The Vaccine tried in Indian Slums may finally eradicate typhoid

[Pintu]

http://ptinews.com/news/190645_Vaccine-tried-in-Indian-slums-may-eradicate-typhoid

Vaccine tried in Indian slums may eradicate typhoid

STAFF WRITER 19:18 HRS IST

Washington, July 23 (PTI) Typhoid, a long-time scourge, may finally be eradicated in India with a vaccine, which has been tried on slum-dwellers in Kolkata, proving highly effective.

The vaccine, tested on children, not only prevented infection in those who received it, but also those who came in close contact with the affected, a new study said.

The experiments may support World Health Organisation's efforts to eradicate typhoid, a deadly disease in tropical countries.

Conducted by Seoul based International Vaccine Institute (IVI) in collaboration with the National Institute of Cholera and Enteric Diseases (NICED)of Kolkata, the study was published in today's issue of New England Journal of Medicine (NEJM).

It says that typhoid fever is a major cause of illness and death in the developing world, killing an estimated 216,000 to 600,000 people annually.

 

[Pintu]

Typhoid Vaccine Effectively Prevents Disease In Children, Study Finds - Kaiser Global Health

Typhoid Vaccine Effectively Prevents Disease In Children, Study Finds

Thursday, July 23, 2009

"A typhoid vaccine proved effective in the slums of India, where it not only helped prevent infection in children who received it, but also those in close contact who were unvaccinated," according to a New England Journal of Medicine study published on Thursday, the AP/Washington Post reports (Chang, 7/22).

The study, "conducted in two wards of an Indian slum where about 60,000 people live," sought to investigate the Vi typhoid vaccine's efficacy in children between the ages of 2 and 5, Reuters writes. "Doubt about its effectiveness in this younger age group is one reason the shots, which cost as little as 50 cents, are not widely given to prevent typhoid. The potentially deadly disease comes from contaminated food and water, and kills 216,000 to 600,000 people worldwide each year," according to the news service (Emery, 7/22).

Researchers found that the vaccine was 80 percent effective in preventing typhoid fever among the children in the study. The vaccine also offered 44 percent protection among "unvaccinated neighbors who were in contact with the immunized children," according to the AP/Washington Post. "Overall, the vaccine was 61 percent effective," the newspaper reports.

Though typhoid fever is treatable with antibiotics, new drug-resistant strains have arisen (7/22). In addition, "Safe and effective vaccines exist but are used mainly by wealthy travellers to developing countries rather than by poor residents," AFP/Google.com writes (7/23).

According to the AP/Washington Post, the study was funded by the Bill and Melinda Gates Foundation and coordinated by the International Vaccine Institute (IVI). GlaxoSmithKline donated the vaccine used in the research (7/22).

In an IVI statement, IVI Director-General John Clemens said, "The protection for children under the age of five years is important because this age group has been shown to be at high risk for typhoid fever in many areas where the disease is endemic" (7/22). In a related NEJM commentary, Myron Levine of the University of Maryland School of Medicine wrote, "The time has come to implement use of these vaccines vigorously and monitor the effect of such intervention," according to Reuters (7/22).

 

[Pintu]

Typhoid vaccine protects younger children -study | Reuters

Typhoid vaccine protects younger children -study
Wed Jul 22, 2009 5:23pm EDT

* Vaccine worked best in youngest children

* Cheap vaccine provides herd immunity

By Gene Emery

BOSTON, July 22 (Reuters) - GlaxoSmithKline's (GSK.N) (GSK.L) Typherix vaccine shields children as young as 2 from typhoid fever, and widespread vaccination can even protect people who have not been given the shot, according to a study published on Wednesday.

The test, conducted in two wards of an Indian slum where about 60,000 people live, was designed to see how well the Vi-type vaccine works in youngsters age 2 to 5.

Doubt about its effectiveness in this younger age group is one reason the shots, which cost as little as 50 cents, are not widely given to prevent typhoid. The potentially deadly disease comes from contaminated food and water, and kills 216,000 to 600,000 people worldwide each year.

At the end of 2004, 37,673 children and adults were inoculated with Typherix or, for comparison purposes, GlaxoSmithKline's Havrix vaccine for hepatitis A. Several companies make the typhoid vaccine.

It worked in 61 percent of the people exposed to the disease, said the team led by Dr. Dipika Sur of the National Institute of Cholera and Enteric Diseases in Kolkata, India.

It was most effective in children under 5, where the protection rate was 80 percent.

"This protection for children under the age of 5 years is important because this age group has been shown to be at high risk for typhoid fever in many areas where the disease is endemic," the researchers wrote in the New England Journal of Medicine.

The protection level dropped to 56 percent for 5- to 14-year-olds, and was 46 percent for those 15 and over.

When enough people were vaccinated, spread of the disease slowed through the community, protecting even people who did not receive the shots, a phenomenon known as herd immunity.

In the community as a whole, immunization blocked 57 percent of typhoid cases among both vaccinated and unvaccinated people, the Sur team concluded.

"This is important new information," Dr. Myron Levine of the University of Maryland School of Medicine wrote in a commentary.

"The indirect protection of nonvaccinated persons by the Vi vaccine further bolsters the case for school-based immunization to control endemic typhoid, since one might expect some indirect protection of preschool children as well," he wrote.

In addition to the Vi vaccine, which sensitizes people to a part of the typhoid bug, there is an oral Ty21a vaccine that uses a chemically weakened strain of the bacteria.

However the Ty21a capsule or liquid must be given in at least three doses, which poses logistical difficulties except in organized settings such as schools.

"The time has come to implement use of these vaccines vigorously and monitor the effect of such intervention," wrote Levine.

Typhoid fever can last for weeks or months without antibiotic treatment and up to 20 percent of cases can die from the disease.

(Editing by Maggie Fox)