6.3.3. HIV infection, sexually transmitted infections (STI) and blood-borne viral infections

 

HIV, other STI and blood-borne viral infections remain a priority in Europe. Even though available surveillance data have to be interpreted with caution, it is apparent that there have to be targeted approaches since each of the diseases has a different pattern in different countries.

 

There is a need to improve data collection for STI, e.g. through screening programmes where cost-effective, in order to determine the full picture of these diseases. Best practices for preventive campaigns and screening programmes could be exchanged between Member States.

 

6.3.3.1. Human papilloma virus infection

 

Infection with human papilloma virus (HPV) has received renewed interest through the introduction in 2006 of a vaccine, but is not a reportable disease in most Member States. Moreover, tere is a general lack of figures for prevalence or incidence. Properly designed epidemiological studies would help to define the profile of HPV strains most prevalent in the EU and its association with cancer of the uterine cervix, assisting with the design of adequate vaccination strategies.

 

6.3.3.2. HIV infection

 

HIV remains one of the most important communicable diseases in Europe. In western and central Europe, it is estimated that 720 000 people were living with HIV/AIDS at the end of 2005 and that about 15 000 individuals are becoming infected each year.

 

Effective antiretroviral combination therapies introduced in the mid-1990s and widely used in industrialised countries, have had a profound effect on the course of HIV infection, improving the quality of life and delaying the onset of AIDS and death in HIV-infected individuals, although intolerance to side effects and emergence of resistant strains remain cause for concern. AIDS surveillance is therefore no longer relevant to assess the spread and burden of HIV but is solely of historical interest. HIV reporting has become the key instrument for monitoring this epidemic in Europe.

 

 

Surveillance data on HIV/AIDS are collected by the EuroHIV surveillance network in the 53 countries of the WHO European Region, including the data from the EU and EEA/EFTA countries (Figure 6.2). The epidemic exhibits very different patterns in the different EU Member States in terms of magnitude, trends, and affected populations. In the EU15 countries, the epidemic is older and mature, with the highest rates found in Portugal. Among the other most affected countries, HIV data are not available in Italy and Spain, and have only become recently available in France. Where data are available, the number of new HIV diagnoses has been observed to have increased again in recent years in a number of countries, with a particularly marked increase seen in the UK and in the Netherlands.

 

 

Figure 6.2. HIV cases per million.

Source: ECDC, 2007

 

 

 

 

The epidemic in the new Member States is again diverse. In the Baltic States, the number of HIV diagnoses, which had been extremely low until then started to rise abruptly in the late 1990s, peaked in 2001 or 2002, and then declined. Estonia has, by far, the highest rate. In the other new Member States, although the number of new HIV diagnoses is increasing, the rise is slow and the epidemic remains at a low-level.

 

Much of the overall rise in the number of new HIV diagnoses in the EU is due to a steady increase in HIV infections diagnosed in people believed to have been infected through heterosexual contact: from 2 314 cases in 1996 to 6 386 in 2004. This increase is largely due to the rising number of diagnoses in people originating from high-prevalence countries outside Europe. The HIV diagnoses in men who have sex with men declined until around the year 2000 and since then has risen from 2 615 cases in 2001 to 4 151 in 2004. The number of newly diagnosed cases of HIV among injecting drug users (IDU) accounts for a low proportion of total cases, and has declined since 2001 (from 1 491 to 860 cases in 2004), although data are unavailable for Estonia, Italy, Spain and Portugal, where severe epidemics among IDU have been reported in the past.

 

In contrast to HIV diagnoses, AIDS incidence has been declining since 1995, when the AIDS incidence reached its peak in Europe. Similar trends have been observed in most EU countries. Exceptions are the Baltic States, where the HIV epidemic is much more recent and access to antiretroviral treatment likely to be less than in other countries.

 

Risk factors

 

In 2005, 28 044 HIV diagnoses were reported by 26 countries. Previous trends have generally continued throughout 2005, i.e. a rise in diagnoses in men who have sex with men and people infected through heterosexual contact. Heterosexual contact accounts for the largest proportion of HIV infections diagnosed overall and in most countries, but reflecting the diversity of the epidemic across Europe, men who have sex with men is the largest transmission group in several countries (Czech Republic, Denmark, Germany, Greece, Hungary, the Netherlands, Slovenia), and IDU the largest group in Latvia, Lithuania and Poland (no data by transmission available from Estonia). With 171 cases reported in 2005, mother-to-child transmission accounts for less than 1% of all new HIV diagnoses.

