Typhoid Fever
Typhoid is a bacterial infection caught by swallowing water or food contaminated with sewage. The fever builds step by step over about a week rather than spiking and breaking, and it comes with headache, aching, poor appetite, abdominal pain, and constipation more often than diarrhoea in adults. It is diagnosed by a blood culture, which must be taken before the first dose of antibiotic; the Widal test that is still ordered everywhere in Pakistan is unreliable in both directions and cannot confirm or exclude typhoid on its own. Since an outbreak that began in Hyderabad in 2016, an extensively drug-resistant strain — XDR typhoid — has spread across the country. It does not respond to the antibiotics most commonly bought over a pharmacy counter, including cefixime tablets and ceftriaxone injections, which is why so many courses fail. Azithromycin is the usual oral option for uncomplicated XDR typhoid and a carbapenem such as meropenem is used for severe illness, but the choice belongs to the doctor holding the culture result. Fever takes four to seven days to settle even on the correct antibiotic, and stopping when it does is how relapse and resistance happen. Two things prevent typhoid: the typhoid conjugate vaccine, given free in Pakistan's routine immunisation schedule at nine months, and water that has been boiled or properly filtered.
Health writers · Aslam Clinic
What typhoid is
Typhoid fever is an infection with the Salmonella Typhi. It is spread by the faecal-oral route: bacteria from the stool of an infected person reach someone else's mouth, almost always through drinking water or food washed or prepared with it. A closely related organism, Salmonella Paratyphi, causes a milder illness called paratyphoid; the two together are called enteric fever.
Once swallowed, the bacteria cross the wall of the small intestine and enter the bloodstream, which is why typhoid is a whole-body illness rather than a stomach upset. Symptoms begin six to thirty days after exposure, most often around a week to two weeks, and that long and variable gap is why people rarely connect the illness to any particular meal.
The setting explains the burden. Where a piped supply runs intermittently, pressure drops and sewage is drawn into the pipes. Where a supply line runs alongside a broken drain, the two mix. After flooding, both happen at once. Pakistan has one of the highest typhoid rates in the world for reasons that are about infrastructure rather than about individuals.
How it feels, week by week
The classical description is of an illness that unfolds rather than arrives. Antibiotics given early cut it short, so the full picture below is what happens when the diagnosis is missed or the drug does not work — which, with drug-resistant strains, is now more common than it should be.
- First week. Fever that rises a little higher each day, often reaching 39 to 40 degrees Celsius by the end of the week and staying up rather than breaking with sweats. Persistent headache, aching, tiredness, poor appetite and a dry cough. The abdomen feels bloated and tender. Adults are usually constipated at this stage; children more often have diarrhoea.
- Second week. The fever plateaus high. The person becomes withdrawn and exhausted, eats almost nothing, and looks unwell in a way that alarms the family. The tongue is coated with red edges. The spleen and liver may enlarge, are often mildly abnormal, and occasionally the liver is inflamed enough to cause . Faint pink spots may appear on the trunk, though they are very hard to see on brown skin. The pulse is often slower than the height of the fever would suggest.
- Third week. Without effective treatment this is when complications appear: bleeding from the intestine, perforation of the bowel, and confusion or delirium. This is the week in which typhoid kills.
- Fourth week onwards. In those who recover, the fever gradually settles and strength returns slowly over several weeks. Around one person in ten who is untreated has a relapse a week or two after apparent recovery.
How it is diagnosed, and the test that misleads
This section matters more in Pakistan than almost anything else in the article, because the wrong test is ordered constantly and acted upon confidently.
| Test | What it does | How much to trust it |
|---|---|---|
| Blood culture | Grows the bacteria from a blood sample and then tests which antibiotics still kill it | The only test that confirms typhoid, and the only one that reveals resistance. Positive in roughly half of cases when taken in the first week and before any antibiotic. A single dose of antibiotic beforehand can turn it negative |
| Widal test | Measures antibodies against the bacterium | Unreliable in Pakistan and over-used. It rises after past infection and after vaccination, and it is often still negative in the first week when it is most needed. A single Widal cannot confirm or exclude typhoid |
| Typhidot and other rapid IgM tests | Detect antibodies within hours | Faster than Widal and somewhat better, but they still produce both false positives and false negatives. Useful as support, never as proof, and they say nothing about which antibiotic will work |
| Bone marrow culture | Grows the bacteria from marrow | The most sensitive test, and stays positive even after antibiotics have started. Uncomfortable, so reserved for difficult cases |
| Stool and urine culture | Grows the bacteria from stool or urine | More useful in the second and third weeks, and the way chronic carriers are identified |
| Not diagnostic on its own | Typically shows a normal or low , which points away from an ordinary bacterial infection and can support the suspicion |
Extensively drug-resistant typhoid
In November 2016 an outbreak began in Hyderabad, Sindh, caused by a strain of Salmonella Typhi that had acquired resistance to almost everything used against it. It has since been reported from every province of Pakistan and exported to other countries by travellers. It is called extensively drug-resistant, or XDR, typhoid, and it is now the working assumption in much of the country until a culture says otherwise.
