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The Ebola disease derives its name after a small river, the Ebola River, flowing through the former Zaire (present day DR Congo) and was formally named in 1976. The disease belongs to the category of diseases referred to as “haemorrhagic fever”; the causal agent – a filovirus (from Latin “filo” = thread) belonging to the Filoviridae family. The treatment of Ebola has been only symptomatic, i.e. based on mitigation of the symptoms related to the infection, such as kidneys and liver. An effective vaccine has not been developed yet, even though rigorous attempts have been made and reported. Ebola has been primarily found in the Ivory Coast, DR Congo, Sudan, Gabon and other equatorial African countries. Based on the data obtained during the latest epidemics, people are strongly advised to avoid direct contact with patients, avoid buying bush meat in street markets and not handle dead bats, megabats, monkeys or gorillas. Estimated data suggest that more than 5,000 of these animals have died. The disease was also diagnosed in patients in the USA and Europe. The epidemic afflicted West Africa and had significant implication on their economy in terms of lost production, higher fiscal deficits, rising prices and lower real household incomes, leading to greater poverty.

Especially in the temperate zone, female bats are exposed to increased energy demands during gestation. In addition, abiotic factors, such as ambient temperature and pathogen load, can significantly affect reproduction success. Bats are considered natural reservoirs for a wide variety of pathogenic agents, and have developed strong immune systems to cope. Nevertheless, very little is known about the influence of these pathogenic microorganisms on bat health as most infections are asymptomatic. In this study, we monitored presence of non-tuberculous mycobacteria (NTM) in female common noctule bats Nyctalus noctula during gestation. Eight NTM species, subspecies or complexes (Risk Group 1: Mycobacterium hiberniae and M. terrae complex; Risk Group 2: M. arupense, M. avium ssp. hominissuis, M. fortuitum, M. interjectum, M. peregrinum, M. septicum) were confirmed as part of the female gut microbiome during gestation, with representation changing during foetal development. Following hibernation, most females were infected, though infection load and severity were relatively low. Just prior to parturition, however, a high proportion of females were infected with a high, often pathogenic, NTM load. Females who gave birth to twins had a higher (though non-significant) proportion of positive samples after hibernation and before parturition. Negative correlations between two consecutive measurements suggest that female N. noctula can cope with NTM loading, even during energy-demanding pregnancies. Bat faeces appear to be a source of numerous NTM species and, as such, bats can be considered as vectors for NTM spread in the environment. [ABSTRACT FROM AUTHOR]

Human hepatitis E is endemic worldwide, particularly in Asia, where large waterborne outbreaks have been reported (1). Seroprevalence of hepatitis E virus (HEV) is >60% in rural southern People's Republic [...]

Studies are being conducted to determine whether live Mycobacterium avium subspecies paratuberculosis are entering the milk supply in the Czech Republic both in general retail pasteurized milk and in locally pasteurized milk from three specific dairy herds. The results show that humans are being exposed to this chronic enteric pathogen by this route despite the milk being pasteurized to the national and European Union's standards.

Research has been conducted on the microbial enzymes, haloalkane dehalogenase. The cloning, sequencing and expression of the dhmA haloalkane dehalogenase gene from Mycobacterium avium subsp. avium N85 have been carried out and the results of DhmA biochemical characterization from crude extracts are reported.

Researchers describe 14 of the 18 copies of IS900 insertions in the genome of Mycobacterium avium subsp. paratuberculosis. The DNA flanking the insertions was analyzed and homologues were found in Mycobacterium tuberculosis and Mycobacterium avium subsp. avium.

Hepatitis E virus (HEV) is a leading cause of epidemics and sporadic cases of enterically transmitted hepatitis worldwide. The zoonotic potential of HEV was recognized recently, and pigs and other [...]

To the Editor: Tuberculosis is a chronic wasting disease in domestic birds (especially hens) and free-ranging birds worldwide (1). Most mycobacterial infections in birds are caused by Mycobacterium avium subsp. [...]

