[Anthropocene and Emerging viral diseases]. / Anthropocène et viroses émergentes.

We propose to bring together the new geologic concept of Anthropocene and its consequences on our environment with the observed increasing emergence of new viruses - a pathogen for both humans and animals, mainly since the mid of the twentieth century.

[Middle East respiratory syndrome (MERS): bats or dromedary, which of them is responsible?]. / Le « syndrome respiratoire du Moyen-Orient ¼ (MERS) : qui est responsable, les chauves-souris ou le dromadaire ?

In 2012 a new viral emergent human disease appeared in the Middle East. This entity was named MERS for' Middle East respiratory syndrome'. By January 9, 2014, the disease had already struck 178 persons of whom 75 died from respiratory failure and diarrhoea. As the new disease was very similar to the deadly SARS (2002-2003) and since it was provoked by a Betacoronavirus, chiroptera were first suspected to be at the origin of this infection. Morever, recent studies performed in Saudi Arabia showed that one individual of the bat Taphozous perforatus harbored a short nucleotide segment identical to the homologous segment present in the viral strain isolated from the index-case of the epidemic. In addition, many strains of Betacoronavirus more or less related to those responsible for the MERS disease in man have been isolated from bats in Africa, Asia and Europe. However, another hypothesis was simultaneously proposed incriminating dromedary (Camelus dromedarius L.) as a likely actor in the transmission to human beings of the disease.We then reviewed data relative to other viral zoonosis in which dromedary was possibly implicated. This led to the provisional conclusion that this large mammal might play a role in the dissemination of the MERS-COV, the etiologic agent of the disease. This is based on epidemiological data and results of several serological surveys in animals.

[About a note published in 1926 on a BCG vaccine trial in leprosy treatment]. / À propos d'une note de 1926 sur un essai du BCG dans le traitement de la lèpre.

By 1926, two French physicians working in Indochina, R. Pons and L. Chastel, have suggested to treat leprosy by subcutaneous injections of bacillus Calmette-Guerin. This treatment appeared efficient since the lepromatous lesions quickly regressed and the Hansen bacillus disappeared from the nasal mucus. These results were quickly confirmed by other authors. They were all more appreciated than, at this time, the Chaulmoogra oil and its products, the only available drugs, were poorly efficient against the disease. Nevertheless, although not a panacea, the BCG therapy allowed to relieve these unfortunate patients until the beginning of the 1950's when an effective treatment by sulfones was at length available.

[When some Flaviviruses are throwing our certainties]. / Quand certains flavivirus remettent en cause nos certitudes.

During the past two decades, a number of mosquito-borne flaviviruses, mainly of African origin, have invaded new geographical areas where they have never been active. This was the case for the Japanese encephalitis virus which reached the northeastern part of Australia (1995) and, above all, for the West Nile virus which, since 1999, entirely colonized the American continent. Then, the Usutu virus invaded a large part of the Western Europe (2001) while the Zika virus caused a large epidemic in an island of Micronesia (2007). Finally, in 2010, the Tembusu virus devastated many duck farms in China while the Bagaza virus, after having provoked human encephalitis in India, reached the southern part of Spain. In the affected areas, new pathogenic outcomes were observed in humans and animals while new vertebrate hosts and mosquito species were infected. Moreover, unusual ways of contamination were described. The origins of this unprecedented evolution remain to be clarified.

[Asymptomatic infections in man: a Trojan horse for the introduction and spread of mosquito-borne arboviruses in non-endemic areas?]. / Infections inapparentes chez l'Homme : un cheval de Troie pour l'introduction et la diffusion des arbovirus transmis par des moustiques dans les régions non endémiques ?

In mosquito-borne arbovirus infections in man the asymptomatic cases are much more frequent than the symptomatic ones, but their true role in the introduction and subsequent spread of such diseases in non-endemic areas remains to be clarified. We have collected pertinent data from English and French literature from 1952 to 2010 through Pubmed and other bibliographic sources. Data were analysed to assess if viremia in asymptomatic human arbovirus infections might be sufficient to represent a true risk for introduction in non-endemic areas. During dengue and chikungunya fever outbreaks, humans are believed to be the only vertebrate hosts. Since a very large number of individuals are infected and since viremic levels are known to vary by many orders of magnitude in symptomatic patients, it is reasonable to augur that a proportion of asymptomatic cases might reach levels of viremia sufficient to infect competent mosquitoes. Moreover, in both dengue and chikungunya fever, nosocomial infections have been identified representing an alternative opportunity for virus introduction in non-endemic areas. In zoonotic mosquito-borne arbovirus infections such as Japanese encephalitis or West Nile infection, the situation is quite different since humans are considered as "dead-end" hosts. However, the very large number of asymptomatic cases arising during outbreaks and the existence of newly recognised ways of contamination (blood transfusion, organ transplantation, transplacental way etc.) may also ensure their introduction and subsequent spread in new areas.

