As Metro Manila and outlying provinces recover from three days of torrential monsoon rains, the World Health Organization (WHO) warned against contaminated water and flood-related diseases such as leptospirosis and dengue.
“During flooding, drinking water systems can become contaminated with sewage and grey water,” WHO said in its advisory.
The agency said that the best option is to “use only bottled water for drinking, brushing teeth and cleaning vegetables and fruit that will be eaten raw.”
If bottled water supply is scarce, tap water should be boiled for 20 minutes.
WHO also advised treating water with chlorine when there is no other option available.
People who wade in floodwaters are in danger of acquiring leptospirosis, which is caused by leptospira bacteria that can be found in water that has been contaminated by animal urine.
“The leptospira bacterium enters the body through the eyes, nose, mouth and cuts and grazes on the skin that is immersed in contaminated flood water, mud and vegetation. Exposure through water contaminated by urine from infected animals is the most common route of infection. Human-to-human transmission is rare,” WHO said.
Symptoms of the disease include dry cough, fever and chills, headache and muscle pain and joint pain, as well as nausea, vomiting and diarrhea.
The agency said that if doxycycline prophylaxis antibiotic is taken soon after exposure to floodwaters, leptospirosis can be prevented.
People should also watch out for mosquito-borne diseases during the rainy season.
Cases of dengue, chikungunya and other mosquito-borne diseases usually rise “two to three weeks after flooding,” WHO said. This is because mosquitoes have plenty of breeding sites, such as cans, tires and other canisters filled with rainwater, rain-fed gutters or stagnant pools of water left uncleaned.
Symptoms of these diseases appear three to 14 days after the infective bite.
These include mild to incapacitating high fever, headache and pain behind the eyes, muscle and joint pain, and skin rash.
There are no specific antiviral medicines for dengue and chikungunya, and WHO advised against the use of acetylsalicylic acid (e.g. aspirin) or non-steroidal anti-inflammatory drugs (e.g. Ibuprofen) for dengue since these drugs could induce bleeding.
Other signs for mosquito-borne diseases include abdominal pain and tenderness, persistent vomiting, mucosal bleeding and lethargy or restlessness.