Evaluating the serological status of COVID-19 patients using an indirect immunofluorescent assay, France.

An indirect in-house immunofluorescent assay was developed in order to assess the serological status of COVID-19 patients in Marseille, France. Performance of IFA was compared to a commercial ELISA IgG kit. We tested 888 RT-qPCR-confirmed COVID-19 patients (1302 serum samples) and 350 controls including 200 sera collected before the pandemic, 64 sera known to be associated with nonspecific serological interference, 36 sera from non-coronavirus pneumonia and 50 sera from patient with other common coronavirus to elicit false-positive serology. Incorporating an inactivated clinical SARS-CoV-2 isolate as the antigen, the specificity of the assay was measured as 100% for IgA titre ≥ 1:200, 98.6% for IgM titre ≥ 1:200 and 96.3% for IgG titre ≥ 1:100 after testing a series of negative controls. IFA presented substantial agreement (86%) with ELISA EUROIMMUN SARS-CoV-2 IgG kit (Cohen's Kappa = 0.61). The presence of antibodies was then measured at 3% before a 5-day evolution up to 47% after more than 15 days of evolution. We observed that the rates of seropositivity as well as the titre of specific antibodies were both significantly higher in patients with a poor clinical outcome than in patients with a favourable evolution. These data, which have to be integrated into the ongoing understanding of the immunological phase of the infection, suggest that detection anti-SARS-CoV-2 antibodies is useful as a marker associated with COVID-19 severity. The IFA assay reported here is useful for monitoring SARS-CoV-2 exposure at the individual and population levels.

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry as a useful tool for the rapid identification of wild flea vectors preserved in alcohol.

Flea identification is a significant issue because some species are considered as important vectors of several human pathogens that have emerged or re-emerged recently, such as Bartonella henselae (Rhizobiales: Bartonellaceae) and Rickettsia felis (Rickettsiales: Rickettsiaceae). Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been evaluated in recent years for the identification of multicellular organisms, including arthropods. A preliminary study corroborated the usefulness of this technique for the rapid identification of fleas, creating a preliminary database containing the spectra of five species of flea. However, longterm flea preservation in ethanol did not appear to be an adequate method of storage in the context of specimen identification by MALDI-TOF MS profiling. The goal of the present work was to assess the performance of MALDI-TOF MS in the identification of seven flea species [Ctenocephalides felis (Siphonaptera: Pulicidae), Ctenocephalides canis, Pulex irritans (Siphonaptera: Pulicidae), Archaeopsylla erinacei (Siphonaptera: Pulicidae), Leptopsylla taschenbergi (Siphonaptera: Ceratophyllidae), Stenoponia tripectinata (Siphonaptera: Stenoponiidae) and Nosopsyllus fasciatus (Siphonaptera: Ceratophyllidae)] collected in the field and stored in ethanol for different periods of time. The results confirmed that MALDI-TOF MS can be used for the identification of wild fleas stored in ethanol. Furthermore, this technique was able to discriminate not only different flea genera, but also the two congeneric species C. felis and C. canis.

Anti-feeding and insecticidal efficacy of a topical administration of dinotefuran-pyriproxyfen-permethrin spot-on (Vectra® 3D) on mice against Stegomyia albopicta (= Aedes albopictus).

An ectoparasiticide combining three active ingredients [dinotefuran, permethrin and pyriproxyfen (DPP)] was used in mice in an experiment designed to evaluate its anti-feeding and insecticidal efficacy against Stegomyia albopicta (= Aedes albopictus) (Diptera: Culicidae) mosquitoes. Twenty-two adult mice were randomly allocated into two groups consisting of an untreated control group and a DPP-treated group. Mice were exposed individually for 1 h to a mean ± standard deviation of 27 ± 2 starved female mosquitoes on days 1, 7, 14, 21 and 28 post-treatment. At the end of the exposure (1 h), mosquitoes were assessed for immediate survival and engorgement status. Additionally, live mosquitoes in both groups were incubated separately and observed for mortality at 24 h after the end of the exposure. The anti-feeding efficacy of DPP after the 1-h exposure period was 99.2, 100, 98.0, 89.3 and 87.4% at 1, 7, 14, 21 and 28 days, respectively. Levels of insecticidal efficacy evaluated at 1 h and 24 h after exposure on days 1, 7, 14, 21 and 28 were 36.7, 28.9, 30.8, 23.1 and 11.9%, and 68.4, 45.0, 43.3, 37.9 and 19.9%, respectively. Based on the mouse model, the present study demonstrates that the DPP combination has significant anti-feeding and insecticidal efficacy against S. albopicta for at least 4 weeks.

