The news of success of the first field trial of a new typhoid vaccine in young children was covered with much fanfare in the global media quoting scientists who called it a game-changer in the fight against the disease.
But it was received with skepticism in the social media here with most complaining that Nepalis have been used as guinea pigs for risky medical research by the affluent countries.
Setopati talked with the relevant authorities in Nepal that claimed the vaccine trial conducted by the Baltimore-based Typhoid Vaccine Acceleration Consortium--a partnership between Oxford University, the University of Maryland School of Medicine and the international nonprofit organization PATH, was done following due procedures in Nepal.
National Health Research Council (NHRC) official Nirbhaya Sharma told Setopati that the trial, that started in November 2017, was done taking ethical permission from the NHRC, the Department of Drug Administration and the Child Health Division.
The typhoid conjugate vaccine (TCV) was first tried on 112 healthy volunteers in the United Kingdom by Oxford which showed that it protected against the disease.
But trials of TCVs had not been conducted on endemic populations. So trials, funded by the Bill and Melinda Gates Foundation, were started in many countries where typhoid is endemic with Professor of Paediatric Infection and Immunity at Oxford University's Department of Paediatrics Andrew Pollard the chief investigator.
"The trial has been conducted here in Nepal due to high prevalence of typhoid," Dr Buddha Basnet of Patan Hospital, the principal investigator for the trial in Nepal, answered when asked why Nepal was chosen for the trial.
He revealed that the trials have also been conducted in India, Bangladesh, and Malawi and Burkina Faso of Africa. "Prevalence of typhoid is 500 per 100,000 in South Asia," he pointed.
The World Health Organization’s Global Advisory Committee on Vaccine Safety had already endorsed the vaccine following the trial in UK before the start of trial in Nepal.
Dr Basnet says he agreed for taking part in the trial because it was already tried in the UK which was reported by The Lancet, was endorsed by the WHO and was being carried out by Oxford University.
He refutes guinea pig allegations pointing that the vaccine, produced by Bharat Biotech International of Hyderabad, India, is already being used in Pakistan that has been suffering from an antibiotic-resistant typhoid outbreak. "Vaccines produced in India would not be used in Pakistan if it were not good," he argues.
Pakistan's current typhoid outbreak is the first-ever reported outbreak of ceftriaxone-resistant typhoid, the researchers point, and represents an alarming trend in the spread of drug-resistant typhoid. The strain is resistant not only to ceftriaxone, the standard treatment in many parts of the world, but also to the majority of antibiotics commonly used for typhoid, making it increasingly challenging and costly to treat.
"If the vaccines are administered in the kids they will not get typhoid which makes tackling the antibiotic-resistant typhoid that much easier," Dr Basnet adds.
One dose of the vaccine was given to 10,005 children in Lalitpur. Another 10,014 were immunized against meningococcal disease (MenA) to serve as a control group.
The New England Journal of Medicine, that published the preliminary analysis of the trial in Nepal, states that children between nine months and 16 years who were in good health at the time of enrollment, and whose parents or legal guardians were willing and competent to provide written informed consent were eligible to participate. "All the parents and guardians of the participants provided informed consent," Dr Basnet claims.
But the trial was a randomized control trial (RCT) and a blinded one at that meaning that the children and their parents did not know whether they were administered TCV or MenA.
The preliminary analysis says the TCV provided protection for 81.6% of recipients. "It led to immune response in the participants resulting in formation of antibodies in significant quantity after 28 days," Dr Basnet reveals.
"This is the first study to show that a single dose of TCV is safe, immunogenic, and effective, which provides clear evidence that vaccination will help efforts to control this serious disease and is a strong endorsement of the WHO policy for vaccine implementation," the New England Journal of Medicine quoted chief investigator Dr Pollard as saying.
Five percent of the children who were administered TCV had fever within seven days while 1.4 percent had vomiting and diarrhea. One death occurred due to staphylococcal sepsis seven months after vaccination but that was not related to TCV, according to the journal.
Dr Basnet points that children are more prone to typhoid as their immune system is not well developed and adults may already have developed antibodies against the disease but claims that the vaccine will be effective even in the adults. "The vaccine is primarily for children but it can provide protection for even adults like us," he assures.
Caused by the bacterium Salmonella Typhi, typhoid is a major cause of fever in children in low- and middle-income countries and spreads through contaminated food and water.
There are nearly 11 million cases and more than 116,000 deaths a year worldwide, according to the WHO.
There are two existing typhoid vaccines. One comes in a capsule that is too large for younger children to swallow, so it is for youngsters over six years. The other, delivered as an injection, doesn’t work in children under age two, Reuters has reported.
The TCV has been administered on children as young as nine months and can be universally used on all children and is expected to provide protection over longer term.
Dr Basnet says the participants will still be under observation to collect data for medium and long-term analysis.
