Whenever the weather changes or we consume unhygienic food, the illness we fear most is typhoid. Often, a high fever persists for weeks, leaving the patient bedridden. To tackle this serious disease, the World Health Organization (WHO) has issued updated guidelines. Significant changes regarding medicines and vaccines have occurred since 2018; older medicines are becoming less effective against the bacteria, while new vaccines have yielded promising results. Consequently, the WHO has revised its policies, making it clear that the strategy for combating the disease must change.
How the disease spreads and the extent of its impact
Typhoid is not a common viral fever; it is a dangerous infection caused by the Salmonella Typhi bacterium. The disease is directly linked to our daily hygiene and dietary habits.
- Consuming contaminated or unboiled water and eating unhygienic food sold in the open allows the bacteria to enter the digestive system.
- Some individuals appear completely healthy yet harbor the live bacteria in their bodies; these are known as “chronic carriers” who, knowingly or unknowingly, continue to infect others for years.
- According to estimates, approximately 6.2 million people worldwide contracted this fever in 2023 alone, resulting in over 70,000 deaths.
- Its impact is most severe in impoverished regions of South Asia (including India) and Africa, with children bearing the brunt of the disease.
Three major typhoid vaccines
| Vaccine | Age Group | Key Feature |
|---|---|---|
| TCV | 6 months+ | Long-lasting protection |
| Vi Polysaccharide | 2 years+ | Booster dose may be required |
| Ty21a | 6 years+ | Oral capsule; not suitable for everyone |
Symptoms may seem common, but ignoring them can be fatal
Once the bacteria enter the bloodstream through the intestines, the patient’s condition typically begins to deteriorate within one to two weeks. A persistent high fever that does not come down easily.
Abdominal cramps, severe pain, and a feeling of extreme weakness.
Severe headache accompanied by vomiting, diarrhea, or complete constipation.
If timely and appropriate treatment is not received, intestinal ulcers and bleeding can occur; in some cases, the intestine may even rupture, posing a direct threat to life.
Why are medicines becoming ineffective?
The biggest challenge doctors currently face is that the typhoid bacterium has become highly resistant; older antibiotics—which once enabled patients to recover and get back on their feet within two days—are now proving ineffective for many patients.
Multidrug-resistant and XDR (extensively drug-resistant) bacteria have spread rapidly across South Asian countries.
In many instances, even new and expensive medications fail to work.
Given this threat, the WHO emphasizes that getting vaccinated has become far more important than relying solely on pills and syrups.
Which vaccine is the best?
While three types of vaccines are available on the market, the WHO has highlighted the TCV (Typhoid Conjugate Vaccine) as the most effective option in its report.
TCV Vaccine: This is the most modern vaccine available today. It is formulated with a specific protein, enabling it to generate robust immunity in everyone from infants as young as six months old to adults aged 45 to 65.
Vi Polysaccharide Vaccine: This injection is administered to children over two years of age; however, its effectiveness begins to wane after two or three years, necessitating a booster shot.
Ty21a Capsule: This is an oral medication given to children over six years of age, but it is not suitable for pregnant women or individuals with compromised immune systems. What the new research data reveals
Large-scale trials of the TCV vaccine have been conducted on hundreds of thousands of children in countries such as Nepal, Bangladesh, and Malawi. These studies have yielded several highly significant findings.
This new vaccine has been found to be 80% to 85% effective in protecting against typhoid.
In children vaccinated at a slightly older age—around five years old—the protection remained robust for several years.
While immunity may wane slightly after a few years in younger children, the vaccine still provides protection against severe disease.
It has also proven to be completely safe; analysis of data from hundreds of thousands of individuals showed no major risks, with only mild pain or low-grade fever observed—symptoms that resolve on their own.
Convenience of co-administration with other vaccines
Parents often worry about whether the typhoid vaccine can be administered alongside other routine vaccines. The report clearly states that:
TCV can be administered on the same day as the Measles-Rubella (MR) vaccine without any adverse effects.
It is safe for children living with HIV or those with compromised immune systems, although medical supervision is required in such cases.
No adverse effects on the child have been observed even if a woman inadvertently receives the vaccine during pregnancy.
WHO’s direct message to countries
The key takeaway from this report is that to defeat typhoid, countries must mandatorily incorporate TCV into their vaccination policies.
In regions with a high burden of typhoid, children should receive the vaccine as early as nine months of age, and large-scale campaigns should be conducted for all children up to 15 years old.
A booster dose may be administered after a few years if necessary.