Comparative analysis of storage conditions and homogenization methods for tick and flea species for identification by MALDI-TOF MS.

Ticks and fleas are vectors for numerous human and animal pathogens. Controlling them, which is important in combating such diseases, requires accurate identification, to distinguish between vector and non-vector species. Recently, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was applied to the rapid identification of arthropods. The growth of this promising tool, however, requires guidelines to be established. To this end, standardization protocols were applied to species of Rhipicephalus sanguineus (Ixodida: Ixodidae) Latreille and Ctenocephalides felis felis (Siphonaptera: Pulicidae) Bouché, including the automation of sample homogenization using two homogenizer devices, and varied sample preservation modes for a period of 1-6 months. The MS spectra were then compared with those obtained from manual pestle grinding, the standard homogenization method. Both automated methods generated intense, reproducible MS spectra from fresh specimens. Frozen storage methods appeared to represent the best preservation mode, for up to 6 months, while storage in ethanol is also possible, with some caveats for tick specimens. Carnoy's buffer, however, was shown to be less compatible with MS analysis for the purpose of identifying ticks or fleas. These standard protocols for MALDI-TOF MS arthropod identification should be complemented by additional MS spectrum quality controls, to generalize their use in monitoring arthropods of medical interest.

Assessment of the anti-feeding and insecticidal effects of the combination of dinotefuran, permethrin and pyriproxyfen (Vectra® 3D) against Triatoma infestans on rats.

This study, based on the rat model, was designed to explore the anti-feeding and insecticidal efficacy of a topical ectoparasiticide, dinotefuran-permethrin-pyriproxyfen (DPP), against Triatoma infestans (Hemiptera: Reduviidae), a vector of Trypanosoma cruzi (Trypanosomatida: Trypanosomatidae), for which dogs are domestic reservoir hosts. Twenty rats were divided into two equal groups: untreated and treated. Each rat was exposed under sedation to 16 T. infestans of mixed life stages for 1 h on days 1, 7, 14, 21 and 28 post-treatment. The anti-feeding and insecticidal effects of DPP were estimated after 1 h of exposure. Insecticidal efficacy was also assessed after incubation of the insects for 24 h post-exposure. Anti-feeding efficacy was 96.7, 84.7, 80.5, 81.5 and 42.6% on days 1, 7, 14, 21 and 28, respectively. Insecticidal efficacy evaluated at 1 and 24 h after exposure on days 1, 7, 14, 21 and 28 was 100, 91.2, 82.5, 80.0 and 29.1, and 100, 100, 100, 96.0 and 49.9%, respectively. This study demonstrates that a single administration of DPP spot-on treatment at a dose equivalent to the minimal recommended dose in rats has a powerful effect against T. infestans starting from day 1 that lasts for at least 3 weeks.

[Update on cutaneous dirofilariasis]. / La dirofilariose cutanée.

Dirofilariasis is a worldwide zoonotic infection that rarely affects humans and is caused by filarial nematodes of the genus Diroflaria transmitted by mosquitoes. Cutaneous dirofilariasis, due to D. repens, presents as inflammatory lesions that develop into subcutaneous nodules. These clinical symptoms may be consistent with Wells' cellulitis. Diagnosis of dirofilariasis involves demonstration of the presence of the nematode during skin biopsy and identification of the worm through macroscopic, histological and PCR analysis. Surgical resection of the nodule remains the gold standard treatment. The number of cases of human cutaneous dirofilariasis has increased in the recent years and the disease must not be misdiagnosed.

