A Descriptive Study on Prevalence , Pattern and Coinfection of Hepatitis Viruses in Acute Infectious Hepatitis

Introduction: There is variability of data regarding seroprevalence and coinfection of hepatitis viruses. Our objective was to determine the magnitude, pattern and coinfection of hepatitis viruses in clinically suspected cases of acute infectious hepatitis. Methods: This descriptive study was conducted in the Department of Microbiology at Lady Hardinge Medical College, New Delhi, over a period of 1 year from January 2008 to December 2008. All the serum samples taken from subjects (n= 600 in study group and n=200 in control group) were tested for hepatitis B surface antigen (HBsAg), Immunoglobulin M (IgM) antibody against HAV, HCV & HEV using commercially available enzyme linked immunosorbent assay kit. Serum samples positive for HBs Ag were further tested for IgM capture anti hepatitis D virus (HDV) by ELISA methodology. We used SPSS Ver.10.0 (SPSS Inc. Chica go, Illinois) for the statistical analysis. The means of continuous variables among the groups were compared using the Student’s t-test while proportions were tested by Chi-square test. Results: Seroprevalence of acute viral hepatitis was 128/600 (21.3%) and 17/200 (8.5%) in study and control group respectively (p<0.05). HAV was the commonest cause 50/600 (8.3%) followed by HCV 33/600 (5.5%), HBV 24/600 (4%) and HEV 21/600 (3.5%). Coinfection rate among the study group was 11/128 (8.5%) and maximum coinfection rates were seen with HBV 8/11 (72%). 4/24 (16.6%) of the HBV infected cases were coinfected with HDV. Male predominance was seen for all the markers. Overall sex wise seropositivity in males was 81/362 (22.3%) and 47/238 (19%) in females in study group while it was 14/121 (11.5%) and 3/79 (3.7%) respectively in controls. Conclusions: Acute infectious hepatitis is a significant burden on the society. HAV is the predominant form of acute viral hepatitis. HBV, HCV and HEV were other leading causes of acute viral hepatitis. Coinfection of HBV with HDV is the commonest pattern.


INTRODUCTION
Acute viral hepatitis is predominantly caused by hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), HBV associated delta agent or hepatitis D virus (HDV) and hepatitis E virus (HEV).Illness ranges from asymptomatic or in apparent infections to acute fulminant infections. 1 Sub clinical persistent infections and rapidly progressive chronic liver disease with cirrhosis and hepatocellular carcinoma is the other spectrum of infection. 1The differentiation of these viruses is based on serological and molecular markers.Acute viral hepatitis is defined by an acute self limiting disease with serum aspartate amino transferase elevation of at least five fold and/or clinical jaundice. 2AV is a single stranded ribonucleic acid (RNA) virus transmitted by feco-oral route. 3Hepatitis A virus infections occur sporadically or as outbreaks. 4Overt illness is seen only in about 5% of infected individuals. 5hronic carrier state is not seen with HAV infections.
Clinical manifestations consist of fever, malaise, anorexia, nausea, vomiting, which usually subside with the onset of jaundice. 6HAV illness is a self limiting disease characterized by complete recovery. 7Rarely, a rapidly fatal fulminant hepatitis may follow.Hepatitis B virus is a deoxyribonucleic acid (DNA) virus and belongs to Hepadnaviridae family.It is transmitted by parenteral, sexual or perinatal mode.Worldwide over 300 million persons are chronically infected with HBV and 75% among these are in Asia alone. 8The average estimated carrier rate of hepatitis B (HBV) in India is 4.7%. 9Hepatitis B virus infections draw a global concern because of its potential to cause acute and chronic hepatitis (70%), liver cirrhosis (80%) and primary hepatocellular carcinoma. 10epatitis C virus (HCV) is a single stranded ribonucleic acid virus and is the commonest cause of post transfusion hepatitis.infected with HCV. 12 About 75% of infections are sub clinical and revealed only accidentally by abnormal liver function tests and/or anti HCV positivity. 13Complications include chronic hepatitis (70%), cirrhosis (20-30%), hepatocellular carcinoma and liver failure. 14Approximately 7-8% of HCV positive women transmit the virus to their offspring.The rate of transmission is even higher amongst women co infected with HIV. 15 Hepatitis D virus is a defective satellite virus, requiring HBV as helper virus. 16HDV is transmitted by parenteral, sexual and perinatal routes.Infections can occur as simultaneous infection with HBV or as super infection of an HBsAg carrier by HDV. 17 HDV infection can be prevented by prevention of coinfection with HBV or of super infection with HBV carrier and requires all the measures that apply to the prevention of HBV infection. 18epatitis E virus belongs to the family calciviridae, with single stranded RNA genome, responsible for a substantial proportion of cases of enterically transmitted non A non B hepatitis in young and middle aged adults. 191] Mortality from HEV related illness in pregnancy ranges between 35-40% and could be as high as 70%. 224][25] There is variability of data regarding prevalence of different markers of hepatitis.There are very few Indian studies precisely depicting the coinfection rates with various hepatitis viruses.Precise data on seroprevalence of different hepatitis viruses will help quantify the burden correctly and authorities can accordingly strategize the preventive measures.

