This clinical-based report presents the burden of HAV and other blood-borne infections in a population of hemophiliacs, a high-risk population in south Khorasan province, Iran that had not been studied previously. We conducted a cross-sectional study of recent anti-HAV seroprevalence to establish effective preventative measures for HAV infection in hemophiliacs.
The overall prevalence of hepatitis A infection in the hemophilic population was 77.8%, which is in contrast with previous observations reported in Egypt (
12). The rate of prevalence, however, varies widely in different parts of the world (
12,
17). In a study on 133 hemophilic cases, Molina found that it was 43% among Spanish hemophilic patients (
18). Mauser-Bunschoten in his study in the Netherlands showed that the anti-HAV prevalence in 197 hemophiliacs (treated with clotting factor concentrates produced from large plasma pools) was 20%, and in 144 patients (treated with small pool cryoprecipitate) it was 13% (
19), while it was 22.4% in Hayashi’s study in Japan (
20). The level of hygiene in different communities could be one of the most important reasons for these variations. Poor hygiene, poor water sanitation, and family crowding, which increase the chance of close contact with the virus, are several reasons for the increased prevalence of the infection. Although in a cross-sectional study conducted among 1- to 15-year-old children, no difference in the seroprevalence of hepatitis A related to age groups, mean age, sex, and family size was observed (
21), in most multivariate analyses, region, age group, marriage, referral date, and level of parental education were associated with hepatitis A virus seropositivity (
17,
22-
29).
The outcome of the positivity rate for anti-HAV concerning region (51.4% in urban areas and 91.5% in rural areas) is completely in favor of the findings of Taghavi and his colleagues in Shiraz showing the high frequency of HAV-positive individuals living in rural areas (95.9% of rural people in comparison with 85.1% of the urban population) (
28). In another study, the overall seroprevalence of HAV in the general population of three provinces of Iran (Tehran, Golestan and Hormozgan) was 86%, with no variation between the two genders (
22). The prevalence in younger subjects and in urban populations was under 70% (
22), while in another province of Iran (Kashan) only 3.9% of children between 1 and 15 years old were reported to be seropositive (
21).
Patients’ age is the other contributory factor. There was a direct relationship between seroprevalence and age, as a rise in age caused an attendant increase in seroprevalence. The other point worth noting was the significant difference between the age groups (P < 0.001). The infection rate in subjects over 19 years old was 77.1%, while it was only 22.9% in those younger than 19. In Hayashi’s study, the infection incidence in the age range of 10 – 19 years was 21.4 %, and 30.8% of hemophilic patients were 40 - 49 years old (
20). In Chambost’s investigation, 20% of people were 30 to 35 years old, and almost 49% of infected patients were over 50 years (
28).
Some reports have indicated an increasing rate of acute HAV infection in adults in Iran in recent years (
23). A serosurvey in Tehran in the late 1970s found that more than 90% of 10 years old had immunity against HAV (
24). Studies in the 2000s show a much lower seroprevalence in the majority of children and teenagers, while they still remain susceptible to hepatitis A infection (
25), which can be one of causes of high seroprevalence. The other underlying cause is the high anti-HAV seroprevalence rate in the Middle East (
26), which could increase the chance of exposure to the virus, leading to high seroprevalence in Iran.
Hepatitis C and HTLV-1 positivity were reported among 20.4 and 2.8% of our participants, respectively, similar to recent studies in Iran and the United States, where blood transfusion was reported as a common factor of HCV (
30-
32). The prevalence of hepatitis C infection in hemophilia patients in a study in Germany was 98.6% (
33); it has also been reported to be 54.5% in India (
34) and 96.97% (Mzandaran province) (
30) and 60.2% (Tehran p rovince) (
35) in Iran. The seroprevalence of HCV and HBs-Ag, as the Zahedan hemophilia center reported, was 29.6% and 4.9%, respectively, in hemophilic patients (
36), which is more prevalent than our study.
However, as the results of this study indicate, there were no HIV- or hepatitis B-infected patients among the participants. The prevalence of hepatitis B infection in Borhany’s study conducted in Karachi was reported to be 1.73% of hemophilic people (
37); however, in another study in Iran, no association between HBV infection and blood transfusion, as a main route of infection in hemophiliacs, was reported (
38).
One possible explanation for the inconsistency between the previous results and the present findings is that most of our hemophiliac patients were living in rural areas and did not have access to coagulation factors in these areas; therefore, they have received cryoprecipitate instead of coagulation factors, which reduced the likelihood of blood-disease transmission. Cryoprecipitate is prepared from the blood of local blood donors, and the prevalence of blood-borne diseases such as AIDS, HCV, and HBV infection is lower in these areas. Therefore, the prevalence of infection with hepatitis C, hepatitis B, and HIV in our study was lower than previous studies. These findings support previous results from a study in south Khorasan (
39).
We attempted to determine whether vaccination against hepatitis A in hemophilic patients in south Khorasan is necessary. The results show that more than 40% of the hemophilic patients in our study under 20 years of age have no immunity against hepatitis A, and 23% of hepatitis C patients have not had a hepatitis A co-infection yet. Since hepatitis A can show a fulminant course in hepatitis C patients, vaccination against hepatitis A seems necessary in hemophilic patients in the region. Moreover, further studies on hemophilic patients in other regions of Iran seem necessary to determine their immunity status against hepatitis A.