Leptospirosis is not just deadly. It is very expensive. More than just a disease caused by rat pee, its spread associated by most people of floods, leptospirosis is costly: P15,487 or almost double the monthly income of minimum wage earners. That is the economic cost per case, or the sum of medical care expenditures and median income losses of patients and care givers.

Then there is the Disability Adjusted Life Years Lost (DALYs) due to leptospirosis. It is computed by combining the years of healthy life lost (YLL) due to premature mortality with the years of like lived with disabilities (YLD). The formula is used by many countries as a guide in setting health priorities.

In Metro Manila, the DALYs per 100,000 population is 25.4, of which 92 percent were accounted for by years of life lost (YLL) due to premature deaths. Only 8 percent was due to years lost due to living with disability (YLD).

What’s remarkable is that 89 percent of those affected by leptospirosis are 15 to 59 years old – the economically active age group.

These are the findings of the University of the Philippines (UP) Manila’s College of Public Health in a study conducted to determine the health burden of leptospirosis.

Compared with the estimated of the World Health Organization for the Western Pacific, UP Manila puts the burden of leptospirosis on the same level as the burden of measles, Japanese encephalitis, hepatitis B, malaria, and schistosomiasis. The burden is in face higher than that of dengue and leprosy.

The findings are significant because while the immediate beneficiaries of the study are policy makers, the people ultimately benefits in the prevention and management of the disease.

We believe, it is imperative to document the health and economic impact of leptospirosis in order to determine whether or not it should be considered among the country’s priority public health problems.

The study germinated when the Japanese International Cooperation Agency (JICA) funded the establishment of laboratory and research facilities at the University of the Philippines Manila’s College of Public Health.

The collaborative project on the prevention and control of leptospirosis between UP Manila and the Kyushu University led to research on the burden of the disease. Because JICA support was meant for technology development, funding for the research came from the Department of Science and Technology-Philippine Council for Health Research and Development (DOST-PCHRD).

A study in Metro Manual soon followed. The first phase of our study was meant to fill the gap in the very limited and largely unreliable local data needed to estimate DALYs. Rapid community surveys determined the percentage of the population who were either infected or exposed to the microorganism that causes the diseases.

To determine the rate at which new cases develop, the clinical course of the disease was charted and the cost incurred for its diagnosis and treatment was calculated. These were conducted through interviews with new cases and key informants as well as an extensive review of the literature and other documents such as patient medical charts.

Community surveys revealed that exposure to leptospirosis occur both indoor (rat infestation) and out in open sewers, garbage humps, and filth-riddled creeks. This explains the fact that 26 out of 100 individuals are positive for leptospirosis antibodies, meaning they have somehow encountered the disease enough for immune systems to kick in.

People know leptospirosis as a disease transmitted through the rat urine spread during floods. It is more than just a sickness that comes with high waters because, in extreme cases, it is deadly.

Leptospirosis is caused by bacteria of the genus Leptospira. Left untreated in humans, it may lead to kidney damage, meningitis (inflammation of the membrane around the brain and spinal cord), liver failure, respiratory distress, and death.

And it doesn’t come only with floods and urine. Body fluids of infected animals (swine and cattle, even pets and not just rats) can contaminate soil and water. Drinking contaminated water or contact while swimming or boating is a common transmission route.

There may be no signs at all or the varied symptoms may be mistaken for other ailments. Symptoms usually appear in two days or it may take a month after exposure to the bacteria. They include chills, headache, muscle aches, vomiting, diarrhea, abdominal pain, jaundice (yellowing of the skin and eyes), skin rash, and red eyes.

At risk (especially if they have cuts or abrasion of the skin) are farmers, veterinarians, and animal caretakers (and not just those who wade in floodwaters). Those who work in mines, sewers, slaughterhouses, diaries, and fishermen and people who work with fish are equally at risk.

While it remains one of the “neglected diseases”, leptospirosis affects a relatively large number of high-risk groups when they are exposed to contaminated rivers, creeks, or flood waters. The number of new cases can potentially increase exponentially with the advent of more floods brought by extreme weather caused by climate change.

Antibiotics are the drugs of choice, preferably given as soon as possible. But prevention is still best. For a start, avoid contact with animal urine or body fluids; do not swim, wade in, or swallow contaminated water. Nor for that matter go in contact with contaminated soil or water without protective footwear or clothes.

We hope that leptospirosis would be accorded at least the same importance as current “priority” diseases in terms of prevention and control efforts as well as in terms of research initiatives.

Because rodents breed more in conditions present in poor neighborhoods, health workers should inform the public about the importance of maintaining good sanitary conditions within and outside their homes as protective measures. To prevent floods, the government must implement control measures such as clearing stagnant creeks. The public must be encouraged to properly dispose garbage and reduce the use of plastic that clog waterways.

Because premature deaths greatly increase the disease burden of leptospirosis, health workers should aim for early detection and prompt treatment. Testing for the presence of antibodies, the immune system’s defense against leptospirosis, remains essential. However, rapid diagnostic tests are needed to detect the antigen which produces the antibodies against leptospirosis.


Written by:
Dr. Maridel P. Borja, Nina G. Gloriani, and Shin-ichi Yoshida
University of the Philippines Manila

Published by:
Department of Science and Technology-Science and Technology Information Institute (DOST-STII)