Cholera

Introduction

Cholera is an acute diarrhoeal disease caused by Vibrio cholerae. Humans are the only known natural hosts. V. cholerae is endemic in many low-income countries and is usually associated with poverty, poor sanitation and poor access to clean drinking water.

Risk for travellers

The overall risk of cholera for travellers is extremely low, such that it is 0.2 cases per 100,000 travellers. However, for long term travellers in areas of outbreaks the rate may be as high as 500 cases per 100,000 travellers. Activities that may predispose travellers to infection include: drinking untreated water, eating poorly cooked seafood in endemic areas, or travellers living in unsanitary conditions, for example relief workers in disaster or refugee areas.

Transmission

Cholera is mainly transmitted via the faecal- oral route, most importantly by consumption of contaminated water and, to a lesser degree, food. However, direct person to person transmission is rare.

Signs and symptoms

The usual incubation period is 2 to 5 days, although it can be as short as several hours. Cholera may not present with any symptoms, or can be mild in healthy individuals, with the only symptom being diarrhoea. Severe cholera is characterised by a sudden onset of profuse, watery diarrhoea that is usually accompanied by nausea and vomiting, If this is left untreated, it can result in serious dehydration, electrolyte imbalance and circulatory collapse. Over 50% of the most serious cases die within a few hours, however, with prompt and effective treatment the mortality is less than 1%.

Treatment

Rapid fluid replacement with a balanced solution of sugar, electrolytes and water (oral rehydration salts) should be started urgently. In serious dehydrated cases, intravenous administration may be necessary. Individuals may also be treated with a course of antibiotics in order to improve symptoms and decrease the intestinal excretion of the organism. Patients who are treated promptly should respond quickly and recover.

Prevention

Advice on food and water hygiene precautions is the most appropriate prevention strategy for the majority of travellers. An oral cholera vaccine is available in the UK and can be offered to humanitarian aid and relief workers and travellers with remote itineraries in areas of cholera outbreaks who have limited access to safe water and medical care.

If you would like advice or require the cholera vaccine please book an appointment with our trained and knowledgeable pharmacist.