What you need to know about Rat Urine Disease (Leptospirosis)

Leptospirosis, also known as rat urine disease, is a infection caused by bacteria called Leptospira which stays in the blood. Humans get infected through contact with contaminated sources. The bacteria invades human tissues and organs, particularly affecting the livers and kidney.

Hiking and outdoor activities are considered high risk of exposure to leptospirosis. One may risk getting infected by coming into contact with contaminated water for example during river crossing, collecting water or playing by the waterfalls.

According to World Health Organisation (WHO) estimates1, 5-15% of untreated cases can progress to a more severe and potentially fatal stage. There have been two death cases in Malaysia over the past two months (June 2016 at the point of writing) and has prompt the Malaysian Health Ministry to issue a warning for general public awareness.

How Does One Get Infected?

Humans get infected through direct contact with water, food or soil that contain urine from the infected animals.

One can get infected by swallowing contaminated food and water or by coming to touch with contamination though exposed skin, eyes, nose and mouth. This means that we risk getting infected with leptospirosis when we swim or wade in contaminated waters. Infection can also occur when there are open wounds on our hands and we unknowingly touch moist ground/soil which have been infected by animal’s pee.

Rats are the main sources of carrying and transmitting leptospirosis. However, almost all mammals can carry the infection. Mice, moles, dogs, deer, rabbits, cow, sheep, raccoons, skunks are also considered common animals of infection.


some things to consider first...

some things to consider first…

To Go For A Dip Or Not?

It is a dilemma to hike to a nice waterfall only to sit by the rocks. Hence, we need to strike a balance between risking an infection and having fun. Here are some of the things I evaluate before deciding:

  • If there are already reports, notices, signboard or warning about an outbreak or water contamination, avoid contact with the raw water or potentially infected sources at all cost.
  • Campsite, parks or hiking locations which are badly littered or poorly maintained have a higher risk of contamination. Food waste and rubbish left behind creates a breeding ground for rats. Exercise caution in these areas and avoid contact with raw water or potentially infected source.
  • If the campsite, park or hiking location is well managed and/or have organisation overseeing the location, you can get advice from them on their opinion on the matter. They have will better knowledge of the environment and situation.
  • Do not drink water without boiling or chemically treating it first. Chlorinated water has shown to prevent transmitting leptospirosis. Use water purification tablets when you can’t boil the water.
  • If you need to go into the water (river crossing etc), check for cuts and open wounds on your bodies. Use waterproof dressing on them to prevent bare skin exposure.
  • If you are swimming or playing by the waterfalls, do note on the above and avoid putting your head underwater. If you need to, wear goggles or diving mask to protect your eyes and nose from exposure.


A quick run down on the hotspots and statistics of Leptospirosis outbreak in Malaysia for 2016 so far2:

  • 14 leptospirosis outbreaks
  • 2,200 cases of leptospirosis reported
  • 2 Deaths, suspected to be infected through recreation activities
  • Half of the outbreaks are in Selangor
  • Kelantan has 365 case, (the most)
  • Sarawak has 362 cases
  • Terengganu has 323 case

if only you are carrying less disease

Consequence and Dealing with Leptospirosis

Getting infected does not necessary means facing death. To put things in context, WHO estimates 5-15% of untreated cases progress to complications and potentially death1. In Malaysia between 2004-2009 on average, less than 5% of report cases of leptospirosis ends up in death3.

I am unable to obtain any recent figures, but the data is in line with WHO estimates. 

An infected person usually start showing the below symptoms between 5-14 days, but can be as early as 2 days or as late as 30 days.

Symptoms includes:

  • High fever,
  • Severe headache,
  • Muscle pain,
  • Chills,
  • Redness of the eyes,
  • Abdominal pain,
  • Jaundice,
  • Vomiting,
  • Diarrhoea,
  • Rash,
  • Haemorrhages in the skin and mucous membranes.

The treatment for Leptospirosis is antibiotic therapy, and best results are obtained when the therapy is initiated at the early stages.

However, early stage Leptospirosis is often misdiagnosis with other types of diseases such as dengue, typhoid or viral hepatitis as the symptoms are very similar and general. 

A correct and accurate diagnosis is the main challenge. We often may mistaken leptospirosis symptoms with the common illness such as fever and food poising etc. 

Therefore, do not take things lightly if you fall sick after an outdoor hiking trip. Consult a doctor and let them know about your activities and places you have been. Give as much information and details as possible for them to evaluate your case.

Once suspected of infection, doctors can then use the appropriate laboratory test to confirm. WHO suggest that clinicians should never wait for the results of laboratory test before starting treatment with antibiotics1.

The best bet for a full and speedy recovery is to get a correct diagnosis early on.


Be safe, have fun!


1: World Health Organisation 
2: Straits Time News Report 
3: Malaysia Ministry Of Health 


Posted in Hiking Tips & Treats.

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