JMM Profiles

Journal of Medical Microbiology is now publishing ‘JMM Profiles’ in one of three categories; Pathogen Profile, Antimicrobial Profile and Diagnostic Profile. These articles will provide a brief summary review in each of these areas. The profiles are fully citable and free to read for 30 days after publication, and will make an excellent resource for education or reference.
Collection Contents
1 - 20 of 26 results
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JMM Profile: Sindbis virus, a cause of febrile illness and arthralgia
More LessSindbis virus (SINV) is the causative agent of a febrile infection commonly called Ockelbo disease, Pogosta disease or Karelian fever in northern Europe. Finland, Sweden, Russia and South Africa experience periodic SINV outbreaks. SINV is classified within the family Togaviridae and genus Alphavirus. Symptoms of SINV infection in humans include joint inflammation and pain, fever, rash and fatigue. In some cases, joint symptoms can persist for years after recovery from the initial infection. Clinical signs of SINV infection are rarely reported in animals, although infection in horses has been documented. There is no specific treatment or vaccination. The virus is transmitted by mosquitoes, particularly those belonging to the Culex genus, but Aedes, Culiseta or Mansonia species may also act as vectors. Wild birds act as amplifying hosts and are implicated in the long-distance spread of the virus.
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JMM Profile: Salmonella enterica serovar Gallinarum, biovars Pullorum and Gallinarum
More LessSalmonella serovar Gallinarum has two distinct biovars, Pullorum and Gallinarum. They are host-adapted avian pathogens that infect a number of wild and domesticated species but they pose a particular threat to farmed and backyard chickens and turkeys. Both biovars cause invasive and septicaemic disease, often resulting in high mortality. Pullorum is transmitted in eggs and typically affects birds soon after hatch. Gallinarum may cause disease in any age of bird, which often progresses through mature flocks. The establishment of clean breeding stock has resulted in freedom from the pathogens in many countries although even in these territories sporadic incursions still occur.
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JMM Profile: Usutu virus
More LessUsutu virus (USUV) is an emerging arbovirus belonging to the family Flaviviridae, genus Flavivirus. It is maintained in an enzootic cycle, with mosquitos as the vector and birds as the main amplifying host. Humans, and other mammals such as horses, are dead-end hosts. The virus was originally detected in sub-Saharan Africa, but in the past two decades has spread across Europe. In certain bird species, such as the Eurasian blackbird (Turdus merula), USUV is extremely virulent and can be fatal. Human infection is rare and often asymptomatic, but multiple short-term neurological diseases have been reported, highlighting its public-health risk.
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JMM Profile: Swine influenza A virus: a neglected virus with pandemic potential
Swine influenza is an acute respiratory disease of swine caused by swine influenza A virus (SwIAV). The ability of SwIAV to spread bidirectionally from animals to humans (zoonotic), and from humans to animals (reverse zoonotic), drives coinfection that can result in gene segment exchange and elevates the risk of generating viruses with pandemic potential. Compared to human-origin influenza A viruses, current data indicate a greater diversity amongst circulating SwIAVs, with three major subtypes (classified by haemagglutinin and neuraminidase) circulating globally in swine (H1N1, H1N2 and H3N2). The lack of protection afforded by human seasonal influenza vaccines against SwIAVs exacerbates the risk associated with reassortment of human, swine and potentially avian viruses. As such, global monitoring of SwIAVs is important for both human and animal health as they represent a true ‘One Health’ challenge with pandemic potential.
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JMM Profile: Bartonella bacilliformis: a forgotten killer
More LessBartonella bacilliformis causes Carrión’s disease, an infectious disease present in rural Andean areas of Peru and Ecuador. The disease has an acute and a chronic phase called Oroya fever and Peruvian wart, respectively. Oroya fever is potentially fatal if treated inadequately. Female Lutzomyia verrucarum, a phlebotomine sand fly endemic to South America, is the major vector. B. bacilliformis exhibits high susceptibility levels to a variety of antibacterial agents. B. bacilliformis is difficult to culture. Most endemic areas are remote with fragile health systems and poor communication. Thus, the true burden of the disease is difficult to ascertain.
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JMM Profile: Japanese encephalitis virus: an emerging threat
More LessJapanese encephalitis (JE) is an infection that occurs predominantly in Asia and the Pacific Islands. It is transmitted by mosquito bites, with the main vector being Culex tritaeniorhynchus, and is maintained in enzootic cycles involving pigs, wild birds and mosquitoes. JE is caused by infection with Japanese encephalitis virus (JEV), a zoonotic pathogen that also causes disease in mammals such as pigs and horses. In humans, most symptoms are mild or flu-like but can progress to encephalitis. Pigs are considered amplification hosts, and sows may have gestational complications. Horses may exhibit neurological signs. Detection of the virus can be confirmed by serological or molecular laboratory tests. Vaccination offers protection against JEV infection in humans, pigs and horses. Whilst there is no effective treatment of JE, human cases may require hospitalization for supportive therapy, which may include administration of fluids, oxygen and medication to treat symptoms.
