Desi Rotaviral Vaccine
Can Save A Lakh Children Annually
Rotavirus is the most common cause of
severe diarrheal (gastro enteritis) disease in infants
and young children globally. Children under five years of age, especially those
between 6 months and two years are most vulnerable to this disease. Rotaviruses
are estimated to be responsible for approximately 5, 27,000 deaths each year,
with more than 85% of these deaths occurring in low-income countries in Africa
and Asia, and over two million are hospitalized each year with pronounced
dehydration.
Among 43 countries participating in the
Global Surveillance Network for rotavirus in 2009, 36% of hospitalizations for
diarrhea among children aged below 5 years were caused by rotavirus infection.
Rotavirus affects populations in all socio-economic groups and is equally
prevalent in industrialized and developing countries. So differences in
sanitation practices or water supply are not likely to affect the incidence of
the infection.
The name Rotavirus comes from the
characteristic wheel-like appearance of the virus when viewed by electron
microscope (the name rotavirus is derived from the Latin word Rota ,
meaning "wheel”). Rota viral
diarrhea is an infection of the stomach and bowel. It spreads when infected
children do not maintain proper personal hygiene. Virus spreads by contact or
airborne route. Most cases of gastroenteritis in children are mild and usually
pass within 3-5 days without the need for treatment. However, young children,
particularly those under two years of age, are at risk of dehydration. So it is
very important that they drink plenty of fluids. In severe cases of
gastroenteritis, where there has been significant fluid loss, hospital
treatment may be required so that fluid can be replaced through drips.
The first rotavirus infection tends to
be the most severe because the body builds up immunity (resistance) to the
virus afterwards. This is why these types of infections are extremely rare in
adults. It is estimated that every child will have at least one rotavirus
infection before the age of five. Most infections occur among children aged
between three months and three years old.
In India , nationally representative
data on the incidence of severe rota virus
disease is lacking. However, studies have revealed that on an average 34% of
all diarrheal hospitalizations are due to rota virus
infection and the proportion of severerota viral infection has not decreased in
the last few years, similar to the global trend indicating that improved
sanitation and use of anti-biotics have not been effective onrota virus.
The prevalence of Rota virus in new born is high in India to the extent of 73%, but
these infections are normally a- symptomatic and the likelihood of acquiring
infection increases with the length of stay in the hospital.
While some studies in India have
found no association between rotavirus infection and time of year, most have
observed an increase in rotavirus-associated diarrhea during the winter months,
October to February, throughout the country. The observed proportion of
rotavirus cases occurring in the cooler season has ranged from 59% to 72%.
Treatment & Prevention
No specific treatment exists for
rotavirus gastroenteritis, and repeat infections are common in children. Since
2006, vaccines are available for rotavirus infection. Prior to the availability
of a vaccine, almost all children became infected with rotavirus by their third
birthday. Repeat infections with different viral strains were possible. After
several infections with different strains of the virus, children acquire
immunity to rotavirus. Adults sometimes get infected, but the resulting illness
is usually mild.
Use of vaccine should be part of a
comprehensive diarrhoeal disease control strategy including,
among other interventions, improvements of hygiene and sanitation,
administration of oral rehydration solution and overall improved case
management.
A new vaccine called ROTAVAC has been
developed by a joint vaccine development initiative supported by Department of
Biotechnology, Government of India, the Bill & Melinda Gates Foundation,
the Research Council of Norway, and the UK Department for International
Development with Bharat Biotech investing on important activities towards
vaccine development. ROTAVAC is an oral vaccine and is administered to infants
in a three-dose course at the ages of 6, 10, and 14 weeks. It is given
alongside routine immunizations in the UIP vaccines recommended at these ages.
Currently two-rotavirus vaccines are
available in the international market, namelyRotarix and Rotateq. These vaccines are less effective against
medically attended rotavirus diarrhea in lower income settings. Reasons for
this could be high prevalence of other intestinal infections, malnutrition,
tuberculosis etc. Further, the efficacy of rotavirus vaccine decreases with lower
percentage of coverage under routine immunization. Improving the overall performance of
the immunization system is critical to the success of any vaccine introduction.
Several rotavirus vaccines research
projects are under way in India .
Cost effectiveness of rotavirus vaccine has been evaluated in two separate
studies. In one of the studies third stage clinical trial of ROTAVAC is over.
At a price of US $ 1 (Rs. 50/- approx), the price set by Bharat Bio-Tech, cost
effectiveness in terms of disability adjusted life year, satisfy the WHO/
UNICEF criteria for a cost- effective intervention.
ROTAVAC represents the successful
research and development of a novel vaccine from the developing world with
global standards. The clinical trial results indicate that the vaccine, if
licensed, could save the lives of thousands of children each year in India .
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