Eurosurveillance

ECDC

The Epidemiology of HIV Infection in Lithuania, 1988-2005

 Rediger
  Published: 15.10.07 Updated: 15.10.2007 11:57:15

S. Caplinskas,  O. Strujeva, V. Uzdaviniene. Lithuanian AIDS Centre, Vilnius, Lithuania

Introduction

The Republic of Lithuania is situated in Eastern Europe and has inland borders with Latvia in the north, Belarus in the west and south, and Poland and the Kaliningrad region of the Russian Federation in the south-west. Lithuania has a population of 3.4 million. The largest cities by population are Vilnius, the capital (542 300), Kaunas (378 900), Klaipeda (193 000), Siauliai (133 900), and Panevezys (119 700) (1)
Since independence in the early 1990s, Lithuania has experienced major changes in political, economic, and social structure. Economic dislocation and the disruption of personal, domestic and inter-community networks have contributed to epidemics of substance abuse, high-risk sexual behaviour, and infectious diseases including tuberculosis, viral hepatitis, HIV infection and sexually transmitted infections. Although Lithuania still appears to have a low prevalence of HIV, it is bordered by some of the most affected European countries (2, 3).
The prevalence of HIV in Lithuania increased from 1.45 per 100 000 in 1996 to 29.4 in 2005. HIV incidence has also gradually increased; in 1996 the incidence of HIV infection was 0.33 per 100 000 population and increased to 3.51 in 2005.
This article provides an overview of the current epidemiological situation and trends of HIV infection in Lithuania.

Methods

This review is based on a retrospective analysis of the national HIV surveillance database in Lithuania. The systematic surveillance of HIV infection in Lithuania was introduced in 1987 (4). The Lithuanian AIDS Centre (LAC) is the main centre for surveillance, prevention, clinical and referral diagnostic centre for HIV infection (4). The initial network included screening programs for pregnant women and other general population groups in 1988-1993. Since 1993 certain changes in testing policy have been implemented focussing on high risk populations and establishing especially active serological surveillance in prison settings (4, 5).
Communicable diseases including HIV infection are regulated on a basis of the following legal acts: Law on Human Communicable Diseases Prevention and Control of the Republic of Lithuania, and Procedure of Epidemiological Surveillance of HIV infection and HIV disease in Individual and Public Health Care Institutions approved by the Order of the Health Minister of the Republic of Lithuania No V-117, 25th February 2003. Physicians at health care institutions are required to report every new HIV infection according to the statistical form “Protocol of epidemiological testing of sexually transmitted infection, HIV infection and HIV disease, F. No 151-9/a” and submit the form to the territorial public health centres that subsequently are required to submit the data to the Lithuanian AIDS Centre. Aggregated data must be submitted to the National Registry of Infectious Diseases.

Results and discussion

The first HIV case in Lithuania was reported in 1988. From 1988 to January 1, 2006 a cumulative total of 1100 (29.41 per 100,000 population) HIV infections were registered in Lithuania.  Of these 96 have developed AIDS and 99 people living with HIV or AIDS have died (Fig 1) (6, 7). However, the actual number of HIV cases may be higher than reported. International agencies estimated that 3300 people were living with HIV in Lithuania at the end of 2005 (2).
The HIV epidemic in Lithuania appears to have passed through two phases. The first phase ran from the end of the 1980s to the year 2002 (8).  This was a silent phase with only a few cases that were primarily acquired abroad (9). Up to the end of 2001, the cumulative number of HIV cases was 328. In 2002, however, during several months of intensive screening at the Alytus Correctional Facility (prison) 299 new HIV cases were identified. By the end of 2003 the number of identified HIV cases reached 845. This increase was attributed to an outbreak of HIV infection among the inmates sharing needles at the Alytus Correctional Facility (10).

Figure 1. Number of HIV/AIDS cases registered per year in Lithuania, 1988-2005.

 

 

 

 

 

 

 

HIV by transmission routes

Up to 1997, HIV was predominantly transmitted by heterosexual and homosexual intercourse: in 1989-1993 the virus spread mostly among men having sex with men (MSM), in 1993-1996 heterosexual transmission prevailed and was predominantly detected among sailors infected abroad. From 1997 onwards HIV has mainly been spread via the sharing of contaminated needles among intravenous drug users (IDU). This mode of transmission accounts for 70-77% of all new cases annually exept in 2002 when 95% of all new infections were attributed to needle sharing as reflected in an outbreak at the Alytus Correctional Facility (10).
In total numbers, 866 (78.7%) cases have been infected through illicit drug injection, 114 (10.4%) through sex between men and women and 70 (6.4%) through sex between men. For 50 (4.5%) cases, the transmission route remains unknown (Fig. 2).