MATERIALS AND METHODS
This descriptive study was conducted in the De partment of Microbiology at Lady Hardinge Medical College, New Delhi, which is a tertiary care hospital in urban Northern India, over a period of one year from January 2008 to December 2008.Subjects were divided into 2 groups.Group 1 was the study group of 600 patients with clinically suspected infec tious hepatitis attending the outpatient department of various specialties in Kalawati Saran and Smt.Sucheta Kriplani Hospital, New Delhi both attached to Lady Hardinge Medical College.Group 2 was the control group of 200 age and sex matched patients showing no clinical evidence of acute infectious hepatitis.200 patients attending various outpatient departments at our hospital were enrolled as controls as only these many were comparable according to clinical and laboratory criteria.We could enroll 600 cases and 200 controls in the study duration.

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Recent onset of jaundice (<6 months) defined by serum bilirubin level >2.5 mg/dl and/or increase in serum transaminase >5 times the upper limit of normal.• Fever in absence of chronic liver disease or past history of jaundice.

Exclusion criteria for cases
• History of chronic liver disease or past history of jaundice with duration of illness more than 6 months.

•
Acute fatty liver of hepatitis or alcoholic hepatitis or intrahepatic cholestasis.Routine blood samples received in the serology section of Department of Microbiology from patients suspected of acute infectious hepatitis were analyzed.The sera were separated and stored frozen (−70°C) until tested for the viral markers.All the serum samples taken from subjects (study and control group) were tested for HBsAg using commercially available enzyme linked immunosorbent assay kits. 1. Antibody to hepatitis A virus (IgM anti HAV) (ELISA; Biokit®, Barcelona, Spain).2. Hepatitis B virus surface antigen (HBsAg) (ELISA; Biokit®, Barcelona, Spain).3. Antibody to hepatitis C virus (IgM Anti HCV) (ELISA; Express Bio Life Science Products, USA). 4. Antibody to hepatitis E virus (IgM anti HEV) (ELISA; ORGENICS Ltd) Informed con sent and institutional review board approval was taken from ethics committee for the study bearing protocol number MIC 07/312.We used SPSS Ver.10.0 (SPSS Inc.Chica go, Illinois) for the statistical analysis.The means of continuous variables were compared using the Student's t-test and categorical variables were com pared using the Chi square test and the Fisher's ex act test, as appropriate.A p value of less than 0.05 was considered to be significant.

