Ticks and tick-borne diseases in Belgium: recent updates

Dr. Ir. Valérie Obsomer

Europe= 65000 cases detected per year (Hubalek el al. 2009) but 22000 in NL?Incidence is largely underestimated

Introduction: incidence in Europe?

HighMediumLowNegligibleNul

MethodologyDefine a level of incidence per level of risk

Use % of territory covered per risk level, to propose an estimate

5501253050

Incidence per 100000

Risk of being bitten by ticks

Erythema Migrant monitored in Austria, Belgium and the Netherlands

Reliable data

Number: estimates of annual cases

Other vector ticks

Number of cases per year: 1 175 825Incidence per year: 201/100000Number of seropositive: 39 029 579 (7% of European population)

Risk level (estimated incidence)(Quartiles)

Low (0-37/100000)Medium (38-120/100000)High (121-315/100000)Very high (316-605/100000)No info

In Belgium?

Preliminary results from the public survey on bites and symptoms

1500 first answers: general statistics www.tekentiques.net

Knowledge updates

Demonstration of seriousness of the situation in our country

Ideas for solutions

Objectives

Analysis and recording of existing data about

1. Ticks in Belgium en Belgique ( > 80000 ticks recorded on 1624 sites)

2. Pathogens

3. Incidence of tick-borne diseases

http://www.parasitesandvectors.com/content/6/1/190

Information source:

Table of contents

2. Pathogens

1. Ticks

4. Human cases

3. Human vector contact

5. Symptoms and diagnosis

6. Conclusion

1. 1 Ticks: which species?

>14 species in Belgium2 have an impact on human health: known vectors, infected, bite humans, frequent on cats and dogs, everywhere in Belgium

The other species contribute to circulating pathogens in the wildlife

I. ricinusThe most frequent on animals and humanQuest for host on the vegetation

More than 90 microorganism found in that speciesParasite most vertebrates: increase circulating pathogens between species

I. hexagonusPresent in nest or burrowPresent in urban gardens – surface nest are a risk for gardening

1.2. I. ricinus distribution

Rare? Only local?

Pffocial report EFSA EU : 2010

Public Health- Belgium

Any region

Locally very abundant

Recording of existing data (Obsomer et al, 2013)

Imperfect recording

1.3. More ticksThere is an increase in the number of ticks I. ricinus in nature

Why an increase? Nothing certain

Climate warmingLand cover changeMore efficient tick subspeciesIncrease in cervid and wildboar populationDisequilibrium in species- predator-hostsInvasive species: ticks or hosts

64% more ticks in 2013 in the Netherlands (tekentradar)

Ticks have been present for years in the country but at low abondance

Increase in Belgium identified by nature professionnals and the population

Public survey: started around 1990, or only in 2013 in other regions

The risk of being bitten depend from abundance

Documented abroadMore and more locations present abondant population of ticks

If this increase is recorded in 2013 in some region: is this just happening now?

www.tekentiques.net

Table of contents

2. Pathogens

1. Ticks

4. Human cases

3. Human vector contact

5. Symptoms and diagnosis

6. Conclusion

Introduction – Tiques – Pathogènes – Transmission/contact – Maladies – Conclusions 7/34

2. PathogenPathogens found in Belgium – Public health: no systematic study

Pathogens found in our species abroad – potentially present in Belgium

95 micro-organisms found in I. ricinus of which at least 45 are pathogenic

Borrelia myanmotoi found at the border in France and the Netherlands

Lyme, anaplasmose and rickettsies pathogenic for human are found all over Belgium in ticks collected on cats and dogs or the vegetation

Babesiosis more locally around Rochefort (Claerebout et al, 2013)

6 or 7 Borrelia species found in Belgium (Heylen et al, 2013)

To improve

Classical molecular technique to seach for pathogens in ticks (QPCR) will find only what is looked for

New techniques exist (NGS) which analyse all DNA that is found in ticks and search to which pathogens it could belong: more systematic

2.1 Pathogens – distribution and diversity

(Claerebout et al, 2013)

2.2. Abondance of Borrelia b s.l. – agent of Lyme disease

2.3. Diversity of Borrelia b s.l. – agent of Lyme disease

Toutes les borrélies pathogènes sont présentes dans les tiques trouvées sur les mésanges

