This article appears in The Star Health on January 18, 2015.
Water-related infections are common. According to the World Health Organisation (WHO), it causes 4% of all deaths and 5% of disabilities annually.
An estimated 2.2 million people die annually from gastrointestinal infections, the majority of whom are children in developing countries. This is because of limited or no access to safe water, insufficient sanitation and poor hygiene.
The water-related infections may be sanitation- and hygiene-related or vector-borne diseases associated with water.
Adequate sanitation – toilets and latrines – allows appropriate disposal of human waste, which breaks the infection cycle of many diseases.
Hygiene refers to acts that promote good health and cleanliness, e.g. frequent hand washing, face washing, and bathing with soap and clean water.
Water plays an important role in the spread of insect-borne diseases because many insects, e.g. mosquitos, breed in water. An increase in water impacts directly on the number of mosquitoes and other insects that breed in water. Bites from infected insects transmit disease to humans, e.g. malaria and dengue fever.
According to the Health Ministry, the incidence in 2013 of food poisoning, typhoid, cholera, hepatitis A and dysentery were 47.79, 0.73, 0.58, 0.41 and 0.28 per 100,000 of the population respectively.
The mortality rate of food poisoning and typhoid were 0.04 and 0.01 per 100,000 of the population respectively.
Certain infectious and parasitic diseases are the third most common cause of hospital admissions (9.4%), and also, the third most common cause of hospital mortality (13.66%) in 2013.
There are numerous water-related infections. The causes include bacterial sources (e.g. E. coli, Salmonella sp, Shigella sp, Campylobacter sp, Vibrio cholerae, Leptospira sp); viral (e.g. hepatitis A, enteroviruses, rotaviruses, dengue); parasitic (e.g. Entamoeba histolytica, Plasmodium sp, Giardia sp, Filarioidea, hook worm, helminth); chemical (e.g. arsenic, copper, lead); and other diseases, contaminants and injuries (e.g. marine toxins, ringworm, tinea).
When there are natural disasters such as floods or earthquakes, access to safe water, adequate sanitation and hygiene are compromised.
Flood and stationary water pose various health risks. They may contain potentially dangerous materials, e.g. sewage, agricultural materials and industrial chemicals.
Exposure to flood waters can also cause infections or injuries. Buildings that have been damaged by or exposed to flood waters may also pose health risks from chemicals, electrical hazards and displaced animals or their carcasses.
Diarrhoea, which is the passage of loose or liquid stools more frequently than is normal, is a common symptom of many water-related infections, especially gastrointestinal infections. The diarrhoea may be watery (e.g. rice-water stools in cholera) or blood stained (e.g. dysentery). The duration of the diarrhoea may be a few days or several weeks.
Vomiting is another common symptom of gastrointestinal infections. Abdominal pain may be present in some cases.
Severe or persistent diarrhoea or vomiting, with its increased loss of body fluids and consequent dehydration, may be life-threatening in children and people who have poor immunity or are malnourished.
The features of dehydration include dry skin, dry mouth, thirst and feeling faint.
Leptospirosis, which is acquired skin, mucosa or conjunctival contact with water or soil contaminated with the urine of rodents, carriers or diseased animals, presents with varied features, making diagnosis difficult.
There may be a mild, influenza-like illness; jaundice, kidney failure, haemorrhage and myocarditis with heart rate abnormalities; meningitis or meningoencephalitis; and lung haemorrhage with respiratory failure.
Some of the infections are self-limiting and do not require treatment. Others, particularly those that are severe or persistent, have to be treated with the appropriate medicines and the dehydration corrected.
The primary measures to address water-related infections include providing access to safe drinking water, improved sanitation, promoting good personal and food hygiene, and health education about how infections spread.
The primary measures to address loss of body fluids include consuming more fluids than usual, including oral rehydration salts solution, to prevent dehydration; continue feeding; and seeking medical assistance when the diarrhoea or vomiting is persistent or severe, there are signs of dehydration or there are other complaints.
In short, anyone in flood-affected areas are well advised to seek early medical attention if they feel unwell.
The public health response has several challenges. They have to address the health risks of flood and stationary waters, and that from damaged buildings. Health education is crucial.
Other essential measures include the provision of emergency water and electrical supply; medical and health services; and communication facilities to the affected areas.
These responses have to be rapid and effective if control and prevention of the spread of diseases is to be kept to a minimum.
Dr Milton Lum is a member of the board of Medical Defence Malaysia. This article is not intended to replace, dictate or define evaluation by a qualified doctor. The views expressed do not represent that of any organisation the writer is associated with.