Feline chronic lymphocytic plasmacytic stomatitis/gingivitis

Feline chronic lymphocytic plasmacytic gingivitis and stomatitis (FGS) is a painful condition for the cat and a distressing condition for both the cat's carer and for the veterinary surgeon because of its intractability. Feline calicivirus can be isolated from almost 100% of cases, but is not the sole cause of the problem. The incidence of feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV) in chronic gingivostomatitis is no greater than in the general population, although many papers have linked the condition with these viruses. The condition may also be partially caused by highly processed cat food - particularly dry cat food. Some cats presenting with aggressive behavioural problems may, in fact, be suffering from this condition. This webpage is written for veterinary surgeons, to address the lack of easily available information, but an ebook is available for cat guardians.

I am very keen to find a cure for this condition.  If you are a veterinary surgeon and would like to take part in an email discussion group, please email draddie@btinternet.com and put "FGS email group" in the subject. 



Ebook for guardians - My Cat Has Feline Chronic Gingivostomatitis - What Now?

Ebook for veterinarians: Feline Infectious Upper Respiratory Disease and Chronic Gingivostomatitis

Cause of FGS

Clinical signs




Case study


Further reading and references

FGS support group forum


Ebook "My Cat Has Feline Chronic Gingivostomatitis - What Now?" written for cat guardians.

The chapters are:

1. What is feline chronic gingivostomatitis?
2. What causes feline chronic gingivostomatitis?
3. How is feline chronic gingivostomatitis treated?
4. What you can do to help your cat recover from feline chronic gingivostomatitis.
5. If your cat dies.

6. Feline chronic gingivostomatitis and the cat breeder.
7. Feline chronic gingivostomatitis and the cat rescuer.
8. Glossary of weird and technical terms.
9. What you can do in the fight against feline chronic gingivostomatitis.
10. Useful websites.
11. Information factsheet to take to your veterinary surgeon.

You can buy this ebook instantly by downloading the free sample copy (but you can only pay in US dollars). If you buy using the buttons below, there will be a delay of up to 24 hours until you will be manually sent a download link, so please be patient. Please note that the download is an .exe file, so you may have to disable your computer's security programme or firewall.


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Upper respiratory disease in cats e-books

Download an e-book on feline infectious upper respiratory disease and feline chronic lymphocytic plasmacytic gingivostomatitis (note this e-book is only for undergraduate and postgraduate veterinary surgeons, especially those studying for feline or small animal medicine certificates or for continuing professional development. The e-book is not worded for non-veterinarians). In addition to everything contained on this webpage, the e-book contains tables of differential diagnoses, a section about infectious respiratory disease control in catteries, details about feline vaccination and treatment, the truth about azithromycin, notes on less common upper respiratory infections of the cat and more extensive lists of references and websites for further reading.

Purchase feline upper respiratory infection and FGS e-book

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The exact aetiology of feline chronic lymphocytic plasmacytic gingivostomatitis (FGS) is unknown and likely to be multifactorial.  However, it is probably caused by combination of feline calicivirus (FCV) infection and the cat's inappropriate immune reaction within the stomatitis lesions (shift from normal Th type 1 response (cellular) to a mixed Th type 1 and 2 (humoral) response.
(Harley et al, 1999). Feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) have both been linked with the condition, but in my last two small studies, the incidence of these viruses was no more than in the general cat population in the UK.  Bartonella henselae infection has also been implicated, but its involvement is controversial, with two recent studies ( Quimby et al 2008; Belgard et al 2010) showing no association.

In humans, chronic gingivostomatitis can be due to intolerance to food ingredients (e.g cinammon) or additives, especially those of chewing gum or the fizzy Scottish drink, Irn Bru. Just before Lucky, the cat described in the case report below, dramatically improved, his food had been changed to the additive-free Classic Cat Food. I believe that the food change aided his recovery and have since then seen recovery of a second cat after a change of food to Wild Kitty Cat Food. In addition, Applaws food, available in the UK, is highly palatable, made of good natural ingredients, and is helping some cats with FGS - it is especially useful in cats who are anorexic. Modern processed diets with high omega 6:3 ratios are associated with chronic inflammatory diseases in the human (Simopoulos, 2008) and could well be linked to the same in the cat - diets rich in polyunsaturated fats lead to higher levels of circulating pro-inflammatory cytokines (Ferrucci et al, 2006). Cat foods that use soy and other non-meat or fish products to boost protein content are likely to be causing a detrimental, pro-inflammatory, omega 6:3 ratio in cats, therefore cats suffering from FGS should be changed to a more natural diet, whilst being aware of the risk of hypervitaminosis A should fish be given for too long.

