 involved five clusters and three isolated cases. The mean age of affected subjects was 27 years. Only 30% of cases had been vaccinated. The epidemic resurgence of measles observed in 2010 in the French armed forces follows the same pattern as that observed nationally and at European level, and can be seen as the likely consequence of inadequate vaccination cover.

[A(H1N1) influenza surveillance in the French armed forces: adapting the surveillance systems to the pandemic setting]. / Surveillance épidémiologique de la grippe A(H1N1) 2009 dans les armées françaises: adaptation des systèmes de surveillance au contexte pandémique.

OBJECTIVES: An outbreak of A(H1N1) virus influenza, detected in Mexico during April 2009, spread around the world in nine weeks. French armed forces had to adapt their epidemiological surveillance systems to this pandemic. Our aim was to present surveillance results. DESIGN: There are two influenza surveillance systems in French armed forces: one permanent throughout the year and one seasonal, the Military influenza surveillance system (SMOG). The pandemic threat led to an early reactivation of SMOG, before the initiation of a daily surveillance system specifically dedicated to A(H1N1) influenza. RESULTS: In metropolitan France, the increase of respiratory infections was observed as of September 2009, with a maximum of 401 cases for 100,000 at the beginning of December according to SMOG. The estimated rate of consultations related to A(H1N1) influenza ranged between 46 and 65 cases for 100,000. For military units operating outside of metropolitan France, a peak of incidence was observed in August (400 cases for 100,000). CONCLUSION: The trends observed by influenza military surveillance networks were compatible with French ones. Concerning French forces in operations, the increase of incidence observed in August was the consequence of the influenza outbreak in the Southern hemisphere. Estimations of consultations rate related to A(H1N1) influenza, ranged between 127 and 194 cases for 100,000 at the beginning of December, lower than the national rate (1321 cases for 100,000), a consequence of the age pyramid in the military population.