From the Guidelines
Cyclones pose significant environmental health threats, including contaminated water, vector-borne diseases, mold growth, and chemical hazards, which can be mitigated with proper precautions and immediate attention. After a cyclone, the most urgent concern is contaminated water, as flooding mixes sewage with drinking water supplies, potentially causing cholera, E. coli, and other waterborne diseases 1. To address this, it is essential to boil water for at least one minute, use water purification tablets containing chlorine dioxide, or add 8 drops of unscented household bleach per gallon of clear water (16 drops if cloudy) and wait 30 minutes before consumption.
Vector-borne diseases, such as malaria, dengue fever, and West Nile virus, increase as mosquitoes breed in standing water 1. To prevent this, it is crucial to eliminate water containers, use DEET-based repellents (20-30% concentration), and sleep under insecticide-treated nets. Mold growth occurs rapidly in damp buildings, causing respiratory issues, and can be cleaned with 1 cup bleach per gallon of water while wearing protective equipment.
Chemical hazards from damaged industrial facilities or household products require avoiding contact and reporting spills to authorities 1. Food safety becomes compromised due to power outages, and perishables left above 40°F (4°C) for more than 2 hours should be discarded. These threats emerge because cyclones disrupt normal environmental protections and infrastructure, creating conditions where pathogens thrive and exposures to harmful substances increase.
Key precautions to take after a cyclone include:
- Boiling or purifying water before consumption
- Eliminating standing water to prevent mosquito breeding
- Using DEET-based repellents and sleeping under insecticide-treated nets
- Cleaning mold-affected areas with bleach and wearing protective equipment
- Avoiding contact with chemical hazards and reporting spills
- Discarding perishables left above 40°F (4°C) for more than 2 hours.
By taking these precautions, the risk of environmental health threats posed by cyclones can be significantly reduced, ultimately minimizing morbidity, mortality, and improving quality of life 1.
From the Research
Environmental Health Threats from Cyclone
- Cyclones can contaminate water sources, leading to the spread of waterborne diseases such as cholera, typhoid fever, and bacillary dysentery 2
- The lack of basic hygiene and sanitation, as well as failing infrastructure, can exacerbate the risk of waterborne diseases in the aftermath of a cyclone 3
- Some of the diseases that can be transmitted by water and may be prevalent after a cyclone include:
- Acute otitis externa
- Campylobacteriosis
- Cryptosporidiosis
- Escherichia coli infection
- Free-living ameba infection
- Giardiasis
- Hepatitis A virus (HAV) infection
- Legionnaires' disease
- Nontuberculous mycobacterial (NTM) infection
- Pseudomonas-related pneumonia or septicemia
- Salmonellosis
- Shigellosis
- Vibriosis or cholera 4
- The economic burden of these diseases can be significant, with estimated annual costs of $3.8 billion in the United States alone 4
- Antibiotic resistance is a growing concern, and combination therapy may be effective in treating certain waterborne diseases, such as Vibrio vulnificus septicemia 5
- Research is ongoing to evaluate the efficacy of different antibiotics, such as doxycycline, ciprofloxacin, and levofloxacin, in treating waterborne diseases 5, 6