2.4. Pathogens are all around us in natureTicks

Ixodes ricinus bites all vertebrates and make pathogens circulate between species11 out of 14 tick species carry Borrelia

30% of bird specific ticks are infected by BorreliaBird

Other animals that carry Borrelia in Belgium ( and ticks)Rabbit, squirrels, dog, horse, hedgehogs, blackbirds, Great tit,

Bétail30% of Walloon cows are seropositive for BorreliaL’anaplasmose causes abortus in cows in the Flanders

Babesia causes mortality in calves around Rochefort towards the German border

The lizard seems to reduce Borrelia presence in ticks Some species influence presence of ticks and borrelia

Rabbits seem to reduce tick populationAnts, chicken and birds seem to eat ticksLarge mammals feed hundreds of adult ticks ready to lay eggs ( cervids, wild boar)

Table of contents

2. Pathogens

1. Ticks

4. Human cases

3. Human vector contact

5. Symptoms and diagnosis

6. Conclusion

Very small – 6 legs

Engorged adult ticks ( which alread have fed) are easy to see. Because people see such large ticks on their dogs or cats, they do not think that tick and particularly nymphs are so small and don’t look proerly for tick bites on their body

• Have many pathogens• taken on the first host (rodent, bird, cervid, ...)

Eat once on a host then fall off and change into adultsHost 2

•Eat once on a host, then fall off and change into nymph

• Infected only by pathogens received from the adult female: 4% borrelia (25% for Hexagonus), Babésia

Host 1

• Carry even more pathogens Host 3

Quite easy to see on human

Les nymphes sont petites

eggs

Ixodes ricinus: life cycle

The most dangereous because hard to see and very infected!

3. Transmission and contact

Number of bites since birth: 1 to 750 times including 100 times/year (forest workers) 41% have been bitten 5 times or more, 31% 10 times or more and 28% once

Ticks might bite everywhere on the body but particularly hot places. 38% of tick bites are located in areas difficult to check: hair, rear neck, back, between the buttocks, on the genitals, the belly button, the back of the knee.

37% of people ( out of 112 answers) do not know that ticks can wander around on the body before biting – they check only exposed parts

32% of the people are bitten in their garden or at school

5.6% of transmission route identified (1264 answers) are attributed to other than ticks including other undetermined insect (26 cases), deer flies (14 cases), from mother to child (12 cases), mosquitoes (5), flea (4), other (4), chiggers (aoutat) (2), blood transfusion (2), spider (1), sexual transmission (1)

Transmission by deer fly in Belgium is documented in the literature as well as transmission from mother to child in utero

Results from the survey:

Table of contents

2. Pathogens

1. Ticks

4. Human cases

3. Human vector contact

5. Symptoms and diagnosis

6. Conclusion

4. Human cases in Belgium

Example year 2010

INAMI Total tests : 229250

INAMI Number of persons ( because IgG/igM) tested First Line Test: 129000 INAMI

Erythema migrans: 90 per 100000 *population*63% Lyme with EM = 15000 cases

Vigie laboratory: 1116 cases

Reference laboratory positive lab tests: 500 cases

Introduction – Tiques – Pathogènes – Transmission/contact – Maladies – Conclusions 21/34

Borrelia

7.4% of people positive for Borrelia also have anaplasma (Guillaume et al, 2002)

15% of patients negative for Borrelia and who have symptoms are positive for anaplasma (Heyman et al, 2003)

Anaplasma

Only 300 tests for anaplasma required – while it is very abondant in ticks

Only 10 tests for rickettsia required – while it is very abondant in ticksNo recorded tests for Human Babesia

Other

4.1. Borrelia in the Netherlands: 22000 cases/ year

ticks = Bites = Erythèmes

- Association have alerted the government- A web site record tick bites and now also erythema migrans (www.tekenradar.nl)- Regular monitoring of the number of Erythema migrans and tick bites: a

questionnaire every 4 years sent to 8000 general practitionners- A dedicated service at the governmental level on vector borne diseases

Introduction – Tiques – Pathogènes – Transmission/contact – Maladies – Conclusions 18/34

Prevention measure: take rapidly ticks off the skin: NOT ENOUGH TO STOP THE INCREASE IN THE NUMBER OF CASES

(Public Health Institute NL - Sprong et al. 2013)

New research: treat all the tickbite by 1 day antibiotic

4.2. Official numbers in BelgiumInadequate monitoring = no data

Introduction – Tiques – Pathogènes – Transmission/contact – Maladies – Conclusions 19/34

Most cases are not accounted for

Number of cases per year: 500 or 1500 cases according to ISP, not the same distribution

?