| Strain | Not killed by | Usually treated with |
|---|---|---|
| Drug-susceptible | Nothing in routine use | Several options remain, chosen on the culture report |
| MDR (multidrug-resistant) | Ampicillin, chloramphenicol, cotrimoxazole | A fluoroquinolone where it is still active, or a third-generation cephalosporin such as ceftriaxone or cefixime |
| XDR (extensively drug-resistant) | All of the MDR three, plus fluoroquinolones such as ciprofloxacin and ofloxacin, plus third-generation cephalosporins including ceftriaxone injections and cefixime tablets | Azithromycin for uncomplicated illness. A carbapenem such as meropenem, given in hospital, for severe or complicated illness |
The practical consequence is the reason this section exists. A three-day or five-day course of ceftriaxone injections, bought privately and given at home, is one of the commonest treatments for fever in Pakistan — and against XDR typhoid it does nothing except delay effective treatment and select for further resistance. If a fever has not begun to settle after four or five days of an antibiotic, the answer is a culture and a rethink, not a longer course of the same thing.
Azithromycin resistance has now also been reported, in small but real numbers. That is the whole argument for culture-guided treatment and for not using antibiotics for fevers that do not need them: the number of drugs left is finite, and it is shrinking.
Treatment
- Antibiotics, chosen on the culture. Most uncomplicated XDR typhoid is treated with oral azithromycin; severe or complicated illness is treated in hospital with a carbapenem. The dose and the length of the course depend on the drug, the weight and the severity, and are set by the prescriber.
- Expect the fever to take four to seven days to settle, even when the antibiotic is exactly right. This is normal in typhoid and is not a sign of failure. Judging an antibiotic by day two is how people end up on their third unnecessary drug.
- Complete the full course. Stopping when the fever goes is the main cause of relapse, and relapse is usually harder to treat than the original illness.
- Paracetamol for the fever, at the usual doses, with tepid sponging. are best avoided where there is abdominal pain, because of the risk of intestinal bleeding.
- Fluids and food. Small frequent meals of soft, easily digested food, and enough fluid to avoid and keep passing pale urine. There is no need for a bland restricted diet beyond what is comfortable.
- Rest, and no heavy work for two weeks after the fever settles. The bowel wall is fragile during recovery and perforation can occur after the fever has gone.
- Admission is needed for persistent vomiting, severe abdominal pain, confusion, bleeding, very high fever with a low blood pressure, pregnancy, or an infant.
Carriers
Around two to five people in every hundred who recover from typhoid become carriers: they go on holding the bacteria in the gallbladder and shedding them in the stool for a year or more without ever being ill. Chronic carriers are more common in women, in older people, and in those with gallstones. A carrier who prepares food for others can sustain an outbreak on their own, which is why food handlers who have had typhoid should be tested before returning to work, and why anyone with recurrent unexplained typhoid in the household should be investigated. Carriage can usually be cleared with a prolonged antibiotic course, and occasionally needs the gallbladder removed.
Prevention: the vaccine and the water
Pakistan was the first country in the world to introduce the typhoid conjugate into its routine programme, beginning in Sindh in 2019 and extending nationally afterwards, precisely because of the XDR outbreak. It is given free as a single injection at nine months of age alongside the measles vaccine, with catch-up campaigns covering children up to fifteen years. It works in infants, which the older typhoid vaccines did not, and protection lasts for years rather than months.
- Check the vaccination card. If a child under fifteen has not had the typhoid conjugate vaccine, ask at the nearest EPI centre. It costs nothing.
- Boil drinking water for one minute at a rolling boil, or use a filter certified to remove bacteria, or chlorinate it correctly. A cloth over the pot is not a filter.
- Store treated water in a covered container with a tap or a dedicated ladle, so hands do not go into it.
- Ice, cut fruit, sugarcane juice and cold drinks made with tap water carry the same risk as the water itself. Ice is the commonly forgotten one.
- Wash hands with soap after using the toilet and before preparing food, and make sure children do. Ash or mud is not soap.
- Eat food hot and freshly cooked. Food that has stood at room temperature, and raw salad washed in untreated water, are the usual culprits.
- During and after flooding, assume the supply is contaminated and treat all water, including for brushing teeth.
When to see a doctor
See a doctor for any fever that has lasted three days or more and is not clearly settling, and sooner if there is abdominal pain, persistent headache, or a child who has stopped eating and playing. Ask for a blood culture before any antibiotic is started. During the post-monsoon months a fever needs both typhoid and dengue considered, because the early symptoms overlap and the treatment for each is quite different.
Go back sooner than the follow-up appointment if the fever has not begun to fall after five days of treatment, if abdominal pain becomes severe, if the stool turns black, or if the person becomes confused or unusually drowsy. Go to an emergency department for sudden severe abdominal pain with a rigid abdomen.
Common questions
Still not sure what to do?
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