RESULTS
The study group comprised of 362 male and 238 female patients.The overall male to female ratio was 1.5:1 and thus a male preponderance was seen in study group.The control group (n = 200) comprised of 121 males and 79 females with overall male to female ratio of 1.5:1.The study and control group were divided age wise, i.e., 0-10 years,11-20 years, 21-30 years, 31-40 years and >40 years.The percentage of males was not different between cases and controls (P = 0.125).The mean age in the study group was 20.2 ± 15.2 years while in the control group it was 19.65 ± 14.8 years.The mean age of study and control group was not different (P= 0.46).Table 1 shows Age and Sex Distribution in Study and Control Groups In the study group, a total of 600 samples were tested for various viral markers.Out of 600, 472 (78.7%) were negative, whereas 128 (21.3%) were positive for viral markers while in the control group a total of 200 samples tested for various viral markers.Out of 200, 183 (91.5%) were negative whereas 17 (8.5%)were positive for viral markers.The difference between the overall seroprevalence in the study group (21.3%) and the control group (8.5%) was statistically significant (p<0.05)In the study group, the overall seroprevalence for IgM anti HAV was 50/600 (8.3%) as compared to 4/200 (2%) in the control group.The difference was statistically significant (p<0.05).The overall seroprevalence of HBsAg in the study group was 24/600 (4%) as compared to 5/200 (2.5%) in the control group, the difference was statistically not significant.The overall seroprevalence of IgM anti HCV in the study group was 33/600 (5.5%) while that in the control group was 3/200(1.5%), the difference was statistically significant (p<0.05).The overall seroprevalence of IgM anti HEV in the study group was 21/600 (3.5%) as compared to 5/200 (2.5%) in the control group.The difference was statistically not significant (p>0.05).

DISCUSSION
India has a widespread clinical problem of acute viral hepatitis.Acute viral hepatitis in India is largely attributed to hepatotropic viruses. [26]29][30][31] The total infective pathology was serologically detected in 128 (21.3%) out of 600 samples suspected of acute infectious hepatitis in the study group while 17 (8.5%) of the 200 samples in control group.Different authors have reported different prevalence rates of acute viral hepatitis in and around Delhi. [27][28][29] Zahid et al (2006, New Delhi) studied 3495 patients with acute suspected hepatitis and found the total infective pathology as 35.1%.The seroprevalence for IgM anti HAV, HBsAg, IgM anti HCV and IgM HEV was 11.4%, 9.1%, 1.1% and 14.5% respectively. [28]he serology trends for acute viral hepatitis in North India showed a gradually decreasing trend in the recent years.The seroprevalence  The maximum cases of co infection were associated with hepatitis B because it is known to be a highly infectious virus with infectivity rate 100 times as that of HIV.Secondly, HBV is highly prevalent in India and the total HBV carrier pool in India is around 43 million. 43Nearly 1 million cases are added to the existent HBV pool in India yearly. 43Co infection between HBV and HDV is attributed to the fact that HDV being a defective satellite virus, is usually transmitted along with HBV as co infection or as super infection.Some studies have shown high frequency of dual HBV/ HDV infection prevailed in patients with hepatocellular carcinoma and was suggested that florid replication of both HBV and HDV and the resulting severe necro inflammation may be an additional factor for promotion of hepatocellular carcinoma. 44It has been suggested that HBV-HDV coinfections are significantly higher in acute hepatitis while super infection predominate in chronic liver disease. 17BV and HCV have common modes of transmission and rarely these viruses can exist together.Beniwal et al (New Delhi, 2003) who recorded a dual infection with HBV and HEV in 4.1% of HBV infected cases. 45The coinfection between HEV and HBV could be explained by the population residing in mesoendemic zone for HBV and the possibility of reactivation of latent HBV due to clinical HEV.We also noted the co-occurrence of HAV and HEV in one case (9%).This feature probably suggests either food or water as common vehicle for disease transmission.