Cutaneous and pulmonary dirofilariasis due to Dirofilaria repens.

Dirofilariasis is a worldwide zoonotic infection that accidentally affects humans. It is caused by filarial nematodes of the genus Dirofilaria, which are transmitted by mosquitoes. Cutaneous dirofilariasis appears as inflammatory lesions that could be consistent with Wells' cellulitis. We present a remarkable case of human infection with Dirofilaria repens, causing both subcutaneous and pulmonary nodules.

Dramatic reduction in Clostridium difficile ribotype 027-associated mortality with early fecal transplantation by the nasogastric route: a preliminary report.

Clostridium difficile ribotype 027 (CD027)-associated diarrhea preferentially affects elderly patients and causes a high mortality rate. Fecal microbiota transplantation has become an alternative treatment for recurrent C. difficile infections. An outbreak of CD027 infections has occurred in Marseille since March 2013. From March to November 2013, we treated patients using only antibiotics or fecal microbiota transplantation after at least three relapses. Beginning in November 2013, we performed early transplantation using a nasogastric tube during the first week of infection, in combination with antibiotic treatment. Sixty-one patients with a mean age of 84 years were hospitalized, including 42 patients treated only with antibiotics, three with tardive transplantation, and 16 with early transplantation. The patients were comparable in clinical involvement. The global mortality rate was 3/16 (18.75 %) among the patients treated by early transplantation and 29/45 (64.4 %) among the patients only treated by antibiotics or by tardive transplantation (p < 0.01). Among these 45 patients, 23 (51 %) died at day 31, including 17 who died at day 7. Early fecal transplantation was associated with a significantly reduced mortality rate, with only one patient dead at day 31 (6.25 %). In a Cox model, early transplantation was the only independent predictor of survival (hazard ratio 0.18, 95 % confidence interval 0.05-0.61, p = 0.006). Six of the 16 patients (37.5 %) needed a second transplantation before symptom resolution. Early fecal microbiota transplantation in combination with antibiotics should be the first-line treatment for CD027 infections.

Responses of artificially reared cat fleas Ctenocephalides felis felis (Bouché, 1835) to different mammalian bloods.

The cat flea, Ctenocephalides felis felis (Bouche, 1835) (Siphonaptera: Pulicidae), which is found worldwide and which parasitizes many species of wild and domestic animal, is a vector and/or reservoir of bacteria, protozoa and helminths. To aid in the study of the physiology and behaviour of fleas and of their transmission of pathogens, it would be of value to improve the laboratory rearing of pathogen-free fleas. The conditions under which artificially reared fleas at the University of Bristol (U.K.) and the Rickettsial Diseases Institute (France) are maintained were studied, with different ratios of male to female fleas per chamber (25 : 50, 50 : 100, 100 : 100, 200 : 200). The fleas were fed with bovine, ovine, caprine, porcine or human blood containing the anticoagulants sodium citrate or EDTA. Egg production was highest when fleas were kept in chambers with a ratio of 25 males to 100 females. In addition, the use of EDTA as an anticoagulant rather than sodium citrate resulted in a large increase in the number of eggs produced per female; however, the low percentage of eggs developing through to adult fleas was lower with EDTA. The modifications described in our rearing methods will improve the rearing of cat fleas for research.

New Delhi Metallo-beta-lactamase around the world: an eReview using Google Maps.