Clinical signs

Cats with chronic gingivostomatitis can present with difficulty in eating, salivation, gagging, pawing at the mouth and possibly be presented as behavioural cases - having become grumpy or even aggressive (due to the pain). Examination of the mouth reveals inflammation around the teeth, or where the teeth used to be, and also the palatoglossal folds (fauces). Take care to differentiate this condition from juvenile feline periodontitis and from gingivitis/periodontitis due to dental disease - the latter will be cured simply by extraction of rotten teeth and cleaning of the others.


Definitive diagnosis of  feline chronic lymphocytic plasmacytic gingivostomatitis is by biopsy and biopsy is useful to differentiate FCGS from similar appearing conditions, such as tumour or eosinophilic granuloma.

Diagnosis of feline calicivirus can be performed with an oropharyngeal swab.  Virus isolation is still the diagnostic test of choice for this virus because of genetic variability of the virus (so some reverse-transcriptase polymerase chain reaction (RT-PCR) tests will give false negative results).  However, virus isolation is not available in all countries. A negative test for FCV does not rule out a diagnosis of feline chronic gingivostomatitis.

Recommended laboratories:

This list is unfortunately nowhere near complete and I apologise if your country is missed. Scandinavian countries usually send their samples to Veterinary Diagnostic Services in Scotland, UK.

France - Scanelis laboratory, which is attached to the Ecole Nationale Veterinaire Toulouse - for quantitative RT-polymerase chain reaction to detect FCV.

UK - Veterinary Diagnostic Services, University of Glasgow Veterinary School - who perform virus isolation. Telephone them on 0141 330 5777 or email Companion, to order viral transport media, swabs and sample submission forms. You may also wish to send a biopsy of the lesion in 10% formol saline.

USA - In America, the feline calicivirus RT-qPCR test which I would recommend you use is available from the Lucy Whittier Molecular and Diagnostic Core Facility. You can download a sample submission form from the website.


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The treatment with the highest reported success rate for this condition remains complete removal of all teeth and especially the roots by a specialised veterinary dentist. A good veterinary dentist can achieve cure rates as high as 80%. However, this procedure is not without risk: Smith et al (2003) report penetration of the eyeball in 3 cats and 2 dogs following dentistry, with subsequent loss of the eye. And of course general anaesthetics always carry a risk too. Not surprisingly, many owners would prefer to try conservative treatment first.

Conservative treatment is aimed at using a non-allergenic food, restoring normal mouth flora (healthy cat's mouths have predominantly Pasteurella multocida, 50% of cats with stomatitis have spirochaetes), trying to eliminate FCV, and shifting the immune response back to type 1. For the latter, it is not a good idea to use corticosteroids, but a non-steroidal anti-inflammatory safe for use in the cat (e.g. Metacam). Thalidomide is ideal, since it is safe, anti-inflammatory, and shifts the immune response from mixed Th1 and Th2 back to a healthy Th1. Cimetidine is being recognised to stimulate the Th1 response, and may be worth trying, it certainly shouldn't do any harm.  To my knowledge, it has not yet been used to treat this condition.

Corticosteroids are absolutely contraindicated because of the high rate of diabetes mellitus development following long term therapy, the risk of obesity and because whilst they appear to help the cat initially, there is a bounce-back effect - with the cat re-presenting with worse clinical signs than initially and requiring higher and higher doses just to maintain. Corticosteroids suppress both humoral and cell-mediated immunity, reducing the cat's chance of clearing the infection, and causing thinning of the epithelium.