Labo vigiesReference labs

Only positive second line tests (western blot) for some voluntary laboratoriesVery few doctors require a second test if the first test is positive ( elisa)Many people are still tested at the EM stages – which gives false positive

The tests cannot detect all the Belgian Lyme species ( 2 to 5 according to the lab)

1994

2009

200920052001

2009 20092009

0 to 25 per 10000025 to 50 per 10000050 to 100 per 100000100 to 200 per 100000>200 per 100000 20092004

2005 2009

Introduction – Tiques – Pathogènes – Transmission/contact – Diseases – Conclusions 20/34

Erythema migrants survey, questionnaire sent to 161 medical doctors: 15000 cases

From 2004 to 2009: 8% increase in 4 years

2005 ( Hofhuis) 2009 ( Hofhuis)

2006 ( INAMI) 2009 ( INAMI)

ELISA Blood test IgGELISA Blood test IgG

Erythema migrans from GP Network ( 8000 GPs)

Erythema migrans from GP Network ( 8000 GPs)

Introduction – Tiques – Pathogènes – Transmission/contact – Maladies – Conclusions 22/34

Table of contents

2. Pathogens

1. Ticks

4. Human cases

3. Human vector contact

5. Symptoms and diagnosis

6. Conclusion: actions to take

Introduction – Tiques – Pathogènes – Transmission/contact – Maladies – Conclusions 1/30

5. Diagnostic and Symptoms

Because diagnostic tests are currently unreliable, the diagnostic should be based on symptoms

But doctors do not agree about which symptoms is related to Lyme and co-infections

Existing list of symptoms are built based on Borrelia species present in the USA or in Germany, the borrelia species found in Belgium influence the type of symptoms found in our country and this should be analysed locally ( per country)

Many symptoms are not specific to Borrelia ( such as fatigue, back pain, head aches) and are thus difficult ot interpret. But sometimes those are the only symptoms and should thus be considered in diagnostic

More than 80 symptoms are listed in the public survey. The frequency of those symptoms in the population with or without Lyme is calculated

39% have been diagnosed for Lyme65% of people diagnosed for Lyme had an erythèma migrans, which is similar to already available numbers for Belgium (63%- Bigaignon, et al. 1989)

Introduction – Tiques – Pathogènes – Transmission/contact – Maladies – Conclusions 1/30

Results available on www.tekentiques.net

Participant listed 191 cases of diagnosed diseases which later revealed to be Lyme Borreliosis instead.

They are most often related to the nervous system (132), the immune system and infectious diseases (20), the squeleton and skin (18).

Fibromyalgia ( including also Tiestze disease, sciatic, cruralgia, nevralgia) and chronic fatigue syndrome ( including also 6 burn out) are two conditions which seems to hide the most misdiagnosis for Lyme disease reach each 18% of the cited misdiagnosis.

Other conditions cited 5 or more times include thyroid problems ( including Ashimoto), back pain, multiple sclerosis and more general symptoms such as anxiety, stress and depression which are more difficult to interpret.