EuroHIV collects information on the country of origin of the case, rather than on the possible location of infection. Overall, nearly half (47%) of the newly diagnosed cases of HIV infection believed to have been acquired by heterosexual contact were among people originating from countries with more generalised epidemics, ranging from 17% in Portugal to 80% in Iceland. Data from several countries suggest that the majority of these people were infected in their country of origin, although transmission within the host EU country does occur.

 

Control tools and policies

 

It is estimated that 30% of the people living with HIV (PLHIV) in the EU are unaware of their infection. There is evidence to suggest that this group may be contributing disproportionately to the spread of the disease. Strong efforts must be made to increase testing uptake; thus, ECDC has started work to provide guidance on this issue for Member States. As for prevention, action should continue to target the populations at a higher risk. These are the high-incidence countries, where an integrated national effort is needed; men who have sex with men, where new methods are needed to implement the prevention messages; and migrants from high-risk countries, where research is needed on how to successfully approach these groups in society.

Immediately following diagnosis, PLHIV will need to receive life-long treatment, care and support. Currently 90% of infected people in the EU receive highly active anti-retroviral therapy (HAART). More work is needed to improve accessibility of this therapy to PLHIV. Counselling and support is of paramount importance to PLHIV and vulnerable populations at higher risk of infection and therefore best practices will have to be reviewed on how to improve these services in the EU.

 

6.3.3.3. Other sexually transmitted infections (STI)

This section addresses Chlamydia infections gonorrhoea and syphilis.

 

Chlamydia infection

 

Chlamydia infection, caused by the bacterium Chlamydia trachomatis, is often asymptomatic, but can lead to severe long-term complications such as ectopic (outside the uterus) pregnancy and infertility. In many European countries, Chlamydia infection is the most commonly reported STI, but in several countries the infection is not notifiable. Comparisons between reporting countries are also inhibited by differences in data collection. Screening studies in Europe have shown that between 1.7% and 17% of women with no symptoms are infected. Fourteen countries reported data for the full period (a further four reported for part of the period), and of those, quite dramatically increasing trends over the period 1995–2004 were observed in the Nordic countries, Belgium, the United Kingdom and Ireland, while the opposite was seen in Estonia, Latvia and Slovakia (Lithuania shows a stable trend). In 2005, 203 691 cases of Chlamydia infection were reported by 17 countries, with almost 96% of cases from (in descending order) UK, Sweden, Denmark and Norway. The highest incidence rate was reported by Iceland with 552.45 per 100 000, followed by Denmark with 441.29 per 100 000. Available data show that the disease is most common in the 15–24 age group and that infection is reported more often in women than in men (female to male ratio, 1.5:1).

 

A specific variant of the bacteria, lymphogranuloma venereum (LGV), gives a more severe systemic disease. LGV considered eradicated from Europe has again, since 2004, been noted in several large European cities among men who have sex with men.

 

 

Gonorrhoea

 

Gonorrhoea is caused by the bacterium Neisseria gonorrhoea. The extent of the infection can range from genital infection to a variety of systemic symptoms. In the last 10 years, the Baltic States (Estonia, Latvia and Lithuania) saw a steady decrease from levels of up to 200 cases per 100 000 per year in 1995, to below 40 per 100 000 per year in 2004. In the low-incidence countries in central Europe (Slovakia, Poland and Hungary) gonorrhoea incidences declined steadily to very low levels in 2001–03. In the Southern European countries, gonorrhoea has been decreasing since 1995, while in the UK, Belgium and Sweden the incidence appeared to decline during 1996–97 (and Norway in 1998), but has risen steadily since then (figure 6.3). In 2005, a total of 27 537 cases were reported by 22 countries. The highest incidence rate was observed in the UK (33.98 per 100 000), followed by Latvia (30.09 per 100 000) and the lowest in Luxembourg (0.22 per 100 000), followed by Spain and Portugal (both with 0.42 per 100 000). However, different surveillance systems operate in these countries making direct comparisons inappropriate. The highest incidence rates were observed in the 15–24 age group , while the incidence was 4.5 times higher in men than in women.

