SEROLOGICAL STATUS OF HEPATITIS B VIRUS INFECTION AMONG MONKS AND NOVICES AT BUDDHIST MONASTERIES IN THREE TOWNSHIPS, YANGON

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1 SEROLOGICAL STATUS OF HEPATITIS B VIRUS INFECTION AMONG MONKS AND NOVICES AT BUDDHIST MONASTERIES IN THREE TOWNSHIPS, YANGON Moe Pwint 1, Aye Marlar Win 1, Wah Win Htike 1, Khine Khine Su 2, Wai Wai Min 1 1 Department of Microbiology, University of Medicine 1, Yangon 2 Department of Microbiology, Defence Services Medical Academy 1

2 INTRODUCTION Infection with hepatitis B virus remains a global public health problem with significant morbidity and mortality HBV infection was estimated that 257 million people worldwide are living with chronic HBV infection in 2015 Of all these, 22 million knew their diagnosis Many people are diagnosed only when they already have advanced liver disease (World Health Organization, 2017) 2

3 HBV endemicity Based on prevalence of HBsAg in general population, HBV carriers rates of countries are classified as High endemicity 8% intermediate endemicity 2-7% low endemicity < 2% (Murray et al., 2016) 3

4 In US, Among general population for the periods of 1999 to 2006 HBsAg- 0.27% (80/29828) Anti-HBc- 4.7% (1431/29828) 4

5 In India, 200 blood donors were screened HBsAg- 3.5% (7/200) Anti-HBc- 10.9% (21/193) Anti-HBs- 3% (6/193) by ELISA (Lavanya et al., 2012) According to these findings, absence of HBsAg in the blood of apparently healthy individuals may not be sufficient to ensure lack of circulating hepatitis B virus (Ponde et al., 2010) 5

6 Myanmar, Myanmar is one of the HBV endemic countries with the carrier rates of 6.5% (361/5547) in general population In Yangon, prevalence of HBV infection was 12.3% (37/301) by rapid test kit among general population (Aye-Aye-Lwin et al., 2017) 6

7 Spread of HBV occurs through - parenteral - sexual - vertical - horizontal transmission via close contact In endemic regions important modes of transmission are - vertical - contact associated transmission 7

8 HBV infection via horizontal transmission is associated with various factors - Viral loads in body fluids - stage of infection - viral activity - host immune response (Komatsu et al., 2016) 8

9 Diagnosis of HBV infection is made from clinical manifestation and serology HBsAg is commonly used in screening of hepatitis B infection But hepatitis B infection may persist in the absence of circulating HBsAg and it may be due to persistence of HBV genomes in the hepatocytes Such condition is referred as occult B infection (Miller, 2016)

10 Occult B infection classified as seropositive and seronegative Seropositive occult B infection is characterized by serum negative HBsAg and positive anti-hbc, with or without detectable anti-hbs Seronegative occult B infection is characterized by the negative for all serological markers (Raimondo et al., 2008) 10

11 Occult hepatitis B infection can be found in individuals with resolving hepatitis B infection and HBV carriers whom HBsAg is not detectable due to presence of escape mutants (Raimondo et al., 2007; Said, 2011) Anti-HBc is an important marker of HBV infection during window period and is also a surrogate marker of seropositive occult B infection if highly sensitive HBV DNA testing is not feasible (Petersen, 2017; Urbani et al., 2010) 11

12 In Naomi-Khaing-Than-Hlaing (2007) study, 55 HBsAg negative and anti-hcv negative chronic liver disease patients with unknown aetiology were tested for occult B infection 52.7% (29/55) by nested PCR Among these, 89.7% (26/29) was found to be seropositive occult B infection (anti-hbc and/or anti-hbs) using ELISA 12

13 Prevalence of hepatitis B infection varies in different population groups in several studies Monks and novices are considered as high risk group as they have to reside in the same building, share the utensils and shave the head periodically with sharing of razors and blades 13

14 AIM AND OBJECTIVES AIM To study the serological status of hepatitis B virus infection among monks and novices at Buddhist monasteries in three Townships, Yangon 14

15 OBJECTIVES 1. To determine the seropositivity of HBsAg from serum samples of monks and novices by using ELISA 2. To determine the seropositivity of anti-hbc from serum samples by using ELISA 15

16 3. To determine the seropositivity of anti-hbs among HBsAg negative serum samples by using Immunochromatographic assay 4. To determine the occurrence of seropositive occult hepatitis B infection in the study population 16

17 MATERIALS AND METHODS 17

18 Study design Laboratory based cross sectional descriptive study Study period From January 2018 to October 2018 Study population Monks and novices residing at nine Buddhist monasteries in Thanlyin, Hmawbi and Shwepyitha Townships, Yangon 18

