Typhoid fever is a serious bacterial infection caused by Salmonella enterica serotype Typhi. It remains a major health problem in places with inadequate sanitation and unsafe water, and it causes substantial illness and deaths around the world. In this detailed guide, you will learn how typhoid spreads, how the vaccines work, which type to choose, how well each one protects, and what side effects to expect.
What Is Typhoid Fever?
Typhoid fever spreads through food and water contaminated with the feces of an infected person. You catch it by eating or drinking something that carries the bacteria. Some people carry the bacteria in their body for a long time without feeling ill and can spread it to others.
Symptoms
Typhoid usually builds up slowly over one to three weeks:
- A fever that rises step by step, up to 39°C to 40°C
- Weakness, tiredness, and headache
- Stomach pain, and constipation or diarrhea
- Loss of appetite
- A rash of small, flat, rose-colored spots in some people
Complications
Without treatment, typhoid can cause bleeding or a hole in the intestine, infection of the blood, and death. Doctors treat it with antibiotics, but drug-resistant strains are a growing problem. Extensively drug-resistant (XDR) typhoid has caused large outbreaks in Pakistan, which makes prevention and vaccination more important.
History of the Typhoid Vaccine
Typhoid vaccines go back to the late 1800s. In 1896, Almroth Edward Wright developed one of the first typhoid vaccines using heat-killed bacteria. These early vaccines gave some protection but often caused strong side effects. Modern vaccines are safer and work better.
Types of Typhoid Vaccine
1. Typhoid Conjugate Vaccine (TCV)
This injectable vaccine is the newest and most effective. It links a part of the bacteria (the Vi polysaccharide) to a carrier protein, which helps even babies build strong, longer-lasting immunity.
- Age: Babies from 6 months of age, children, and adults
- Doses: One dose
- Protection: About 80 to 90 percent
- Recommended by: The World Health Organization (WHO)
Pakistan has used TCV in mass vaccination campaigns in Sindh and Punjab against drug-resistant typhoid.
2. Vi Polysaccharide Vaccine
This injectable vaccine is for people aged 2 years and older.
- Doses: One dose
- Booster: About every 2 to 3 years if the risk continues
- Protection: About 50 to 70 percent
It does not work well in babies and young children.
3. Oral Vaccine (Ty21a)
This live vaccine comes as capsules that you swallow.
- Age: 6 years and older
- Doses: Four capsules, taken on alternate days, usually one hour before a meal
- Booster: About every 5 years
- Protection: About 50 to 80 percent
It is not available in every country, and people with weak immune systems should not take it.
How Well Do They Work?
- Conjugate vaccine: Protects about 80 to 90 percent of people, and protection lasts longer.
- Vi polysaccharide vaccine: Protects about 50 to 70 percent of people.
- Oral vaccine: Protects about 50 to 80 percent of people.
No typhoid vaccine protects against everything, and no vaccine protects against other types of Salmonella. Good hygiene remains essential.
Who Should Get a Typhoid Vaccine?
- Children in areas where typhoid is common
- Travelers to places where typhoid is common, such as South Asia, parts of Africa, and Southeast Asia
- People who live with someone who carries the bacteria
- Laboratory workers who handle the bacteria
- People in outbreak areas
Ask your doctor which vaccine and schedule suit you. Travelers should get vaccinated at least one to two weeks before they leave.
Side Effects
- Pain, redness, or swelling where you had the shot
- Mild fever
- Headache and tiredness
- Muscle aches
- Stomach upset with the oral vaccine
Most side effects last a day or two. Serious allergic reactions are rare. Seek help right away if you have trouble breathing or swelling of the face.
Who Should Not Get It?
- People who had a severe allergic reaction to a previous dose or to any ingredient
- People with a moderate or severe illness, until they recover
- People with weak immune systems, pregnant women, and anyone taking antibiotics should not take the live oral vaccine
Doctors may use the injectable vaccines in pregnancy if the risk of typhoid is high. Ask your doctor.
How Is Typhoid Treated?
Doctors treat typhoid with antibiotics such as azithromycin, ceftriaxone, or, for resistant cases, stronger antibiotics. Do not take antibiotics without a doctor’s advice. Early treatment prevents complications.
How Else to Prevent Typhoid
- Drink safe, boiled, or bottled water.
- Eat food that is cooked and served hot.