The treatment I currently recommend is as follows: Metacam (continually, or until complete healing), Antirobe for 6 weeks (or on alternative weeks - week on, week off), Applaws, Almo Nature, or Classic cat food (continually or until complete healing), 1MU Virbagen Omega per kg every other day subcutaneously for 5 injections, thereafter monitor clinical progress and give injections as required. Individual cats require differing regimes of Virbagen Omega injections - some every other day, others only once a week, others recover completely and no longer require injections. Submucosal injections of Virbagen Omega are reported to give good results. See below for more details.

Download information factsheet for veterinary surgeons (an at-a-glance summary of treatments I recommend) in a new window. Continue on for more detailed information.






Slippery elm in honey

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Antirobe (clindamycin) 5mg/kg bid for 6 weeks or Convenia (Pfizer) by injection every 2 weeks for 1-2 doses

NOT Metronidazole 4-6 weeks (metronidazole has a suppressant effect on cell mediated immunity in mice, and may be less desirable in this condition where CMI is preferable to the humoral response).


Feline interferon: Virbac make feline recombinant interferon (Virbagen Omega). Note that feline interferon omega should always be stored in the fridge and will remain viable once reconstituted for up to 21 days at 4oC.

Subgingival use: A dose of 1 million units (0.2ml of a 5 million unit vial, 0.1ml of a 10 million unit vial) locally into the junction between healthy gum and diseased gum given when the cat is anaesthetised has been reported to have excellent results (Camy 2004, Mihaljevic 2004, Southerden 2006). However, some cats require more than one treatment and if they are poor anaesthetic risks an alternative may be preferable.

Case study by Dr Guy Camy

Subcutaneous injections: 1 MU/kg, or 0.1 ml/kg of the reconstituted solution, once every other day for 5 treatments. Thereafter attempt to reduce dosage to twice a week, provided the cat is still doing well. Discontinue treatment only after three attempts to isolate calicivirus have been negative (these can be at weekly intervals). We find monitoring the cat's weight a useful objective way of assessing response to treatment.

Suppliers: NVS, Abbeyvet

Virbagen Omega website

Case studies of Virbagen Omega


Human interferons: - (feline interferon is preferable if available) - Intron A (human recombinant interferon) obtained as 3M I.U. from local pharmacist (write a prescription). Dilute in one litre of saline, aliquot into 1ml volumes, freeze for up to a year. Defrost as required, dilute 1:100 to get 30 I.U. per millilitre, keep refrigerated for up to a week. Treat continually, until FCV shedding ceases.

Dose: 30 I.U. per day orally



Corticosteroids should be AVOIDED because although the cat may improve initially, ultimately the condition will worsen or become more chronic. For preference, use non-steroidal anti-inflammatories.

Meloxicam (Metacam, Boehringer Ingelheim) is preferable to steroids in the control of this condition. In our study, both controls and the IFN omega group were put onto Metacam.

Day 1: 0.3mg/kg sid with food
Days 2-7: 0.1mg/kg sid with food

Thereafter reduce the dose until you find the minimum that keeps the cat comfortable: most cats will maintain on 1-2 drops per cat per day.



Try Alan Pharmaceuticals in the UK or Freedom-Pharmacy.com to source thalidomide. If you cannot source it, put your cases onto Metacam.

Thalidomide is a good anti-inflammatory to use in this condition but can be difficult to obtain. If you do manage to get it, remember to explain to the owner that thalidomide is not licensed for the cat and remember that it is absolutely contrindicated in an entire female cat.

Dose: 1-2 x 50 mg capsules per day given in the evening

NOT to be used in pregnant queens



1mg/kg sid per os for 5 days


10-25 mg/kg every 48 hours

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Food is a very important feature in this condition, I don't know why. Possible reasons include:

  • sensitive/allergy type reaction to some components of highly processed foods
  • micronutrient deficiency
  • wrong omega 3:6 ratio causing a pro-inflammatory state in the cat being fed too much grain-based food

Below is a video I made about food in FGS. (Veterinarians, it counts for 13 minutes continuing professional development.)