CONCLUSIONS
Hepatitis viruses remain a major etiology for acute viral hepatitis.Both enterically transmitted and parenterally transmitted hepatitis viruses are a problem in India contributing significantly to disease burden.HAV and HEV are common causes of enterically transmitted acute viral hepatitis.All four hepatitis viruses are predominantly infecting male patients.HBV and HCV are common causes of parenterally transmitted acute viral hepatitis.In majority of cases coinfection between HBV and HDV occur together.As most of the cases of acute viral hepatitis are preventable, appropriate measures should be undertaken to limit their spread.
In the control group, the overall seropositivity for different viral markers in the control group was 2% for IgM anti HAV, 2.5% for HBsAg, 2.5% for IgM anti HEV and 1.5% for IgM anti HCV.During the study period, there was no acute viral hepatitis outbreak reported in the region.Seroprevalence of anti-HAV IgM recorded by diff erent authors in and around Delhi in recent years is between 2.3% to 11.4%. 25,27,30,31Our findings were comparable with the recent stud ies and we found that the seroprevalence of acute HAV infection as 8.3%. Population surveys show that one third of the people reside below the poverty line with poor sanitation and low socio-economic status which contributes to increased susceptibility to infections.
Our study demonstrated an overall seroprevalence rate for HBV as 4% in the study group while 2.5% in the control group.The HBsAg seroprevalence recorded by different authors in and around Delhi varied from 8 to 42.5% respectively. 25,27,34 D29]34 The reduced prevalence rates in our study could be attributed to integration of HBV vaccination into Universal immunization program and free availability of vaccine.Quality checks in blood bank by stringent screening practices and community awareness campaigns proved pivotal in disease control.The Seroprevalence rate of HBsAg in general population in our study was 2.5%.Various studies have recorded the seroprevalence rate of HBsAg in general population between 0.97 and 9.5%. 35,36Overall HBV carrier rate in India has not changed during the last decade, although the carrier part has increased by nearly 5 million, due to an increase in the total population of the country. 37he study recorded an overall seroprevalence rate of HCV as 5.5% in the study group and 1.5% in the control group.Seroprevalence of IgM anti HCV recorded by different authors in and around Delhi ranged from 3% to 12%. 25,27,29,30HCV seropositivity trends from 1997 to 2002 showed a gradual decline from 12% to 3.3% with an increasing trend in last few years. 25,27,29,30 Te decline was attributed to ban by Supreme Court of India on professional blood donations. 38Professional blood donations were an accepted practice until 1997. 38This ban curtailed the transmission of HCV through unscreened blood donations.] Unsafe injecting practices, intravenous drug abuse and unsafe sex practices, all have a contributory effect on the overall seroprevalence of HCV. 40The seropositivity rate of IgM anti HCV among the general population in our study (1.5%) was comparable with other studies (1.03-1.7%). 35,41Pahuja et al. found HCV seroprevalence of 0.66% in hospital based study with 4014 subjects. 41he seroprevalence rate of anti-HEV IgM in our study was 3.5% while in the control group it was 2.5%.No outbreak of acute hepatitis E was reported during the study period in Delhi.Few authors have reported high prevalence rates for anti-HEV IgM in and around Delhi during recent years. 27,30However, our study showed comparatively low prevalence rates.This could be explained by no reported outbreak of hepatitis during the study period.Secondly, our hospital caters to pedi atric patients and more than 50% of the patients were in the pediatric age group.HEV infection is commoner in young adults and less number of adults was included in our study.Delhi is an endemic zone for HEV and several outbreaks have occurred. 42 11 HCV transmission occurs by needle stick injuries, transfusion of unscreened blood and through unsafe sexual practices.It is estimated that 200 million people worldwide are International Journal of Medicine and Public Health, Vol 6, Issue 4, Oct-Dec, 2016

Table 2 : Overall Seroprevalence of acute viral hepatitis in Study and Control Groups
* p value < 0.05 = significant International Journal of Medicine and Public Health, Vol 6, Issue 4, Oct-Dec, 2016