blood borne viruses rob hale consultant in special care dentistry king’s college london dental...

Blood Borne VirusesBlood Borne Viruses

Rob HaleRob Hale

Consultant in Special Care Consultant in Special Care DentistryDentistry

King’s College London Dental King’s College London Dental InstituteInstitute

Blood Borne VirusesBlood Borne Viruses

VirusesViruses– HBVHBV– HCVHCV– HIVHIV

StatisticsStatistics– GeneralGeneral– PrisonPrison

Occupation exposuresOccupation exposures Oral health care IssuesOral health care Issues

Hepatitis BHepatitis BVirusVirus

First isolated in 1969First isolated in 1969Virions known as “Dane particles” Virions known as “Dane particles” Hepadna virus with circular DNA Hepadna virus with circular DNA genomegenome

Clinical featuresClinical featuresincubation period of 2-5 monthsincubation period of 2-5 monthsinsidious onset insidious onset asymptomatic infections can occurasymptomatic infections can occursymptoms may includesymptoms may include

short, mild flu-like illnessshort, mild flu-like illnessnausea, vomiting, nausea, vomiting,

diarrhoeadiarrhoealoss of appetite, weight loss of appetite, weight

losslossjaundice, itchy skin, jaundice, itchy skin,

muscle muscle pain, arthralgia, rashpain, arthralgia, rash

Hepatitis BHepatitis B

PathogenesisPathogenesis

infection transmitted infection transmitted parenterallyparenterally

virus replicates in liver virus replicates in liver

viral particles, surface protein viral particles, surface protein shed into bloodshed into blood

About 30% have no signs or About 30% have no signs or symptomssymptoms

Most patients with clinical Most patients with clinical hepatitis will recover hepatitis will recover completely with no untoward completely with no untoward long term effectslong term effects

Hepatitis B - complicationsHepatitis B - complications1.1. Carrier statusCarrier status

HBV persists for > 6 monthsHBV persists for > 6 monthsdevelops in 5-10%develops in 5-10%carriage may persist up to 20 years and be asymptomaticcarriage may persist up to 20 years and be asymptomaticcarrier status more likely in:carrier status more likely in:

those who have received blood productsthose who have received blood productsthose co-infected with HDVthose co-infected with HDVthose with immune defectsthose with immune defects

2.2. Persistent infectionPersistent infectionApprox 5% fail to eliminate the virus completelyApprox 5% fail to eliminate the virus completelyThese at risk include – babies, young children, immunocompromised, These at risk include – babies, young children, immunocompromised, males>femalesmales>femalesongoing liver damage occurs because of host response against infected liver ongoing liver damage occurs because of host response against infected liver cellscells

Chronic infectionChronic infectionChronic persistent hepatitisChronic persistent hepatitisChronic active hepatitis – cirrhosis, liver failureChronic active hepatitis – cirrhosis, liver failure

Hepatocellular carcinomaHepatocellular carcinoma

Treatment for chronic HBV –Treatment for chronic HBV – InterferonInterferonLamivudineLamivudine

Hepatitis B - serologyHepatitis B - serology

AntigensAntigens

Surface antigen Surface antigen ( HBsAg)( HBsAg)

virus replication is occurring in the virus replication is occurring in the liverliver

““e” antigen ( HBeAg)e” antigen ( HBeAg)high level of virus replicationhigh level of virus replicationhigh infectivityhigh infectivity

Core antigen ( HBcAg)Core antigen ( HBcAg)not found in bloodnot found in blood

SerologySerology

Antibody responseAntibody response

Surface antibody (anti- HBs)Surface antibody (anti- HBs)Detectable late in convalescence, indicates immunity following infection, Detectable late in convalescence, indicates immunity following infection,

detectable for life, not found in chronic carriersdetectable for life, not found in chronic carriers

““e” antibody (anti-Hbe)e” antibody (anti-Hbe)Detectable as viral replication falls, indicates low infectivity in a carrierDetectable as viral replication falls, indicates low infectivity in a carrier

Core IgMCore IgMRises early infection and indicates recent infectionRises early infection and indicates recent infection

Core IgGCore IgGRises soon after IgM, present for life in chronic carriers and those who clear Rises soon after IgM, present for life in chronic carriers and those who clear

the virus , indicates exposure to HBVthe virus , indicates exposure to HBV

Hepatitis B - preventionHepatitis B - prevention Active immunisationActive immunisation