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JMM Profile: Trichosporon yeasts: from superficial pathogen to threat for haematological-neutropenic patients
More LessTrichosporon yeasts are classical agents of superficial mycoses, and they are ranked as the first to second predominant basidiomycetous yeast able to cause invasive infections. The clinical presentation of Trichosporon infections varies with the affected anatomical site, with fungaemia present in the majority of invasive trichosporonosis cases. Only a limited number of antifungal compounds can be used to treat Trichosporon infections. Azoles are the first choice due to their intrinsic resistance to echinocandins. Better laboratory methods and up-to-date databases of commercial platforms are required to improve identification, susceptibility testing and surveillance of this potentially threating infection.
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JMM Profile: Rift Valley fever: a zoonotic viral haemorrhagic disease
More LessRift Valley fever (RVF) is caused by infection with Rift Valley fever virus (RVFV), a mosquito-borne RNA virus that affects both humans and livestock species. Humans can also acquire infection from contact with infected animals and contaminated bodily fluid. Veterinary vaccines are available for use in livestock, but no vaccines have been approved for humans to date. The virus is currently endemic in most sub-Saharan regions of Africa but numerous incursions into Middle Eastern countries and islands in the Indian Ocean, such as Mayotte (an overseas Department of France), have occurred in the past decade. The risk of further geographical expansion is high and therefore additional investigation is warranted to better understand disease transmission and pathogenic mechanisms to develop threat mitigation strategies.
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JMM Profile: Staphylococcus epidermidis
More LessStaphylococcus epidermidis is the most abundant commensal bacterium of human skin. Despite protecting us from foreign invaders, S. epidermidis itself exploits human vulnerability when given the opportunity. Such opportunities arise when patients are immunocompromised or when biomedical implants present an opportunity to colonize the surface and form biofilms. S. epidermidis is one of the most frequently isolated organisms from implanted devices and from bloodstream infections. However, S. epidermidis infections are often recalcitrant to antibiotics because of biofilm-associated antibiotic tolerance. Furthermore, the emergence and spread of nearly pan-resistant strains is a considerable health concern. Symptoms can be subclinical, making diagnosis challenging, and treatment with antibiotics is inefficient. For now, infection prevention remains the best strategy available.
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JMM Profile: Brachyspira species: the causative agent of Avian Intestinal Spirochaetosis
More LessThe genus Brachyspira includes nine officially recognised species, several of which are pathogenic to mammals and birds. B. pilosicoli, B. intermedia, and B. alvinipulli are the causative agents of avian intestinal spirochaetosis (AIS), a gastrointestinal disease in poultry caused by the colonisation of the caeca and/ or colo-rectum by Brachyspira . AIS primarily affects layer hens and broiler breeders over the age of 15 weeks. The severity of symptoms can vary but typically presents as reduced growth rates, delayed onset of lay, reduced egg production, faecally stained eggs, and diarrhoea. This disease is estimated to cost the UK laying industry £18 million per annum. Brachyspira colonisation in humans is common in populations from developing countries and HIV-positive patients; however, it is rarely investigated as a human pathogen.
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JMM Profile: Avian paramyxovirus type-1 and Newcastle disease: a highly infectious vaccine-preventable viral disease of poultry with low zoonotic potential
Newcastle disease (ND) is a highly contagious disease of poultry caused by virulent avian paramyxovirus-1 (APMV-1) (previously termed avian avulavirus-1 and avian orthoavulavirus-1). APMV-1 is endemic in poultry in many developing countries, whilst outbreaks still occur in developed countries, affecting both commercial and backyard flocks. ND outbreaks can have substantial economic consequences due to high mortality rates and the imposition of trade restrictions. APMV-1 nucleic acid can be detected from swabs or tissues of suspected cases by PCR. Evidence of infection or vaccination may be demonstrated by the presence of specific antibodies against HN in serum samples. No anti-viral treatments exist, but vaccines are available, although there are currently concerns over their efficacy.
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JMM Profile: Fosfomycin: a potential antibiotic for multi- and extensively resistant bacteria
More LessFosfomycin (FOF) is the first antimicrobial of the epoxide class. It is commercially available in oral and parenteral formulations. Oral FOF is widely used to treat uncomplicated cystitis in women, while parenteral FOF is extensively utilized for upper urinary tract infections. FOF has a broad-spectrum bactericidal activity with a low risk of cross-resistance to other antimicrobial classes. Therefore, parenteral FOF is increasingly prescribed adjunctive therapy to treat extra-urinary tract infections caused by multidrug-resistant, Gram-negative bacteria.