 

Figure 6.3. Trends of Gonorrhoea within the EU, 1995 - 2004

 

Syphilis

 

Syphilis significantly declined after World War II thanks to the widespread use of penicillin. However, a considerable resurgence of syphilis occurred in the late 1980s in the industrialised countries.

In the last 10 years, the incidence decreased steadily after 1996 from just under 3.5 to 2.2 per 100 000 per year in 2000, but has been rising steadily since then reaching 3.1 per 100 000 per year in 2004, mainly due to outbreaks in large cities involving men who have sex with men. In the Baltic States (Estonia, Latvia and Lithuania) where syphilis incidence was very high in the early 1990s (over 60 cases per 100 000 per year in 1995), a sharp decrease in incidence was observed from 1996 to 2004. In some central European countries (Slovakia, Slovenia and Poland) syphilis incidence remained below 10 cases per 100 000 per year, with an overall decreasing trend. In 2005, 12 945 syphilis cases were reported by 24 countries. The highest incidence rates were still recorded in Latvia (19.21 per 100 000), Lithuania (8.61 per 100 000) and Estonia (8.24 per 100 000), with the 25–44 age group as the most affected. Incidence was higher in men than in women (male to female ratio, 4.4:1).

 

Neonatal syphilis is still unacceptably common in the EU. It is a potentially eradicable form of syphilis within the next decade, this depending essentially on the adequate performance of and coverage with antenatal care services and supervised labour care of pregnant women.

 

 

6.3.3.4. Blood-borne viral infections

This section addresses hepatitis B and C.

 

Hepatitis B

 

Hepatitis B is an infection of the liver caused by hepatitis B virus (HBV). HBV can result in either asymptomatic or symptomatic infection. As for other types of acute viral hepatitis, acute infection may vary from mild to severe symptoms, and HBV infection in children usually goes with few or no symptoms. Conversely, the fatality rate can reach 2% in the elderly. A significant proportion of those chronically infected can develop liver cirrhosis (25%) or cancer (5%), and patients with chronic infection serve as a reservoir for continuing HBV transmission. Hepatitis B has to be considered increasingly as an STI, although there is evidence that common practices (tattooing, beauty treatments, etc.) are still important in spreading HBV infection. The infection remains concentrated in migrants from high-prevalence countries and in people whose activities place them at high risk of becoming infected, such as IDU and people with multiple sex partners.

 

Almost 180 000 cases of Hepatitis B were reported in Europe during the last 10 years, with an overall decreasing trend from 6.6 to 2.6 cases per 100 000 per year over the period. However, this pattern is not consistent across Europe and some countries have reported an increasing incidence since the late 1990s. Of the 6 977 cases reported in 2005 by 26 countries, the highest incidence rates were reported by Iceland (11.24 per 100 000), followed by Latvia (7.37 per 100 000). Incidence was higher in men than women (male to female ratio, 2.3:1).

 

 

HBV vaccination is currently the most effective way to prevent HBV infection. Most of the EU Member States have included hepatitis B vaccine in their national vaccination programmes. Even before this could have had any noticeable effect, incidence of acute hepatitis B infection had been declining slowly in most countries.

 

Hepatitis C

 

Hepatitis C is the most common type of viral hepatitis in the E.U.

 

Hepatitis C is caused by the hepatitis C virus (HCV), for which no vaccine is available. Up to 90% of HCV infections are asymptomatic. A high proportion of those infected develops a chronic infection and many of those go on to develop liver cirrhosis or cancer. Injecting drug use is the dominant mode of transmission and studies show that IDU are generally infected within one year of their first injection. Sexual transmission seems to be infrequent. After 1994 transmission via blood transfusion and use of plasma-derived products became rare, as routine HCV tests became more available.

After a relatively stable period during 1995–2000, the incidence in Europe has increased steadily from 7.0 per 100 000 per year in 2001, to 7.9 per 100 000 per year in 2004, but this increase may possibly be a surveillance artefact. In 2005, more than 29 000 hepatitis C cases were reported by 24 countries. The highest incidence rates per 100 000 per year were reported by Ireland (34.99), Sweden (28.96), and the UK (17.54). However, due to the nature of the disease (mainly chronic, asymptomatic infections) and the relatively recent introduction of HCV infection into the list of diseases under surveillance at national level, the currently available data do not permit a clear picture of the HCV trend in Europe.