Some affected cats improve on Applaws food (available from Pets at Home and called Encore from Sainsburys), Almo Nature, or Classic Cat Food (a tinned and pouch food made by Butcher's, available in Safeway, Pets at Home and other supermarkets and British pet food shops) and metacam alone. Lucky, the cat in the case study reported below, had just been changed to Classic Cat Food prior to his recovery. (For local suppliers of Classic food or for buying in bulk, phone Butchers on 01788 823711.) A diet of Wild Kitty Cat Food (an American cat food) cured one cat in about 6 weeks. I currently recommend a change to any of these foods for cats suffering from this condition. It is essential to give cats as much variety in their diet as possible - many of the big pet food companies have brainwashed vets into telling their clients to only give their particular make of food to their pets - this is crazy advice. Suppose a food lacks a vital micronutrient? Suppose it has a contaminant? Eating that food and no other will maximise the dose the cat eats.The safest option long-term is as much variety in the diet as possible, even though in the short term (i.e. a couple of months), while trying to figure out what a cat may be sensitive to, a limited diet is needed.

I am often asked what can people use in countries which do not have Classic food, or for cats who do not like Classic.

ApplawsApplaws natural cat food is a delicious cat food which is useful for cats whose mouth is so sore that it has affected their appetite. In addition, one recovered cat who occasionally drools (salivates excessively) stops doing so on being given chicken Applaws (but not tuna flavour). MPM have recently introduced a dry food which has been safely given to my own stomatitis recovered cat without causing recrudescence of clinical signs. This is a unique dried food in having a protein carbohydrate ratio around 80:20 (the opposite of other dry cat foods and more closely approximating the natural prey of cats). However, whatever food you give, it is vital not to feed only one food but to give plenty of variety in the diet.

Phone Roger Coleman on 08707 508 606 for a sample or order from the website: mpm products.

Another food to consider is Almo Nature - I have given the dry food to a recovered FGS case for some months now without inducing recurrence of the condition.

I would be keen to hear from any veterinarians who have experience of using these, or other, foods to control feline chronic gingivostomatitis.

Dr Lisa Pierson's website has good advice for making your own cat food:


McIntyre and Tuck (2000) reported improvement of cats on a multiple micronutrient and enzyme supplement called PetPlus.



Antioxidants such as vitamins A, C and E and zinc improve mucous membrane health and possibly have anti-viral and/or immune stimulant activities. One has to be careful of using vitamin A in the cat for 2 reasons: first the cat can't absorb or convert well the beta-carotene forms (i.e. those found in plant foods), so it must be given in the form of liver or fish oil (halibut or cod), secondly, vitamin A SHOULD NOT be used for more than 6 weeks or there is a risk of hypervitaminosis A and bone deposition. Also be aware that long term use of vitamin C in the cat can predispose to oxalate crystalluria.

vitamin A: 200-400 i.u./kg/day for less than 6 weeks
vitamin C: 125mg/cat bid
vitamin E: 25-75 i.u./cat/bid
zinc: 7-10mg/cat/sid

Slippery elm in honey

UK vet, David Leicester, reports some response to slippery elm in honey applied directly to the lesions. This herb is used widely by humans with inflammatory bowel disease and has been shown to have antioxidant effects on mucosae in vitro.

Dave writes the following:

"The product I have been using is:

"Phytoplex Slippery Elm" produced by: Animal Alternatives, PO Box 289, Richmond, Surrey, TW10 7HX, England, UK. I must stress that I have no association whatsoever with this company and am not on a commision (though perhaps I should be!! ;-))

Each tablet contains: 400.0mg Slippery Elm Bark; 0.001ml Cinnamon Oil BP; 0.001ml Clove Oil BP; 0.001ml Peppermint Oil BP.

This formulation is actually sold as a digestive remedy for a plethora of GIT problems in dogs and cats.

The recommended dose for GIT indications for cats is 1/2 tablet TID

The manufacturers claim no contraindications and the further research I have done appears to support this.

For the topical treatment of oral inflammation and ulcers I have been grinding up a single tablet and mixing with c5ml of honey. This pasty mixture is then syringe directly onto the affected areas at regular intervals throughout the day. It is very well tolerated and as I reported previously seems to work wonders in a very short period of time. I postulate that at least part of the response is due to the local anaesthetic effect of the oil components and possibly also the antiseptic effects of the honey, I'd be interested to hear if anyone has any thoughts on this matter.

