Migration, public health and compulsory screening for TB and HIV Richard Coker 8 th October 2003

The purpose of screening Epidemiological trends What risk? Effective tools, effective policies? Will compulsion improve effectiveness? Conclusions

On the agenda Read This And Get Angry Sun, 29 Jan 2003 The Secret Threat to British Lives The Spectator, 25 Jan 2003 No System to Abuse: immigration and health care in the UK Centre for Policy Studies, May 2003, Before Its Too Late: A New Agenda for Public Health Conservative Party consultation paper, August 2003 Inquiry into Imported Infections Cabinet Office, announced Jan 2003 Migration and HIV: Improving Lives in Britain All- Party Parliamentary Group on AIDS, July 2003

Before Its Too Late Advocates 3 tests before permission given to remain in the UK: 1.They must not pose a risk of transmitting an infectious disease to the public 2.They must not create undue demand on restricted health resources 3.They must not create a long-term drain on the public purse those entering the UK through the immigration system would require [sic] to have such tests at the point of application and to pay for them, whilst those seeking asylum would be detained until it was clear the criteria had been met

Purpose of Screening To identify individuals with infection in order to provide the appropriate care and treatment for that individual To prevent public health consequences of undetected infectious disease through case detection

Tuberculosis: key national facts (1) Tuberculosis case reports, by geographic origin, England and Wales, Since 1988, number of cases of TB and the rate has increased Proportion born abroad has also increased Poverty, overcrowding, exposure risk Treatment of TB costs approx. £6,000

Tuberculosis: key national facts (2) Tuberculosis case reports born abroad by time since entry into the UK Half of those born abroad who develop TB do so within 5 years Perhaps 0.3% of asylum seekers have TB at port screening, and of these only ¼ have infectious disease Number of cases detected through Heathrow represents less than 0.5% of cases Asylum seekers represent a fraction of immigrants – but it is principally asylum seekers who are currently screened In one study, screening systems failed to identify 60% of new immigrants with TB

Immigrant-associated TB: a public health threat? Evidence from many sources –US states with high levels of TB in foreign-born persons do not correspondingly have high rates in those born in US –From DNA finger-printing, most TB in London is reactivation –From Denmark a study showed that transmission between immigrants and native-born Danes almost non-existent Correlation between State-Specific Tuberculosis Case Rates for Foreign-Born Persons and U.S.-Born Persons in the United States, 1986 to 1993

HIV: key facts (1) Heterosexually acquired infection by sub-category of heterosexual exposure At end 2001, estimated 41,000 adults living with HIV in the UK Proportion infected through heterosexual sex is increasing Most heterosexually- acquired HIV is acquired or linked to abroad (71% to Africa) Sex between men & women (total)No evidence "high risk" partner: Exposure abroad No evidence "high risk" partner: Exposure UKExposure to "high risk" partner Year of diagnosis Number of diagnoses

Immigrant-associated HIV: a public health threat? Of 2,046 individuals infected in the UK, at least half were infected through heterosexual sex with someone originating from outside Europe London-based study suggested that 9% of heterosexually-acquired HIV in black Africans acquired in UK Migrants returning Potentially many people unaware and unsuspecting of their HIV status (black Africans > white)

2 cardinal questions: Does screening detect those with the condition? Will screening assist in achieving the desired public health objective?

Does screening detect those with the condition? HIV: it depends TB: it depends

Screening for HIV The tests are sensitive and specific But focused screening may assume –That immigrants from high prevalence countries have prevalence rates that reflect donor countries –That populations freely able to move dont pose a threat (new eastern European border) –That those not screened will be served by other systems (illegal immigrants, transient populations)

X-rays to detect TB Theoretical population with prevalence rate of 600/100,000 10,000 immigrants screened Theoretical population with prevalence rate of 40/100,000 10,000 immigrants screened Expected number of cases of disease 604 Number of cases of TB detected through X- ray screening 453 Number of cases of TB missed through X- ray screening 151 Number of people without TB, but classified as having TB 100 Proportion of people identified with TB who actually have it 31%3%

X-ray at screening and 6 months later, Swiss asylum seeker

Will screening assist in achieving the desired public health objective? TB –Evidence is lacking No clinical trials DH-funded transmission and economic model due to report shortly HIV –Screening only confers public health benefit if effective action follows –Evidence is lacking

Refusing entry to HIV-infected immigrants –May reduce burden of disease, costs, and future transmission –May stigmatise, ensure evasive practices –How often should people be screened? –Illegal in asylum seekers Should they be isolated? For how long? Does the risk arise because of status or behaviour?

Coercion and protection of the public health

Long historical tradition, with little evidence of benefit of detention or compulsory screening May show that the government is seen to be taking firm, decisive action and the epidemic appears to be under control (Panos Institute) Coercive measures may be counterproductive

Public Health Authorities Bear the Burden of Justification

Conclusion (1) Increases in HIV and TB rates are linked to immigration, but have been difficult to quantify These changes may reflect, in part, global trends Most TB occurs in people after entry There is probably a substantial population of HIV- infected people in the UK unaware of their status who pose a public health challenge

Conclusion (2) Evidence-base to support TB screening of immigrants is weak Screening tests for TB lack validity Screening tests for HIV are reliable Evidence is lacking regarding screening immigrants for HIV Significant ethical, moral, legal and practical issues are raised with coercive measures Coercive screening practices may result in unforeseen perverse consequences

Purpose of Screening To identify individuals with infection in order to provide the appropriate care and treatment for that individual To prevent public health consequences of undetected infectious disease through case detection