6/3/2011dr. salwa tayel (brucellosis)1 6/3/2011dr. salwa tayel (brucellosis)2 associate professor...

6/3/2011 Dr. Salwa Tayel (Brucellosis) 1

6/3/2011 Dr. Salwa Tayel (Brucellosis) 2

Associate Professor Associate Professor Family and Community Medicine DepartmentFamily and Community Medicine Department

King Saud UniversityKing Saud University

ByBy

BrucellosisBrucellosis

Dr. Salwa TayelDr. Salwa Tayel

6/3/20116/3/2011Dr. Salwa Tayel (Brucellosis)Dr. Salwa Tayel (Brucellosis)33


• Brucellosis is primarily a disease affecting Brucellosis is primarily a disease affecting

animals. It can be transmitted to humans. animals. It can be transmitted to humans.

• Brucellosis is a major health and economic Brucellosis is a major health and economic

problem in many parts of the world .problem in many parts of the world .

• It is an old disease, It is an old disease, Sir David Bruce,Sir David Bruce, isolated the isolated the

causative agent from a soldier incausative agent from a soldier in Malta in Malta in 18861886

• ItIt remains remains the commonest zoonotic disease the commonest zoonotic disease

worldwide.worldwide.


• CLINICAL FEATURES: Acute systemic disease characterized by: - acute or insidious fever (continuous, intermittent, or irregular)

- headache, - weakness, - sweating, - arthralgia - weight loss. ± enlarged liver and spleen


Duration: days, months, years with relapses:

< 8 wks Acute 8 wks – one year undulant

> one year Chronic

Complications: Osteoarthritis 20-60%

Genitourinary 2-20%


• SubclinicalSubclinical and unrecognized infections are more and unrecognized infections are more frequent than clinical one.frequent than clinical one.

• It is usually a It is usually a self-limiting disease.self-limiting disease.

• 50% of cases regain their health in one year.50% of cases regain their health in one year.

• Untreated clinical illness may become Untreated clinical illness may become chronic. chronic.

• The death rate of untreated brucellosis is The death rate of untreated brucellosis is about 2%.about 2%.• Death is usually due to Death is usually due to bacterial endocarditis.bacterial endocarditis.


Magnitude of the problemMagnitude of the problem

Globally:Globally:

• More than 500 000 new human cases of More than 500 000 new human cases of

brucellosis annually brucellosis annually

• Associated with substantial residual Associated with substantial residual

disabilitydisability

• An important cause of travel-associated An important cause of travel-associated

morbidity.morbidity.


The new global map of human brucellosisThe new global map of human brucellosis 20062006


The global epidemiology of human brucellosis has The global epidemiology of human brucellosis has

drastically changed over the past decade drastically changed over the past decade

because of:because of:

– various sanitary, various sanitary,

– Socioeconomic,Socioeconomic,

– political reasonspolitical reasons

– the evolution of international travel. the evolution of international travel.

The new global map of human brucellosisThe new global map of human brucellosis


• Countries traditionally considered to be Countries traditionally considered to be

endemic -e.g. endemic -e.g. FranceFrance, , IsraelIsrael, and most of , and most of

Latin AmericaLatin America,,

• Now, they achieved Now, they achieved controlcontrol of the disease. of the disease.

• New fociNew foci of human brucellosis have of human brucellosis have

emerged, particularly in central Asiaemerged, particularly in central Asia

The new global map of human brucellosisThe new global map of human brucellosis


Middle East & AsiaMiddle East & AsiaThe situation in central and western Asia is The situation in central and western Asia is dramaticdramatic::

• Syria has the highest annual incidence worldwide Syria has the highest annual incidence worldwide

reaching an alarming 1603 cases per million per yearreaching an alarming 1603 cases per million per year

• Mongolia, is ranked second (605·9 cases per million)Mongolia, is ranked second (605·9 cases per million)

***In USA the annual incidence of 0·48 cases per million ***In USA the annual incidence of 0·48 cases per million

for last ten years (only 100-200 cases annually)for last ten years (only 100-200 cases annually)


Incidence Incidence (annual cases per million population)(annual cases per million population)

• Syria 1,603·4

• MongoliaMongolia 605·9605·9

• Iraq 278·4

• Turkey 262·2

• Iran 238·6

• Saudi Arabia 214·4


Situation in Saudi Arabia:Situation in Saudi Arabia:

• Distribution:

Central & Eastern regions & Asir

• Regional endemicity varies in Saudi Arabia

due to climatic factors:

• rainy season---- increased grass

growth.


Situation in Saudi Arabia:Situation in Saudi Arabia:

• Between 1956 and 1982Between 1956 and 1982

– only Sporadic human cases of brucellosis.only Sporadic human cases of brucellosis.

• During early 1980s:During early 1980s:

– brucellosis emerged as a major public brucellosis emerged as a major public

health problem. health problem.


Reasons of the surge in incidence of brucellosis:Reasons of the surge in incidence of brucellosis:

• Intensive sheep/cattle breeding projects Intensive sheep/cattle breeding projects

– minimal veterinary resourcesminimal veterinary resources

• Uncontrolled importation of live animals both for Hajj Uncontrolled importation of live animals both for Hajj

periods and for commercial reasons.periods and for commercial reasons.