– Serum derived Serum derived – Recombinant Recombinant

Three doses induces protective level of antibodies Three doses induces protective level of antibodies Vaccines should be administered toVaccines should be administered to– healthcare workershealthcare workers– sexual partners of chronic carrierssexual partners of chronic carriers– infants of HBV carrier mothersinfants of HBV carrier mothers

Passive antibodyPassive antibodyHep B immune globulin administered to non immune individuals Hep B immune globulin administered to non immune individuals

following single exposure to Hep b infected bloodfollowing single exposure to Hep b infected blood i.e. Needle stick injuriesi.e. Needle stick injuries

Hepatitis CHepatitis CVirusVirus Togavirus with single stranded RNATogavirus with single stranded RNA six genotypes identifiedsix genotypes identified responsible for most cases of “non-A, non B hepatitis”responsible for most cases of “non-A, non B hepatitis” ranks second only to alcoholism as cause of liver damageranks second only to alcoholism as cause of liver damage

Clinical featuresClinical features incubation period of 6-8 weeksincubation period of 6-8 weeks causes a milder form of acute hepatitis than HBVcauses a milder form of acute hepatitis than HBV No signs or symptoms for many on infectionNo signs or symptoms for many on infection Mild, flu-like illness, nausea, vomiting, loss of appetite, weight Mild, flu-like illness, nausea, vomiting, loss of appetite, weight

loss, jaundiceloss, jaundice Many individuals develop chronic infection following exposureMany individuals develop chronic infection following exposure

Hepatitis CHepatitis C

Infection transmitted parenterallyInfection transmitted parenterally

About 20% of individuals will clear the virus within 6 months About 20% of individuals will clear the virus within 6 months but this does not mean they are immune from future but this does not mean they are immune from future infectioninfection

80% will develop chronic hepatitis C infection – remain lifelong 80% will develop chronic hepatitis C infection – remain lifelong carriers/infectiouscarriers/infectious


ComplicationsComplications

Chronic hepatitisChronic hepatitis

Liver cirrhosisLiver cirrhosis

Liver failureLiver failure

Liver cancer Liver cancer (<3%)(<3%)

TreatmentTreatment

InterferonInterferon

RibavirinRibavirin

HIV/AIDSHIV/AIDS

HIVHIV

Human immunodeficiency virusHuman immunodeficiency virus

AIDSAIDS

Acquired immunodeficiency syndrome Acquired immunodeficiency syndrome

What’s the difference?What’s the difference?

HIVHIV

RNA virus

Reverse transcriptase

Transmitted parenterally

HIV antibody testHIV antibody test

ELISAELISA

Western blotWestern blot

A positive test A positive test indicates:indicates:

Exposure to the Exposure to the virusvirus

Persistent infectionPersistent infection InfectiousnessInfectiousness

It does not indicate It does not indicate AIDSAIDS

HIV ProgressionHIV Progression

Becoming HIV antibody positiveBecoming HIV antibody positive Seroconversion illnessSeroconversion illness Asymptomatic HIV infectionAsymptomatic HIV infection Symptomatic HIV infectionSymptomatic HIV infection AIDS diagnosisAIDS diagnosis

Medical monitoringMedical monitoring

FBCFBC

CD4CD4– 600- 1600 600- 1600

cells/mm3cells/mm3

Viral loadViral load

Medical MonitoringMedical Monitoring

CD4CD4 Monitors immune systemMonitors immune system Help decide when to start therapyHelp decide when to start therapy Monitor effectiveness of drugsMonitor effectiveness of drugs

Viral LoadViral Load Identifies number of HIV particlesIdentifies number of HIV particles Help decide when to start therapyHelp decide when to start therapy Monitors effectiveness of drugsMonitors effectiveness of drugs

MedicationMedication

Highly active antiretroviral therapy Highly active antiretroviral therapy (HAART(HAART– Reverse transcriptase inhibitorsReverse transcriptase inhibitors

Nucleoside analogues ( AZT,ddI, ddC, d4T)Nucleoside analogues ( AZT,ddI, ddC, d4T) Non-nucleoside analogues ( nevirapine)Non-nucleoside analogues ( nevirapine)

– Protease inhibitorsProtease inhibitors Saquinavir, Retonavir etcSaquinavir, Retonavir etc