Gram-negative carbapenem-resistant bacteria, in particular those producing New Delhi Metallo-betalactamase-1 (NDM-1), are a major global health problem. To inform the scientific and medical community in real time about worldwide dissemination of isolates of NDM-1-producing bacteria, we used the PubMed database to review all available publications from the first description in 2009 up to 31 December 2012, and created a regularly updated worldwide dissemination map using a web-based mapping application. We retrieved 33 reviews, and 136 case reports describing 950 isolates of NDM-1-producing bacteria. Klebsiella pneumoniae (n= 359) and Escherichia coli (n=268) were the most commonly reported bacteria producing NDM-1 enzyme. Several case reports of infections due to imported NDM-1 producing bacteria have been reported in a number of countries, including the United Kingdom, Italy, and Oman. In most cases (132/153, 86.3%), patients had connections with the Indian subcontinent or Balkan countries. Those infected were originally from these areas, had either spent time and/or been hospitalised there, or were potentially linked to other patients who had been hospitalised in these regions. By using Google Maps, we were able to trace spread of NDM-1-producing bacteria. We strongly encourage epidemiologists to use these types of interactive tools for surveillance purposes and use the information to prevent the spread and outbreaks of such bacteria.

Hajj pilgrims knowledge about Middle East respiratory syndrome coronavirus, August to September 2013.

In preparation for Hajj 2013, 360 French pilgrims were interviewed regarding their knowledge about Middle East respiratory syndrome (MERS). Respondents were aged 20­85 years, male-female ratio was 1.05:1;64.7% were aware of the MERS situation in Saudi Arabia; 35.3% knew about the Saudi Ministry of Health recommendations for at-risk pilgrims to postpone participation in the 2013 Hajj. None of 179 at-risk individuals(49.9%) decided to cancel their Hajj participation even after advice during consultation.

Ongoing outbreak of an acute muscular Sarcocystis-like illness among travellers returning from Tioman Island, Malaysia, 2011-2012.

As of 4 November, 2012, 100 patients with an acute muscular Sarcocystis-like illness associated with travel to Tioman Island, Malaysia, have been identified. Thirty-five travelled there mostly during July and August 2011 and 65 mostly during July and August 2012, suggesting an ongoing outbreak. Epidemiological investigations are ongoing. Public health agencies and practicing clinicians should be aware of this rarely-reported disease in humans and consider it as differential diagnosis in travellers returning from Tioman Island.

2012 outbreak of acute haemorrhagic conjunctivitis in Indian Ocean Islands: identification of Coxsackievirus A24 in a returned traveller.

In May 2012, a Coxsackievirus A24 haemorrhagic conjunctivitis was diagnosed in Marseille, France, in a traveller returning from the Comoros Islands. This case allowed identification of the cause of an ongoing outbreak of haemorrhagic conjunctivitis in Indian Ocean Islands, illustrating that returning travellers may serve as sentinels for infectious diseases outbreaks in tropical areas where laboratory investigation is limited.

Infectious diseases among travellers and migrants in Europe, EuroTravNet 2010.

To investigate trends in travel-associated morbidity with particular emphasis on emerging infections with the potential for introduction into Europe, diagnoses of 7,408 returning travellers presenting to 16 EuroTravNet sites in 2010 were compared with 2008 and 2009. A significant increase in reported Plasmodium falciparum malaria (n=361 (6% of all travel-related morbidity) vs. n=254 (4%) and 260 (5%); p<0.001), P. vivax malaria (n=51 (1%) vs. n=31 (0.5%) and 38 (1%); p=0.027) and dengue fever (n=299 (5%) vs. n=127 (2%) and 127 (2%); p<0.001) was observed. Giardia lamblia was identified in 16% of patients with acute diarrhoea, with no significant annual variation. The proportion of acute diarrhoea due to Campylobacter increased from 7% in 2008 to 12% in 2010 (p=0.001). We recorded 121 patients with pulmonary tuberculosis in 2010, a threefold increase in the proportionate morbidity from 2008 to 2010. In 2010, 60 (0.8%) cases of chronic Chagas disease, 151 (2%) cases of schistosomiasis and 112 (2%) cases of cutaneous larva migrans were reported. Illness patterns in sentinel travellers, captured by EuroTravnet, continue to highlight the potential role of travellers in the emergence of infectious diseases of public health concern in Europe and the relevance of offering medical travel advice and enforcing specific and adequate prophylaxis.

