‘Why vaccination against typhoid fever must be ensured’

Typhoid fever  is a common worldwide illness, transmitted by the ingestion of contaminated food or water. However, Mr Tonye Briggs, Managing Director, Creative Ideas Pharmaceutical Limited in this interview by SADE OGUNTOLA, said it is possible to be free of this infection through vaccination.

 
ADVERTISEMENT
The rainy season is here, and with water logging a common sight around every corner, cases of people suffering from fever, including typhoid are rising.

Typhoid fever is a life threatening disease that is caused due to an infection by the bacterium, Salmonella typhi. The World Health Organisation (WHO) has deemed typhoid fever a serious problem in endemic areas (India, Southeast Asia, Africa, Central and South America) where there are between 16 and 33 million cases each year that result in over half a million deaths.

The bacterium, Salmonella typhi, is present only in human beings and is transmitted through contaminated food or water. People with this infection carry the bacterium in their intestines and bloodstream, and those who have recovered from the disease could still have the bacterium in their system; they are known as 'carriers' of the disease.

Both ill people and carriers shed Salmonella typhi in their stool. Infection is usually spread when food or water is handled by a person who is shedding the bacterium or if sewage water leaks into drinking water or food that is then consumed. That is why this disease is common in areas where proper hand washing techniques are not followed.

Typhoid symptoms include high fever, weakness, stomach pains, headache, loss of appetite, and sometimes a rash. Infection can spread to many other places in the body (such as bones) and can cause rupture of the intestine. It kills up to 30 per cent of people who get it, if they are not treated.

Antibiotic therapy reduces deaths and complications caused by typhoid fever. However, in recent years S. Typhi has acquired resistance to many of the antibiotics most widely available for its treatment, thus the need for vaccination to prevent this infection and its complications, said Mr Tonye Briggs, Managing Director, Creative Ideas Pharmaceutical limited.

Mr Briggs said “typhoid fever is prevalent in Nigeria; the down side to it is that most times it is usually mistaken for malaria and it is after the symptom persists that they would now tell the person to go for test. From our research, we have lost many people. However, this vaccine when taken once can protect against the infection for three years.

“Personally, I haven't had typhoid fever, but some of my friends have. They all said it was not a funny experience. In fact, one kept having a recurring incidence of the infection. He was one of those people that pushed me into venturing into ensuring a typhoid vaccine is available in Nigeria,” he said.

The high risk of Nigerians coming down with typhoid fever coupled with their low purchasing power when they develop the infection, Mr Briggs said, has made vaccination key to reducing deaths and ill health from the infection.

Vaccination had supported Vietnam to record zero cases of typhoid fever, a condition that Nigeria is still battling with in. However, he said not many people are aware of Tyvivac vaccine that protects against thyroid fever, thus explaining why even NADFAC officials were at Vietnam to verify the efficacy of the typhoid fever manufactured in the country.

“As a company, we realised thyroid fever has great financial burden. For us as a company, we believe that prevention is better than cure, so if we can prevent and reduce the rate of typhoid fever in Nigeria, it would really go a long way in the attainment of the millennium development goals,” he declared.

“Over the last four years, we have made several trips to Vietnam to meet with our partners and the manufacturer, Dalat vaccine Company, DAVAC. The process of ensuring the safety and efficacy of this vaccine include factory visits to Vietnam with NAFDAC inspectors who were convinced that the production processes met global best practices and standards. Clinical trials and other tests were administered and the verdict, eventually, was that the vaccine is safe and effective in the management of typhoid,” he added.

The Trade Attache from the Embassy of the Socialist Republic of Vietnam recalled that Vietnam was in the situation of Nigeria before it discovered the vaccine and that with its introduction the burden of typhoid has been drastically reduced.

However, he explained that Tyvivac vaccine is safe for individuals above the age of two years and the individual only need to take a single dose.

While nursing mothers and pregnant women are not legible for the vaccine, he said its use in individuals with chronic conditions such as hypertension and diabetes is safe. Also, its administration alongside other vaccines such as hepatitis and influenza vaccines, he assured to be safe too.

In the quest to bring succour to many who have been affected by this scourge, he said governments at all levels need to buy into the idea of ensuring Nigerians are protected from typhoid fever through vaccination.

He declared: “if government buys into this, the rate of typhoid fever in Nigeria will reduce. It is also for this reason we are reaching out to wholesalers of pharmaceutical drugs and different partners in the pharmaceutical chain to help ensure the availability of this vaccine in the nook and crannies of the country.”

Moreover, Mr Briggs added that in checking faking, the vaccine carries security proof, adding that training is also on to ensure that organisations involved in its distribution maintains a cold chain to ensure its potency is maintained.

For this vaccine, whose cold chain must be maintained, and which takes about four months to be manufactured before it is thyen freight to Nigeria, he said many individuals had applauded as a welcome development to prevent this infection whose complications could sometimes be deadly.

There are two vaccines that are recommended by the World Health Organisation. The vaccine works by stimulating the immune system to recognise a particular bacterium or virus and initiate the fight back in the event of future infection.

For instance the oral vaccine based on the live, attenuated mutant strain of S. typhi Ty21a (Ty21a vaccine), is supplied in enteric coated capsules. In Australia and Europe, three tablets are given on days 1, 3, and 5; this series is repeated every year for individuals travelling from nonendemic to endemic countries, and every three years for individuals living in countries or areas at risk.

The duration of protection following Ty21a immunisation is not well defined and may vary with vaccine dose and possibly with subsequent exposures to S. typhi (natural booster).

In addition, the injectable Vi capsular polysaccharide vaccine (ViCPS vaccine) is given intramuscularly in a single dose. Protection is induced about seven days after the injection. In countries or areas at risk, the protective efficacy 1.5 years after vaccination is about 72 per cent; after three years it is about 50 per cent. The vaccine is licensed for individuals aged above two years. To maintain protection, revaccination is recommended every three years.

Basically, the live Salmonella vaccines enhance the ability of the immune system to prevent the bacteria from replicating and spreading to other organs. They can also prevent the spread of the bacteria   into the bloodstream, which causes a condition known as bacteraemia, a major killer of children in Africa.

The live vaccine appears superior to the live attenuated vaccine because it induces a response that both kills the bacteria and restrains their growth, leading to elimination of the infection. However, as with every other vaccine, there can be minor reactions including pain and redness at the injection site, headache, fatigue or a vague feeling of discomfort.

Source: http://tribune.com.ng