I have seen 2 cats in the last 3 years develop diabetes mellitus from the chronic use of long acting steroid preparations for this problem and will not use them unless it's going to be euthanased otherwise. I have always tried to get them onto tablets in the past to allow alternate day therapy but with limited success. I am now using a combination of occasional steroid +/- antibiotic courses (usu Antirobe- clindamycin but sometimes Stomorgyl- metronidazole/spiramycin), xrays/dental and root extractions, lysine for viral related cases, chlorhexidine mouth washes and slippery elm in honey. If anyone is still trying to find Slippery Elm then try health food shops or over the internet, or you could always give Animal Alternatives a call as that's where I get mine. There must be plenty of other companies making it though as its widely recommended in human herbalist books for gut problems."

Dave's email is: derby@vets-now.com
Telephone: (UK) 0208 940 3725


After recovery - feeding and vaccination

Feeding - the same advice applies to the recovered cat as to the cat with FGS - see above.

Vaccination - previously, my advice was not to vaccinate (or give vaccine boosters to) a FGS recovered cat against feline calicivirus (one of the cat flu viruses) in case vaccination caused recrudescence of clinical signs. However, I was recently forced to vaccinate a cat who had recovered from chronic gingivostomatitis and used Merial's Purevax RCP - the cat remained well.


List of specialist veterinary dentists with experience of this condition


South Africa






Dr. Susann-Yvonne Mihaljevic
Eywiesenstr. 4
D-88212 Ravensburg

Tel.: 0751 363140
Fax.: 0751 3631414
E-Mail: mail@tierklinik-rv.de


South Africa

Dr Johann Kotze
Roodekruin Veterinary Clinic
South Africa
Tel: (011) 764 6262
Email: johann.vet@gmail.com


Albert Lloret
Service of internal medicine
Hospital Clinic Veterinari (Vet Teaching Hospital)
Universitat Autonoma de Barcelona
Barcelona, Spain
tel +34935811894
fax +34935813428



efevet [at] gmail.com


The British Veterinary Dental Association will help you find one of their members to refer a case to.


1.Cecilia Gorrel  runs a dental clinic at Cedar Vet Group
81 Victoria Road
BH22 9HU

Phone: personal assistant, Sue, on 02380 891900
Phone: 01202 861622
Fax:      01202 861622


2. Alex J Smithson
Veterinary Dental, Oral & Maxillofacial Referrals
07887 650812
NW England

Clinics at-
PetMedics, Worsley, Manchester 0161 794 4999

(ask for Hazel, 16.00-22.00)

Manchester Street Veterinary Surgery, Oldham, Lancs 0161 624 4596
Chestergate Referrals, Cheshire, 01244853823


3. Pete Southerden
Eastcott Veterinary Clinic
6, Clive Parade
Cricklade Rd

4. Gerhard Putter  BVSc  MRCVS
Mulberry Court Veterinary Surgery
171-173 Melford Road
CO10 1JU

Tel: 01787  881888
Fax:01787  880689
E mail: gerhard@mulberryvets.co.uk
Web Site: www.mulberryvets.co.uk





None listed yet.


Case study

Feb 2000.

Lucky is a MN DSH. He was referred to Dr Diane Addie by his veterinary surgeon, Mr Gerry Henry, who had extracted most of his teeth (the treatment of choice for this condition). Mr Henry had also treated Lucky with extensive broad spectrum antibiotics and on referral, Lucky had only a sparse culture of Moraxella. Lucky was negative for FeLV and FIV, but feline calicivirus (FCV) was isolated. Treatment was begun with 50 mg thalidomide sid and 200 mg lactoferrin powder (kindly donated by Ko Shiino, Morinaga Foods, Germany) applied directly to the lesions daily.

Sep 2000 Lucky has now improved considerably. He has stopped shedding FCV. He has been changed to Butcher's Classic Cat Food, which I believe to be highly significant.

May 2001. Lucky is 100% recovered and is still FCV negative. Dec 2002 - Lucky still has a healthy mouth!

Reference - Addie et al, 2003.