Figure  2.  Trends of HIV transmission mode in Lithuania, 1988-2005.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
HIV transmission through sexual contacts

Homosexual transmission

WHO and UNAIDS experts participating in a workshop that took place during 2003 estimated the number of MSM in Lithuania to be from 17 000 up to 44 000 (11). The first HIV positive cases in Lithuania were diagnosed in the MSM community in 1989. We believe that the virus entered this community in 1980-1983. There were seven HIV cases registered in 1990. These cases were traced mostly by partner notification.
In 1989-1993, the virus spread among MSM. During later years, only a few cases of HIV infection among MSM have been reported. Up to 1997, 20 HIV cases of HIV among MSM were identified. From 1996, the number of new cases reported among MSM has been low, 4 and 3 cases in 2004 and 2005, respectively, and stable. Sentinel surveillance among MSM performed by the Lithuanian AIDS Centre detected 2 cases of HIV among 242 MSM tested in 2003 and 0 cases among 79 tested in 2004 and 34 MSM tested in 2005.

Heterosexual transmission

The first case of heterosexual HIV transmission was reported in Lithuania in 1988. In 1993-1996 heterosexual transmission prevailed and HIV infection was predominantly registered among seamen who acquired the virus in Africa and the Far East. During 1988-1996, 50% of all new cases were due to heterosexual transmission while the number dropped to only 8% between 1996-2005. In recent years, the proportion of cases resulting from heterosexual transmission has steadily increased from 9% in 2001 to 18% in 2004, and 17% in 2005.
According to the data provided by the Lithuanian AIDS Centre, 20 women with HIV are or have been sex workers. It is possible that HIV might be spread into general population via sex workers bridging different groups in the population. Sentinel surveillance of sex workers in the Women Health Unit at the Lithuanian AIDS Centre detected no HIV infection among 89 tested in 2003, 86 tested in 2004 and 111 tested in 2005.

HIV transmission among intravenous drug users (IDU)

The first HIV-positive IDU in Lithuania was diagnosed in 1994. Two years later 4 HIV-positive IDUs were reported in the Klaipeda harbour area. Starting from 1997, HIV has been mainly spread via sharing contaminated needles within the IDU community. In 1997, IDUs accounted for 70 % of all registered cases of HIV. Annually, this mode of transmission accounts for 70-77% of all new cases of HIV infection in Lithuania (10). The estimated number of IDUs in Lithuania is more than 7000, but accurate data are still lacking due to inadequate resources needed to perform the necessary investigations (12).
In 1991 the Lithuanian AIDS Centre initiated the first and only syringe exchange programme in the country. The Drug User’s Social and Psychological Rehabilitation Community of the Lithuanian AIDS Centre was established in January 1992 (4). Additional needle and syringe exchange programmes (NEP) were initiated in 1997 in Vilnius (4). In 1998, the Lithuanian AIDS Centre opened a ‘low threshold’ consulting room to promote counselling and similar services among IDUs and to reduce the transmission of HIV and other STIs transmission among IDU and their sexual partners.  During 1998-2005 a total of 2408 IDUs, clients at the Low Threshold Site for drug users at the Lithuanian AIDS Centre, were surveyed and 90 HIV cases identified (3.7%).
A seroprevalence study conducted by the “Blue Bus” mobile syringe exchange programme that has tested 681 people by a rapid blood-based dot-blot test revealed 22 HIV (3%) and 557 (82%) HCV cases. An exceptionally high rate of past needle sharing or of contaminated drug mixture injection was reported in 2005 (13, 14). Early prevention measures addressing the needs of the IDU population helped to keep the spread of HIV in this risk group low. At present, the results of various HIV seroprevalence studies indicate an HIV prevalence of up to 5% among IDUs.

HIV infection by gender

During the entire period, 1044 HIV cases among males and 156 among females were registered. The first woman with HIV infection was identified in 1990. Since 2000, the number of HIV cases in women has increased, and the male/female HIV ratio has decreased from 12:1 in 2002, 7:1 in 2003, 5:1 in 2004 and 3:1 in 2005 (15) (Table 1). The majority of females with HIV are on average 31 years of age and have been infected through intravenous drug use (68%). The number of heterosexual transmission cases among females has also increased (Fig.3).

