What is cholera?
Cholera is a highly contagious bacterial infection of the bowel caused by eating food or drinking water contaminated with the bacterium Vibrio cholerae.
The infection can be asymptomatic (no obvious symptoms) to severe or life threatening. The most common symptom is severe continued watery diarrhea. Vomiting may occur in the early stages for a few hours. Fever is rare.
Most people reported to have cholera have had a history of traveling to a cholera affected area. Symptoms may take up to 2-5 days to appear and it’s life-saving to start re-hydrating as soon as possible and at least within 3-4 hours.
Cholera is an ‘urgent notifiable condition’ which means doctors and pathologists need to report a diagnosis of cholera by telephone to the Australian government health authorities.
All cases of cholera are to be reported to The World Health Organization (WHO) and nearby countries by the Australian Government Department of Health and Ageing.
How is cholera caused or transferred?
Cholera usually occurs by a person consuming food or water exposed to faecal contamination. Higher risks include eating undercooked seafood from coastal waters, drinking inadequately treated water or adding contaminated ice to drinks. Places with poor sanitation are higher risk areas.
It is rare for cholera to be transferred from one person to another.
Transfer only occurs between people from the ingestion of water or food containing the cholera bacteria due to inadequate handwashing and cleanliness.
Cholera bacteria can persist in an infected person’s faeces for seven to 14 days.
Who is most at risk of Cholera?
Individuals most at risk when exposed to cholera are:
- children;
- elderly;
- suffers of gastric achlorhydria (low or no acid in the stomach);
- breastfeeding mothers; and
- individuals in regions of unsafe drinking water, unclean hygiene and inadequate sanitation.
Complications
The table shows the possible severity of symptoms when the condition worsens:
Cholera symptoms and of level of severity |
||
Low risk |
Moderate risk |
High risk |
Abdominal pain – loss of appetite, constipation, diarrhea, nausea and vomiting
Coughing – airway pain and shortness of breath Lack of concentration – fatigue, hyperactivity, headache, sweating, dizziness, weakness and impaired coordination Other problems – fever, polyuria (excessive urination), muscle pain, pruritis (itchy skin), ocular (eye) pain and irritation. |
Severe abdominal pain – diarrhea, melena(blood in faeces) and vomiting
Chest pain – pain when taking a deep breath, weakness with breathing, wheezing and shortness of breath Altered alertness – confusion, hallucination, blurred vision, seizure, muscle rigidity, slurred speech and fainting Abnormal heart conditions – bradycardia (slow heart rate), tachycardia (fast heart rate), chest pain, hypertension (high blood pressure) and hypotension (low blood pressure) |
Excruciating abdominal pain (from haemorrhage or perforated gut)
Coma – paralysis and seizure Lethal heart conditions – severe bradycardia, severe tachycardia, respiratory arrest and cardiac arrest Discoloured skin – bluish grey skin and oedema (swelling) Changes in urine production – oliguria (low urine output) and anuria (severe reduction of urine) |
Adapted from: TABLE: Signs and symptoms by severity category (Modelled after Persson et. al.,1998 and includes SPIDER database elements).
Tests and diagnosis
The diagnosis of cholera requires a specialist laboratory test of faecal specimen to identify the bacteria.
Treatment
Immediate treatment is required as cholera can worsen within hours.
The treatments depend on the severity of the symptoms:
- drinking oral rehydration solutions (ORS) containing fluid and salts;
- intravenous rehydration;
- antibiotics (although cholera can be antibiotic resistant); and
- zinc combined with cholera vaccine (containing recombinant cholera toxin B subunit).
Prevention
The World Health Organization (WHO) recommends focusing on prevention of cholera with adequate handwashing, safe water and food precautions.
The oral killed whole cell B subunit vaccine may be appropriately recommended for travellers if the region considered for entry is a high risk area (oral solution).
Simple measures to avoid getting cholera include:
- avoiding ice in drinks;
- using bottled water for drinking, brushing teeth, washing your face and hands;
- eating foods that have been thoroughly cooked and are still hot, and
- only eating meat and seafood if well cooked.
Call your General Practitioner immediately if you have been in a high risk area and have developed diarrhea and/or some vomiting.
Last Updated: March 25, 2021