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While a cat has clinical signs of chronic gingivostomatitis, I do not recommend that he be vaccinated. After recovery, I used to recommend that the cat would not be vaccinated with a vaccine containing feline calicivirus (FCV), for fear that vaccination would cause return of clinical signs. However, when my own cat, Tommy, recovered I had to vaccinate him, because he had never been vaccinated and therefore was at risk from feline panleukopenia virus (feline parvovirus). Eliminating all vaccines which contained live FCV, I chose Purevax RCP by Merial to vaccinate him with. Happily he was absolutely fine - he has received his first course of two injections 3 weeks apart and a 3rd injection a year later and his mouth remains fine.




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Further information and references

The Born Free Foundation has a wonderful exposé of the cat food industry:

Dr Lisa Pierson has good advice for making your own cat food:

Price-Pottenger Nutrition Foundation

Addie D.D., Radford A., Yam P.S., Taylor D.J. 2003 Cessation of feline calicivirus shedding coincided with resolution of clinical signs in a case of chronic gingivostomatitis. Journal of Small Animal Practice 44 (4) 172-176

Belgard S, Truyen U, Thibault JC, Sauter-Louis C, Hartmann K. 2010 Relevance of feline calicivirus, feline immunodeficiency virus, feline leukemia virus, feline herpesvirus and Bartonella henselae in cats with chronic gingivostomatitis. Berl Munch Tierarztl Wochenschr.  123(9-10):369-76.

Camy G. 2004 A clinical case of feline chronic gingivitis-stomatitis. Veterinary Interferon Handbook. Ed. Karine de Mari. Virbac 94-99

Dolieslager SM, Riggio MP, Lennon A, Lappin DF, Johnston N, Taylor D, Bennett D.  2011  Identification of bacteria associated with feline chronic gingivostomatitis using culture-dependent and culture-independent methods.  Vet Microbiol.  24;148(1):93-8.

Endo H, Rees TD. 2007 Cinnamon products as a possible etiologic factor in orofacial granulomatosis.   Med Oral Patol Oral Cir Bucal.  12(6):E440-4.

Ferrucci L, Cherubini A, Bandinelli S, Bartali B, Corsi A, Lauretani F, Martin A, Andres-Lacueva C, Senin U, Guralnik JM.  2006  Relationship of plasma polyunsaturated fatty acids to circulating inflammatory markers.  J Clin Endocrinol Metab.  91(2):439-46.

Harley R, Helps CR, Harbour DA, Gruffydd-Jones TJ, Day MJ. 1999 Cytokine mRNA expression in lesions in cats with chronic gingivostomatitis. Clinical and Diagnostic Laboratory Immunology. 6 4 471-478

Mihaljevic S. 2004 Management of a clinical case of severe gingivo-stomatitis in a cat and its treatment based on feline omega interferon. Veterinary Interferon Handbook. Ed. Karine de Mari. Virbac 100-103

McIntyre Penman S, Tuck M, 2000  A pilot study to explore the effects of active enzymes on the oral health of cats and dogs.  BVDAJ.  7

Quimby JM, Elston T, Hawley J, Brewer M, Miller A, Lappin MR. 2008 Evaluation of the association of Bartonella species, feline herpesvirus 1, feline calicivirus, feline leukemia virus and feline immunodeficiency virus with chronic feline gingivostomatitis. J Feline Med Surg. 2008 10(1):66-72.

Simopoulos AP. 2008 The importance of the omega-6/omega-3 fatty acid ratio in cardiovascular disease and other chronic diseases.  Exp Biol Med (Maywood). 233(6):674-88.

Smith MM, Smith EM, La Croix N, Mould J. Orbital penetration associated with tooth extraction. J Vet Dent. 2003 20(1):8-17.

Southerden P, Gorrel C. Treatment of a case of refractory feline chronic gingivostomatitis with feline recombinant interferon omega.  J Small Anim Pract. 2007  48(2):104-6.

Theyse LFH, Logan EI, Picavet P. 2003. Partial extraction in cats with gingivitis-stomatitis-pharyngitis complex - beneficial effects of a recovery food. Proceedings Hill's European Symposium on Oral Care. Amsterdam 2003 64-65

Veterinary Clinics of North America. Feline Dentistry


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4 July 2012

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