Table 1. Number of HIV cases registered per year by gender in Lithuania, 1988-2005

 

Gender / Пол

Years / Годы

1988-1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

Female / Женщины

1

3

9

8

15

23

8

16

21

30

Male / Мужчины

51

28

43

58

50

49

389

94

114

90

Figure 3. Number of newly identified HIV cases infected heterosexually, by gender in Lithuania, 1988-2005.

 

 

 

 

 

 

 

 

Mother to child transmission

The increase in HIV infection among women in Lithuania could potentially influence mother-to-child transmission. The majority of women with HIV of child-bearing age and it is well known that a woman with HIV can infect the foetus during pregnancy, during delivery and through breast-feeding. (16). Perinatal HIV prevention is regulated by legislative acts of the Ministry of Health. These legislative acts recommend that HIV counselling and testing is provided to all pregnant women during the first and third trimesters of pregnancy (18). HIV testing is available for all pregnant women and provided free-of-charge due to the risk of perinatal transmission.
The first HIV positive woman in Lithuania delivered a baby in 2002. To date, 17 HIV-positive women have delivered babies and all of the infants were HIV negative (17). By antenatal HIV screening the HIV prevalence among pregnant women was 0.03 % in 2004 and 0.05% in 2005 (15, 19).

Table 2. Number of HIV infection cases by age in Lithuania, 1988-2005

Age / Возраст

Males / Мужчины

Females / Женщины

Total / Всего

15 – 19

41

9

50

20 – 24

159

31

190

25 – 29

254

30

284

30 – 39

327

44

371

40 – 49

128

12

140

50 – 59

32

3

35

60 - >

9

3

12

unknown / неизвестно

16

2

18


HIV infection by age groups

HIV infection has primarily predominated among persons aged 25-29 (26 %) and 30-34 (18%) years, while 77 % of cases were identified in the age group of 20-39 years. (Table 2). The youngest patient in Lithuania was 15 and the oldest 68 years of age at the time of HIV diagnosis. The average age differs according to mode of transmission. Among persons infected via sexual intercourse the average age is 37 years (SE=0.89) and among IDU is 30 years (SE=0.26).

Geographical distribution

HIV infection has been reported from the majority of Lithuanian administrative units. The largest number of HIV cases has been registered in Klaipeda, the main Lithuanian harbour city, with 29 % of all cases in Lithuania (Fig. 4). The highest HIV prevalence rate, 154 per 100,000 population, at the end of 2005 was reported in Klaipeda city followed by Mazeikiai (59), Kalvarija (37), Druskininkai city (36), Siauliai city (29), Vilnius city (25), Siauliai district (24), Palanga city (23), Marijampole district (13) and Kaunas city (10)  (7).
There were 49 HIV cases reported among foreigners including Russians (14), Latvian (16), Belarusian (4), Estonian (2) and one each from France, Denmark, Spain, Poland, Ukraine, Uzbekistan, Thailand and Vietnam. The nationality was unknown for 5 cases.

Figure 4. Cumulative number of diagnosed HIV cases in Lithuania regions, 1988-2005.

 

 

 

 

 

 

 

 

 

AIDS cases

AIDS was first diagnosed in Lithuania in a man during 1988.  Eleven years later, in 1999, the first woman in Lithuania was diagnosed with AIDS.  The overall AIDS incidence rate has been slowly increasing during the past 12 years from 0.03 per 100 000 in 1990 to 0.29 per 100 000 in 2005.
From introduction of the HIV registry, AIDS has been diagnosed in 96 persons (Table 3). There have been 41 AIDS-related deaths. Of all registered AIDS cases, 56  are MSM, 24 heterosexuals, and only 12% might be attributed to IDU. The mode of transmission is unknown in 8% of all cases. AIDS was diagnosed simultaneously with the first positive HIV test result in 4% of all cases. Identifying HIV infection at an early stage of disease is one of the advantages of the national HIV surveillance system.