Misdiagnosis

Chronic diseases 200 up to 1500 answers

Table of contents

2. Pathogens

1. Ticks

4. Human cases

3. Human vector contact

5. Symptoms and diagnosis

6. Conclusion

Ticks and Borrelia have been around us for a while

The situation

For unclear reason ticks population (pathogens) have exploded to epidemic level

Current surveillance systems are inadequate and failed to record the increase

Diagnostic tools are inadequate

Prevention measures are poor and lead to many bites and undiagnosed EM

15000 new cases per year in underestimated

Since 2009, the number increased of 50% in the Netherlands

In the Netherlands, doctors are trained to identify EM and patients go to the doctors when they have EM. In Belgium most patients do not go to the doctor for a extending spot and many doctors still do not recognise EM

Doctors disagree about symptoms and treatment: many are left untreated

According to Pr Zeke ( head of medicine faculty BE), When a mother is actively infected, this results in transmission to the child at 75%, including death of the fœtus, are health problems for the new-borne child including mental disorder ( including autistic problems, heart problems,…)

Introduction – Tiques – Pathogènes – Transmission/contact – Maladies – Conclusions 3/34

Good news? There are solutions

Vector-borne diseases offer many opportunity for actions

Reducing human-vector contact

Reducing vectors

To minimise the problem is the worse option and lead to a catastrophic situation

Stop the Ostrich way of handling tick-borne

diseaseCheck what’s happening in the Netherlands

6.1. Reducing tick population

High number of tick bites is detrimental for wildlife too (pheasant, blackbird, robin)

Why? Current high level of abondance is not natural

Transmission of many diseases to wildlife, cattle, domestic animals and humans

37% of tick bites occur in gardens, schools, preschool, public playground

Priority: reduce ticks presence in places of high contact with humans

Land management can help reducing: Cut the grass very shortCreate a dry zone next to forestsImpede access to large wildlife mammalsTreat domestic animals for ticks Check presence of ticks by dragging a white cloth on the ground

4 tick bites per month on children playing in some garden of Brabant wallon

More difficult: reduce population in natural area

Treat cervids and wildboar with acaricid ( on post )

Reduce population of cervids and wild boars

Investigate the use of sheep as mop

Fedor Gassner - RIVM

6.2. Reducing tick bites also in natural settings

Preparation before going in ticks area

At least: Protect hairs (cap of pirate cap) and the area from the navel to the genital part ( thick underwear with tight elastics going up the navel)

Put repelent if needed ( but unknown which ones are efficient)

Put on clothes that makes it difficult for ticks to bite, particularly in places of the body difficult to search for ticks

Put long sleeves and thick trousers inside socks

Inside tick areasAvoid area of abundance an particularly fernsBe careful if you have to urinate in nature – for girls

After Take your clothes off as quickly as possible preferably in the bathWash dierectly your clothes at 60 degrees at least or put in drierBrush your dog before entering the houseCheck the all body, cumb your hair and take a shower

Better inform the population about ticks

Ticks bite directly or wander several hours on clothes and body before biting

Ticks – nymphs are very smallcThey are everywhere in the woods , particularly out of the path

Identify tick/ disease hot spot and give the information to the public

Better information on how to take away the tickDo not press on the belly

Do not put any product on the tick

6.3. Better handling of tick bites

Go to the doctor if you have a extending spot to check if it is EM

Go to the doctor if your health deteriorate or if you have some of the symptoms from the list

Better information on symptoms

Better diagnostic and treatment for the doctor

If EM treat directly with 3 weeks antibiotics without requiring test

If persisting symptoms but no EM, test for Borrelia, Anaplasma, Babesia and Rickettsia

Keep in mind that tests are uncomplete and miss part of the species present in Belgium: concentrate on the symptoms and clinicMany patients are suffering from tick-borne diseases for sometimes a long period without knowing it – search for those patients to help them

6.4. Other

Map borrelia species precisely to help identify symptoms

Check number of borrelia in ticks – high numbers can reduce transmission time to a few hours

Update tick distribution maps to underline risk and trigger better treatment of EM

Test prophylactic use of antibiotics such as the Netherlands

ONE HEALTH approach: in this context, useful to study and manage tick borne diseases together with veterinarian who faces the same challenges and wildlife managers. Wildlife and environmental management could potentially help reduce number of tick and pathogens

Test directly ticks who have biten the human

Build up tests based on species found in Belgium

Merci de votre attentionDes questions?

SVP Diffusez l’enquête ;-)www.tekentiques.net

Journée d’info pour les médecins:Lyme sans frontières, le 6-8 juin à Strasbourg

Contact: valerie.obsomer@uclouvain.betekentiques@gmail.com