19 Sampling procedure A total of 255 blood samples were collected by random sampling - from monks and novices - residing at nine Buddhist monasteries - in three Townships, Yangon 19

20 Selection criteria Inclusion criteria Apparently healthy monks and novices residing at the study monasteries Exclusion criteria Monks or novices who had been immunized by hepatitis B vaccine previously 20

21 Detection of HBsAg HBsAg ELISA 3.0 from the Standard Diagnostics, Inc., Republic of Korea 21

22 Detection of anti-hbc anti-hbc ELISA from the Fortress Diagnostics, UK 22

23 Detection of anti-hbs SD BIOLINE anti-hbs ICT test device from the Standard Diagnostics, Inc., Republic of Korea 23

24 Flow chart Collection of 3 ml of blood Transported in ice box to Microbiology Research Laboratory, Department of Microbiology, University of Medicine 1, Yangon Serum separation by centrifugation Serum sample stored at -40 C until tested Each serum sample HBsAg by ELISA Anti-HBc by ELISA Positive Negative Positive Negative Anti-HBs by ICT 24

25 Working definition for variables Hepatitis B serological status Hepatitis B serological status means HBsAg, anti-hbc and anti-hbs serological markers in this study Operational definition Seropositive Occult Hepatitis B Infection Characterized by serum negative HBsAg and positive anti-hbc with or without detectable anti- HBs in serum (European Association for the study of the Liver, 2017) 25

26 Results 26

27 Figure 1. Age distribution of the study population 80% 70% 60% 50% 40% 30% 20% 10% 0% 67.8% 6.7% 4.3% 7.5% 3.1% 3.9% 6.7% < Age group (years) 27

28 Figure 2. History of risk factors for the study population 28

29 Figure 3. Frequency of HBsAg and anti-hbc in the study population 29

30 HBsAg ELISA Negative control Positive sample Positive control 30

31 Anti-HBc ELISA Blank well Negative control Positive sample Positive control

32 Figure 4. Frequency of anti-hbs in the study population Anti-HBs positivity rate was 23.1% (53/229) among HBsAg negative serum samples 32

33 Table1. Seropositive occult hepatitis B infection in the study population HBV marker status Seropositive occult B infection Number Percentage (%) HBsAg negative Anti-HBc positive Anti-HBs negative HBsAg negative Anti-HBc positive Anti-HBs positive Total

34 Table 3. Anti-HBc status based on the duration of stay at monasteries Anti-HBc status Duration Positive Negative Total of stay Number % Number % <1 year 1-5 years 6-10 years >10 years Total % % % % % % % % % %

35 DISCUSSION 35

36 In the present study, among 255 monks and novices, 26 (10.2%) were HBsAg positive and it was regarded as high prevalence rate according to WHO classification Moreover, 32.7% (75/229) were anti-hbc alone positive and 19.7% (45/229) were both anti-hbc and anti-hbs positive This finding indicated that 52.4% (120/229) had seropositive occult hepatitis B infection 36

37 Isolated anti-hbc positive (32.7%) monks and novices may have risk of disease progression and transmission to others Both anti-hbc and anti-hbs positive (19.7%) monks and novices may be resolved from HBV infection or may be seropositive occult B infection Therefore, these were needed to be confirmed by the nucleic acid testing due to the risk of transmission to others and disease progression 37

38 Seropositivity rate of anti-hbc was found to increase sharply with the duration of stay at the monastery highest in longer than 10 years duration of stay group, 84.2% (16/19) Under one year duration group had the lowest anti-hbc positivity rate, 36.8% (7/19) Persons of household contacts with HBV infection are reported to be at high risk of acquiring infection 38

39 Similarly, in the study of Myint-Myint-Sein (2017), 46.7% (7/15) of HBsAg seropositive contact family members were lived with HBV infected patients for more than 30 years 39

40 Generally, hepatitis B endemicity is classified by the HBsAg prevalence In the present study, anti-hbc (56.1%) was much higher than the HBsAg (10.2%) This indicated HBV infection was still high in Myanmar and needed to improve community awareness and preventive measures In screening of HBV infection, not only HBsAg but also anti-hbc should be considered to reduce the risk of transmission of HBV infection 40

41 CONCLUSION 41

42 Chronic HBV infection is one of the leading causes of preventable death in South East Asian countries Most of the infected individuals are unaware of their infection until they had serious complications 42

43 The rate of HBV infection among monks and novices was higher than general population (6.5%) This study showed higher prevalence of anti-hbc (56.1%) than HBsAg (10.2%) Moreover, 52.4% of monks and novices had seropositive occult hepatitis B infection 43

44 These anti-hbc positive persons should be confirmed by further nucleic acid testing and monitored because of the risk of progression and reactivation Among other HBV serological markers, anti-hbc should be integrated into routine screening test for HBV infection 44

45 THANK YOU 45