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C Chastel

Publications and source records attributed to C Chastel.

At least 19 recordsLinked to original sources
PubMed2004

[Bacterial and viral epidemics of zoonotic origin; the role of hunting and cutting up wild animals].

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.

Acquired Immunodeficiency Syndrome↗
PubMed2004

[Emergence of new viruses in Asia: is climate change involved?].

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.

Africa↗
PubMed2003

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.

Animals↗
PubMed2003

[Centenary of the discovery of yellow fever virus and its transmission by a mosquito (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).

Aedes↗
PubMed2002

[Tick-borne diseases and changes in the ecosystem in 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.

Adaptation, Physiological↗
PubMed1999

Chizé virus, a new phlebovirus isolated in France from Ixodes (Trichotoixodes) frontalis.

A new phlebovirus (Bunyaviridae family, Phlebovirus genus), provisionally designed Chizé virus, was isolated from a nymph of Ixodes (Trichotoixodes) frontalis collected on a wren (Troglodytes troglodytes) found dead in the Chizé forest, western France. Chizé virus produced a lethal encephalitis in one-day-old mice and cytopathic effect (CPE) in Vero cells. Extracellular particles with a mean diameter of 105 nm with surface spikes characteristic of Uukuniemi (UUK) serogroup viruses were observed in Vero cells. Chizé virus reacted in complement-fixation test with several UUK serogroup viruses but was readily distinguished from all registered viruses in the serogroup. I. frontalis is highly specific for birds and unlikely to transmit Chizé virus to humans or domestic animals; the pathogenicity of the new virus to wild birds remains to be clarified.

Animals↗
PubMed1999

[Viruses and civilization].

A few million years ago, when primates moved from the east African forest to the savannah, they were already infected with endogenous viruses and occultly transmitted them to the prime Homo species. However it was much later with the building of the first large cities in Mesopotamia that interhuman viral transmission began in earnest. Spreading was further enhanced with the organization of the Egyptian, Greek, Roman, and Arab empires around the Mediterranean. Discovery of the New World in 1492 led to an unprecedented clash of civilizations and the destruction of pre-Columbian Indian civilizations. It also led to a rapid spread of viruses across the Atlantic Ocean with the emergence of yellow fever and appearance of smallpox and measles throughout the world. However the greatest opportunities for worldwide viral development have been created by our present, modern civilization. This fact is illustrated by epidemic outbreaks of human immunodeficiency virus, Venezuela hemorrhagic fever, Rift valley fever virus, and monkey pox virus. Close analysis underscores the major role of human intervention in producing these events.

Civilization↗
PubMed1999

[Paul-Louis Simond and the Marchoux mission in Brazil].

In 1900 the role of a particular mosquito called Stegomyia fasciata in the transmission of yellow fever was proved by a board of American medical officers. This discovery was the beginning of several scientific missions in South America, mostly in Brazil. As yellow fever was increasing in its West African colonies, the French government decided to send a scientific mission to Rio de Janeiro, to find new ways of prevention against the disease. Under the authority of the Institut Pasteur, Paul-Louis Simond, who had just discovered the role of the flea in the transmission of plague, was designated to carry through this mission together with Emile Marchoux and Alexandre Salimbeni, eminent Pasteurians like him. From November 1901 to May 1905, the three men studied the epidemiological and clinical aspects of the disease in Rio. They worked on the intermediate host's entomology, the Stegomyia female mosquito, improving the knowledge of yellow fever and its means of transmission. They also realized experiments on 25 healthy volunteers, submitting them to the bite of infected mosquitoes. They were among the first to proceed to yellow féver vaccinations by means of virulent serum heated to 55 degrees C or filtered. Their work led to the establishment of new sanitary rules to prevent the spread of the disease. This contributed to the success of the "yellow fever campaign" initiated by Oswaldo Cruz in the town of Rio. One of the most original contribution of their studies was to show that the yellow fever agent (which was still unknown) could be transmitted from an infected female Stegomyia to its eggs and larvaes. After this mission, the French authorities were able to fight yellow fever efficiently in their African colonies as well as in the West Indies and French Guyana.

Animals↗
PubMed1999

[The "plague" of Barcelona. Yellow fever epidemic of 1821].

The outbreak of yellow fever that struck Barcelona in 1821 followed a typical pattern for the times: a brick from Cuba introduced the disease in the port docks; the epidemic first reached the poor suburbs, and finally the center of the city. It was assumed that at least 20,000 inhabitants died from the scourge, that is a sixth of the total population of the city estimated 120,000. French authorities promptly took emergency measures at land and maritime borders by locking French ports to Catalan vessels and defining a quarantine line along the Pyrenean border controlled by an army 15,000 strong. French medical team including six physicians and two nuns was sent to Barcelona to provide assistance. Long after the epidemic had receded, the Pyrenean quarantine line was maintained by the French authorities for a hidden political purpose: Paris wished to contain Spanish Liberalism, a "revolutionary pest". French troops engaged in the so-called quarantine line were used in 1823 for invading the Spanish kingdom, while French physicians returning to Paris were celebrated as heroes and benefactors of the mankind although they had not provided any serious contribution to the therapeutics or the epidemiology of yellow fever. They were glorified in publications of the time without reserve. This unexpected manifestation of nationalism was welcomed and encouraged by the government of Louis XVIII who felt himself threatened by the liberal opposition.

Altruism↗
PubMed1998

Revised group classification of the genus Spiroplasma.

Significant changes have been made in the systematics of the genus Spiroplasma (class Mollicutes) since it was expanded by revision in 1987 to include 23 groups and eight sub-groups. Since that time, two additional spiroplasmas have been assigned group numbers and species names. More recently, specific epithets have been assigned to nine previously designated groups and three sub-groups. Also, taxonomic descriptions and species names have been published for six previously ungrouped spiroplasmas. These six new organisms are: Spiroplasma alleghenense (strain PLHS-1T) (group XXVI), Spiroplasma lineolae (strain TALS-2T) (group XXVII), Spiroplasma platyhelix (strain PALS-1T) (group XXVIII), Spiroplasma montanense (strain HYOS-1T) (group XXXI), Spiroplasma helicoides (strain TABS-2T) (group XXXII) and Spiroplasma tabanidicola (strain TAUS-1T) (group XXXIII). Also, group XVII, which became vacant when strain DF-1T (Spiroplasma chrysopicola) was transferred to group VIII, has been filled with strain Tab 4c. The discovery of these strains reflects continuing primary search in insect reservoirs, particularly horse flies and deer files (Diptera: Tabanidae). In the current revision, new group designations for 10 spiroplasma strains, including six recently named organisms, are proposed. Three unnamed but newly grouped spiroplasmas are strain TIUS-1 (group XXIX; ATCC 51751) from a typhiid wasp (Hymenoptera: Tiphiidae), strain BIUS-1 (group XXX; ATCC 51750) from floral surfaces of the tickseed sunflower (Bidens sp.) and strain BARC 1901 (group XXXIV; ATCC 700283). Strain BARC 2649 (ATCC 700284) from Tabanus lineola has been proposed as a new sub-group of group VIII. Strains TIUS-1 and BIUS-1 have unusual morphologies, appearing as helices at only certain stages in culture. In this revision, potentially important intergroup serological relationships observed between strain DW-1 (group II) from a neotropical Drosophila species and certain sub-group representatives of group I spiroplasmas are also reported.

Animals↗