Enteric Fever

Overview of Enteric Fever

Enteric Meaning in Urdu

ٹائیفائیڈ بخار ایک عام بیماری ہے جو کہ زیادہ تر ترقی پذیر ممالک میں لوگوں کو متاثر کرتی ہے۔ اس بیماری کی وجہ سے کمزوری، معدے کے درد، سر درد، قبض، اسہال، کھانسی، اور بھوک کی کمی کا سامنا کرنا پڑ سکتا ہے۔ عام طور پر ٹائیفائیڈ گندہ پانی پینے یا خوراک کھانے کی وجہ سے لاحق ہوتا ہے۔ اس بیماری کی وجہ سے تیز بخار کا بھی سامنا کرنا پڑتا ہے جس کی وجہ سے کچھ لوگوں کو ڈی ہائڈریشن کا بھی سامنا کرنا پڑتا ہے، اس لیے ٹائیفائیڈ لاحق ہونے کی صورت میں پانی کو زیادہ استعمال کرنے کا مشورہ دیا جاتا ہے۔

Enteric fever is a systemic illness (affects the whole body) caused by the bacteria, Salmonella enterica. The illness occurs by ingesting contaminated food or drinking water and spreading through human carriers. It is an acute form of illness characterized by fever, diarrhea, and vomiting and can sometimes be fatal.
The commonly known name used for enteric fever is, “Typhoid fever”. Enteric fever refers to both types; typhoid fever and paratyphoid fever.  Enteric fever means in Urdu is, ‘آنت بخار’.

Occurrence

It is distributed around the globe but its occurrence is more in developing countries with unhygienic conditions especially in children. Enteric fever or typhoid has the highest incidence in Asia, according to the ‘Surveillance Report on Typhoid Fever Epidemiology”.
According to a report by ‘Infection Landscapes’, Enteric fever is putting more burden than cholera worldwide. It affects more than 22 million people with 200,000 deaths per year. The fatality rate of untreated enteric fever is 1 in every 5 cases i.e. 20%.

Signs and Symptoms of Enteric Fever

The main symptoms of enteric fever are high fever and rashes. Symptoms include;

  • High fever (~104oF) for several days
  • Red-colored spots or rashes specifically on the abdomen and neck    
  • Malaise (body fatigue)
  • Headache
  • Stomach pains
  • Loss of appetite

The bacterium causing the enteric fever can live for days and multiplies in your body. However, symptoms may develop after 3 weeks of exposure to bacteria. Symptoms also resemble other illnesses, so always consult your general physician for a particular diagnosis.

Don’t confuse Enteric fever with Typhus!

Typhus is a vector-borne disease with a somewhat similar clinical presentation (signs and symptoms) to enteric fever, and even physicians would find difficulty in diagnosis based on symptoms alone. Nonetheless, both of these diseases are quite distinct from each other in terms of pathogenicity, cause, and mode of transmission.

Types of Enteric Fever

Causes of Enteric Fever

Enteric fever is caused by a gram-negative bacterium, Salmonella enterica. Another serovar, Salmonella typhi is responsible for causing typhoid fever while Salmonella paratyphi causes paratyphoid fever.

How are the bacteria transmitted?

The enteric fever bacteria are found in contaminated (polluted) places i.e. unhygienic food or impure water. Mostly, it is transmitted through fecal-oral routes. Drinking contaminated water, eating fish from sewage-polluted areas, raw fruits and vegetables from the soil fertilized by human excreta, and consuming contaminated dairy products. Flies may transfer the infectious agents from one place to another i.e. foods, and by consuming such food will lead you toward the infection.

Pathogenesis of enteric fever

Salmonella typhi enters through the mouth in the form of food and moves to the intestine where it stays for 1-3 weeks. Then, it goes into the bloodstream through the intestinal wall. It spread to various body organs through the bloodstream. Despite the body’s immune response, Salmonella typhi can live within the body, multiples there and affects the body's organs.  

The pictorial description of the route S. typhi pathogenesis is shown here.

Can animals spread enteric fever?

No! The bacterium causing enteric fever lives only in humans, so the disease is transmitted through direct human contact.

Happniness

Risk Factors of Enteric Fever

Happniness

Prevention

Practicing good hygiene will prevent you from getting the infection. You should consider the following points:

  • Use boiled or chemically disinfected water
  • Wash your hands and face with soap and water or alcohol-based sanitizer if water is not available
  • Properly wash raw fruits and vegetables before consuming them
  • Wash the surface of tins, bottles, and cans carrying the eatables
  • Avoid the use of raw meat
  • Use pasteurized milk
  • Do not eat food from open places restaurants
Happniness

Diagnosis

1. Medical and travel history

A doctor will ask you about your medical history, and travel history and suspect your symptoms.

2. Laboratory tests

Enteric fever is further diagnosed by laboratory tests to detect the presence of bacteria during the first week, which include the following:

A small sample of your blood, stool, urine, or bone marrow is taken to detect bacterial growth. Microscopy is performed for cultures. A bone marrow culture test is more sensitive for bacterial detection in enteric fever.

3. Widal test

This test looks for the antibodies produced by the person affected by enteric fever. S. typhi antigens are used to detect the presence of antibodies specific to S. typhi. Although the Widal test is affordable and convenient, there exist some concerns about its reliability.

WHO has shown concern about the Widal test!!

They recommended that not just relying on this antibody detection test, but using other diagnostic culture tests for authentic diagnosis.

The infection stages of enteric fever along with its diagnosis are tabulated here:

Time

Infection stage

Stool culture

Blood culture

Widal test

Week 1

Incubation

Positive

Negative

Negative

Week 2

Active invasion

Negative

80% positive

20% positive

Week 3

Disease

80% positive

Negative

50% positive

Week 4

Convalescence

50% positive

Negative

80% positive

Indefinite

Late

3% positive

Negative

80% positive

Treatment of Enteric Fever | When to Consult a Doctor

Antibiotic therapy is often recommended and is the only effective treatment for enteric fever. The antibiotics include; ciprofloxacin, azithromycin, and ceftriaxone.

Antibiotic resistance is a major problem in treating enteric fever, especially in developing countries. In this concern, vaccination for enteric fever can provide a good alternative to antibiotic therapy. 

Disclaimer! Please do not use any of these medicines on your own. Always consult your doctor for treatment. 

WHO and CDC have already alerted us that extensive drug resistance typhoid fever poses a serious public health concern.  

WHO recommended Vaccines

WHO currently recommended three vaccines to control the epidemic and endemic typhoid fever. These include:

  • Typhoid conjugate vaccine (TCV) – an injectable vaccine for children aged 6 months to adults of 45 years.
  • Vi antigen polysaccharide vaccine (Vi-PS) – an injectable vaccine for people aged 2 years and above
  • Attenuated Ty21a vaccine – an oral vaccine for above 6 years old people.

You need to know that symptoms may go away but bacteria may remain in your body. In this case, you remain a carrier for disease transmission. Avoid human contact as much as you can.

Be cautious! The illness could come again (relapse). Repeated tests can keep you out of danger that will confirm that enteric fever-causing bacteria are no longer in your body.

Please do not use any of these medicines on your own.