[Rickettsial diseases in Switzerland, update for the general practitioner]. / Rickettsioses d'importation.

Rickettsial diseases are arthropod-borne zoonosis. They are still misdiagnosed in Switzerland. Since development in molecular genetics, number of pathogenic species increased dramatically. In recent years, the incidence rise worldwide. Climatic conditions and development of tropical travels could explain it. In a near future, the Swiss general practitioner may face an increase of cases. Clinical presentation is unspecified. The eschar is the key diagnostic element but can be easily overlooked. Serology, the indirect immunofluorescence assay is the reference method. PCR can give the diagnosis in acute phase. However empirical treatment should be prescribed as soon as diagnosis is suspected. No vaccine is currently available and use of repellent is still the best way of prevention.

Bartonella clarridgeiae, B. henselae and Rickettsia felis in fleas from Morocco.

A total of 554 fleas were collected in the Moroccan Casablanca and Tiznit regions from domesticated animals and ruminants between August 2007 and October 2008 and were tested for the presence of Rickettsia spp. and Bartonella spp. using molecular methods. For the first time in Morocco, we found Rickettsia felis, the agent of flea-borne spotted fever in Ctenocephalides felis; B. henselae, an agent of cat scratch disease; and Bartonella clarridgeiae, a cat pathogen and potentially a human pathogen.

Imported extensively drug-resistant Mycobacterium tuberculosis Beijing genotype, Marseilles, France, 2011.

Multidrug- (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) are reported to gradually spread across European countries with low TB prevalence including France. Some isolates may even accumulate traits of resistance in addition to the XDR profile, as a result of therapeutic mismanagement. We report here the first case of XDR TB in Marseilles and discuss the potential effectiveness of sulfamide treatment in such cases.

Plasmodium vivax malaria in a Romanian traveller returning from Greece, August 2011.

In August 2011, a Plasmodium vivax malaria infection was diagnosed in a Romanian traveller returning from Greece. This case together with several reports over the past decade of autochthonous cases in Greece highlight that malaria should be considered as differential diagnosis in symptomatic travellers returning from this country. Travellers may serve as sentinels of emerging vector-borne diseases.

EuroTravNet: imported Chagas disease in nine European countries, 2008 to 2009.

In recent years, Chagas disease has emerged as a disease of importance outside of endemic areas, largely as a result of migration. In Europe, clinicians may have to treat infected migrants from endemic areas as well as people with acute infections transmitted congenitally,through organ donation or blood transfusion.We describe here the characteristics of patients diagnosed with chronic Chagas disease at the core clinical sites of the EuroTravNet network during 2008 and 2009. Of the 13,349 people who attended the sites, 124 had chronic Chagas disease. Most (96%) were born in Bolivia and the median number of months in the country of residence before visiting a EuroTravNet core site was 38 months (quartile (Q1)­Q3: 26­55). The median age of the patients was 35 years (Q1­Q3: 29­45) and 65% were female. All but one were seen as outpatients and the most frequent reason for consultation was routine screening. Considering that Chagas disease can be transmitted outside endemic regions and that there is effective treatment for some stages of the infection, all migrants from Latin America (excluding the Caribbean) should be questioned about past exposure to the parasite and should undergo serological testing if infection is suspected.

[Snake bites in the emergency unit of Niamey National Hospital, Niger]. / Morsures de serpent à l'hôpital national de Niamey: à propos de 53 cas.

This study was aimed at assessing envenomations caused by snakebite in Niamey National Hospital, between July 2005 and September 2006. We included 53 victims of snakebites. The wounded distribution indicated more wounded males than females (sex ratio = 1.78:1). The mean age was 29 ± 17 years. September to November seemed a period of higher risk. The snake was not identified in 60% of the cases. The bite occurred during March in 43% of the cases. Clinically, 6% of the patients showed no signs of envenomation and 7% presented bleeding disorders; 88% of the patients did not receive anti-venom. The lethality rate was 15%.