DISCAPACIDAD EN EL ADULTO MAYOR

Women in the US

Estimates of the prevalence of HIV Infection In Industrialised countries are now largely based on the results of unlinked anonymous seroprevalence studies undertaken In women attending antenatal clinics and STD clinic attenders. In the US an extensive programme of Unlinked-Anonymous HIV surveillance Is In progress. Studies In women attending antenatal clinics have emphasised the variability of HIV prevalence In different areas. The mid-Atlantic, south-eastern States and Puerto Rico have the highest seroprevalence, while urban populations generally have higher levels of Infection than rural populations (Johnson, 1992). A survey to estimate prevalence of HIV Infection among childbearing women Is conducted In 44 states, the District of Columbia, Puerto Rico, and the U. S. Virgin Islands. The survey. Initiated In most states In 1988-89, Is based on the systematic, unlinked testing for HIV-antlbody of residual blood specimens routinely collected on filter paper from newborn Infants for metabolic screening. Consecutive births during a survey period of at least 3 months per year are sampled In each state. Between January 1988 and December 1992, 9 million unlinked specimens, representing nearly one half of all live births during that period, were tested for maternal HIV- antlbody In state public health laboratories. The weighted seroprevalence estimate for childbearing women nationwide was 0.17% In 1991-1992 (Centers for Disease Control and Prevention, 1994). The seroprevalence was 3 to 28 times higher among black women compared to white women. State specific seroprevalence ranged from 0.0% to 0.6% with the highest along the Atlantic Coast. Only one state had no HIV-Infected childbearing women. Prevalence changed regionally showing an Increase In the Southern States and a decrease In the North-eastern states. Overall a slight Increase was seen from 0.16% In 1989-1990 to 0.17% In 1991-1992. Another female population group, those attending Reproductive Health Clinics for family planning, prenatal care and abortion were tested using the Unllnked-

Anonymous method. Although the median clinic HIV seroprevalence was higher (0.2%) than in the study of childbearing women, the geographic spread was similar. Women age 25-29 years generally had the highest seroprevalence as did black women (0.4%), compared to white and Hispanic. No change over time was evident. Seroprevalence from injecting drug users entering drug treatment centres showed a median percent positive of 6.3% for women compared with 7.5% for men. Large inter-regional differences were seen between 0.7% and 40% with North-eastern followed by Atlantic coast states having the highest seroprevalence.

In persons entering adult correctional facilities the seroprevalence among women was a median of 5.1% compared with 2.3% for men, a similar regional variation was seen, 24% of women entering a correctional facility in New York were infected with HIV. Adolescent Medicine Clinics showed a rising HIV seroprevalence with

increasing age from 0.2% in persons less than 15 years to 0.5% among those 20 to 24 years. Male to female ratio was approximately 1:1.

The Job Corps is a residential occupational training program for urban and rural disadvantaged youth ages 16-21 years. From 1988 to 1992, the number of males infected with HIV has decreased and females increased so now females especially if black have a higher seroprevalence than males (including black males). This points to heterosexual spread as younger girls have sex with older men who have a higher seroprevalence than younger men.

Among military recruits where intravenous drug users, men who have sex with men and persons who suspect they are infected are screened out by interview, the seroprevalence among men has fallen from 1984 to 1992, whereas the

seroprevalence among women has remained static and was the same for men and women in 1992. North-eastern and Southern states again had the highest

seroprevalence.

Among heterosexually active females attending a sexually transmitted disease clinic who reported no intravenous drug use, the median prevalence was 1% with no increase since 1989.

Sentinel hospital surveys showed a male seroprevalence of 1.6%, and female seroprevalence of 0.4% with the characteristic high seroprevalence in the Northeast and South. Prevalence increased with age up to 35-44 years.

Blood donors in the US are now an interesting group to follow as exclusion risk groups have increased with a consequent fall in HIV seroprevalence. HIV prevalence among all female first-time donors was only 0.015%. These data indicate that heterosexual transmission of HIV to women from men who also acquired HIV heterosexually is very rare among populations represented by blood donors (Centers for Disease Control and Prevention, 1994).

Incidence is difficult to infer from these seroprevalence surveys. For women who have sex with men who have no risk factors for HIV, the incidence of HIV infection is low. For women who have sex with men at high risk due to intravenous drug use or bisexual behaviour incident infections occur especially among black minority groups in the North-east and Southern States. For intravenous drug using women who share needles, the incidence of HIV infection is high especially in the Northeast and South.

Women in Africa

HIV spread rapidly in many urban areas in sub-Saharan Africa through the 1980s. At least 80% of virus transmission is estimated to have occurred by heterosexual transmission. The first wave of transmission in many areas was in urban female prostitutes. In Nairobi in 1981 the prevalence among prostitutes was 4%. By 1985 61% of prostitutes were infected. Over the same period seroprevalence in men attending sexually transmitted disease clinics rose from 3% to 15%. By 1985 2% of women attending for antenatal care were infected. Extensive serosurveys in

countries notably Rwanda indicate that the highest incidence of infection is seen in young sexually active women with a peak age of 35 years. Women age 15-24 have a higher seroprevalence than men of the same age possibly reflecting that older men are sexually active with younger women who experience their first intercourse

at an earlier age. Seroprevalence as high as 40% has been recorded in sexually active women in some central African cities, others have much lower HIV

seroprevalence and rural areas usually have seroprevalence which is a fraction of that in the cities. Some rural areas have had steady fairly low seroprevalence over a 10 year period (Johnson, 1992).