Abstract Background Different approaches are used for determining the number of Mycobacterium avium subsp. paratuberculosis (MAP) cells in a suspension. The majority of them are based upon culture (determination of CFU) or visual/instrumental direct counting of MAP cells. In this study, we have compared the culture method with a previously published F57 based quantitative real-time PCR (F57qPCR) method, to determine their relative abilities to count the number of three different MAP isolates in suspensions with the same optical densities (OD). McFarland turbidity standards were also compared with F57qPCR and culture, due to its frequent inclusion and use in MAP studies. Findings The numbers of MAP in two-fold serial dilutions of isolates with respective OD measurements were determined by F57qPCR and culture. It was found that culture provided lower MAP CFU counts by approximately two log10, compared to F57qPCR. The McFarland standards (as defined for E. coli) showed an almost perfect fit with the enumeration of MAP performed by F57qPCR. Conclusions It is recommended to use culture and/or qPCR estimations of MAP numbers in experiments where all subsequent counts are performed using the same method. It is certainly not recommended the use of culture as the standard for qPCR experiments and vice versa.

The presence of Mycobacterium avium subsp. paratuberculosis in retail cheeses from Greece and the Czech Republic is investigated. Consumption of these cheeses is likely to result in human exposure to Mycobacterium avium subsp. paratuberculosis, albeit at a low level for viable cells, as 31.7% and 3.6% of the samples reacted positive by PCR and culture, respectively.

Abstract Background Mycobacterium avium subspecies paratuberculosis (Map) causes an infectious chronic enteritis (paratuberculosis or Johne's disease) principally of ruminants. The epidemiology of Map is poorly understood, particularly with respect to the role of wildlife reservoirs and the controversial issue of zoonotic potential (Crohn's disease). Genotypic discrimination of Map isolates is pivotal to descriptive epidemiology and resolving these issues. This study was undertaken to determine the genetic diversity of Map, enhance our understanding of the host range and distribution and assess the potential for interspecies transmission. Results 164 Map isolates from seven European countries representing 19 different host species were genotyped by standardized IS900 - restriction fragment length polymorphism (IS900-RFLP), pulsed-field gel electrophoresis (PFGE), amplified fragment length polymorphisms (AFLP) and mycobacterial interspersed repeat unit-variable number tandem repeat (MIRU-VNTR) analyses. Six PstI and 17 BstEII IS900-RFLP, 31 multiplex [SnaBI-SpeI] PFGE profiles and 23 MIRU-VNTR profiles were detected. AFLP gave insufficient discrimination of isolates for meaningful genetic analysis. Point estimates for Simpson's index of diversity calculated for the individual typing techniques were in the range of 0.636 to 0.664 but a combination of all three methods increased the discriminating power to 0.879, sufficient for investigating transmission dynamics. Two predominant strain types were detected across Europe with all three typing techniques. Evidence for interspecies transmission between wildlife and domestic ruminants on the same property was demonstrated in four cases, between wildlife species on the same property in two cases and between different species of domestic livestock on one property. Conclusion The results of this study showed that it is necessary to use multiple genotyping techniques targeting different sources of genetic variation to obtain the level of discrimination necessary to investigate transmission dynamics and trace the source of Map infections. Furthermore, the combination of genotyping techniques may depend on the geographical location of the population to be tested. Identical genotypes were obtained from Map isolated from different host species co-habiting on the same property strongly suggesting that interspecies transmission occurs. Interspecies transmission of Map between wildlife species and domestic livestock on the same property provides further evidence to support a role for wildlife reservoirs of infection.

The cloning of the haloalkane dehalogenase genes dmbA and dmbB from Mycobacterium bovis 5033/66 is described and the dehalogenase activity of their translation products is demonstrated. The melting temperature assessed by circular dichroism spectroscopy of DmbA is 47 degree Celsius and DmbB is 57 degree Celsius.

To the Editor: Mycobacterium avium subsp. hominissuis infection is often detected in pigs and humans (1-3). In most cases, the main sources of this agent are environmental (4,5). During the [...]