Be on guard against liver diseaseTimes of India
28 July 2012
Population Remains At High Risk Of Hepatitis E Due To River Contamination
By:Umesh Isalkar TNN
Last month an outbreak of hepatitis E struck Ichalkaranji, killing at least 15 people and leaving over 6,700 sick. The epidemic brought to the fore the fact that hepatitis E continues to be a widespread problem in areas with an inadequate sewage disposal system and water treatment measures.
A study conducted by the National Institute of Virology (NIV) in 2010 has also found an alarming rise in the prevalence of the hepatitis A and E viruses in the Mutha river over the last eight years.
The hepatitis E virus is transmitted via the faecaloral route, principally via contaminated water. Risk factors for hepatitis E are related to poor sanitation in large areas of the world and shedding of the hepatitis E virus in faeces.
"The water flowing through the Mutha river has a high prevalence of jaundice–causing viruses and is a potential health hazard to the city’s population," says scientist Vidya Arankalle, senior deputy director of NIV. "This could pose a threat to the drinking water supply system and to public health."
The study documents that although Pune’s drinking water supply system is safe with respect to enteric viruses, the viruses are present in the Mutha river. However, in case of accidental contamination, which could happen during a breakage in the pipelines which carry the drinking water, or when the river overflows during the monsoon, this could prove dangerous, Arankalle said.
"Besides the hepatitis A and E viruses, our study documented high prevalence of enteric viruses, human enteroviruses (coxsackievirus, echo virus and others) which cause a range of infections, as well as rota viruses which cause dysentery."
"This is the first study to systematically document the presence of viruses in the river and it also provides an insight into the extent to which the river has been contaminated with human enteric viruses," Arankalle said.
Compared to an earlier study conducted in 1999, it shows a significant increase in the prevalence of hepatitis A from 24.4 per cent to 76.5 per cent and hepatitis E, from 11 per cent to 25 per cent, she said.
Outlets from two sewage treatment plants and untreated sewage from several open drainage lines are discharged into the river as it passes through the city. A few industries and the huge slum areas directly release sewage into the river. As per estimates, about 350 million litres of sewage is directly released into the river without treatment.
"During the hepatitis E outbreak, we tested water samples of the river in Ichalkaranji and found the presence of the hepatitis E virus. After the administration undertook super chlorination methods, we once again took the river water samples and tested them but didn’t find any virus then," Arankalle said.
t The incubation period following exposure to the hepatitis E virus ranges from three to eight weeks, with a mean of 40 days. The period of communicability is unknown
The hepatitis E virus causes acute sporadic and epidemic viral hepatitis. Symptomatic infection is most common in young adults aged 15 to 40 years. Although infection is frequent in children, the disease is mostly asymptomatic or causes a very mild illness without jaundice (anicteric) that goes undiagnosed
Jaundice (yellow discoloration of the skin and sclera of the eyes, dark urine and pale stools) t Anorexia (loss of appetite) t An enlarged, tender liver (hepatomegaly) t Abdominal pain and tenderness t Nausea and vomiting t FeverPrevention The risk of infection and transmission can be reduced by:
Maintaining quality standards for public water supplies
Establishing proper disposal systems to eliminate sanitary wasteOn an individual level, infection risk can be reduced by:
Maintaining hygienic practices such as hand-washing with safe water, particularly before handling food
Avoiding drinking water and/or ice of unknown purity
Avoiding eating uncooked shellfish, and uncooked fruits or vegetables that are not peeled or that are prepared by people living in or travelling in highly endemic countries