Table 3.  Number of AIDS cases and PLWHA deaths in Lithuania, 1988-2005

 

Males / Мужчины

Females / Женщины

IDU / ПИН

Total / Всего

AIDS cases / Случаи СПИД

84

12

17

96

Number of deaths among people living with HIV/AIDS (PLWHA) / Число случаев смерти у людей, живущих с ВИЧ/СПИД (ЛЖВС)

9

12

54

99

 

 

 

 

 

Conclusions

Lithuania is a country with low HIV prevalence and the epidemic is similar to that in other Eastern and Central European countries. The first cases were detected among MSM, then among IDUs and, recently, infection has been spreading more rapidly among heterosexuals. The prevailing mode of transmission is still injecting drug use among men. The prevalence of HIV infection is highest in the seaport and capital cities. The HIV epidemic peaked in Lithuania during the year 2002 due to an HIV outbreak in one correctional facility and, until recently, the incidence rate declined.  During 1996-2005 the incidence rate has increased from 0.33 per 100 000 to 3.51 per 100 000. Though HIV infection among the male IDUs prevails, a rise in new cases among women is being observed. To date, no cases of perinatal HIV transmission have been reported. 77% of cases were identified in the age group 20-39 years.

References

  1. Department of Statistics to the Government of the Republic of Lithuania. www.stat.gov.lt
  2. UNAIDS/WHO "AIDS Epidemic Update. December 2006; 396: 501-541.
  3. HIV/AIDS Surveillance in Europe. European Centre for the Epidemiological Monitoring of HIV/AIDS, WHO and UNAIDS Collaborating Centre on HIV/AIDS. Mid-year report 2005.72.2006; 6-8.
  4. Caplinskas S. Lithuania response to HIV/AIDS – first 15 years. Vilnius.2004; 5-9.
  5. Caplinskas S. ŽIV infekcija, AIDS ir visuomenės sveikata.Vilnius. 2004; 29-33.
  6. Lithuanian Health Information Centre. www.lsic.lt
  7. Ministry of health of the Republic of Lithuania. Lithuanian Health Information Centre. “Health statistics of Lithuania 2005. Vilnius 2006; ISSN 1392-8155
  8. Caplinskas S. Epidemiology of HIV/AIDS in Lithuania in 1988-2001:review of present situation and prognosis of HIV transmission trends. Medicina, 2004; 40 (2): 161-168.
  9. Likatavičius G., Caplinskas S., Rakickienė J. HIV/AIDS epidemiology in Lithuania. Acta medica Lithuanica. –ISSN 1392-0138.- 2001; Supplement 6: 17-24.
  10. Caplinskas S., Likatavičius G. Recept sharp rise in registered HIV infections in Lithuania. Eurosurveillance Weekly 2002;6(26):27/06/2002
  11. UNDP. Reversing the epidemic. Facts and Policy options. Bratislava, 2004; 25 - 36.
  12. Vilnius Center for Addictive Disorders. www.vplc.lt
  13. European Monitoring Centre for Drugs and Drug Addiction. www.emcdda.europa.eu
  14. Drug control department under the goverment of the Republic of Lithuania. Annual report 2005. Vilnius 2006; 9-15.
  15. Strujeva O., Uzdaviniene V., Caplinskas S. Characteristics of HIV transmission in women in Lithuania. 7 th Nordic-Baltic congress on infectious diseases „Current challenges and new opportunities“: final programme, abstracts, Riga, September 18-20, 2006; 33.
  16. CDC. Revised Guidelines for HIV Counseling, Testing, and Referral and Revised Recommendations for HIV Screening of Pregnant Women. MMWR 2001; 50:59 – 86.
  17. Uzdaviniene V., Strujeva O., Caplinskas S. Perinatal HIV prophylaxis in Lithuania. 7th Nordic-Baltic congress on infectious diseases „Current challenges and new opportunities“: final programme, abstracts, Riga, September 18-20, 2006; 32-33.
  18. Lietuvos Respublikos sveikatos apsaugos ministro 1999 m. kovo 15 d. įsakymo Nr.117”Dėl nėščiųjų, gimdyvių ir naujagimių sveikatos priežiūros tvarkos patvirtinimo” Valstybės Žinios, 1999.03.26, Nr.: 28, Publ. Nr.: 811 , Lietuvos Respublikos sveikatos apsaugos ministro 2004 m. vasario 20 d. įsakymo Nr. V- 79 redakcija. Žin., 2004; Nr. 32:1030.
  19. Mandelbrot L, Le Chenadec J, Berrebi A et al. Perinatal HIV–1 transmission: interaction between zidovudine prophylaxis and mode of delivery in the French perinatal cohort JAMA 1998; 280:55 – 60.




 


 Print