Monthly Archives: May 2011

European Microbiology Congress

European Microbiology Congress

This year the European Society for Clinical Microbiology and Infectious Diseases joined forces with the International Congress of Chemotherapy to hold a combined European microbiology congress in Milan. The combined resources of both organisations resulted in a busy four-day programme that attracted a huge turnout from across Europe and beyond. The critical mass of specialists is a big drawcard for anyone who wants to keep up with recent developments in clinical microbiology and infectious diseases. Unlike some of the larger northern hemishpere meetings, ECCMID brings together clinical and laboratory elements of our discipline, partly explaining the strong attendance from Australasia and the Western Pacific.

Amoeba: root of all evil? The stand-out plenary lecture was Didier Raoult’s talk on amoeba as a progenitor of infection which went far beyond the Legionella/Acanthamoeba collaboration, to expound ideas of divergent phylogenic origins of microbial lifestyles. Big picture stuff delivered with panache, for which a hot link and a few lines in a blog is a very poor substitute. Raoult has a story worth following in detail.

MALDI-TOF. For the clinical laboratory, PCR-based assays had to play second fiddle for a change. The hot item was bacterial proteome analysis by matrix assisted laser desorbed ionisation-time of flight mass spectrophotometry (MALDI-TOF analysis) which is being used by an ever-widening laboratory pool to rapid bacterial identification. Comparisons of the two main equipment platforms are tackling practical clinical lab tasks, as major centres work out where this game-changing technology fits in the overall scheme of things. Large data libraries are already available on which to base identification of unknown bacterial isolates. As with all novel techniques, weakness are starting to turn up, some of them specific to one or other equipment platform. These include identification of some enteric Gram negative bacteria including Salmonella, Shigella and E.coli. Other bacteria that pose difficulties include Strep. pneumoniae and anaerobic bacteria. Interestingly, the method appears to work poorly on CSF, possibly because it is not an amplification technique, like PCR.

Multiresistant Gram negative bacteria. The gathering storm of MDR Gram negatives featured in a series of workshops, symposia and other sessions. Prominent bacterial species causing problems of a multi, extra and pan-resistant nature are Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumanii. Resistance mechanisms of particular concern were carbapenemases, AmpC betalactamases, and extended spectrum betalactamases but efflux pumps, porin change and the role of mobile genetic elements in dissemination of multi-resistance also gained a dishonorable mention. While molecular manipulation of antibiotics to enhance resistance to these resistance mechanisms, and non-antibiotic agents are being tried to enhance susceptibility, the immediate outlook appears grim.

Food & water microbiology. The working party of food & water related infections hosted a training workshop on infections associated with recreational waters which made the Micrognome even more nervous about stepping barefoot onto the beach. A more detailed report will be provided on the potential risk of distributing multiresistant enteric bacteria via drinking water and food. These topics were covered by a series of speakers in a surprisingly well-attended symposium on the last day of the ECCMID congress, reflecting growing concern in Europe over where this issue may be headed.

Milan, the venue for this year’s ECCMID, is perhaps best known for its contribution to fashion and less for culture, cuisine or fine art. Running concurrently with the congress was an exhibition of works by Arcimboldo; a Renaissance artist renowned for his grotesque portraits composed of items from the natural world.  His lesser known work included some of the most delicately observed illustration of natural history imaginable, long before the explosion of interest in taxonomy that occured during the 19th century. The Micrognome wonders what Arcimboldo might have made if he had had a microscope to assist his observations of readily ab=vailable flora and fauna.

Pseudomonas folliculitis

Pseudomonas folliculitis

Notes from a talk given at the European Congress of Clinical Microbiology & Infectious Diseases, 2011. Pseudomonas aeruginosa is a versatile environmental bacterial species that breeds in the nooks and crannies of spa and whirlpool baths. The skin infections it can cause are probably under-recognised, but where public health surveillance is in place, have appeared in small case clusters. Some states have active monitoring of spa bath hygiene measures.

Sources:

  1. Hopkins, R.S. et al. Follicular dermatitis outbreak caused by Pseudomonas aeruginosa associated with a motel’s indoor swimming pool. Pub Health Reports 1981; 96: 246-9.
  2. Vogt, R. et al. Pseudomonas aeruginnosa skin infections in persons using whirlpool in Vermont. J Clin Microbiol 1982; 15: 571-4.
  3. Surveillance for water-borne disease outbreaks – United States, 1995-6. MMWR, 1998; 47 (SS-5), 1-34.
  4. Pseudomonas dermatitis/folliculitis associated with pools and hot tubs – Colorado and Maine, 1999-2000. MMWR, 2000; 49: 1087-91.
  5. Mena, K.D. & Gerba, C.P. Risk assessment of Pseudomonas aeruginosa in water. Rev Environ Contam Toxicol 2009; 201: 71-115.
  6. Hengge, U.R., Bardell, V. Green nails. Images in Clinical Medicine, NEJM, 2009; 360: 11.

Pseudomonas folliculitis

Slow food safety

Safe with slow food?

The MicroGnome has been asking “is is safe” since an unpleasant encounter with an unidentified food-borne pathogen overseas at the end of 2010. The subsequent enteric fever episode put our favorite gnome out of action for a whole weekend, but it took weeks to restore him to rude good health.

Not that long ago the MicroGnome fell foul of another food-borne pest. This time he caught it red-handed and was able to name the culprit as Salmonella Typhimurium. Once again he suffered a febrile episode, rigors and sweating episodes, followed by measurable weight loss. Try as he might, the MicroGnome failed to implicate the faulty foodstuff, but he has a shrew idea what it might have been.

Throughout the year our toll of food borne infection is a disgrace. We really have to ask ourselves if we can’t do a bit better than this in sourcing, preparing, cooking, serving storing or distributing foods. Surely a developed country can get its food act together and avoid the majority of foodborne disease?

It is fascinating how the Slow Food movement has caught on in a part of the world where good food is a matter of national pride. It is perhaps a little surprising that the likely food hygiene advantage of sourcing ingredients locally, sticking with what’s in season and aiming for the freshest food available has not been trumpeted more. Perhaps it’s because in Piedmont, the home of the Slow Food movement, outbreaks of foodborne infection are unheard of. A quick scout through on-line sources failed to find any reports of slow food-associated infection, but you’d be right in pointing out that an absence of evidence is not quite the same as evidence for absence.

This has to be an issue for debate: motion – Slow Food in the strict sense of the term reduces the risk of foodborne infection. Let’s hear from the movement, and from the fast, convenient food industry. We need hard data to inform our opinions. And if the Slow Food movement is right, they may need reclassification as a public health intervention.

MicroGnome, May 2011.