Combination therapyCombination therapy

Side effects of medicationSide effects of medication

TirednessTiredness Back painBack pain FeverFever NauseaNausea HeadacheHeadache VomitingVomiting DiarrhoeaDiarrhoea Abdominal painAbdominal pain Skin rashSkin rash

Changes in tasteChanges in taste Burning sensation of Burning sensation of

skinskin Muscle painMuscle pain Peripheral neuropathyPeripheral neuropathy Mouth ulcersMouth ulcers ConstipationConstipation InsomniaInsomnia LipodystrophyLipodystrophy

Transmission of Blood Borne Transmission of Blood Borne VirusesViruses

Body fluidsBody fluids

RouteRoute

TransmissionTransmission Blood/blood productsBlood/blood products

Organ donationOrgan donation

Sexual intercourseSexual intercourse

Artificial insemination with infected semenArtificial insemination with infected semen

Horizontal transmission Horizontal transmission

Vertical transmissionVertical transmission

Unknown – Hep CUnknown – Hep C

StatisticsStatistics

Hepatitis CHepatitis C Approx 191,000 individuals between 15-59 years with Approx 191,000 individuals between 15-59 years with

antibodies to Hep C in England & Wales in 2003antibodies to Hep C in England & Wales in 2003

Equates to approx 142,000 individuals with chronic Hep C Equates to approx 142,000 individuals with chronic Hep C infectioninfection

Approx 0.4% of general populationApprox 0.4% of general population

In Scotland, approx 50,000 infected of which 38,000 have In Scotland, approx 50,000 infected of which 38,000 have chronic infectionchronic infection

Northern Ireland approx 4000 individuals likely to be Northern Ireland approx 4000 individuals likely to be infectedinfected


Difficult to estimate new infection rates Difficult to estimate new infection rates due to long time between infection and due to long time between infection and development of severe disease/deathdevelopment of severe disease/death

Increase in incidence until late 1980s Increase in incidence until late 1980s peaking at about 14,900 in 1988peaking at about 14,900 in 1988

Larger degree of uncertainty of Larger degree of uncertainty of estimates for later yearsestimates for later years


Wide variation of HCV incidence in injecting drug Wide variation of HCV incidence in injecting drug users users

England England 3.01- 41.8%3.01- 41.8%

ScotlandScotland 11.9 – 28.4 % 11.9 – 28.4 %

Establishing contribution of this incidence to future Establishing contribution of this incidence to future prevalence of infection requires knowledge of IDU prevalence of infection requires knowledge of IDU populationpopulation

2004 study estimated between 100,000 – 150,000 2004 study estimated between 100,000 – 150,000 current injectors in England in 2000current injectors in England in 2000

HIVHIV Estimated 77,400 persons living with HIV in UK by end of 2007Estimated 77,400 persons living with HIV in UK by end of 2007

During 2007 7,743 new diagnosesDuring 2007 7,743 new diagnoses– 55% heterosexual contact – majority acquired HIV abroad55% heterosexual contact – majority acquired HIV abroad– 41% MSM41% MSM

70% of persons seen for HIV care were receiving antiretroviral 70% of persons seen for HIV care were receiving antiretroviral therapytherapy

Almost one in five with severe immunosuppression were not on Almost one in five with severe immunosuppression were not on therapytherapy

Almost a third of persons newly diagnosed were diagnosed late Almost a third of persons newly diagnosed were diagnosed late – At a point at which therapy should have begun (CD4<200 )At a point at which therapy should have begun (CD4<200 )

HIV and hepatitis in prisonsHIV and hepatitis in prisonsGlobally rates of HIV and hepatitis in prisons are higher than Globally rates of HIV and hepatitis in prisons are higher than

general populationsgeneral populations

HIVHIVEngland & Wales in 1997 – England & Wales in 1997 –

0.3% adult males, 1.2% adult females0.3% adult males, 1.2% adult femalesScotland in 1997 – Scotland in 1997 –

0.3% adult males, 0.6% adult females0.3% adult males, 0.6% adult females

Hepatitis CHepatitis CEngland & Wales in 1997 – England & Wales in 1997 –

9% adult males and 11% adult females9% adult males and 11% adult femalesScotland –Scotland –

8% adult males, 14.8% adult females8% adult males, 14.8% adult females

HIV and hepatitis in prisonsHIV and hepatitis in prisons

Since 1997 prison population has increased Since 1997 prison population has increased by approx 29%by approx 29%

Has the number of prisoners infected with Has the number of prisoners infected with blood borne viruses also increased by this blood borne viruses also increased by this amount or more?amount or more?