– They were poorly screened for infectionThey were poorly screened for infection

• In addition to, prevailing local custom of drinking raw In addition to, prevailing local custom of drinking raw

and warm milk of sheep, goats, and camels, among and warm milk of sheep, goats, and camels, among

the population of nomadic backgroundthe population of nomadic background..


VotingVoting

Miss Goat Universe Miss Goat Universe

الماعز جمال الماعز ملكة جمال ملكة


AgentAgent

Susceptible HostSusceptible Host ReservoirReservoir

Mode of transmissionMode of transmission

Cycle of infectionCycle of infection

Portal of ExitPortal of ExitPortal of InletPortal of Inlet

IP

PC


Agent:

Brucella species; Gram negative, coccobacilli bacteria,Gram negative, coccobacilli bacteria, strictly parasiticstrictly parasitic and prefer the and prefer the intracellular habitat. intracellular habitat.

Reservoir:

Cattle, Sheep and Goat & camel, Swine, …….


SpeciesNatural

host

Other animal species affected

Human disease

Brucella abortusCattleWild animals, water buffalo, camels

Less severe

Brucella melitensisSheep and

Goat & camel

Wild ruminant cattle

Severe

Brucella suisSwineVarious wild species

Severe ( except biovar 2)

Brucella canisDogNoneBenign

Brucella species and main reservoirs. Brucella species and main reservoirs.


Resistance of brucellaHeating at 60ºCFor 10 minutes

Phenol 1%For 15 minutes

Direct sunlightIn a few hours

MilkFor several days

Milk(till the milk turns sour)

Fresh cheeseFor 3 months

Tap-waterFor 57 days

Human urineFor 1 week

DustFor 6 weeks

Damp soilFor 10 weeks

Animal fecesFor 100 days


The most important route of animal to human transmission of Brucella


1.1. IngestionIngestion

• Consumption of potentially infected Consumption of potentially infected

unpasteurized milk, milk products, or milk, milk products, or

meat.meat.

• UnpasteurizedUnpasteurized cheese, called "village cheese, called "village

cheese," from endemic areas is a cheese," from endemic areas is a

particular risk for particular risk for touriststourists.

• Rarely through undercooked meat


2.2. Direct contactDirect contact of c of conjunctiva or broken skin with blood, urine, aborted fetus, the with blood, urine, aborted fetus, the placenta and the discharge from vagina of placenta and the discharge from vagina of infected animals.infected animals.

• Accidental self inoculation of vaccines. Accidental self inoculation of vaccines.

High Risk GroupsHigh Risk Groups

• slaughter-house workers, meat inspectors, animal handlers and veterinarians.


3.3. Inhalation of aerosols containing the bacteria.Inhalation of aerosols containing the bacteria.

– Or aerosol contamination of the conjunctivaOr aerosol contamination of the conjunctiva

• In the lab, transmission is via aerosolization In the lab, transmission is via aerosolization

High Risk GroupsHigh Risk Groups

• Laboratory workers.Laboratory workers.


Can brucellosis be spread from person to person?

• Human-to-human transmission is rare. – Bone marrow transplantation from infected

donors– Blood transfusion– Sexual intercourse– Neonatal infection; trans-placental or during

delivery– Or probably through breast milk.


SummarySummary• In the Middle East and Africa ingestion of contaminated In the Middle East and Africa ingestion of contaminated

dairy products is an important route of infection. dairy products is an important route of infection.

• In USA, Human brucellosis is primarily an occupational In USA, Human brucellosis is primarily an occupational

hazard (Lab, Vet)hazard (Lab, Vet)

• Whether human beings can become infected via person-to-Whether human beings can become infected via person-to-

person spread is rare or uncertain.person spread is rare or uncertain.• Incubation period varies

– 7-21 days to several months• Brucellosis is not communicable from man to man.


PreventionPrevention

1. Eradication of brucellosis in 1. Eradication of brucellosis in animalsanimals is the key is the key

to prevention in humans. to prevention in humans.

– Surveillance, serologic testing, quarantine and Surveillance, serologic testing, quarantine and

massive immunization of animals in areas massive immunization of animals in areas

with high infection rateswith high infection rates

– Legislation to control marketing and Legislation to control marketing and

movement of animals.movement of animals.


2. Brucellosis acquired from milk is preventable 2. Brucellosis acquired from milk is preventable

through:through:

• Legislation to pasteurization of milk and dairy Legislation to pasteurization of milk and dairy

products. products.

• Public health education to avoid drinking untreated Public health education to avoid drinking untreated

milk and dairy products.milk and dairy products.

3. Health education for those 3. Health education for those occupationallyoccupationally at risk at risk

(Use of Safety measures).(Use of Safety measures).

PreventionPrevention


Vaccination?!Vaccination?!

• A humanA human BrucellaBrucella vaccine vaccine does not existdoes not exist. .

• For animals: all are live-attenuated.For animals: all are live-attenuated.

• Currently, B. abortus RB51 is used to Currently, B. abortus RB51 is used to

immunize cattleimmunize cattle

• B. melitensis REV.1 is used to immunize B. melitensis REV.1 is used to immunize

goats and sheep.goats and sheep.


ThanThank youk [email protected]

Bibliotheca Alexandrina

6/3/2011dr. salwa tayel (brucellosis)1 6/3/2011dr. salwa tayel (brucellosis)2 associate professor...

Documents

salwa tayel slide

salwa tayel brucellosis1

old disease

selflimiting disease

spleen slide

commonest zoonotic disease

acute systemic disease

untreated clinical illness