[Human monkeypox]. / Le monkeypox humain.

Unlike other recent viral emergences, which were in majority caused by RNA viruses, the monkeypox results from infection by a DNA virus, an orthopoxvirus closely related to both vaccine and smallpox viruses and whose two genomic variants are known. Unexpectedly isolated from captive Asiatic monkeys and first considered as an laboratory curiosity, this virus was recognised in 1970 as an human pathogen in tropical Africa. Here it was responsible for sporadic cases following intrusions (for hunting) into tropical rain forests or rare outbreak with human-to-human transmission as observed in 1996 in Democratic Republic of Congo. As monkeypox in humans is not distinguishable from smallpox (a disease globally eradicated in 1977) it was only subjected to vigilant epidemiological surveillance and not considered as a potential threat outside Africa. This point of view radically changed in 2003 when monkeypox was introduced in the USA by African wild rodents and spread to 11 different states of this country. Responsible for 82 infections in American children and adults, this outbreak led to realize the sanitary hazards resulting from international trade of exotic animals and scientific investigations increasing extensively our knowledge of this zoonosis.

[Mosquito-borne arboviruses and pregnancy: pathological consequences for the mother and infant. A general review]. / Grossesse et arbovirus transmis par des moustiques: conséquences pathologiques pour la mère et l'enfant. Une revue générale.

Vertical transmission of arboviruses, mainly those transmitted by mosquitoes, was considered for a long time as an exceptional event in pregnant women. However, during the recent years, as a result of the global upsurge of these viral infections, several surveys and reports clearly demonstrated that the resulting pathologies were increasing in both severity and frequency in endemic countries where pregnant women are at risk. In order to better assess such new epidemiological trends, the authors performed a general review as exhaustive as possible of the pathological consequences of the infection during pregnancy caused by the four dengue viruses and Japanese encephalitis, West Nile and Chikungunya viruses. At the therapeutic and preventive levels we are quite unarmed in the face of such severe accidents as their pathogenesis remains presently unclear

[Assessing epidemiological consequences two years after the tsunami of 26 December 2004?]. / Le tsunami du 26 décembre 2004: quel bilan épidémiologique deux ans plus tard?

In December 2004, a very devastating tsunami struck the coasts of a number of countries along the Indian Ocean inducing about 280,000 deaths and at least 125,000 injured persons. As after such disaster the occurrence of large epidemics of cholera, malaria or arbovirus infections are to be expected. In fact, two years later, no outbreak has been reported among the exposed populations and this is probably the usual outcome for such disasters. However an real increase in number of cases of melioidosis and many bacterial or fungic infections affecting the pulmonary tract, the skin and the injured soft tissues, was noted mainly in repatriated tourists. These latter infections were due to rare or atypical, frequently multiresistant, microorganisms.

[Emergence of new viruses in Asia: is climate change involved?]. / Emergence de virus nouveaux en Asie: les changements climatiques sont-ils en cause?

Tropical Africa is not the only area where deadly viruses have recently emerged. In South-East Asia severe epidemics of dengue hemorrhagic fever started in 1954 and flu pandemics have originated from China such as the Asian flu (H2N2) in 1957, the Hong-Kong flu (H3N2) in 1968, and the Russian flu (H1N1) in 1977. However, it is especially during the last ten years that very dangerous viruses for mankind have repeatedly developed in Asia, with the occurrence of Alkhurma hemorrhagic fever in Saudi Arabia (1995), avian flu (H5N1) in Hong-Kong (1997), Nipah virus encephalitis in Malaysia (1998,) and, above all, the SARS pandemic fever from Southern China (2002). The evolution of these viral diseases was probably not directly affected by climate change. In fact, their emergential success may be better explained by the development of large industry poultry flocks increasing the risks of epizootics, dietary habits, economic and demographic constraints, and negligence in the surveillance and reporting of the first cases.