Women in Asia

In Thailand the epidemic has been characterised by a rapid spread amongst injecting drug users and female prostitutes. In India, the epidemic mirrors the early stages of the epidemic in Africa, with rapid spread amongst urban prostitutes and emergence of infection amongst heterosexual STD clinic attenders (Johnson, -1992).

Women in the UK

While HIV prevalence in antenatal clinic attenders was lower in the UK than the US, geographic variability was evident with urban areas especially London having the highest prevalence. The results of the Unlinked-Anonymous antenatal HIV

serosurveillance programme from 1990 to 1992 showed no significant increase and a prevalence of 0.25% in London and 0.01% outside London (Anon., 1993). Of concern was evidence of the rising prevalence of HIV Infection in pregnant women in London from 0.05% in 1989 to 0.2% in 1991, by testing Guthrie card blood spots from neonates for maternal HIV-antibody (Ades etal., 1991). It was estimated that obstetricians were aware of matemal infection in only 1 in 5 of these pregnancies. In London, heterosexual female genitourinary medicine clinic attenders had

prevalence rates of 0.5% and 0.7% in 1990 and 1991, outside London 0.1%(1990) and 0.2%(1991). From the Praed Street Project 1986 onwards where a cohort of 148 female prostitutes were followed for a mean of 7.6 months, no HIV

séroconversions occurred. This study in the Paddington area of central London, where many foreigners come to live, and which is a known area for prostitution, would be a likely site for an epidemic of heterosexually transmitted HIV to these working girls. Two women were HIV-infected at the start of the study. One admitted

to having shared needles in the past. The other had a long time partner who was HiV-infected.

SCOTLAND

To 31/12/94, 604 AIDS cases had been reported to the Scottish Centre for Infection and Environmental Health (SCIEH), 496 male and 108 female (Scottish Centre for Infection and Environmental Health, 1995). Scotland with its population of about 5 million (9% of UK total) has 6% of the total UK AIDS cases. Forty-two percent were probably infected by sexual intercourse between men, 37% by injecting drug use (IDU), 5% by a blood or tissue factor, 1.8% mother to child and 13% heterosexually acquired. Reported HIV-1 infected persons totalled 2,209, 1662 male and 547 female, 10% of the UK total of reported HIV-1 infected persons. Twenty-nine percent were probably infected by sexual intercourse between men, 49% IDU, 5% by blood or tissue factor, 1% mother to child and 14% heterosexually.

Homosexual men

In 1981 the first AIDS cases were seen among homosexual men in Scotland. To 31/12/94, 636 HIV-infected persons had been reported where infection was probably acquired by sexual intercourse between men, 251 AIDS cases had been reported, of whom 194 had died(Scottish Centre for Infection and Environmental Health, 1995).

Intravenous drug users

Among intravenous drug users, infection with HIV probably took hold in Scotland during late 1983, in Edinburgh and Dundee(Peutherer etal., 1985, Urquhart etal.,

1987, Robertson etal., 1986), where prevalence reached over 50% in 1984. To 31/12/94, 1057 HIV-infected persons had been reported where infection was probably acquired by injecting drug use, 219 AIDS cases had been reported, of whom 155 had died(Scottish Centre for Infection and Environmental Health, 1995).

Blood and tissue products

During 1983 and 1984, prior to universal screening of blood donations in 1985, haemophiliacs became infected through use of virus contaminated blood products.

To 31/12/94,103 HIV-infected persons had been reported where infection was probably acquired by virus contaminated blood and tissue products, 33 AiDS cases had been reported, of whom 30 had died (Scottish Centre for Infection and

Environmentai Health, 1995).

Mother to child infections

Mother to child infection has been monitored by the Edinburgh Perinatal

Transmission Study(Mok etal., 1989). To 31/12/94, 24 HiV-infected chiidren had been reported where infection was probabiy acquired from mother during

pregnancy, delivery or after birth, 11 AiDS cases had been reported, of whom 5 had died(Scottish Centre for Infection and Environmentai Health, 1995).

Heterosexual transmission

Heterosexual transmission has been divided into three categories(Communicabie Diseases (Scotiand) Unit, 1992b):

First generation transmission refers to HIV infection acquired heterosexuaily through contact with an individuai from one of the established high risk groups (partner was a maie homosexual/bisexuai, an injecting drug user or had reguiariy received blood products).

Second generation transmission refers to heterosexual transmission occurring between sexual partners who do not fall within any of the high risk categories described above. The category second generation transmission is itseif further sub­ divided into heterosexual infection acquired abroad, possibly from an area where heterosexual transmission is the primary mode of transmission, and heterosexual transmission acquired within the UK (McKeganey, 1994).

To 31/12/94:106 reports (22 maie, 84 female) of "First generation transmission" HIV-infected persons had been made, 22 AIDS cases had been reported, of whom 12 had died(Scottish Centre for Infection and Environmental Health, 1995); 99 reports (69 male, 30 female) of "Second generation transmission exposed abroad"

HIV-infected persons had been made, 30 AIDS cases had been reported, of whom 16 had died; 47 reports (18 male, 29 female; 2.1% of all HIV reports) of "Second generation transmission exposed in the UK" HIV-infected persons had been made, 16 AIDS cases had been reported (2.6% of all AIDS cases), of whom 10 had died. Many (49) heterosexually transmitted HIV infections were still to be categorised and were "under investigation", 11 were unassignable after investigation.