Nature of prison populationNature of prison population Risks of transmission specific to prison Risks of transmission specific to prison

environmentenvironment

Nature of prison populationNature of prison population

High risk for infection even before High risk for infection even before imprisonmentimprisonment

IV drug usersIV drug users 29% female, 24% male, 4% young offenders29% female, 24% male, 4% young offenders

>90% HCV infections are through IVDU>90% HCV infections are through IVDU

Risks of transmission specific to Risks of transmission specific to prison environmentprison environment

IVDUIVDU

– One in five prisoners report having used heroin at One in five prisoners report having used heroin at some time whilst in prison (SSD/NAC 2005)some time whilst in prison (SSD/NAC 2005)

– Sharing of needles/equipmentSharing of needles/equipment

Risks of transmission specific Risks of transmission specific to prison environmentto prison environment

Sexual activitySexual activity

– 2% of a sample of 208 prisoner participants had had 2% of a sample of 208 prisoner participants had had forced penetrative sexual intercourse (2004)forced penetrative sexual intercourse (2004)

– In a population of approx 75,000 – how many In a population of approx 75,000 – how many victims would that make!victims would that make!

– How many new infections?How many new infections?– Overcrowding, mental health problems, inadequate Overcrowding, mental health problems, inadequate

staff levels, absence of conjugal rights, homophobia, staff levels, absence of conjugal rights, homophobia, general intolerance, restriction of condomsgeneral intolerance, restriction of condoms

– Sexual behaviour in situation of intimidation and Sexual behaviour in situation of intimidation and violence – more risk of tearing and bleedingviolence – more risk of tearing and bleeding

Risks of transmission specific to Risks of transmission specific to prison environmentprison environment

ViolenceViolence– Fights/assaultsFights/assaults– One in 10 men reported being assaultedOne in 10 men reported being assaulted– Gross under reportingGross under reporting– When bleeding occurs – may be low risk for HIV but greater for HCVWhen bleeding occurs – may be low risk for HIV but greater for HCV

TattooingTattooing– Sharing tattooing equipmentSharing tattooing equipment– 11% of study sample had been tattooed in prison11% of study sample had been tattooed in prison– Fifth of those who had been tattooed had been tattooed whilst in prison Fifth of those who had been tattooed had been tattooed whilst in prison

(Strang 1998)(Strang 1998)

Occupational Occupational ExposureExposure

Occupational Exposure

Since 1997 in UK:Since 1997 in UK:

3773 OE to blood or other high-risk body 3773 OE to blood or other high-risk body fluidfluid

1595 of these from London1595 of these from London

76% were percutaneous injuries76% were percutaneous injuries

Occupational exposureRisk of infection following a percutaneous injury:Risk of infection following a percutaneous injury:

HBVHBV 1 in 31 in 3

HCVHCV 1 in 301 in 30

HIV HIV 1in 3001in 300Department of HealthDepartment of HealthHIV Prophylaxis : Guidance from the UK Chief Medical officers Expert Advisory Group on AIDS HIV Prophylaxis : Guidance from the UK Chief Medical officers Expert Advisory Group on AIDS September 2008From 2000-2007September 2008From 2000-2007

68% attributed to hollow bore needles68% attributed to hollow bore needles19% solid needles19% solid needles13% “other sharps” e.g scalpels, dental probes13% “other sharps” e.g scalpels, dental probesUnited Kingdom Surveillance of Significance Occupational Exposures to Blood Borne Viruses in Healthcare Workers 2008United Kingdom Surveillance of Significance Occupational Exposures to Blood Borne Viruses in Healthcare Workers 2008

Occupational Exposure

Deep penetrating injuries with hollow bore Deep penetrating injuries with hollow bore needlesneedles

Device visibly contaminated with bloodDevice visibly contaminated with blood

Needle from source patient's artery or veinNeedle from source patient's artery or vein

Terminal HIV related illness in source patientTerminal HIV related illness in source patient