[Bacterial and viral epidemics of zoonotic origin; the role of hunting and cutting up wild animals]. / Epidémies bactériennes et virales d'origine zoonotique. Rôle de la chasse et du dépeçage d'animaux sauvages.

Since the Prehistoric times hunting has been a vital activity for man. However, this may account for the contamination of the hunter, his family and relatives. Infections may occur by direct contact with blood or tissues of infected animal during handling and cutting up preys and when preparing or eating meat, or also when bitten by injured animal. Apes and antelopes hunting in sub-Saharan Africa proves to be particularly important since it has been well established that the recent or previous emergence of some viral zoonosis (Ebola, Aids, T lymphotropic viruses and Monkeypox) resulted from hunting and poaching. Moreover predation among different species of non human primates such as that practised by chimpanzees against monkeys, has led to the construction of recombinant simian Lentiviruses, such as SIV cpz able to infect man and then spread over the entire mankind as it was the case with HIV-1. SARS is another possible example of the zoonotic risks represented by the sale, handling and cutting up Chinese wild animals such as Himalayan civets for culinary purposes.

Detection of Israel turkey meningo-encephalitis virus from mosquito (Diptera: Culicidae) and Culicoides (Diptera: Ceratopogonidae) species and its survival in Culex pipiens and Phlebotomus papatasi (Diptera: Phlebotomidae).

Israel turkey meningo-encephalitis (ITME) virus was detected in pools of Ochlerotatus caspius Pallas and Culicoides imicola Kieffer trapped at a turkey run at Nir David during an outbreak in August 1995. Experimental membrane feeding on a blood ITME suspension showed that Culex pipiens L. became harbored virus for at least 14 d. When Phlebotomus papatasi Scopoli were fed on an infected turkey, they became infected and harbored the virus for at least 7 d. Because Phlebotomines are trapped frequently at turkey runs in Israel, they should be suspected as potential vectors of ITME.

[Centenary of the discovery of yellow fever virus and its transmission by a mosquito (Cuba 1900-1901)]. / Le centenaire de la découverte du virus de la fièvre jaune et de sa transmission par un moustique (Cuba 1900-1901).

During the 17th, 18th and 19th centuries, yellow fever has been an ordinary scourge in American cities. In the early part of the 20th century, a main discovery has been achieved in Havana city, Cuba, leading to direct consequences for tropical medicine, public health and virology. There, the U.S. Army yellow fever commission headed by Walter Reed proved that yellow fever was a viral disease transmitted by a specific mosquito, Stegomyia fasciata, in fact Aedes aegypti L. The idea that vomito negro would be spread by mosquito bites was not a new one. It has already been postulated, since 1881, by Carlos Finlay, a Cuban physician, who has attempted to prove experimentally his hypothesis in human beings, but without real success. The U.S. Army commission quickly demonstrated two essential facts ignored by C. Finlay, which explained his failure. To be able to transmit yellow fever, Ae. aegypti had to bite a patient during the first three days of the disease (viraemia), and then, a delay of about 12 days was necessary before the mosquito would be ready to transmit the disease to a non immune human (the virus replication time inside the insect). Since the role of mosquito in spreading yellow fever was established, an efficient means to fight the scourge was available, i.e., the mosquito extermination. This concept was quickly applied leading to the complete clean up of Cuba (1901) and the Panama isthmus (1907).

[Tick-borne diseases and changes in the ecosystem in Lorraine]. / Maladies vectorielles à tiques et modifications de l'écosystème en Lorraine.

The number of persons suffering from tick-borne diseases has notably increased in the French region of Lorraine since the mid 1990s. Greater awareness of the pathology is insufficient to explain such an increase in incidence. Instead, the proliferation of ticks is a major factor in the increased incidence of cases, and is mainly due to a modification of the ecosystem. Prophylaxis is based upon appropriate information for persons concerned and requires a sound understanding of the biology and habits of the vector ticks. Numerous factors--anthropogenic, natural, social--may contribute to the destabilisation of a well-balanced ecosystem, but all are more or less the direct result of human activity. The geographic specificities of this region may be an additional factor in the emergence of tick-borne diseases.