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JMM profile: rifampicin: a broad-spectrum antibiotic
More LessRifampicin (also known as rifampin) inhibits RNA synthesis, and is used to treat tuberculosis, leprosy, staphylococcal infections and legionnaires’ disease. It can also protect at-risk populations from Haemophilus influenzae type b and Neisseria meningitidis . It is a polyketide antibiotic and is on the World Health Organization (WHO) list of essential medicines due to its critical importance to human medicine. The adverse effect of liver toxicity is controlled by testing during prolonged treatment regimes. Rifampicin’s red–orange colour can result in the colouration of sweat, tears and urine. Resistance to rifampicin arises from mutation of the target RNA polymerase or ADP ribosylation of the antibiotic or efflux. Mycobacteria may become singularly resistant to rifampicin or as part of multidrug or extensive drug resistance.
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JMM Profile: Achromobacter xylosoxidans: the cloak-and-dagger opportunist
More LessAchromobacter xylosoxidans is associated with resilient nosocomial infections, with bacteraemia, pneumonia and chronic cystic fibrosis lung infection being the most common clinical presentations. Innate multi-drug resistance and a suite of virulence factors select for A. xylosoxidans infection during long-term antibiotic therapy, contributing to its persistence, treatment recalcitrance, association with poor clinical outcomes and emergence as a problematic pathogen. Horizontal gene transfer and maintenance of large genomes underpin the resilience and cosmopolitan lifestyle of A. xylosoxidans , and complicate its phylogenetic characterization.
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JMM Profile: Avian influenza: a veterinary pathogen with zoonotic potential
Avian influenza viruses (AIVs) are classified as either low pathogenicity (LP; generally causing sub-clinical to mild infections) or high pathogenicity (HP; capable of causing significant mortality events in birds). To date, HPAIVs appear o be restricted to the haemagglutinin (HA) glycoprotein H5 and H7 AIV subtypes. Both LPAIV and HPAIV H5 and H7 AIV subtypes are classified as the causative agents of notifiable disease in poultry. A broad range of non-H5/non-H7 LPAIVs also exist that have been associated with more severe disease outcomes in avian species. As a result, the constant threat from AIVs causes significant economic damage in poultry production systems worldwide. The close proximity between mammalian and susceptible avian species in some environments provides the opportunity for both inter-host transmission and mammalian adaptation, potentially resulting in novel AIV strains capable of infecting humans.
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JMM Profile: Louping ill virus
More LessLouping ill virus (LIV) is a single-stranded, positive-sense RNA virus within the genus Flavivirus that is transmitted to vertebrate hosts by bites from infected ticks, the arthropod vector. The virus affects livestock in upland areas of Great Britain and Ireland, resulting in a febrile illness that can progress to fatal encephalitis. Prevention of the disease is facilitated by combining acaricide treatment, land management and vaccination strategies. However, vaccines have been discontinued in recent years. Although rare, LIV can be transmitted to and cause disease in humans. Consequently, LIV infection is a threat to human and veterinary health and can impact on the rural economy.
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JMM Profile: Tick-borne encephalitis virus
More LessTick-borne encephalitis (TBE) is caused by a neurotropic flavivirus, transmitted by the bite of Ixodes species tick vectors, and is increasing in incidence and expanding its geographical range throughout Eurasia and the Far East. Most infections are asymptomatic. However, between 2 and 30 % of cases may develop into severe neurological disease, long-term neurological sequelae or death. Diagnosis is based upon clinical signs of neurological disease and demonstration of virus-specific IgM and IgG antibodies. There is no specific antiviral treatment and supportive care is required for the various manifestations of disease. Vaccination is an effective way of preventing disease.
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JMM profile: Loop-mediated isothermal amplification (LAMP): for the rapid detection of nucleic acid targets in resource-limited settings
More LessLoop-mediated isothermal amplification (LAMP) is a rapid alternative to PCR, in which the reaction occurs at one temperature and uses a polymerase with high displacement activity, e.g. Bacillus stearothermophilus DNA polymerase I (Bst) or homologues. Since the discovery of LAMP in 2000, several applications have been developed to employ this technique in the rapid detection of nucleic acid targets and enhance its performance. Improvements to the LAMP technique and a variety of innovative detection methods have led to its application for a wide range of targets in medical and veterinary microbiology, particularly in resource-poor settings. The key advantages of LAMP-based diagnostics include the ability to rapidly detect target nucleic acid sequences within 30 min and its ease of use, facilitating its application in field, bedside, pen-side, point-of-care and point-of-need diagnostic settings. LAMP can be a valuable tool to aid in the detection and management of disease outbreaks.
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JMM Profile: Actinobacillus pleuropneumoniae: a major cause of lung disease in pigs but difficult to control and eradicate
More LessThe Gram-negative bacterium Actinobacillus pleuropneumoniae is the causative agent of pleuropneumonia in pigs, its only known natural host. Typical symptoms of peracute disease include fever, apathy and anorexia, and time from infection to death may only be 6 h. Severe lung lesions result from presence of one or two of the ApxI-III toxins. Control is through good husbandry practice, vaccines and antibiotic use. Culture and presence of the species-specific apxIV gene by PCR confirms diagnosis, and identification of serovar, of which 19 are known, informs on appropriate vaccine use and epidemiology.
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