Exposures to HCV,HIV HBVExposures to HCV,HIV HBV

VirusVirus Type of Type of exposureexposure

Total Total exposuresexposures

seroconversioseroconversionsns

Hepatitis CHepatitis C PercutaneousPercutaneous 1389 (37%)1389 (37%) 1212

MucocutaneousMucocutaneous 417 (11%)417 (11%)

HIVHIV PercutaneousPercutaneous 656 (17%)656 (17%) 55


Hepatitis BHepatitis B PercutaneousPercutaneous 242 (6%)242 (6%)


Co-infectedsCo-infecteds PercutaneousPercutaneous 212 (6%)212 (6%) 2 (HCV)2 (HCV)


All exposuresAll exposures PercutaneousPercutaneous 2855 (76%)2855 (76%) 1515


UnknownUnknown 16 (0%)16 (0%)

Exposures to HCV, HIV, HBVExposures to HCV, HIV, HBV

Of 15 seroconversions in UK:Of 15 seroconversions in UK:

One dentist seroconverted to HCV One dentist seroconverted to HCV reported in 2001reported in 2001

Key recommendationsKey recommendations Injuries with hollow bore needles remain most commonly Injuries with hollow bore needles remain most commonly

reported occupational exposure in healthcare settingreported occupational exposure in healthcare setting

HCV exposures remain greatest proportion of percutaneous HCV exposures remain greatest proportion of percutaneous exposuresexposures

HCWs exposed to HCV positive source patient still HCWs exposed to HCV positive source patient still not not receiving follow-up testing in line with national guidancereceiving follow-up testing in line with national guidance

No new HIV seroconversions since 1999No new HIV seroconversions since 1999

78% HCWs exposed to HIV positive source patient began PEP. 78% HCWs exposed to HIV positive source patient began PEP.

37% within an hour and 89% within 24 hours37% within an hour and 89% within 24 hours

Post exposure prophylaxisPost exposure prophylaxis Truvada ( 300mg Tenofovir/200mg Emtricitabine) once a dayTruvada ( 300mg Tenofovir/200mg Emtricitabine) once a day

(nucleoside reverse transcriptase inhibitor)(nucleoside reverse transcriptase inhibitor)

2 Kaletra film-coated tablets ( 200mg Lopinavir/50mg 2 Kaletra film-coated tablets ( 200mg Lopinavir/50mg Ritonavir) twice a day Ritonavir) twice a day (protease inhibitor)(protease inhibitor)

PEP as soon as possible after exposure, ideally within an hour PEP as soon as possible after exposure, ideally within an hour following careful risk assessmentfollowing careful risk assessment

PEP now generally not recommended after 72 hours post PEP now generally not recommended after 72 hours post exposureexposure

Follow –up Follow –up 12 weeks after exposure12 weeks after exposureIf PEP taken for at least 12 weeks from when If PEP taken for at least 12 weeks from when

PEP PEP stoppedstoppedLonger follow-up for complex/co-infected casesLonger follow-up for complex/co-infected cases

Side effectsSide effectsTruvadaTruvada

gastrointestinal disturbances gastrointestinal disturbances

(vomiting, abdominal pain, (vomiting, abdominal pain, faltualence, diarrhoea)faltualence, diarrhoea)

anorexia, pancreatitis, liver damageanorexia, pancreatitis, liver damage

dyspnoea, cough, headachedyspnoea, cough, headache

insomnia, dizziness, fatigueinsomnia, dizziness, fatigue

blood disorders (anaemia, blood disorders (anaemia,

neutropenia, thrombocytopenia)neutropenia, thrombocytopenia)

myalgia, arthralgia, rash, urticaria, myalgia, arthralgia, rash, urticaria, feverfever

Lypodystrophy, Lypodystrophy,

Kaletra

gastrointestinal disturbances gastrointestinal disturbances

(vomiting, abdominal pain, (vomiting, abdominal pain, faltualence, diarrhoea)faltualence, diarrhoea)

anorexia., hepatic dysfunction, anorexia., hepatic dysfunction,

pancreatitis,pancreatitis,

blood disorders (anaemia,blood disorders (anaemia,

neutropenia, thrombocytopenia)neutropenia, thrombocytopenia)

sleep disturbances, headache, sleep disturbances, headache,

dizziness, fatigue, parathesia,dizziness, fatigue, parathesia,

Myalgia, myositis, rhabdomyolysis,Myalgia, myositis, rhabdomyolysis,

taste disrturbances, rash, pruritis, taste disrturbances, rash, pruritis,

Steven-Johnsons syndrome, Steven-Johnsons syndrome,

lypodystrophylypodystrophy

What if a healthcare What if a healthcare worker becomes worker becomes

infected?infected?