- Wash your hands with soap before eating and after using the toilet.
- Avoid street food, ice, and raw salads when you are unsure about hygiene.
- Peel fruit yourself.
- Wash utensils with clean water.
- Improve sanitation and clean water supplies in your community.
Typhoid in Pakistan
Typhoid is a major health problem in Pakistan, where unsafe drinking water and poor sanitation are common. Since 2016, a strain resistant to most common antibiotics has spread in Sindh and other areas. Doctors call it extensively drug-resistant (XDR) typhoid. It does not respond to ampicillin, chloramphenicol, co-trimoxazole, ciprofloxacin, or ceftriaxone, and doctors must use stronger antibiotics such as azithromycin or carbapenems. This makes vaccination one of the most useful tools to protect children.
Typhoid Carriers
A small group of people carry typhoid bacteria in their gallbladder for months or years after they recover, and they may feel completely well. These carriers can spread the bacteria through food they prepare. This is why food handlers must wash their hands carefully and why doctors test people when typhoid cases appear in a household.
How Doctors Diagnose Typhoid
- Blood culture: This is the most reliable test. It needs a blood sample taken before you start antibiotics, and results take a few days.
- Rapid tests: Tests such as Typhidot give quick results but can be less accurate.
- Widal test: It is widely used, but it can give false results, so doctors do not rely on it alone.
- Stool or bone marrow culture: Doctors use them in difficult cases.
Do not start antibiotics on your own. Treatment without a test can hide the cause and lead to resistance.
Typhoid Vaccine Schedule at a Glance
- Typhoid conjugate vaccine (TCV): one injection from 6 months of age
- Vi polysaccharide vaccine: one injection from 2 years of age, repeated every 2 to 3 years
- Oral Ty21a vaccine: four capsules on alternate days from 6 years of age, repeated every 5 years
Can Typhoid Vaccine Be Given With Other Vaccines?
Yes. Doctors can give the typhoid conjugate vaccine at the same visit as other routine childhood vaccines, such as measles vaccine, in a different arm or leg. Ask your pediatrician about the best schedule for your child.
Typhoid in Children
Children can get typhoid at any age, and young children may have milder or unusual symptoms, such as long fever or diarrhea. Doctors advise vaccination in areas where typhoid is common, and they advise safe water, handwashing, and cooked food at home. Never give aspirin to a child with fever. Take your child to a doctor if the fever lasts more than three days.
Common Myths About the Typhoid Vaccine
- “Once I had typhoid, I cannot get it again.” You can get it again, so the vaccine still helps.
- “The vaccine makes my child sick.” It usually causes only a sore arm or a mild fever for a day.
- “Boiled water is enough.” Boiled water helps, but food handling and handwashing matter too.
Travel Advice
If you travel to a place where typhoid is common, get vaccinated at least one to two weeks before you leave. Even after vaccination, drink bottled or boiled water, avoid ice, eat food that is cooked and served hot, and wash your hands before eating. Seek medical help if you develop a fever during or after your trip.
Recovery and Follow-Up
Most people with typhoid feel better within a few days of starting the right antibiotic, but full recovery can take weeks. Rest, drink plenty of fluids, and eat soft, nutritious food. Complete the whole antibiotic course. Return to the doctor if the fever comes back, if you have severe stomach pain, or if you notice black stools. Children and food handlers may need a stool test before they return to school or work.
Pregnancy and Breastfeeding
Typhoid in pregnancy is serious. If you live in or travel to a high-risk area, ask your doctor about vaccination. Breastfeeding mothers can receive the injectable vaccines, and the baby continues to feed normally.
Frequently Asked Questions
How many doses of the typhoid vaccine do I need?
The conjugate vaccine needs one dose. The Vi vaccine needs one dose and a booster every two to three years. The oral vaccine needs four capsules.
Which typhoid vaccine is best?
The typhoid conjugate vaccine, because it works best and lasts longer. It also suits babies.
Can I get typhoid after the vaccine?
Yes, but it is less likely and usually milder.
Is the typhoid vaccine safe for children?
Yes. The conjugate vaccine is safe from 6 months of age. Ask your pediatrician.
When should I get the typhoid vaccine before travel?
At least one to two weeks before you leave.
Disclaimer: This article is for information only. It is not medical advice. Please talk to your doctor about your own health.