Common Infectious Diseases in Malaysia During the Flood Season

Caused by infection of the intestine with vibrio cholerae bacteria, cholera is primarily a diarrheal illness that occurs when humans consume contaminated food or water. This diarrheal infection often demonstrates mild symptoms but can escalate with severe and life-threatening symptoms—for example, shock and seizures.

Hepatitis is essentially a family of viral diseases that appears in the form of liver inflammation that affects liver functions acutely, or even chronically. Hepatitis A is particularly spread via the consumption of food and water contaminated with faecal matter.

It is common in areas of poor sanitation and victims exhibit fever, jaundice, and diarrhoea. Unfortunately, approximately 15% of Hepatitis A victims experience prolonged symptoms for over 6 to 9 months. Fortunately, this disease has a working vaccine that can be administered to members of the public.

Dysentery is caused by a few types of bacteria and parasites. The bacteria shigella that causes dysentery can spread through contaminated food or water. A key symptom of the disease is bloody diarrhoea. However, many cases also manifest symptoms of abdominal pain, fever, cramps and malaise (feeling of discomfort, illness, or unease).

Leptospirosis is a bacterial disease caused by the genus Leptospira. Leptospirosis outbreaks are common in regions that experience recurrent flooding. In fact, leptospirosis infection mainly occurs via contact with water or food contaminated by animal urine.

Its symptoms are mainly high fever, incessant headache, vomiting, jaundice, and diarrhoea. If left untreated, the disease can quickly result in kidney damage, meningitis, liver failure, or respiratory distress. However, fatality rates are relatively low.

Dengue fever is a common infectious disease caused by ribonucleic acid (RNA) virus from the flaviviridae family transmitted via mosquito vectors known as Aedes aegypti.

As a viral disease associated with urban environments, dengue fever manifests as a sudden onset of fever and severe headache. In some instances, it occasionally produces shock and haemorrhage, leading to death in approximately 5% of cases.

Malaria is a common infectious disease caused by single-cell parasitic protozoa called plasmodium that is transmitted to humans through the bite of a female Anopheles mosquito.

As a result, plasmodium parasites multiply in the human liver and attack the red blood cells, and this leads to fever cycles and sporadic sweating accompanied by anaemia. If left untreated, malaria often leads to death or damage to vital organs due to the interruption of blood supply to the brain.

Japanese encephalitis is essentially a viral brain infection spread through mosquito bites and common in rural areas in southeast Asia. The virus is mainly found in pigs and birds but is passed to mosquitoes when they bite infected animals.

If left untreated, the mosquito-borne disease (spread by culex tritaeniorhynchus mosquito) can progress to paralysis, coma, and even death.

Conjunctivitis is a minor infection that manifests as pinkeye. As an inflammation of the conjunctiva (the white eye component and the inner eyelids), conjunctivitis causes irritation and can be caused by bacterial or viral infection.

Measles is fundamentally an acute viral respiratory illness characterised by a prodrome of fever, cough, total body rash and conjunctivitis. By nature, measles is a very contagious respiratory infection that spreads through the air by respiratory droplets as an infected individual coughs or sneezes.

Since infectious diseases are easily spread through food and water, it is imperative to ensure access to safe water for and hygienic food during the floods. This can be the first line of defence against a potential infectious disease outbreak.

Relatedly, personal hygiene is a significant component of infectious disease prevention during flooding seasons. Frequently wash hands with soap and clean water or use alcohol-based hand sanitisers (consisting at least 60% alcohol).

Poor sanitary conditions can easily escalate infectious disease spread. For example, leptospirosis outbreaks typically occur through rodent urine contaminating water. Generally, unsanitary conditions can foster rodent breeding.

As such, it is vital to ensure that your surroundings are constantly kept clean following the occurrence of a flood.

Try to clear stagnant water to prevent the breeding of mosquitos. Furthermore, sleep under mosquito nets, use mosquito repellents and even residential window screens to reduce exposure to mosquitoes that are disease vectors during flood seasons.