Seroprevalence of human immunodefi ciency virus in Nepalese blood donors: A study from three regional blood transfusion services

The first case of acquired immune deficiency syndrome (AIDS) in Nepal was reported in 1988.[1] As of 15th December 2007 National Center for AIDS and STD Control (NCASC) has offi cially confi rmed 10,546 HIV positive cases in Nepal which include 1,610 confi rmed cases of AIDS. It has also reported that among the 10,546 confi rmed cases of HIV, 24 cases (0.23 %) are associated with blood transfusion or organ/tissue reception.[2] UNAIDS has estimated the adult (15-49 years) HIV prevalence rate of 0.5% by the end of 2005 in general population of Nepal, whereas the number of people living with HIV in the same time has been estimated to be 74,000.[3]


Introduction Introduction
The first case of acquired immune deficiency syndrome (AIDS) in Nepal was reported in 1988. [1] As of 15 th December 2007 National Center for AIDS and STD Control (NCASC) has offi cially confi rmed 10,546 HIV positive cases in Nepal which include 1,610 confi rmed cases of AIDS. It has also reported that among the 10,546 confi rmed cases of HIV, 24 cases (0.23 %) are associated with blood transfusion or organ/tissue reception. [2] UNAIDS has estimated the adult (15-49 years) HIV prevalence rate of 0.5% by the end of 2005 in general population of Nepal, whereas the number of people living with HIV in the same time has been estimated to be 74,000. [3] Globally, a total of 33.2 million (30.6-36.1 million) people were living with HIV in 2007, 6.3 million less than in 2006. [4] A total of 39.5 million (34.1-47.1 million) people were living with HIV in 2006, 2.6 million more than in 2004. In 2006 it has been reported that, in many part of the world, new HIV infections are heavily concentrated among young people. [5] Over the last few years HIV/AIDS epidemic in Nepal has gained ground and Nepal has progressed from a low prevalence country to one with so called concentrated epidemic in certain subgroups of the population. A situation analysis study of HIV/AIDS conducted in 2000 has identifi ed the young people, Mobile populations, Female Sex Workers, Men who have sex with men, Injecting drug users, and Children as the most vulnerable to HIV/AIDS in Nepal. [6] The likelihood of HIV infection occurring in recipients of HIV positive blood is close to 100% and the prevalence of HIV among recipients of blood or blood products before the screening of HIV in blood units was quite high. In countries where screening of blood for HIV has been instituted, the risk of HIV transmission through screened blood has been estimated to be 1/36000-1/225000 units transfused. This residual risk is reported to be due to antibody negative infected donors in the window period. [7] Present study was aimed to reveal the seroprevalence rate and compare the seroprevalence of HIV among blood donors from the three regional blood transfusion services situated in three developmental regions of Nepal.

Materials and Methods Materials and Methods
This was a descriptive cross-sectional study conducted in three regional blood transfusion services of Nepal over a period of one year from July 2006 -June 2007. Donors were selected if they fulfi lled all the criteria to be eligible for donation as described by the Nepal Red Cross Society. All blood donors donating blood in respective blood transfusion services or in mobile camps were included in the study. Before drawing the blood, each donor was requested to fi ll a blood donors form. A total of 16,557 blood donors viz. 5,351 donors in Morang, 5,211 in Banke, 5,995 in Kaski were subjected for routine mandatory screening for Anti HIV 1 and 2 antibodies by an EIA based rapid test according the standard protocol described by respective company (HIV TRI-DOT, J. Mitra and Co, New Delhi, India). Initially reactive sera were reconfi rmed by repeat testing. Blood samples were tested anonymously and confi dentiality was maintained as described by Nepal Red Cross Society, Blood Transfusion Service. The signifi cance of difference in seroprevalence of HIV among the three regional blood transfusion services was tested by 'Fisher's exact test' using the software "Winpepi ver 3.8"

Results Results
In the Morang (Biratnagar) Blood Transfusion Service, a total of 5,351 donors were screened in which 84.8% (4,537/5,351) were males and 15.2% (814/5,351) were females [ Figure 1]. Among them only a single male donor was found seropositive giving the seroprevalence of 0.019% (1/5,351) [ Table 1]. In the Banke (Nepalgunj) Blood Transfusion service, a total of 5,211 donors were screened in which 91.5% (4,766/5,211) were males and 8.5% were females [ Figure 1]. Among them fi ve donors were found seropositive giving the seroprevalence of 0.095% (5/5,211). All the seropositive donors were males with age ranging from 24-39 years [ Table 1].
The difference in seroprevalence observed among the three regional blood transfusion services was not statistically signifi cant (P = 0.2096, Fisher's exact test).

Discussion Discussion
This study revealed a low seroprevalence of HIV among the three regional blood transfusion services of Nepal compared with the seropositivity rate described for Kathmandu Valley (0.16%). [8] This difference might be due to the use of different test kits for screening, centralized urban setting of Kathmandu Valley or a refl ection of actual epidemic in their targeted blood donor population. Similarly, Chander et al, has reported a 3.2% seroprevalence of HIV in patients attending teaching hospital from Bhairahava, Western Nepal which is much higher than the result of present study . [9] Particular vulnerability to HIV seropositivity was observed among male donors (100%) than among female donors which was also in accordance with the data of Chander et al. This might be due to the lower number of female donors in both of the studies. Our study revealed a quite low seroprevalence than described for general Nepalese population (0.5%) [3] and healthy Nepalese males (1.6%). [10] Such a signifi cant difference might be due to stringent donor selection procedures implemented by Blood Transfusion Services. Similar lower seroprevalence among blood donors has been reported by Gupta et al, [11] from Ludhiana of India (0.084%), Ayala Gaylan et al, [12] from Mexico (0.02%), Rahaman et al, [13] from Pakistan (0.001%), Kakepoto et al, [14] from Pakistan (0.007%). This study revealed that the seroprevalence was not signifi cantly different from one blood transfusion service to another despite the wide difference in geography and other factors associated with geographic variation. This study suggests that the policy applied by Nepal Red Cross Society, Blood Transfusion Service for recruiting and collecting the Safe blood donors is working equally well for all the regional blood transfusion services in Nepal.