Infected Health Care Infected Health Care WorkersWorkers

Seek confidential professional advice if Seek confidential professional advice if believe to have been exposedbelieve to have been exposed

Majority procedures in health care setting Majority procedures in health care setting pose no riskpose no risk

Those infected must seek expert medical Those infected must seek expert medical adviceadvice

Avoid exposure prone proceduresAvoid exposure prone procedures

The majority of procedures in dentistry are The majority of procedures in dentistry are exposure prone exceptexposure prone except

Exam with mouth mirrorsExam with mouth mirrors Taking extra-oral radiographsTaking extra-oral radiographs Visual/digital exam of head & neckVisual/digital exam of head & neck Visual/digital exam of edentulous Visual/digital exam of edentulous

mouthmouth Taking impressions of edentulous Taking impressions of edentulous

mouthmouth Construction & fitting of full denturesConstruction & fitting of full dentures

Oral Health CareOral Health Care

(Decontamination and (Decontamination and infection control – goes infection control – goes

without saying)without saying)

Oral health careOral health care

HepatitisHepatitis

Drug metabolismDrug metabolism Bleeding tendenciesBleeding tendencies Liaise with liver physicianLiaise with liver physician PreventionPrevention

Dental treatment for HIV Dental treatment for HIV antibody positive individualsantibody positive individuals

BleedingBleeding– ThrombocytopeniaThrombocytopenia

InfectionsInfections– NeutropeniaNeutropenia– Antibiotic prophylaxisAntibiotic prophylaxis

Wound healingWound healing

Local anaesthesiaLocal anaesthesia– Indinavir reactionIndinavir reaction

Oral Manifestations of HIV Infection

Group 1Group 1 - Lesions strongly - Lesions strongly associated with HIV infectionassociated with HIV infection

Group 2Group 2 – Lesions less commonly – Lesions less commonly associated with HIV infectionassociated with HIV infection

Group 3Group 3 – Lesions seen in HIV – Lesions seen in HIV infection infection

Lesions strongly associated with HIV infection

Candidiasis -Candidiasis - pseudomembranouspseudomembranouserythematouserythematous

Oral hairy leukoplakiaOral hairy leukoplakia Necrotising ulcerative gingivitisNecrotising ulcerative gingivitis Necrotising ulcerative periodontitisNecrotising ulcerative periodontitis Kaposi’s sarcomaKaposi’s sarcoma Non-Hodgkin’s lymphomaNon-Hodgkin’s lymphoma

General ConsiderationsGeneral Considerations The principles of good oral health care are the The principles of good oral health care are the

same for patients with blood borne virusesas they same for patients with blood borne virusesas they are for all patients.are for all patients.

There is no justification for modifying dental There is no justification for modifying dental treatment based solely on status.treatment based solely on status.

Alterations may be indicated on the basis of Alterations may be indicated on the basis of medical problems that occur as a result of medical problems that occur as a result of infection.infection.

Consider each patient individually.Consider each patient individually.

General ConsiderationsGeneral Considerations

Despite the immunological problems Despite the immunological problems resulting from HIV infection, few resulting from HIV infection, few complications from dental treatment have complications from dental treatment have been reported.been reported.

The successful management of any oral The successful management of any oral manifestations and good oral health care manifestations and good oral health care can improve the quality of life for the can improve the quality of life for the patient.patient.

““Prisons are breeding grounds for blood-Prisons are breeding grounds for blood-borne viruses because they bring together borne viruses because they bring together a population with a disproportionate rates a population with a disproportionate rates of high-risk behaviours in overcrowded of high-risk behaviours in overcrowded and adverse conditions”and adverse conditions”

Dame Ruth RuncimanDame Ruth Runciman

National AIDS Trust ChairNational AIDS Trust Chair

Prison Reform Trust Deputy Chair Prison Reform Trust Deputy Chair

HIV and hepatitis in UK prisons: addressing prisoners’ healthcare needs(2005)HIV and hepatitis in UK prisons: addressing prisoners’ healthcare needs(2005)

blood borne viruses rob hale consultant in special care dentistry king’s college london dental...

Documents